CN101025233B - Load control structure for work vehicle - Google Patents

Abstract

A load control structure for a work vehicle comprises: a device for detecting operating position of a speed change operating element; an engine load detection device for detecting load on an engine; a swash plate position detecting device for detecting an operating position of a swash plate of a variable displacement pump; a pump operating device for steplessly operating the swash plate of the variable displacement pump; a motor operating device for operating a swash plate of a variable displacement motor between at least two speed change positions including a higher speed position and a lower speed position; a control device for controlling the operations of the pump operating device and the motor operating device. The control device has a automatic pump swash plate control device for controlling the operation of the pump operating device, based on detected information from the load detection device and detected information from the swash plate position detecting device, such that the greater an engine load is, greater is the extent to which the swash plate of the variable displacement pump is operated to a low speed side; and a motor swash plate control device for controlling the motor operating device so as to change the position of the swash plate of the variable displacement motor between the at least two speed change positions.

Description

The load control structure of operating vehicle

Technical field

The present invention relates to a kind of load control structure of operating vehicle.

Background technique

Load control structure as operating vehicle, two kinds of structures are arranged: a kind of action of controlling motor with operating device in the following manner, promptly, detection according to load detecting mechanism, the swash plate of variable capacity motor rises to predefined first setting value and switches to low-speed position from high speed position with engine loading, and the swash plate of variable capacity motor is reduced to predefined second setting value and switches to high speed position (for example opening flat 6-17928 communique with reference to the spy) from low-speed position with engine loading, the action of operating device of another kind of control pump in the following manner, promptly, based on the detection of load detecting mechanism and the detection of swash plate positions feeler mechanism, the swash plate deceleration-operation degree of the big more variable displacement pump of engine loading is big more.

Control based on the variable capacity pump load is applicable to the underloading operation that engine loading is less, and be applicable to the heavily loaded operation that engine loading is bigger based on the control of variable capacity motor load, but in above-mentioned this existing structure, not for from the less underloading operation suitable load control structure to the so large-scale operation load of bigger heavily loaded operation of engine loading.

Summary of the invention

The object of the present invention is to provide a kind of load control structure, can be suitable for the load control of different engine loadings.

Load control structure according to operating vehicle of the present invention comprises: the operating position feeler mechanism of operating position that is used to detect the variable speed operation spare of manual operation; The load detecting mechanism of detection of engine load; The swash plate positions feeler mechanism of the operating position of the swash plate of the variable displacement pump that detection is had in static oil pressure endless gearing device; The pump operating device of the swash plate of the above-mentioned variable displacement pump of stepless operation; The motor operating device of the swash plate handover operation of the variable capacity motor that will in above-mentioned static oil pressure endless gearing device, be had at least two shift position that comprise high speed position and low-speed position; The control said pump is used the control mechanism of the action of operating device with operating device and said motor; At this, above-mentioned control mechanism comprises: automatic pump swash plate control mechanism, it is according to the action with operating device of the detection control said pump of the detection of above-mentioned load detecting mechanism and above-mentioned swash plate positions feeler mechanism, so that engine loading is big more, the swash plate deceleration-operation degree of above-mentioned variable displacement pump is big more; The control said motor is with the motor swashplate control mechanism of the action of operating device, so that the swash plate of above-mentioned variable capacity motor switches on above-mentioned two shift position at least; Automatic motor swash plate control mechanism, this automatic motor swash plate control mechanism is according to the action with operating device of the detection control said motor of above-mentioned load detecting mechanism, when engine loading rises to the first predetermined setting value, the swash plate of above-mentioned variable capacity motor is switched to above-mentioned low-speed position from above-mentioned high speed position; When engine loading drops to the second predetermined setting value, the swash plate of above-mentioned variable capacity motor is switched to above-mentioned high speed position from above-mentioned low-speed position.

By the two is adjusted to the swash plate of the swash plate of variable displacement pump and variable capacity motor, just can provide and the corresponding load control structure of engine loading on a large scale.

Description of drawings

Fig. 1 is the unitary side view of tractor,

Fig. 2 is the skeleton diagram of the drive mechanism of expression tractor,

Fig. 3 is the longitudinal profile side view of expression tractor drive mechanism major component,

Fig. 4 is the horizontal section plan view of expression tractor drive mechanism major component,

Fig. 5 is oil hydraulic circuit figure,

Fig. 6 is the block diagram of expression control structure,

Fig. 7 is the figure of dependency relation between the operating position of expression operating position of gear shift pedal and pump swash plate,

Fig. 8 is the deviation of expression pump swash plate and the figure of the dependency relation between the object run speed,

Fig. 9 is the figure of dependency relation between the operating position of expression pump swash plate and the engine speed,

The figure of the pump swash plate action when Figure 10 is expression motor swashplate handover operation,

Figure 11 is the figure of the show state of expression pump swash plate positions on TFT LCD,

Figure 12 is the horizontal section plan view of expression mechanical type servo-control mechanism structure major component,

Figure 13 is the oil hydraulic circuit figure that expression has the state of mechanical type servo-control mechanism and switching mechanism,

Figure 14 is the oil hydraulic circuit figure that represents only to have the state of electronic type servo-control mechanism,

Figure 15 is the oil hydraulic circuit figure that represents only to have the state of mechanical type servo-control mechanism,

Figure 16 is the block diagram of mobility operation device,

Figure 17 is the explanatory drawing of common control target speed and Correction and Control target velocity,

Figure 18 is the flow chart of speed Control,

Figure 19 is the flow chart of common speed Control,

Figure 20 is a flow chart of revising speed Control,

Figure 21 is the block diagram of mobility operation device,

Figure 22 is the side view of positioning means,

Figure 23 is the side view of linking mechanism,

Figure 24 is the plan view of rotary dump device and potentiometer assembly department,

Figure 25 is the stereogram of positioning means, acceleration STATEMENT OF FEDERALLY SPONSORED,

Figure 26 is the front view of operating handle guiding element,

Figure 27 is the plan view of the separated state of clamping mechanism,

Figure 28 is the plan view of the fastening state of clamping mechanism,

Figure 29 has the side view that other implement the positioning means of structure.

Embodiment

Below, with reference to the accompanying drawings, embodiments of the present invention are described.A disclosed feature in a plurality of mode of executions can be combined with the disclosed feature of other mode of executions, is appreciated that this combination is also contained in the scope of the present application.

In Fig. 1, expression is as the whole side of the tractor of an example of operating vehicle.This tractor comprises: the forward frame 2 by insulator supporting engine 1, at the front-wheel 3 of above-mentioned forward frame about 2 parts, link to each other with motor 1 and the gearbox 4 that works as framework, the trailing wheel 5 that is located at gearbox about 4.Operating vehicle has the Drive Section of taking 8 above gearbox 4, the described Drive Section 8 of taking comprises steering wheel 6 and pilot set 7 etc.

Shown in Fig. 2～4, the power of motor 1 is by dry type main clutch 9 etc., is delivered to as the main transformer quick-mounting to put and in the static oil pressure endless gearing device (example of stepless speed changes devices) 10 that works.Be delivered to left and right sides front-wheel 3 and left and right sides trailing wheel 5 with differential motion 12 or trailing wheel with differential motion 13 etc. by gear type speed change gear (example of step change device) 11 and front-wheel with power from travelling of taking out of this static oil pressure endless gearing device 10, said gear formula speed change gear 11 switches to high, normal, basic three grades secondary speed-changing device as variable speed and works.The operation of taking out from this static oil pressure endless gearing device 10 is delivered to pto 15 with operation clutch 14 grades of power by hydraulic type.

Gearbox 4 is by being connected with each other the interior first housing section 4A of main clutch 9 grades, the interior second housing section 4B of static oil pressure endless gearing device 10 etc., interior the 3rd housing section 4C of operation clutch 14 etc., interior the 4th housing section 4D that is adorning gear type speed change gear 11 etc. of adorning of adorning of adorning to constitute.

Shown in Fig. 2～5, in comprising, static oil pressure endless gearing device 10 is contained in interior axial piston variable displacement pump 16 of the second housing section 4B and axial piston variable capacity motor 17 etc., non-variable-speed dynamic from variable displacement pump 16 is exported with power as operation, variable-speed dynamic from variable capacity motor 17 is exported with power as travelling, the supply oil that comes the supply pump 21 that free engine power drives is via supplying with oil circuit 22 and one-way valve 23 etc., supplies to by first oil circuit 18 to be connected variable displacement pump 16 and variable capacity motor 17 with second oil circuit 19 and in the closed-loop path 20 that forms.

Shown in Fig. 1 and Fig. 4～6, servo-control mechanism 25 is being set in this tractor, the operation of the neutral homing position type gear shift pedal (example of variable speed operation spare) 24 that described servo-control mechanism 25 bases have in taking Drive Section 8 etc., operate swash plate (below, the be called the pump swash plate) 16A of variable displacement pump 16.

Shown in Fig. 4～6, servo-control mechanism 25 comprises: the pumping cylinder of the hydraulic type of stepless operating pumps swash plate 16A (example of operation mounting mechanism) 26, the Control work oil phase is to the servovalve 27 that flows of pumping cylinder 26, the oil pressure of relative servovalve 27 grades is maintained the modulating valve 28 of setting pressure, the pedal sensor (example of operating position feeler mechanism) 29 that constitutes by the potentiometer of the operating position that detects gear shift pedal 24, the swash plate sensor (example of shift position feeler mechanism) 30 that constitutes by potentiometer from the operating position of the operation amount testing pump swash plate 16A of pumping cylinder 26, and the control mechanism (example of control mechanism) 31 that constitutes by the microcomputer of testing result of detection that is transfused to pedal sensor 29 and swash plate sensor 30 etc. etc.

Pumping cylinder 26 is contained in the second housing section 4B in advance retarding spring 32 and the laggard retarding spring 33 that the pump swash plate 16A application of force are made it restore to the neutral position, the grease chamber 34 that uses by the speed change of marching forward supplies with working oil, then overcome the application of force of the retarding spring 32 that advances and the speedup direction operating pumps swash plate 16A that marches forward, supply with working oil by the grease chamber that uses to laggard speed change 35, then overcome laggard retarding spring 33 the application of force and to laggard speedup direction operating pumps swash plate 16A.

Servovalve 27 comprises that the electromagnetic types that flow in grease chamber 34 that the Control work oil phase is used the speed change of advancing of pumping cylinder 26 advance with Proportional valve 36, the laggard Proportional valve 37 etc. of using of electromagnetic type that the Control work oil phase flows to the grease chamber 35 that the laggard speed change of pumping cylinder 26 is used, the working oil of supply pump 38 force feeds that modulating valve 28 will be used from servosteering is assigned to the power steering gear 39 of operation clutch 14 and hydraulic type with the setting pressure that is suitable for working separately, at the relative pressure port 28A place of the supply oil circuit 40 connected modulating valve 28 of operation clutch 14, connecting the supply oil circuit 41 of relative servovalve 27.

Control mechanism 31 have known MPU, storage, for carry out with the communication function of other equipment and specification in required known hardware and the algorithm of function that illustrate.

As shown in Figure 6, in control mechanism 31, has pump swash plate control mechanism 31A, described pump swash plate control mechanism 31A storage is provided with: map datum (examples of dependency relation data), dependency relation between the operating position of expression gear shift pedal 24 and the operating position of pump swash plate 16A; And control program, by advancing with Proportional valve 36 or laggard action with Proportional valve 37 according to the detection control of the detection of this map datum and pedal sensor 29 and swash plate sensor 30, and operating pumps swash plate 16A.

The map datum of pump swash plate control mechanism 31A is the operating position corresponding map data that make the operating position and the pump swash plate 16A of gear shift pedal 24 in the following manner, promptly, march forward from the neutral position operation amount of speedup direction of gear shift pedal 24 is big more, march forward from the neutral position operation amount of speedup direction of pump swash plate 16A is big more, the operation amount to laggard speedup direction is big more from the neutral position for gear shift pedal 24, and pump swash plate 16A is the operation amount to laggard speedup direction big more (with reference to figure 7) from the neutral position.

The control program of pump swash plate control mechanism 31A is according to the detection of map data stored and pedal sensor 29, and the operating position of pump swash plate 16A that will be corresponding with the operating position of pedal sensor 29 detected gear shift pedals 24 is set at the object run position of pump swash plate 16A.According to the object run position of setting and the detection of swash plate sensor 30, control is advanced with Proportional valve 36 or laggard action with Proportional valve 37, makes object run position and the actual operational position of pump swash plate 16A consistent.By this control action, just can car body be advanced or laggard.

Promptly, servo-control mechanism 25 is a kind of like this electronic equipments, pump swash plate control mechanism 31A is according to the detection of pedal sensor 29 and the detection of swash plate sensor 30, control is advanced with Proportional valve 36 or laggard action with Proportional valve 37, thereby makes pumping cylinder 26 actions and the pump swash plate 16A of operation static oil pressure endless gearing device 10.Servo-control mechanism 25 is by coming direct-driven pump cylinder 26 (straight ejector half) via advancing of the pressure port 28A of modulating valve 28 with Proportional valve 36 or laggard delivery pressure with Proportional valve 37.Thus, compare with the situation that drives pumping cylinder 26 by delivery pressure from supply oil circuit 22, can obtain stable pilot servo pressure, can accurately control the action of pumping cylinder 26, described supply oil circuit 22 produces pressure oscillation because of the change of the pressure oscillation in the closed-loop path 20 of static oil pressure endless gearing device 10 or engine speed.As a result, servo-control mechanism 25 can constitute cheap straight ejector half, and can be according to the detection of pedal sensor 29 and the detection of swash plate sensor 30, controls accurately that car body advances or laggard with the speed corresponding with the operating position of gear shift pedal 24.

In control mechanism 31, be provided with the first service speed setting device 31B, described first service speed setting device 31B storage is provided with: according to the object run position of the pump swash plate 16A that is set by pump swash plate control mechanism 31A and the detection of swash plate sensor 30, calculate the object run position of pump swash plate 16A and the operation program of the deviation between the actual operational position; A plurality of map datums (examples of dependency relation data) of dependency relation between the service speed of the object run position of expression pump swash plate 16A and the deviation of actual operational position and pump swash plate 16A; Set the control program of the object run speed of pump swash plate 16A according to the result of calculation of these map datums and operation program.

Each map datum of the first service speed setting device 31B makes the deviation of pump swash plate 16A and the corresponding map datum of service speed of pump swash plate 16A in the following manner, promptly, when the deviation ratio between the object run position of the actual operational position of the pump swash plate 16A that is detected by swash plate sensor 30 and the pump swash plate 16A that set by pump swash plate control mechanism 31A is big, improve the service speed of pump swash plate 16A, service speed with respect to the pump swash plate 16A of the deviation of pump swash plate 16A is compared when advancing in addition, makes when laggard service speed slack-off (with reference to figure 8) with respect to the pump swash plate 16A of the deviation of pump swash plate 16A.

The control program of the first service speed setting device 31B is according to the map datum of storage setting and the result of calculation of operation program, the service speed of pump swash plate 16A that will be corresponding with the deviation of the pump swash plate 16A that calculates is set at the object run speed of pump swash plate 16A, and the object run speed that will set outputs to pump swash plate control mechanism 31A.

In speed of a motor vehicle control, the control program control of pump swash plate control mechanism 31A is advanced with Proportional valve 36 or laggard action with Proportional valve 37, so that use the object run speed of being set by the first service speed setting device 31B to come operating pumps swash plate 16A.By this control action, just can improve the responsiveness of relative gear shift pedal 24 operations of pump swash plate 16A and the generation of suppress to fluctuate (hunching).As a result, just can be rapidly and the speed of a motor vehicle is reached and the corresponding speed of the operating position of gear shift pedal 24.The service speed of the service speed of pump swash plate 16A when laggard pump swash plate 16A when advancing is slow, when laggard the variable speed operation of static oil pressure endless gearing device 10 also when advancing the variable speed operation of static oil pressure endless gearing device 10 mild, therefore compare when advancing and be difficult to aware velocity sense, and carry out the variable speed operation of the static oil pressure endless gearing device 10 when laggard easily.

In control mechanism 31, comprise the 31C of data change mechanism with control program, described control program changes the employed map datum of the first service speed setting device 31B, as described below, the 31C of data change mechanism can suitably change the employed map datum of the first service speed setting device 31B according to various situations.

The 31C of data change mechanism is according to the operating position by the adjusting dial that potentiometer constituted that has in taking Drive Section 8 (example of manual operation part) 42, in order to make the operating position of regulating dial 42 big more to quick side change from the reference position, the service speed of pump swash plate 16A is carried out more apace, and the service speed that the map datum that uses is changed to respect to the pump swash plate 16A of the deviation of pump swash plate 16A accelerates so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A, and, in order to make the operating position of regulating dial 42 big more to the deceleration side change from the reference position, the operation of pump swash plate 16A is gently carried out more, and the map datum that uses is changed to slack-off so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A with respect to the service speed of the pump swash plate 16A of the deviation of pump swash plate 16A.

That is, by operating regulation dial 42, the operation feeling in the time of can changing by gear shift pedal 24 variable speed operation static oil pressure endless gearing devices 10 according to driver's hobby, thus just can improve operation feeling and variable speed operation.

The detection of the oil temperature sensor 43 that the 31C of data change mechanism detects according to the temperature to the working oil of the supply in the modulating valve 28, in order to make the working oil temperature low more, the operation of pump swash plate 16A is gently carried out more, makes slack-off so that the data of the service speed correspondence of the deviation of pump swash plate 16A and pump swash plate 16A with respect to the service speed of the pump swash plate 16A of the deviation of pump swash plate 16A and the map datum that uses is altered to reduction according to the oil temperature.

Promptly, the temperature of considering working oil is low more, the viscosity of working oil is high more, the responsiveness of the pump swash plate 16A of hydraulic operation is low more, and the working oil temperature is low more, more the object run speed with pump swash plate 16A is set at slow speed, thus under the situation of not considering the working oil temperature, can suppress low more easy more cause, the generation that reduces the fluctuation that causes because of the responsiveness of pump swash plate 16A of the temperature of working oil.

The 31C of data change mechanism is according to by the detection from the secondary speed change sensor that potentiometer constituted (example of speed change level feeler mechanism) 45 of the speed change level of the operating position measuring gear formula speed change gear 11 of the secondary speed change lever 44 that has during taking Drive Section 8, in order to make the speed change level of gear type speed change gear 11 be in high-speed side more, the operation of pump swash plate 16A is more quickly carried out, and is altered to the map datum that uses corresponding with the rising of the speed change level of gear type speed change gear 11 and the service speed with respect to the pump swash plate 16A of the deviation of pump swash plate 16A is accelerated so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A.

Promptly, the speed change level of gear type speed change gear 11 is set in high-speed side more, the fast speeds for slow this situation of reaction of the operation of pump swash plate 16A has been considered in the object run speed setting of pump swash plate 16A, thus, irrelevant with the speed change level of gear type speed change gear 11, the operation feeling in the time of can making by gear shift pedal 24 variable speed operation static oil pressure endless gearing devices 10 becomes identical.

The 31C of data change mechanism is according to the detection of the service speed feeler mechanism 46 of the service speed that detects gear shift pedal 24, in order to make the service speed of gear shift pedal 24 slow more, the operation of pump swash plate 16A is gently carried out more, and is altered to the map datum that uses corresponding with the reduction of the service speed of gear shift pedal 24 and makes slack-off so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A with respect to the service speed of the pump swash plate 16A of the deviation of pump swash plate 16A.In time the service speed that differential just can obtain gear shift pedal 24 is carried out in the output of pedal sensor 29.Therefore, can consider feeler mechanism 46 is made of pedal sensor 29 and control mechanism 31.

The result, even under the situation that gear shift pedal 24 is operated by dead slow speed, pump swash plate 16A also is later than the operation of gear shift pedal 24 and follows gear shift pedal 24, avoid the operation of pump swash plate 16A to catch up with the operation of gear shift pedal 24 and carry out the possibility that stair-stepping step change is operated, therefore and the service speed of gear shift pedal 24 have nothing to do, can carry out the variable speed operation of static oil pressure endless gearing device 10 smoothly by gear shift pedal 24.

And service speed feeler mechanism 46 comprises the operation program that pedal sensor 29 and the 31C of data change mechanism are had, and described operation program goes out the service speed of gear shift pedal 24 according to the detection computations of this pedal sensor 29.

The 31C of data change mechanism is according to the detection of swash plate sensor 30, be in the neutral position or near the neutral position time at the operating position that detects pump swash plate 16A, in order gently to carry out the operation of pump swash plate 16A,, the map datum that uses is limited to low speed side so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A and being changed to the service speed that makes with respect to the pump swash plate 16A of the deviation of pump swash plate 16A.

The result, in the time of near pump swash plate 16A is positioned at neutral position or neutral position, even gear shift pedal 24 is carried out the rapid operation of trampling, pump swash plate 16A yet can not trample operation and carries out speedup operation rapidly along with this, this pump swash plate 16A is gently carried out the speedup operation, even therefore gear shift pedal 24 is carried out the rapid operation of trampling, also can prevents unexpected acceleration, thereby can start smoothly or quicken by unexpected startup or dead slow speed generation suddenly.

The number pick change 31C of mechanism is according to the detection of the turn-sensitive device (example of load detecting mechanism) 47 of detection of engine rotating speed, object run position with the pump swash plate 16A that sets by pump swash plate control mechanism 31A, when engine speed reduces with the object run set positions of pump swash plate 16A under the situation of low speed side, for the operation that makes pump swash plate 16A is carried out apace, make slack-off so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A with respect to the service speed of the pump swash plate 16A of the deviation of pump swash plate 16A and the map datum that uses is altered to reduction according to engine speed.The object run set positions that detects pump swash plate 16A when engine speed rises is under the situation of high-speed side, for the operation that makes pump swash plate 16A is gently carried out, the service speed with respect to the pump swash plate 16A of the deviation of pump swash plate 16A is accelerated so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A and the map datum that uses is altered to rising according to engine speed.

Thus, if when the engine speed that causes because of increases such as the loads of travelling reduces, gear shift pedal 24 is operated deceleration side, then based on this operation, just can carry out the operation of pump swash plate 16A rapidly, thereby impel the load of motor to reduce towards deceleration direction.Thus, although gear shift pedal 24 is carried out deceleration-operation, but can suppress to produce the possibility of following problems, described problem refer to owing to and the deceleration-operation of the static oil pressure endless gearing device 10 that links of this operation that engine loading is reduced is slack-off, thereby shutting engine down 1.In addition, travel load etc. and when engine speed is risen in minimizing, even gear shift pedal 24 is operated the speedup side, based on this operation, also can carry out the operation of pump swash plate 16A lentamente to the speedup direction, therefore, the unexpected speed of a motor vehicle that just can avoid the speedup operation because of the rising of engine speed and pump swash plate 16A to produce rapidly increases.That is, although the engine speed change also can be carried out variable speed operation by 24 pairs of static oil pressure endless gearing devices of gear shift pedal 10 well.

The 31C of data change mechanism is according to the detection of the braking sensor that potentiometer constituted that is detected the action of braking device (not shown) by the operating position of the brake petal from take Drive Section 8 48 (example of braking feeler mechanism) 49, when braking device carries out braking maneuver, in order to carry out the operation of pump swash plate 16A rapidly to deceleration direction, consider that the braking maneuver because of braking device reduces the speed of a motor vehicle, accelerate so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A and the map datum that uses is altered to the service speed that makes with respect to the pump swash plate 16A of the deviation of pump swash plate 16A.

Thus, just can be suppressed at and remove the trampling operation of gear shift pedal 24 and when brake petal 48 trampled the braking maneuver of operation, interference between static oil pressure endless gearing device 10 and the braking device, but also can improve the serviceability of static oil pressure endless gearing device 10 and braking device.

The 31C of data change mechanism is according to the detection that is detected the vehicle speed sensor (speed of a motor vehicle feeler mechanism) 50 of the speed of a motor vehicle by the output speed of gear type speed change gear 11, under the slower situation of the speed of a motor vehicle, in order gently to carry out the operation of pump swash plate 16A, make slack-off so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A with respect to the service speed of the pump swash plate 16A of the deviation of pump swash plate 16A and the map datum that uses is altered to reduction according to the speed of a motor vehicle.

Thus, when low speed driving, reduce the responsiveness of pump swash plate 16A, (the inching: small operation) operation of the slow-action of the desired speed of a motor vehicle in the time of just can easily carrying out low speed driving with respect to the operation of gear shift pedal 24.

The object run position of the pump swash plate 16A that the 31C of data change mechanism sets according to the detection of swash plate sensor 30 and pump swash plate control mechanism 31A, with the map datum that uses be altered to make according to the object run position of pump swash plate 16A and actual operational position different with respect to the service speed of the pump swash plate 16A of the deviation of pump swash plate 16A so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A, thereby when making in the object run position of pump swash plate 16A than the more close speedup side of actual operational position, the operation of pump swash plate 16A is gently carried out, and in the object run position of pump swash plate 16A during than the more close deceleration side of actual operational position, the operation of pump swash plate 16A is carried out rapidly, and then when the neutral position in clamping between the object run position of pump swash plate 16A and actual operational position, more promptly carry out the operation of pump swash plate 16A.

Thus, just can be by by the speedup operation of the static oil pressure endless gearing device 10 of gear shift pedal 2 and deceleration-operation and the handover operation sensation.In addition, can suppress the speedup of static oil pressure endless gearing device 10 and operate the engine loading increase that is produced, therefore and can promote the engine loading that deceleration-operation produced of static oil pressure endless gearing device 10 to reduce, just can reduce when high capacity the situation that the variable speed operation because of the static oil pressure endless gearing device 10 that utilizes gear shift pedal 24 stops motor 1.And then, suppressing the delay of the operation of pump swash plate 16A with respect to the operation of gear shift pedal 24, handover operation is advanced in the front and back that can carry out static oil pressure endless gearing device 10 by gear shift pedal 24 comfily.

The object run position of the pump swash plate 16A that the 31C of data change mechanism sets according to the detection of swash plate sensor 30 and pump swash plate control mechanism 31A, in order to begin the travelling during beginning of speedup operation from the neutral position at pump swash plate 16A, the operation of pump swash plate 16A is gently carried out, make slack-off so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A when being altered to the map datum that uses according to starting with respect to the service speed of the pump swash plate 16A of the deviation of pump swash plate 16A, and, pump swash plate 16A from speedup position deceleration-operation when travelling of neutral position stops, in order to carry out the operation of pump swash plate 16A rapidly, the map datum that uses is altered to the service speed that makes when stopping with respect to the pump swash plate 16A of the deviation of pump swash plate 16A accelerates so that the service speed corresponding map data of the deviation of pump swash plate 16A and pump swash plate 16A.

Thus, by operation gear shift pedal 24, the handover operation sensation when stopping of just can and travelling when travelling beginning, the unexpected startup that produces in the time of can suppressing simultaneously to travel beginning.

In addition, comprised as the map datum of the first service speed setting device 31B and to be used to set advancing with map datum and being used to set the laggard map datum of using of variable speed operation speed when laggard of variable speed operation speed when advancing, the 31C of data change mechanism also can be according to the detection of pedal sensor (feeler mechanism is entered in front and back) 29, the map datum that change is used.

But, when carrying out neutral reset operation (deceleration-operation) by advance retarding spring 32 and 33 pairs of pump swash plates of laggard retarding spring 16A, reasons such as inertia during owing to the tractor operation, the speed operation also is difficult to carry out the deceleration-operation of pump swash plate 16A towards the neutral position although gear shift pedal 24 slows down.

Therefore, pump swash plate control mechanism 31A is according to the detection of pedal sensor 29 and the detection of swash plate sensor 30, although gear shift pedal 24 carry out deceleration-operation, but detect when not carrying out deceleration-operation by advance retarding spring 32 and 33 pairs of pump swash plates of laggard retarding spring 16A, with pump swash plate 16A is carried out the opposite side of a speedup employed side of when operation in current operating position, control is advanced with Proportional valve 36 or laggard action with Proportional valve 37, and makes pumping cylinder 26 force action to pump swash plate 16A is decelerated operation towards the neutral position direction.

The result, reasons such as inertia owing to the tractor operation time, although but gear shift pedal 24 carries out deceleration-operation pump swash plate 16A when not carrying out deceleration-operation, also can be by pump swash plate control mechanism 31A to advancing with Proportional valve 36 or laggard action control with Proportional valve 37, make pumping cylinder 26 force action, thereby make pump swash plate 16A deceleration-operation.

In Fig. 9 A, the engine stall performance of the operating vehicle of static oil pressure endless gearing device 10 is being carried in expression.This engine stall performance is by the output torque of motor 1, the pressure of static oil pressure endless gearing device 10, the operating position decisions such as (swash plate angles) of pump swash plate 16A.

Line L shown in Fig. 9 A is the engine stall performance line of the variable speed operation position of engine speed and pump swash plate 16A being carried out balance when the maximum load of static oil pressure endless gearing device 10, described static oil pressure endless gearing device 10 forms, owing to the load of travelling makes static oil pressure endless gearing device 10 ejection high pressure gas.

And in Fig. 9 A, engine speed is 100% to set rotating speed, the operating position of pump swash plate 16A with maximum speedup position (maximum swash plate angle) as 100%.

If according to Fig. 9 A, engine stall performance to the operating vehicle of carrying static oil pressure endless gearing device 10 describes, then pump swash plate 16A is being remained under the state of certain operating position consistently, when motor 1 also being applied operation load of being used to drive apparatus for work etc. except applying the load of travelling, shown in an a, the operating position of engine speed and pump swash plate 16A drops among the ratio engine stall performance line L regional Za more in the inner part sometimes.

At this moment, the stable status such as operation load beyond the load of travelling are even the load of travelling increases, engine speed can not reduce yet, if but make the load increases such as operation load in addition of travelling, then engine speed can reduce, and makes motor 1 stop (stall).

Under pump swash plate 16A remains on state on a certain operating position consistently, shown in a b, in the time of in the regional Zb of the operating position of engine speed and pump swash plate 16A in regional Zb, the Zc in the engine stall performance line L outside, if increase the load of travelling, then engine speed can reduce, and motor 1 is stopped.

Under pump swash plate 16A remains on state on a certain operating position consistently, shown in a c, the operating position of engine speed and pump swash plate 16A is in regional Zc the time, if increase the load of travelling, till arriving engine stall performance line L, engine speed can reduce, and arrives engine stall performance line L and engine speed and settles out.

And about engine stall performance line L, motor output is low more, the engine speed among relative Fig. 9 A, and the operating position of pump swash plate 16A diminishes more.

That is, 1 output of the motor of lift-launch is low more, travels or climbs in the bigger operation of the load of travelling and travel, and when trampling the speedup operation of above-mentioned gear shift pedal 24 significantly, is easy to more cause engine stall because of overload.

Therefore as shown in Figure 6, in this tractor, control mechanism 31 comprises automatic pump swash plate control mechanism 31D, and it changes the operating position of pump swash plate 16A according to engine loading.

Shown in Fig. 6 and Fig. 9 B, automatic pump swash plate control mechanism 31D storage is provided with: according to setting turn-sensitive device (setting an example of rotary speed tester structure) 52 the detection and the detection of turn-sensitive device 47, the calculation engine rotating speed is from the operation program of the reduction amount of setting rotating speed (below, be called the motor slippage); A plurality of map datums (examples of dependency relation data) of dependency relation between the operating position of expression engine speed and pump swash plate 16A; And according to the result of calculation and the map datum of this operation program, control is advanced with Proportional valve 36 or laggard action with Proportional valve 37, thus the control program that pump swash plate 16A is operated; Above-mentioned setting turn-sensitive device 52 is made of the potentiometer that the operating position of the accelerator rod 51 that has from take Drive Section 8 detects the setting rotating speed of motor 1.

Each map datum of automatic pump swash plate control mechanism 31D is determined by engine stall performance line L, at this, under the situation that till predetermined engine revolution zone h engine speed has reduced, engine speed reduces more, the boundary operating position that makes pump swash plate 16A is the closer to the neutral position, and the boundary operating position of pump swash plate 16A is not set in the neutral position, make the operating position correspondence (with reference to figure 9B) of engine speed and pump swash plate 16A.

At length, shown in Fig. 9 B, in predetermined engine revolution zone, in the little first area h1 of motor slippage, the variable quantity of engine speed strengthens the variable quantity of pump swash plate 16A relatively, makes the operating position correspondence of engine speed and pump swash plate.

In the motor slippage second area h2 bigger than first area h1, the variable quantity of engine speed reduces the variable quantity of pump swash plate 16A relatively, and, in the load of travelling, have the point of safes p that the engine speed of making can not reduce, make the operating position correspondence of engine speed and pump swash plate 16A.

In the motor slippage three regional h3 bigger than second area h2, the variable quantity of engine speed strengthens the variable quantity of pump swash plate 16A relatively, makes the operating position correspondence of engine speed and pump swash plate 16A.

The control program of automatic pump swash plate control mechanism 31D constitutes, result of calculation and map datum according to operation program, the pump swash plate 16A operating position of the motor slippage that will calculate corresponding to operation program is located on the boundary operating position of pump swash plate 16A, and according to the detection of the boundary operating position and the swash plate sensor 30 of this setting, control with Proportional valve 36 or laggard action advancing, make boundary operating position and the actual operational position of pump swash plate 16A consistent with Proportional valve 37.

Promptly, by being provided with automatic pump swash plate control mechanism 31D, because of engine loading rises, when engine speed drops to first area h1, carry out load control, prevent preferentially that on one side engine stall from making driving torque increase on one side, that is, pump swash plate 16A is returned on deceleration direction significantly and make the reduction that underspeeds of engine speed.

And, no matter whether carry out this load control, when engine speed is reduced to second area h2, all carry out load control, preferential on one side increase driving torque prevents engine stall on one side, that is, make the deceleration-operation amount that reduces pump swash plate 16A, increase driving torque when making the driver experience engine loading.

In addition, if the engine loading of this moment is the load of travelling, then along with arriving point of safes p, engine speed can not descend from the engine speed corresponding with point of safes p.

And, except the load of travelling, owing to for example can drive the load of the generations such as descending operation that connect the apparatus for work that is provided with up and down, when engine speed is reduced to the 3rd regional h3, carry out load control, prevent preferentially that on one side engine stall from guaranteeing driving torque on one side, that is, pump swash plate 16A is returned on deceleration direction significantly and make the reduction that lowers speed of engine speed.

The result, when connecting the ploughing and weeding operation that tillage device is set when in tractor, connecting the charging crane operation that front-end loader A (with reference to figure 6) is set or in tractor etc., even the driver has not considered the variable speed operation of operation load, also can prevent to produce the load control of engine stall, thereby improve operability and operation because of overload.

In addition, for this load control, because the boundary operating position of pump swash plate 16A is not set in the neutral position, so because of this load control, pump swash plate 16A can not turn back to the neutral position, and the load control during by climbing just can be avoided pump swash plate 16A to turn back to the neutral position in advance and make car body carry out the generation of the problem of uncertain backward motion.

And the difference of Fig. 9 B and Fig. 9 C is, utilizes engine speed on the longitudinal axis of Fig. 9 C.The setting of the map datum when MAX represents that load is big, the setting of the map datum when IDL represents that load is low.

Comprise the second service speed setting device 31E in control mechanism 31, this device 31E storage is provided with: a plurality of map datums of the dependency relation between the pace of change of expression engine speed and the service speed of pump swash plate 16A; Set the control program of the object run speed of pump swash plate 16A with the detection of the pace of change feeler mechanism of detecting according to these map datums with to the pace of change of engine speed 53.

Each map datum of the second service speed setting device 31E is the fast more service speed that makes pump swash plate 16A more of the pace of change of engine speed is accelerated and to make the pace of change of engine speed and the corresponding map datum of service speed of pump swash plate 16A.

The control program of the second service speed setting device 31E constitutes, according to the map datum of store setting and the detection of pace of change feeler mechanism 53, the service speed of the corresponding pump swash plate of the engine speed change speed 16A that will detect with pace of change feeler mechanism 53 is set at the object run speed of pump swash plate 16A, and the object run speed that will set outputs among the automatic pump swash plate control mechanism 31D.

The control program of automatic pump swash plate control mechanism 31D constitutes, control is advanced with Proportional valve 36 or laggard action with Proportional valve 37, thereby come operating pumps swash plate 16A with the object run speed that the second service speed setting device 31E sets, thus, can carry out good load control by having considered engine speed change speed, change regardless of the pace of change of engine speed, the sense that resets when decline sense in the time of engine speed can both being reduced or engine speed are recovered keeps constant, but also the reduction of engine speed relatively, responsiveness is carried out the deceleration-operation of pump swash plate 16A well, prevents that pump swash plate 16A from postponing the engine stall that operation causes.

And pace of change feeler mechanism 53 comprises turn-sensitive device 47 and for based on the pace of change of the detection computations engine speed of this turn-sensitive device 47 and the operation program that has in the second service speed setting device 31E.

Has control program among the 31C of data change mechanism, its change automatic pump swash plate control mechanism 31D and the employed map datum of the second service speed setting device 31E, the 31C of data change mechanism constitutes, according to the detection of setting turn-sensitive device 52, the setting rotating speed that the employed map datum of automatic pump swash plate control mechanism 31D is changed to motor 1 is more little, operation amount with respect to the pump swash plate 16A of engine speed change amount becomes big so that the operating position corresponding map data (with reference to figure 9) of engine speed and pump swash plate 16A more, and, detection according to secondary speed change sensor 45, when the speed change level of gear type speed change gear 11 is in low speed side, in order to make the speed change level of gear type speed change gear 11 the closer to low speed side, the operation of pump swash plate 16A is promptly carried out more, and the decline that the employed map datum of automatic pump swash plate control mechanism 31D is changed to according to the speed change level of gear type speed change gear 11 accelerates so that the service speed corresponding map data of the pace of change of engine speed and pump swash plate 16A the service speed of the pump swash plate 16A corresponding with the pace of change of engine speed.

Promptly, data are suitable for the load control of the setting rotating speed of motor 1 according to the map, so irrelevant with the setting rotating speed of motor 1, can prevent well that the engine stall that causes because of overload, above-mentioned map datum from having considered the setting rotating speed of the motor 1 selected according to the setting rotating speed of motor 1.

In addition, speed change level according to gear type speed change gear 11, and adopt with this speed change level the closer to low speed side, the map datum that the mode that accelerates more with respect to the service speed of the pump swash plate 16A of the pace of change of engine speed is set, even so engine speed is reduced because of the bigger operation of operation load suddenly, also can responsiveness well and promptly carry out the deceleration-operation of pump swash plate 16A, the result can prevent more reliably that because of overload produces to stall described gear type speed change gear 11 is carrying out the sort of degree low speed side of the bigger operation of operation load by variable speed operation.

And, although omitted diagram, but can comprise: the manually operated type service speed setting device (service speed setting device) that constitutes by the potentiometer of when load is controlled, setting pump swash plate 16A object run speed or switch etc., come operating pumps swash plate 16A with the object run speed that sets by this service speed setting device, automatic pump swash plate control mechanism 31D is controlling and is advancing with Proportional valve 36 or laggard action with Proportional valve 37, and sets the object run speed of the pump swash plate 16A that has considered the operation load according to the difference of the apparatus for work kind of connect setting.

In addition, can be in the 31C of data change mechanism, the data change instruction operation piece (instruction mechanism) that is made of potentiometer or switch is being set in taking Drive Section 8, be used to instruct the change of automatic pump swash plate control mechanism 31D or the employed map datum of the second service speed setting device 31E, thus according to connect the apparatus for work that is provided with kind map datum is changed.

In this tractor, being provided with can be with the switching mechanism 54 of the swash plate of variable capacity motor 17 (below, be called motor swashplate) 17A handover operation to the height two-stage.

Switching mechanism 54 comprises: the hydraulic type motor cylinder 55 of operation motor swashplate 17A, the Control work oil phase is to the switching valve 56 that flows of this motor cylinder 55, operate the control valve 57 of the electromagnetic type of this switching valve 56, can supply with the high selector relay 58 of working oil from the closed-loop path 20 of static oil pressure endless gearing device 10 to this control valve 57, be located at the changer lever 59 of steering wheel 6 left bottoms, the bar sensor 60 that constitutes by the switch that detects these changer lever 59 operating positions, and be included in motor swashplate control mechanism 31F in the control mechanism 31 etc. as the control program that carries out the height handover operation of motor swashplate 17A according to the detection of bar sensor 60.

Motor cylinder 55 and variable capacity motor 17 are contained among the second housing section 4B of gearbox 4 in removably.

Motor swashplate control mechanism 31F is according to the detection of bar sensor 60, when changer lever 59 is operated low-speed position, carry out the height switching controls from the high speed position handover operation to low-speed position with motor swashplate 17A, open corresponding display lamp 61 simultaneously, in addition, when changer lever 59 is operated high speed position, carry out the low high switching controls from the low-speed position handover operation to high speed position with motor swashplate 17A, open corresponding display lamp 62 simultaneously.

Promptly, when the climbing that changer lever 59 is set in high speed position is travelled or operation make under the situation that travelling speed significantly reduces because of the load of travelling increases when travelling, can be by changer lever 59 be switched to low-speed position from high speed position, increase is to the driving force of left and right sides front-wheel 3 and left and right sides trailing wheel 5, thereby can proceed that climbing is travelled or operation is travelled.

And, be located on the operation panel 63 of steering wheel 6 belows display lamp 61,62 is being set.

Motor swashplate control mechanism 31F is when its height switching controls, at first according to the detection of swash plate sensor 30, the current operating position of storage pump swash plate 16A, and the deceleration object run position of calculating pump swash plate 16A, till arriving this deceleration object run position that calculates, control is advanced with Proportional valve 36 or laggard action with Proportional valve 37, so that pump swash plate 16A deceleration-operation is arrived predetermined service speed, after pump swash plate 16A arrives deceleration object run position, control is advanced with Proportional valve 36 or laggard with the action of Proportional valve 37 and the action of control valve 57, so that can carry out simultaneously: pump swash plate 16A operates and with scheduled operation speed motor swashplate 17A is switched to from high speed position the handover operation (with reference to figure 10A) of low-speed position to the recovery speedup of the operating position of storage with scheduled operation speed.

In addition, when it hangs down high switching controls, at first according to the detection of swash plate sensor 30, the current operating position of storage pump swash plate 16A, the deceleration object run position of calculating pump swash plate 16A, control is advanced with Proportional valve 36 or laggard with the action of Proportional valve 37 and the action of control valve 57, so that can carry out simultaneously: pump swash plate 16A with scheduled operation speed to the deceleration-operation of the deceleration object run position of calculating with motor swashplate 17A is switched to the handover operation of high speed position with scheduled operation speed from low-speed position, after this, control is advanced with Proportional valve 36 or laggard action with Proportional valve 37, so that, pump swash plate 16A is recovered speedup operation (with reference to figure 10B) with scheduled operation speed till the operating position of storage.

Promptly, with motor swashplate 17A when high speed position switches to low-speed position, by carrying out speedup operation and the handover operation of pump swash plate 16A simultaneously, just can make along with the volume change of the variable displacement pump 16 that is produced with the volume change of the variable capacity motor 17 that handover operation produced of motor swashplate 17A from the high speed position handover operation to low-speed position with along with the speedup operation of pump swash plate 16A is cancelled out each other, in addition, at motor swashplate 17A when low-speed position switches to high speed position, by carrying out deceleration-operation and the handover operation of pump swash plate 16A simultaneously, just can make along with the volume change of the variable displacement pump that deceleration-operation produced 16 of volume change from the low-speed position handover operation to the variable capacity motor 17 that high speed position produced and pump swash plate 16A with motor swashplate 17A is cancelled out each other, thereby the speed change that handover operation produced that can relax because of motor swashplate 17A shakes.

And, although do not illustrate among the figure, can also adopt the high-speed response valve to replace switching valve 56, motor swashplate control mechanism 31F is when carrying out handover operation to motor swashplate 17A, reduce the service speed of motor swashplate 17A by load (duty) control high-speed response valve, slow down the volume change of the variable capacity motor 17 that produces when motor swashplate 17A switches, thereby relax the speed change vibrations that variable capacity motor 17 volume change cause.

And, motor swashplate 17A is being switched under the travelling state of high speed position, also can be according to the detection of braking sensor 49, the brake operating of motor swashplate control mechanism 31F and braking device is carried out the height switching controls with linking, thereby improve braking.

In addition, motor swashplate control mechanism 31F constitutes, motor swashplate 17A is being switched under the travelling state of high speed position, detection according to pedal sensor 29 and swash plate sensor 30, to carry out deceleration-operation irrelevant with gear shift pedal 24 detecting, advance retarding spring 32 or laggard retarding spring 33 when all pump swash plate 16A not being carried out deceleration-operation, can carry out the height switching controls, reasons such as inertia during because of the tractor operation, in that to carry out deceleration-operation irrelevant with gear shift pedal 24, when pump swash plate 16A does not carry out deceleration-operation, can carry out deceleration-operation by the height switching controls.

And then, motor swashplate control mechanism 31F constitutes, can switch under the state of high speed position at motor swashplate 17A, detection according to service speed feeler mechanism 46, when the service speed of gear shift pedal 24 is faster than scheduled operation speed, carry out the height switching controls, thereby prevent to start suddenly or quicken suddenly.

As shown in Figure 1, near the mode that changer lever 59 is positioned at the operating end left part of steering wheel 6 is extended setting, hand departure direction dish 6 just can need not be carried out the height handover operation to motor swashplate 17A thus.In addition, in tractor, connect when front-end loader A (with reference to figure 6) is being set, hand need not be left the operating stem (not shown) of the front-end loader that is located at steering wheel 6 right sides, just can carry out the height handover operation motor swashplate 17A.

Shown in Fig. 4～6, in control mechanism 31, has automatic motor swash plate control mechanism 31G as control program, can followingly constitute: in detection based on pedal sensor 29, when detecting gear shift pedal 24 and operating scheduled operation position or operating area, according to motor 1 Maximum Torque output characteristics and the motor slippage calculated by the operation program of automatic pump swash plate control mechanism 31D, when detecting engine speed and be reduced near the predetermined Maximum Torque output speed height speed-changing or height speed-changing zone corresponding to gear shift pedal 24 operating positions of this moment, carry out automatically the height switching controls with motor swashplate 17A from the high speed position handover operation to low-speed position, simultaneously corresponding display lamp 61 is opened; In addition, in slippage according to motor, detect engine speed and rise near the desired speed low high speed-changing or low high speed-changing when regional, detection based on pedal sensor 29, when detecting gear shift pedal 24 and operating scheduled operation position or operating area, carry out low automatically high switching controls motor swashplate 17A is switched to high speed position from low-speed position, simultaneously corresponding display lamp 62 is opened.

Specifically, constitute, for example maximum is being scrunched the position as 100% and the operating position of pedal 24 is under the situation of the operating position below 50%, along with setting rotating speed as 100% and engine speed is reduced to 85% rotating speed, in addition, maximum is being scrunched the position as 100% and the operating position of pedal 24 is under the situation of the operating position more than 90%, along with setting rotating speed as 100% and engine speed is reduced to 70% rotating speed, carry out height switching controls automatically, and constitute, to set rotating speed as 100% and engine speed rises under the situation of the rotating speed more than 90%, along with maximum being scrunched the position as 100% and the operating position of pedal 24 is the operating position more than 80%, carry out low automatically high switching controls.

Promptly, gear shift pedal 24 scrunch operation amount when increasing the motor slippage must strengthen, the motor that can produce when operation amount reduces to a certain degree that scrunches of gear shift pedal 24 descends simultaneously, if increase the amount of scrunching of gear shift pedal 24, the state that just can judge this moment is in the also very big heavy condition of motor slippage, even therefore reducing the motor slippage also can carry out the height switching controls and guarantee driving force, therefore, even the driver has not considered the variable speed operation of operation load etc., also can prevent engine stall, thereby need can proceed the heavily loaded operation of high drive because of the overload generation.In addition, when near the load engine speed rises to predetermined setting rotating speed reduces, occurring under the situation that the driver thinks faster acceleration, hang down high switching controls and improve the speed of a motor vehicle, therefore can prevent following problems, that is, although reducing along with load, the driver reduces the amount of scrunching of gear shift pedal 24 and wants slows down, but hangs down high switching controls and unforeseen acceleration takes place.

In the height switching controls of automatic motor swash plate control mechanism 31G, when carrying out the stage of this handover operation, because of reducing the speed of a motor vehicle greatly, the load of travelling supposes that the speed change vibrations are less, therefore do not carrying out the such control that is used for the speed change vibrations of height switching controls by motor swashplate control mechanism 31F, and control is advanced with Proportional valve 36 or laggard action with Proportional valve 37, so that with predetermined service speed with motor swashplate 17A from the high speed position handover operation to low-speed position, after motor swashplate 17A is switched to low-speed position, this state is kept preset time (for example about 2 seconds).

In addition, in the low high switching controls of automatic motor swash plate control mechanism 31G, the identical control action of low high switching controls that is carried out with motor swashplate control mechanism 31F, slow down the speed change that low high handover operation produced vibrations because of motor swashplate 17A, after motor swashplate 17A is switched to high speed position, this state is kept preset time (for example about 2 seconds).

And, also automatic motor swash plate control mechanism 31G can be constituted, along with according to the Maximum Torque output characteristics of motor 1 and the motor slippage of calculating by the operation program of automatic pump swash plate control mechanism 31D, detect and be reduced near height speed-changing of predetermined Maximum Torque output speed or height speed-changing zone, and carry out automatically the height switching controls and motor swashplate 17A is switched to low-speed position from high speed position, simultaneously corresponding display lamp 61 is opened; In addition, along with slippage according to motor, detect engine speed and rise near low high speed-changing of desired speed or low high speed-changing zone, and carry out low automatically high switching controls motor swashplate 17A is switched to high speed position from low-speed position, simultaneously corresponding display lamp 62 is opened.

In control mechanism 31, comprise the 31H of mode switching mechanism as control program, the 31H of this mode switching mechanism is according to switching the control mode of execution by the operation of the mode setting device that normal open switch constituted 64 that has in the display floater 63.The pressing operation of this 31H of mode switching mechanism adjoint mode setting device 64 and import opening signal, the speed Control mode switching of carrying out is arrived manual control mode, semiautomatic control pattern and automatic control mode, open display lamp 65～67 simultaneously corresponding to each control mode, and in manual control mode, utilize pump swash plate control mechanism 31A control action speed of a motor vehicle control and utilize the switching controls of the control action of motor swashplate control mechanism 31F; In the semiautomatic control pattern, the load control of the control action that the mode of preferentially carrying out load control with the control of the relative speed of a motor vehicle carries out speed of a motor vehicle control that pump utilizes the control action of swash plate control mechanism 31A, utilize motor swashplate control mechanism 31D and utilize the switching controls of the control action of motor swashplate control mechanism 31F; In automatic control mode, utilize with following state the control action of pump swash plate control mechanism 31A speed of a motor vehicle control, utilize motor swashplate control mechanism 31D control action load control and utilize the automatic switchover control of the control action of automatic motor swash plate control mechanism 31G, that is, speed of a motor vehicle control is preferentially carried out load control and load control is connected with suitable linkage manner with the control of automaticallying switch relatively.

Promptly, when selecting manual control mode, according to operating position of gear shift pedal 24 etc., 16A operates to the pump swash plate, so that arrive and the corresponding object run of the operating position position of gear shift pedal 24, and motor swashplate 17A is carried out the just handover operation of two positions according to the operation of changer lever 59 with object run speed; And when selecting the semiautomatic control pattern, operating position according to gear shift pedal 24 is operated pump swash plate 16A, so that arrive and the corresponding object run of the operating position position of gear shift pedal 24 with object run speed, on the other hand, when producing motor decline, operate according to motor slippage etc., so that arrive and the corresponding boundary operating position of motor slippage, and motor swashplate 17A is carried out the handover operation of height two positions according to the operation of changer lever 59 with object run speed; When selecting automatic control mode, according to operating position of gear shift pedal 24 etc. pump swash plate 16A is operated, so that arrive and the corresponding object run of the operating position position of gear shift pedal 24 with object run speed, on the other hand, when producing motor decline, operate according to motor slippage etc., so that reach and the corresponding boundary operating position of motor slippage with object run speed, and according to the operating position or the motor slippage of gear shift pedal 24, is the height two positions on suitable opportunity with motor swashplate 17A handover operation, thus, if for example moving when travelling or selecting manual control mode during the underload operation, select the semiautomatic control pattern when the bigger climbing of the gradient is travelled or during the medium load operation, select automatic control mode when the big climbing of the gradient is travelled or during the heavy duty operation, then can reduce driver's burden, travel well and operation.

Simultaneously, the decline boundary rotating speed of the motor 1 that the load control of the load control ratio semiautomatic control pattern of automatic control mode is set is lower, thus, the control sensitivity just is set to such an extent that be insensitive to the decline of generation motor, and the automatic switchover that therefore just is easy to carry out motor swashplate 17A switches on the low-speed position is controlled.

In addition, under the state of selecting automatic control mode, in operation according to changer lever 59, carry out motor swashplate 17A under the situation of the handover operation of low-speed position, do not carry out controlling the switching controls of motor swashplate 17A to low-speed position by automaticallying switch, control mode will automatically switch to the semiautomatic control pattern from automatic control mode.

As shown in Figure 6, liquid crystal display 69 is being set on operation panel 63, it can be according to the operation that shows diverter switch 68, switch show states such as speed of a motor vehicle show state or residual fuel show state, if this liquid crystal display 69 is according to the operation that shows diverter switch 68, select pump swash plate positions display mode, then show object run position 69A or boundary operating position 69B and the current location 69C of the pump swash plate 16A that changes constantly.

That is,, can determine the action of pump swash plate 16A easily, thereby improve maintainability by selecting pump swash plate positions display mode.

Simultaneously, the state of the object run position 69A of speedup has been set in Figure 11 (A) expression to pump swash plate 16A, the state that Figure 11 (B) expression pump swash plate 16A operates towards the object run position 69A that speedup is used, the object run position 69A of the deceleration usefulness of Figure 11 (C) expression pump swash plate 16A or the state that boundary operating position 69B is set.

The 31C of data change mechanism constitutes, operatively be connected with at lifting under the job state of apparatus for work of front-end loader A etc., under the situation of the height sensor 70 that the potentiometer that is provided with by the height and position that detects this apparatus for work constitutes, along with detection according to height sensor 70, lift operations on the apparatus for work to the height and position more than the predetermined altitude height and position of overall height (for example surpass), is changed to storage with the map datum of the dependency relation between the operating position of the operating position of the employed expression gear shift pedal 24 of pump swash plate control mechanism 31A and pump swash plate 16A and is arranged on the map datum of using when apparatus for work among the pump swash plate control mechanism 31A rises.

The map datum of using when apparatus for work rises is compared with normally used map datum, it is the operating position of relative gear shift pedal 24, the operating position of pump swash plate 16A is arranged on the map datum (with reference to figure 7) of low speed side, by making pump swash plate control mechanism 31A use this map datum, and with vehicle-speed limit at low speed side, stop under apparatus for work rises to unstable state more than the setting height and run at high speed.

As Fig. 4, shown in 5, in servo-control mechanism 25, servovalve 27, modulating valve 28, swash plate sensor 30 and oil temperature sensor 43 all are located in the housing 71, the unit changes into a module as electronic type operating device 72, described housing 71 is detachably connected on the right side of the second housing section 4B in the gearbox 4 by bolt, as Figure 12, shown in 13, also this electronic type operating device 72 can be replaced with the mechanical actuator 76 that the unit changes into a module, from electronic type simply form change to mechanical type, described mechanical actuator 7 will be operationally connected to the service axis 73 on the gear shift pedal 24 and by the Control work oil phase servovalve that guiding valve constituted 74 that flows of pumping cylinder 26 etc. will be located in the housing 75 by mechanical type bindiny mechanism (not shown), and described housing is detachably connected on the right side of the second housing section 4B in the gearbox 4 by bolt.

And, Fig. 4 and reference character 77 expression link arms shown in Figure 12, this link arm is in electronic type servo-control mechanism 25, as spreading all over the feedback arm use that pumping cylinder 26 and swash plate sensor 30 set up, and in mechanical type servo-control mechanism 78, in order to operate servovalve 74, as spreading all over the dual-purpose arm of operational feedback that pumping cylinder 26 and service axis 73 set up.

And, at 78, the 79 expression connecting ports of the reference character shown in Fig. 5 and Figure 13, this connecting port is on the right side that electronic type operating device 72 is connected to the second housing section 4B with bolt the time, with corresponding to the second housing section 4B be formed on each connecting port 80,81 on the mating face with housing 71 and ways of connecting, be formed on housing 71 and the face that the second housing section 4B engages.

Shown in Fig. 4,5, in switching mechanism 54, be contained in the housing 83 in switching valve 56, control valve 57 and the high selector relay 58, the unit changes into a module as operating device 84, and described housing 83 is detachably connected on the left side of the second housing section 4B in the gearbox 4 by bolt.Shown in Figure 12,14, this operating device 84 replaced with plate 85 and block each connecting port 86～91 that on the second housing section 4B and face that operating device 84 engages, forms, and the variable capacity motor 17 in the second housing section 4B is replaced with fixed capacity motor 92 and dismantles pumping cylinder 55, thereby just can become the fixing motor form from variable motor form fairly simplely.

And, reference character 93～98 expression connecting ports shown in Fig. 5, this connecting port is on the left side that switching mechanism 54 is connected to the second housing section 4B with bolt the time, with ways of connecting, be formed on housing 83 and the face that the second housing section 4B engages corresponding to each connecting port 86～91 of the second housing section 4B.

Therefore, from said structure, structure (with reference to figure 5) with electronic type servo-control mechanism 25 is arranged in variable motor form, structure (with reference to Figure 13) with mechanical type servo-control mechanism 78 is arranged in variable motor form, structure (with reference to Figure 14) with electronic type servo-control mechanism 25 is arranged in the fixing motor form, structure (with reference to Figure 15) with mechanical type servo-control mechanism 78 is arranged in the fixing motor form, the form change can be between above-mentioned various structures, carried out simply, and the reduction of cost and the facilitation of part management etc. can be realized owing to the generalization of part.

As shown in Figure 6, the zone of the operating area both end sides of gear shift pedal 24 can be set at high-speed region, be set at low-speed region with between them, motor swashplate control mechanism 31F can be according to the detection of pedal sensor 29, when gear shift pedal 24 was operated into low-speed region, 17A switched to low-speed position with motor swashplate; And when gear shift pedal 24 is operated into high-speed region, 17A switches to high speed position with motor swashplate, thereby control the action of above-mentioned control valve 57, gear shift pedal 24 is used for the operation piece of the height two positions switching usefulness of variable capacity motor 17, in addition, also the zone of the both end sides of the operating area of gear shift pedal 24 can be set at high-speed region, motor swashplate control mechanism 31F can be according to the detection of pedal sensor 29, when gear shift pedal 24 is operated into high-speed region, 17A switches to high speed position with motor swashplate, thereby control the action of above-mentioned control valve 57, gear shift pedal 24 is used for the low high operation piece that switches usefulness of variable capacity motor 17.

Gear shift pedal 24 is being used for the switching of switching variable capacity motor 17 when using operation piece like this, the ratchet mechanism (not shown) of the boundary that is used to hold gear shift pedal 24 operating areas also can be set.

Below, other mode of executions of the present invention are described with reference to the accompanying drawings.

The part of having narrated here just no longer repeats.

As shown in figure 16, with the gear shift pedal 110 that is located on the Drive Section, but the mechanical linkage which controls 111 of operation hawser by utilizing the push-and-pull transmission or linkage rod etc., and with operating stem 112a interlock as the acceleration mechanism 112 of the speed regulating mechanism of above-mentioned motor 1.Make the setting engine rotation speed sensor 113 that is located on the above-mentioned acceleration mechanism 112, be located at practical engine speeds sensor 114 on the above-mentioned motor 1 and the variable speed operation sensor 115 (operating position feeler mechanism) of above-mentioned gear shift pedal 110 interlocks all is connected with control mechanism 116, in this control mechanism 116, also connecting the shifting actuator 117 and the stroke sensor 118 that are provided with on the above-mentioned stepless speed changes devices 108 simultaneously.

At gear shift pedal 110 from neutral position operation during when advancing the zone or from neutral position operation to the back recessed region, the operating stem 112a that above-mentioned linking mechanism 111 will speed up mechanism 112 to high-speed side, and makes gear shift pedal 110 and operating stem 112a interlock from the idle position swinging operation.

Setting engine rotation speed sensor 113 is made of the potentiometer of the operating stem 112a interlock of service axis and acceleration mechanism 112, and the operating position according to operating stem 112a detects the setting engine speed that the engine speed that should occur as motor 1 is passed through acceleration mechanism 112 settings, should output in the control mechanism 116 as electrical signal by detected setting engine speed A.

Practical engine speeds sensor 114 is made of the turn-sensitive device that the output shaft (not shown) with motor 1 links, and detects the actual speed of motor 1, should output in the control mechanism 116 as electrical signal by detected practical engine speeds E.

Variable speed operation sensor 115 is made of the potentiometer of the rotation fulcrum 110a interlock of service axis and gear shift pedal 110, and detect the operating position of operating pedal 110 according to the rotational position of rotation fulcrum 110a, should output in the control mechanism 116 as electrical signal by detected operating position H.

The interlock of the swash plate service axis (not shown) of the oil pump 108a of shifting actuator 117 and stepless speed changes devices 108, the swash plate by rotary manipulation oil pump 108a comes stepless speed changes devices 108 is carried out variable speed operation.

The swash plate service axis interlock of stroke sensor 118 (swash plate positions feeler mechanism) and oil pump 10ga, detect stepless speed changes devices 108 according to the swash plate angle and whether be in what kind of shift position (operating position), should output in the control mechanism 116 as electrical signal by detected shift position F.That is, the operating position of the swash plate velocity location F that can be used as stepless speed changes devices 108 understands.Therefore, when setting the target velocity of stepless speed changes devices 108, this swash plate will be towards the operating position operation corresponding to the target velocity of its setting.

Control mechanism 116 utilizes microcomputer to constitute, and as Figure 18,19,20 described actions.

That is, as shown in figure 18, control mechanism 116 judges according to the detection information that variable speed operation sensor 115 obtains whether gear shift pedal 110 is operated.If judge that gear shift pedal 110 has been operated, then according to setting the detection information that engine rotation speed sensor 113 and practical engine speeds sensor 114 obtain, calculate and detect the difference of setting between engine speed A and the detection practical engine speeds E, according to this difference D, judge to detect and set engine speed A and detect between the practical engine speeds E whether have difference.If this difference D is less than setting difference D0 (200rpm), then judge to detect to set engine speed A and detect between the practical engine speeds E and do not have difference, if this difference D that calculates is setting more than the difference D0 (200rpm), then judge to detect to set engine speed A and detect between the practical engine speeds E to have difference.If judging to detect to set engine speed A and detect between the practical engine speeds E does not have difference, then by the speed Control of common speed Control execution to stepless speed changes devices 108 variable speed operations; If detection is set engine speed A and detected between the practical engine speeds E difference is arranged, then by revising the speed Control of speed Control execution to stepless speed changes devices 108 variable speed operations; If stroke sensor 118 detected variable speed operation state F be in the detected corresponding detection variable speed operation of the operating position H state of variable speed operation sensor 115 under, then stop the variable speed operation of stepless speed changes devices 108.

As shown in figure 19, when carrying out the variable speed operation of stepless speed changes devices 118 by common speed Control, control mechanism 116 is set in the operating position of shifting actuator 117 according to the detection information of variable speed operation sensor 115 and usually on the corresponding position of control target speed VH, by operation shifting actuator 117, the detection shift position F of stroke sensor 118 is in and usually on the corresponding position of control target speed VH, stepless speed changes devices 108 just operate with the corresponding position of common control target speed VH on move.

As shown in figure 20, when carrying out the variable speed operation of stepless speed changes devices 108 by the correction speed Control, control mechanism 116 according to the detection information of variable speed operation sensor 115 with the operating position of shifting actuator 117 be set in the corresponding position of Correction and Control target velocity VL on, by operation shifting actuator 117, make the detection shift position F of stroke sensor 118 be in the corresponding position of Correction and Control target velocity VL on, stepless speed changes devices 1 08 just operate with the corresponding position of Correction and Control target speed VL on move.

Control mechanism 116 is set common control target speed VH and Correction and Control target velocity VL according to map shown in Figure 17.

Promptly, common control target speed VH and Correction and Control target velocity VL can be set: if the operating position (angle) that will detect the swash plate when setting engine speed A and detecting difference D between the practical engine speeds E less than 200rpm is as 100, when then the difference D between detection setting engine speed A and the detection practical engine speeds E is 800rpm, the work angle of swash plate is 60, difference D between detection setting engine speed A and the detection practical engine speeds E is when 1000rpm is above, and the work angle of swash plate is 20.Therefore, Correction and Control target velocity VL is set than common control target speed VH low speed more.

Promptly, when car body travels, by trampling gear shift pedal 110 in advance zone or back recessed region, linking mechanism 111 is to the operating stem 112a of high-speed side swinging operation acceleration mechanism 112, acceleration mechanism 112 is in the high-speed side action and will set the engine speed change setting to high-speed side, simultaneously, control mechanism 116 is operated shifting actuator 117 stepless speed changes devices 108 variable speed operations is arrived high-speed side according to the detection information of variable speed operation sensor 115.Thus, can improve engine speed and with stepless speed changes devices 108 speed changes to the mode of the speed change state of the corresponding high-speed side of engine speed motor 1 being linked to each other with stepless speed changes devices 108 and carrying out the speedup operation, improve car body and travel in the travelling speed of advance side or laggard side.

At this moment, carry out rotation speed change in motor 1 good response in the action of acceleration mechanism 112, engine speed rises to and equals or when being substantially equal to the setting engine speed of 112 change settings of acceleration mechanism, control mechanism 116 is according to the detection information of setting engine rotation speed sensor 113 and practical engine speeds sensor 114, judge that detecting the difference D that sets engine speed A and detect between the practical engine speeds E does not have or roughly do not have, and set common control target speed VH according to the detection information of this judged result and variable speed operation sensor 115, stepless speed changes devices 108 is operated so that make stepless speed changes devices 108 with the corresponding position of common control target speed VH on operate.Relative therewith, can good response not carry out rotation speed change at motor 1 in the action of acceleration mechanism 112, engine speed does not rise to and equals or when being substantially equal to the setting engine speed of 112 change settings of acceleration mechanism, control mechanism 116 is according to the detection information of setting engine rotation speed sensor 113 and practical engine speeds sensor 114, judge whether detect the difference D that sets engine speed A and detect between the practical engine speeds E exists, and according to the detection information setting of this judged result and variable speed operation sensor 115 than the common control target speed VH Correction and Control target velocity VL of low speed more, stepless speed changes devices 108 is carried out variable speed operation, so that with on stepless speed changes devices 108 operations and the corresponding position of Correction and Control target velocity VL.

Thus, in the operation of trampling along with gear shift pedal 110, no matter whether acceleration mechanism 112 moves to high-speed side, engine speed do not rise to setting engine speed that acceleration mechanism 112 sets or roughly near engine speed the time, compare engine speed rise to setting engine speed that acceleration mechanism 112 sets or roughly near engine speed the time, variable speed operation stepless speed changes devices 108 just under lower-speed state only, thereby the load that is applied on the motor 1 is lightened and can not produce to stall, engine speed rises to the setting engine speed that acceleration mechanism 112 sets in the early stage the time car body is travelled simultaneously.

Adopt speed change lever even substitute gear shift pedal 110, also can realize purpose of the present invention.Therefore, gear shift pedal 110 or speed change lever are referred to as variable speed operation spare.

Below, other mode of execution is described.

Figure 21 is the block diagram of the mobility operation device that has of tractor.As shown in the figure, the mobility operation device comprises: the oil pressure speed change cylinder 226 of the above-mentioned stepless speed changes devices 210 of variable speed operation (below abbreviate speed change cylinder 226 as.), the electric actuator 241 of the accelerating unit 240 of the above-mentioned motor 1 of operation (below abbreviate as and quicken actuator 241.) control mechanism 221 that links to each other and link to each other with above-mentioned acceleration actuator 241 with the servo-control mechanism 220 of controlling above-mentioned speed change cylinder 226.In addition, the mobility operation device also comprises: be located at gear shift pedal 224 on the Drive Section and accelerator rod 225, as the operating position that detects above-mentioned gear shift pedal 224 and should detection information output to the sensor on the above-mentioned control mechanism 221 revolving potentiometer 227 (below be called pedal sensor 227.), as the operating position that detects above-mentioned accelerator rod 225 and should detection information output to the sensor on the above-mentioned control mechanism 221 revolving potentiometer 228 (below be called accelerator rod sensor 228.)。And then the mobility operation device also comprises: make linking mechanism 250 that the operation unit 240a of above-mentioned gear shift pedal 224 and above-mentioned accelerating unit 240 links, by be located on the Drive Section interlock break-make bar 261 with linking mechanism 250 handover operations to the operating device 260 of on-state and off state, as detecting switch 229 operating position that detects above-mentioned interlock break-make bar 261 and that should detection information output to the sensor in the above-mentioned control mechanism 221 (below be called break-make sensor 229.)。

As shown in figure 21, above-mentioned servo-control mechanism 220 comprises advance proportional control valve 231 and laggard proportional control valve 232, this advance proportional control valve 231 and laggard proportional control valve 232 be by carrying out handover operation from the instruction of control mechanism 221, operation speed change cylinder 226 so that stepless speed changes devices 210 become and the corresponding speed change state of the operating position of gear shift pedal 224.This servo-control mechanism 220 is installed in the above-mentioned transmission case 4B.

Above-mentioned control mechanism 221 utilizes microcomputer to constitute, based on the detection information of above-mentioned pedal sensor 227 and the detection information of swash plate sensor 234, operate speed change cylinder 226 by servo-control mechanism 220, stepless speed changes devices 210 is become and the corresponding speed change state of the operating position of gear shift pedal 224, and described swash plate sensor 234 can detect the speed change state of stepless speed changes devices 210 according to above-mentioned swash plate angle.

Control mechanism 221 is according to the detection information of above-mentioned break-make sensor 229, judge that above-mentioned linking mechanism 250 is on-state or off state, when judging that linking mechanism 250 is in off state, according to the detection information of accelerator rod sensor 228 and the detection information of the acceleration sensor 235 of the serviceability that detects accelerating unit 240, operate and quicken actuator 241, make accelerating unit 240 be in these serviceability, promptly in motor 1, produce and the corresponding rotating speed of operating position of accelerator rod 225.Relative therewith, judging that linking mechanism 250 is under the on-state, control mechanism 221 stops to quicken the operation of actuator 241 according to the detection information of accelerator rod sensor 228 and acceleration sensor 235, and make and quicken actuator 241 and be in the state that to operate by external force, thereby operate accelerating unit 240 by above-mentioned gear shift pedal 224.

When tractor travels, operate the car body front side if gear shift pedal 224 is trampled from neutral condition by front side operation unit 224a (with reference to Figure 22,24), then control mechanism 221 is operated advance side with speed change cylinder 226, to advance side, make tractor to overtake stepless speed changes devices 210 variable speed operations.Operate the car body rear side if gear shift pedal 224 is trampled from neutral condition by rear side operation unit 224a (with reference to Figure 22,24), then control mechanism 221 is operated laggard side with speed change cylinder 226, stepless speed changes devices 210 variable speed operations to laggard side, are made that tractor is laggard to travel.No matter be to travel to overtake or backward, gear shift pedal 224 to trample stroke big more, control mechanism 221 more speed change cylinder 226 is operated high-speed side and with stepless speed changes devices 210 variable speed operations to higher high-speed side, thereby improve the travelling speed of tractor.

Like this, when tractor travelled, under the situation of travels down, the break-make that will link bar 261 switched on positi ON place.So, make linking mechanism 250 become on-state by the effect of operating device 260, thereby make gear shift pedal 224 and accelerating unit 240 interlocks.Thus, trample operation during gear shift pedal 224, linking with it and make accelerating unit 240 move the speedup side, thereby improving the rotating speed of motor 1.Improve trampling stroke and strengthening stepless speed changes devices 210 of gear shift pedal 224 more, make accelerating unit 240 in higher high-speed side action more, thereby further improve engine speed to the high-speed side variation.Thus,, also can improve engine speed, can not produce to stall even when running at high speed.On the other hand, in the operation of removing gear shift pedal 224, when the reset operation that the positioning means 270 that has on the gear shift pedal 224 is produced is operated low speed side with gear shift pedal 224, link with it and make accelerating unit 240 move deceleration side.Thus, if low speed driving just can make the rotating speed of motor 1 reduce and reduce fuel consumption.

Relative therewith, when operation was travelled, the break-make bar 261 that will link in advance switched to off position OFF place.So, make linking mechanism 250 become off state by the effect of operating device 260, the interlock between gear shift pedal 224 and the accelerating unit 240 is disconnected.Thus, even gear shift pedal 224 is trampled operation, reset operation is to low speed side, and accelerating unit 240 also can keep the speed state that set by accelerator rod 225.Therefore, even travelling speed changes, the rotating speed of motor 1 is also constant, and the apparatus for work that links to each other also can keep the driving rotating speed be scheduled to.

Figure 22 is the side view of the included above-mentioned positioning means 270 of gear shift pedal 224.Figure 25 is the stereogram of the part of positioning means 270.As shown in these figures, positioning means 270 comprises force application mechanism 274 and the rotary damper 281 that links to each other with a side of the rotation fulcrum 280 of gear shift pedal 224, above-mentioned force application mechanism has a distolateral helical spring 273 that is bearing on the spring bracket 272 that matrix 271 had, and above-mentioned matrix 272 is fixed on Drive Section floor lower face side.

Force application mechanism 274 also comprises except having above-mentioned spring 273: can be bearing in rotary component 275 on the axle 271a of above-mentioned matrix 271 freely by the 275a of connecting cylinder portion rotation; The linkage rod 276 that links to each other with connecting sheet 224a, described connecting sheet 224a makes the end of the arm 275b of this rotary component 275 be positioned at the rear end of gear shift pedal 224; Can be bearing in location swing member 278 on the fulcrum 271b of above-mentioned matrix 271 freely by the 278a of connecting cylinder portion swing; And be located at cam mechanism 279 between the cam board 275c of another 278b of swing arm portion of above-mentioned location swing member 278 and above-mentioned rotary component 275.A 278c among a pair of swing arm 278b of portion, the 278c of above-mentioned spring 273 and above-mentioned location swing member 278 links to each other.

Shown in Figure 22,25, above-mentioned cam mechanism 279 comprises: be located at the V-arrangement inclined cam surface 279a on the cam board 275c of above-mentioned rotary component 275 and make the roller rotation be bearing in revolving cam follower 279b on the above-mentioned swing arm 278b of portion of above-mentioned location swing member 278 freely.Above-mentioned spring 273 is by making its swing to the above-mentioned swing arm 278c of the portion application of force, and the above-mentioned cam follower 279b application of force is leaned against on the above-mentioned inclined cam surface 279a.

As shown in figure 24, above-mentioned rotary damper 281 comprises: body shell 281a, rotation are contained in the rotor operation body 281c of the rotor 281b of this body shell 281a inside, the damper oil that is contained in aforementioned body housing 281a inside and above-mentioned rotor 281b interlock freely.Body shell 281a is by supporting the above-mentioned rotation fulcrum 280 of above-mentioned gear shift pedal 224 by a pair of longitudinal slice 282a of portion, and is fixed among the aforementioned a pair of longitudinal slice 282a of portion that can swing the supporting body 282 that supports gear shift pedal 224 freely one outer side surface.Rotor operation body 281c be configured to aforementioned rotation fulcrum 280 with the state of core shape rotatable freely with the rotation fulcrum 280 fuse.

That is, no matter gear shift pedal 224 is trampled operation forward or backward from neutral condition, and rotary component 275 all can link with the swing of gear shift pedal 224, rotates around the axle center of fulcrum 271.Like this, by the effect of cam mechanism 279, location swing member 278 rotary manipulations make rotary component 275 reset to initial position.Thus, positioning means 270 is positioned at neutral condition by the elastic restoring force of spring 273 with gear shift pedal 224, and no matter gear shift pedal 224 is still trampled operation forward backward, all gear shift pedal 224 reset operations is arrived neutral condition.And then positioning means 270 applies rotational resistance by 281 pairs of gear shift pedals 224 of rotary damper, so that can promptly not move neutral condition because of spring 273 makes the gear shift pedal 224 of the operation that is reset.

As Figure 23,25, shown in 27, the above-mentioned linking mechanism 250 of gear shift pedal 224 and accelerating unit 240 interlocks is comprised: above-mentioned positioning means 270, swing the acceleration linkage part 251 that is bearing in freely on the above-mentioned fulcrum 271b that supports above-mentioned location swing member 278 by the 251a of connecting cylinder portion, be located at a pair of swing arm 251b of portion that this acceleration linkage part 251 is had, clamping mechanism 252 between the above-mentioned 278c of swing arm portion of a 251b among the 251c and above-mentioned location swing member 278, make the operation cable 253 of the operation unit 240a interlock of above-mentioned another 251c of swing arm portion of above-mentioned acceleration linkage part 251 and accelerating unit 240, with an above-mentioned Returnning spring 254 that the 251c of swing arm portion links to each other that quickens linkage part 251.

Quicken linkage part 251 with near and be bearing on the above-mentioned fulcrum 271b away from the mode of location swing member 278 with being free to slide.Above-mentioned clamping mechanism 252 comprises: set pin-and-hole 252a on the 278c of swing arm portion of position swing member 278, be installed in the set bar 252b in the 251b of swing arm portion that quickens linkage part 251 in order to insert this pin-and-hole 252a.

Figure 27 is the plan view of above-mentioned clamping mechanism 252 disengaged positions, and Figure 28 is the plan view of above-mentioned snap-in structure 252 fastening states.As shown in these figures, that is, if quicken linkage part 251 along fulcrum 271b slide so that near location swing member 278, then set bar 252b will be inserted among the pin-and-hole 252a.Like this, clamping mechanism 252 just becomes the fastening state that is meshed, and makes location swing member 278 and quickens the swing of linkage part 251 one.On the other hand, if quicken linkage part 251 along fulcrum 271b slide so that leave location swing member 278, then set bar 252b will leave pin-and-hole 252a.Like this, clamping mechanism 252 just becomes the disengaged position after the engagement releasing, makes location swing member 278 and quickens linkage part 251 relative swings.

Shown in Figure 23,25,27, aforesaid operations mechanism 260 with above-mentioned linking mechanism 250 handover operation between on-state and off state, except having above-mentioned interlock break-make bar 261, also comprise: the state that is embedded in fulcrum 271b in addition is bearing in operating arm 264 on the above-mentioned matrix 271 freely at the spring 262 between above-mentioned location swing member 278 and the above-mentioned acceleration linkage part 251, by fulcrum 263 swings, the end of interior dress cable 265a is connected to the operation cable 265 on the cable joint 264a of this operating arm 264.

The other end of the interior dress cable of aforesaid operations cable 265 is connected on the above-mentioned interlock break-make bar 261.Above-mentioned spring 262 relative positioning swing membeies 278 to away from a side above-mentioned acceleration linkage part 251 application of forces are made it slide so that the set bar 252b of above-mentioned clamping mechanism 252 leaves from pin-and-hole 252a.Interlock break-make bar 261 is bearing on the supporting body 267 by bar fulcrum 266, axle center that can distaff fulcrum 266, and the guide groove 268a (with reference to Figure 26) of the bar guiding element 268 that is had along supporting body 267 carries out swinging operation.The front end of aforesaid operations arm 264 is provided with rotation roller 264b freely.Operating arm 264 by around the axle center of axle 263 by swinging operation, make the 251c of the swing arm portion butt of above-mentioned roller 264b and above-mentioned acceleration linkage part 251, overcome above-mentioned spring 262 and carry out pressing operation, quicken linkage part 251 near location swing member 278 so that make, perhaps, by the pressing operation of the roller 264b releasing swing arm 251c of portion, make acceleration linkage part 251 carry out the operation of leaving from location swing member 278 by above-mentioned spring 262.

Promptly, if in operating device 260, interlock break-make bar 261 is along guide groove 268a swinging operation, then by operating the pulling force swinging operation operating arm 264 of cable 265, and by this operating arm 264, operate and make its relative positioning swing member 278 approaching quickening linkage part 251 via roller 264b, thus, with clamping mechanism 252 handover operations to fastening state and with linking mechanism 250 handover operations to on-state; Perhaps, the active force by spring 262 is operated its relative positioning swing member 278 is left quickening linkage part 251, thus with clamping mechanism 252 handover operations to disengaged position and with linking mechanism 250 handover operations to off state.

That is, under the situation that gear shift pedal 224 and accelerating unit 240 link, the break-make that will link bar 261 is along guide groove 268a swinging operation, and switches to the on positi ON place that is positioned on guide groove 268a one end.Like this, operating device 260 is operated by 264 pairs of acceleration of operating arm linkage part 251 and is made it near location swing member 278, and makes clamping mechanism 252 switch to fastening state.Thus, linking mechanism 250 is under the on-state, the steering force of gear shift pedal 224 is delivered to the operation unit 240a of accelerating unit 240 just by linkage rod 276, rotary component 275, location swing member 278, set bar 252b, acceleration linkage part 251 and operation cable 253.

At this moment, gear shift pedal 224 is being trampled forward and is being trampled backward when operation, the swaying direction difference of gear shift pedal 224, and turning to of rotary component 275 is also different.But no matter gear shift pedal 224 is trampled operation forward from neutral condition is still trampled operation backward, utilizes inclined cam surface 279a shape role, and location swing member 278 all can be from initial position with identical swaying direction swing, draw operations operation cable 253.Thus, gear shift pedal 224 and accelerating unit 240 link, and make no matter gear shift pedal 224 is still trampled operation forward backward, and the operation unit 240a of accelerating unit 240 can link with trampling of gear shift pedal 224, and swinging operation are to high-speed side.And, at this moment, operate the notch 268b (with reference to Figure 26) of bar guiding element 268 by break-make bar 261 engaging that will link, make interlock break-make bar 261 maintain in the notch 268b and remain on interlock on positi ON place by spring 269, thereby can make linking mechanism 250 remain on on-state.

When gear shift pedal 224 and accelerating unit 240 disconnect interlock, interlock break-make bar 261 is switched to the off position OFF place that is located on the guide groove 268a the other end.Like this, operating device 260 is operated by 262 pairs of acceleration of spring linkage part 251 its relative positioning swing member 278 is left, thereby makes clamping mechanism 252 switch to the state of leaving.Thus, linking mechanism 250 becomes under the off state, and the steering force of gear shift pedal 224 just can not be delivered on the operation unit 240a of accelerating unit 240.

As shown in figure 24, the above-mentioned rotation fulcrum 280 of above-mentioned pedal sensor 227 relative gear shift pedals 224 is arranged on the opposition side of above-mentioned rotary damper 281 sides of living in, and the rotary manipulation axle 27a of pedal sensor 227 is by the opposition side interlock that be connected rotary damper 281 one sides of attachment screw 283 with above-mentioned rotation fulcrum 280.

Figure 29 is the side view of other mode of execution structures of positioning means 270.As shown in the figure, if this positioning means 270 is compared with above-mentioned positioning means 270, then rotary damper 281 be provided with and above-mentioned positioning means 270 different, except the setting of rotary damper 281, all identical with the structure of above-mentioned positioning means 270.Below, the setting of rotary damper 281 is described.

The body shell 281a of rotary damper 281 is fixed on the damper support (not shown) that above-mentioned matrix 271 had.Under the state that the fulcrum 271a with above-mentioned rotary component 275 is provided with core, the rotor operation body of rotary damper 281 is connected on the above-mentioned rotary component 275, and described rotary component 275 is as the solid of rotation of force application mechanism 274.Thus, rotary damper 281 applies the swing resistance by rotary component 275 and linkage rod 276 to gear shift pedal 224.

Even substitute the manipulation cylinder 226 in the foregoing description, and adopt the structure of coming variable speed operation stepless speed changes devices 210, also can finish purpose of the present invention by motor and the combined manipulation driving mechanism that constitutes of thread mechanism.Therefore, these are handled cylinder 226 and operate driving mechanism and are referred to as shifting actuator 226.

Other mode of executions

1, as operating vehicle, can be riding formula rice transplanter or riding formula mowing machine, also can be wheeled charging crane etc.

2,, also can be belt-type device etc. as stepless speed changes devices 10.

3, the dependency relation data can comprise and the corresponding a plurality of dependency relation formulas of various conditions, perhaps also can be with the dependency relation formula in the corresponding coefficient of various conditions.

4, also alternative step change device 11, and adopt planetary speed variator.

5, also can adopt electronic cylinder, electric motor or hydraulic motor etc. as operating device 55.

6, also can adopt speed change lever etc. as variable speed operation spare 24.

Claims (13)

1. the load control structure of an operating vehicle comprises:

Be used to detect the operating position feeler mechanism of operating position of the variable speed operation spare of manual operation;

The load detecting mechanism of detection of engine load;

The swash plate positions feeler mechanism of the operating position of the swash plate of the variable displacement pump that detection is had in static oil pressure endless gearing device;

The pump operating device of the swash plate of the above-mentioned variable displacement pump of stepless operation;

The motor operating device of the swash plate handover operation of the variable capacity motor that will in above-mentioned static oil pressure endless gearing device, be had at least two shift position that comprise high speed position and low-speed position;

The control said pump is used the control mechanism of the action of operating device with operating device and said motor;

It is characterized in that above-mentioned control mechanism comprises:

Automatic pump swash plate control mechanism, it is according to the action with operating device of the detection control said pump of the detection of above-mentioned load detecting mechanism and above-mentioned swash plate positions feeler mechanism, so that engine loading is big more, the swash plate deceleration-operation degree of above-mentioned variable displacement pump is big more;

The control said motor is with the motor swashplate control mechanism of the action of operating device, so that the swash plate of above-mentioned variable capacity motor switches on above-mentioned two shift position at least;

In above-mentioned control mechanism, also comprise automatic motor swash plate control mechanism, this automatic motor swash plate control mechanism is according to the action with operating device of the detection control said motor of above-mentioned load detecting mechanism, when engine loading rises to the first predetermined setting value, the swash plate of above-mentioned variable capacity motor is switched to above-mentioned low-speed position from above-mentioned high speed position; When engine loading drops to the second predetermined setting value, the swash plate of above-mentioned variable capacity motor is switched to above-mentioned high speed position from above-mentioned low-speed position.

2. load control structure as claimed in claim 1 is characterized in that,

In above-mentioned control mechanism, comprise control mode switched the mode switching instruction mechanism of instructing,

Above-mentioned control mechanism is according to the instruction of above-mentioned mode switching instruction mechanism, the manual control mode that above-mentioned automatic pump swash plate control mechanism and above-mentioned automatic motor swash plate control mechanism all are failure to actuate, make above-mentioned automatic pump swash plate control mechanism action the semiautomatic control pattern, above-mentioned automatic pump swash plate control mechanism and above-mentioned automatic motor swash plate control mechanism are all moved automatic control mode between switch.

3. load control structure as claimed in claim 2 is characterized in that,

Under above-mentioned automatic control mode, above-mentioned automatic pump swash plate control mechanism is more blunt than the control feel of above-mentioned half control molding formula with respect to the control feel of engine loading.

4. load control structure as claimed in claim 2 is characterized in that,

Under above-mentioned automatic control mode, swash plate at above-mentioned variable capacity motor switches to from above-mentioned high speed position under the situation of above-mentioned low-speed position by the action of said motor swash plate control mechanism, and above-mentioned control mechanism switches to above-mentioned semiautomatic control pattern with control mode from above-mentioned automatic control mode.

5. load control structure as claimed in claim 1 is characterized in that,

Above-mentioned control mechanism is being controlled the action that said pump is used operating device with the action and the said motor of operating device, so that switch under the situation of above-mentioned low-speed position from above-mentioned high speed position at the swash plate of above-mentioned variable capacity motor, before the swash plate handover operation of above-mentioned variable capacity motor, make the swash plate deceleration-operation of above-mentioned variable displacement pump, after this side by side make the swash plate speedup operation of above-mentioned variable displacement pump with the swash plate handover operation of above-mentioned variable capacity motor.

6. load control structure as claimed in claim 1 is characterized in that,

Above-mentioned control mechanism is being controlled the action that said pump is used operating device with the action and the said motor of operating device, so that switch under the situation of above-mentioned high speed position from above-mentioned low-speed position at the swash plate of above-mentioned variable capacity motor, side by side make the swash plate deceleration-operation of above-mentioned variable displacement pump with the swash plate handover operation of above-mentioned variable capacity motor, after the swash plate handover operation of above-mentioned variable capacity motor, the swash plate speedup of above-mentioned variable displacement pump is operated on the swash plate handover operation operating position before that carries out above-mentioned variable capacity motor.

7. load control structure as claimed in claim 1 is characterized in that,

Also comprise and being used for be connected linking mechanism on the acceleration mechanism of above-mentioned motor of above-mentioned variable speed operation spare, detection is by the setting engine rotation speed sensor of the setting engine speed of above-mentioned acceleration mechanism setting, and the practical engine speeds sensor that detects above-mentioned actual engine speed;

Above-mentioned control mechanism judges between the practical engine speeds of setting engine speed that above-mentioned setting engine rotation speed sensor detects and above-mentioned practical engine speeds sensor whether have difference, and the operating position that detects according to this judged result and aforesaid operations position detecting mechanism carries out variable speed operation to above-mentioned stepless speed changes devices.

8. load control structure as claimed in claim 7 is characterized in that,

Above-mentioned control mechanism is judging do not have or roughly do not have under the situation of difference between above-mentioned detection setting engine speed and the above-mentioned detection practical engine speeds, set common control target speed according to the detection information of aforesaid operations position detecting mechanism, and stepless speed changes devices carried out variable speed operation, stepless speed changes devices is in and usually on the operating position of control target speed correspondence;

Between above-mentioned detection setting engine speed of judgement and above-mentioned detection practical engine speeds, exist under the situation of difference, according to the detection information setting of aforesaid operations position detecting mechanism than the common control target speed Correction and Control target velocity of low speed more, and stepless speed changes devices carried out variable speed operation, stepless speed changes devices is on the operating position with Correction and Control target velocity correspondence.

9. load control structure as claimed in claim 1 is characterized in that,

Above-mentioned control mechanism is in the detection according to above-mentioned load detecting mechanism, detecting above-mentioned engine loading is reduced under the following state of the second predetermined setting value, detection based on the aforesaid operations position detecting mechanism, detect under the situation of above-mentioned variable speed operation spare deceleration-operation, the control said motor does not make the swash plate of above-mentioned variable capacity motor switch on the above-mentioned high speed position from above-mentioned low-speed position with the action of operating device.

10. load control structure as claimed in claim 1 is characterized in that,

Above-mentioned control mechanism is according to the action with operating device of the detection control said pump of the detection of above-mentioned load detecting mechanism and above-mentioned swash plate positions feeler mechanism, so that engine loading is big more, the swash plate deceleration-operation degree of above-mentioned variable displacement pump is big more; And,

According to the action of the detection control said motor of above-mentioned load detecting mechanism with operating device, rise at engine loading under the situation of the first predetermined setting value, the swash plate of above-mentioned variable capacity motor is switched to above-mentioned low-speed position from above-mentioned high speed position; Under engine loading drops to situation below the second predetermined setting value, the swash plate of above-mentioned variable capacity motor is switched to above-mentioned high speed position from above-mentioned low-speed position.

11. load control structure as claimed in claim 10 is characterized in that,

Above-mentioned control mechanism is according to the detection of aforesaid operations position detecting mechanism, above-mentioned first setting value is become predetermined value corresponding to the operating position of above-mentioned variable speed operation spare, so that the operating position of above-mentioned variable speed operation spare is in low speed side more, the swash plate of above-mentioned variable capacity motor is switched to low-speed position from high speed position with more little engine loading.

12. load control structure as claimed in claim 1 is characterized in that,

Above-mentioned variable speed operation spare is a pedal.

13. load control structure as claimed in claim 1 is characterized in that,

Also comprise instruct and different with the above-mentioned variable speed operation spare manually operated type command devices of swash plate handover operation that are used for above-mentioned variable capacity motor in the above-mentioned control mechanism.

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