CN114810875A - Multi-mode air brake system and crane - Google Patents
Multi-mode air brake system and crane Download PDFInfo
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- CN114810875A CN114810875A CN202210567619.5A CN202210567619A CN114810875A CN 114810875 A CN114810875 A CN 114810875A CN 202210567619 A CN202210567619 A CN 202210567619A CN 114810875 A CN114810875 A CN 114810875A
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- 238000000034 method Methods 0.000 claims abstract description 14
- 238000003860 storage Methods 0.000 claims abstract description 13
- 230000001105 regulatory effect Effects 0.000 claims description 30
- 239000000725 suspension Substances 0.000 abstract description 10
- 238000005516 engineering process Methods 0.000 abstract description 2
- 239000003921 oil Substances 0.000 description 6
- 239000010426 asphalt Substances 0.000 description 4
- 239000004568 cement Substances 0.000 description 4
- 230000001276 controlling effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000004146 energy storage Methods 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000012938 design process Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000010720 hydraulic oil Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000010534 mechanism of action Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D65/00—Parts or details
- F16D65/14—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T11/00—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant
- B60T11/10—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant transmitting by fluid means, e.g. hydraulic
- B60T11/16—Master control, e.g. master cylinders
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T11/00—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant
- B60T11/10—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant transmitting by fluid means, e.g. hydraulic
- B60T11/28—Valves specially adapted therefor
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
- B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
- B60T13/24—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being gaseous
- B60T13/26—Compressed-air systems
- B60T13/36—Compressed-air systems direct, i.e. brakes applied directly by compressed air
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T17/00—Component parts, details, or accessories of power brake systems not covered by groups B60T8/00, B60T13/00 or B60T15/00, or presenting other characteristic features
- B60T17/002—Air treatment devices
- B60T17/004—Draining and drying devices
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T17/00—Component parts, details, or accessories of power brake systems not covered by groups B60T8/00, B60T13/00 or B60T15/00, or presenting other characteristic features
- B60T17/04—Arrangements of piping, valves in the piping, e.g. cut-off valves, couplings or air hoses
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C13/00—Other constructional features or details
- B66C13/18—Control systems or devices
- B66C13/20—Control systems or devices for non-electric drives
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D1/00—Pipe-line systems
- F17D1/02—Pipe-line systems for gases or vapours
- F17D1/04—Pipe-line systems for gases or vapours for distribution of gas
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D3/00—Arrangements for supervising or controlling working operations
- F17D3/01—Arrangements for supervising or controlling working operations for controlling, signalling, or supervising the conveyance of a product
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2121/00—Type of actuator operation force
- F16D2121/02—Fluid pressure
- F16D2121/08—Fluid pressure acting on a membrane-type actuator, e.g. for gas pressure
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2125/00—Components of actuators
- F16D2125/02—Fluid-pressure mechanisms
- F16D2125/16—Devices for bleeding or filling
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Transportation (AREA)
- General Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Hydraulic Control Valves For Brake Systems (AREA)
Abstract
The invention belongs to the engineering machinery technology, and particularly relates to a multi-mode air pressure braking system and a crane, which comprise braking loops respectively connected through a plurality of air cylinders, wherein each braking loop is connected with a plurality of braking units in parallel and is connected with a braking master cylinder in series; the brake unit comprises a relay valve and a brake air chamber, a control port of the relay valve is connected with an air outlet of the brake master cylinder, and an air inlet of the relay valve is connected with an air storage cylinder on each brake loop; an air inlet of the brake master cylinder is connected with an air storage cylinder on the brake loop; the method comprises the following steps that an air chamber quantity control unit is installed on a brake unit and/or a pressure adjusting unit is installed on a brake circuit; the input end of the controller is connected with the pressure sensor, and the output end of the controller is connected with the electromagnetic valve and the electromagnetic proportional valve. The invention has a plurality of braking modes, and is suitable for different driving conditions; the braking mode can be manually adjusted according to different driving states; or automatically switching various braking modes according to information such as suspension pressure and the like; meanwhile, the emergency operation device has a mechanical emergency operation function.
Description
Technical Field
The invention belongs to the engineering machinery technology, and particularly relates to a multi-mode air brake system and a crane.
Background
The all-terrain crane has various driving states, such as a boarding state (the vehicle weight is less than or equal to 55t), an axle load 12t state and a heavy load transition state; further, the heavy-load transition state has a plurality of types, such as a driving state with a full main arm and a full landing leg, a driving state with a full main arm and a landing leg and a counterweight, a driving state with a full main arm and a landing leg and a super-lift, a driving state with a full main arm and a landing leg and a wind power arm, and the like. Under different driving states, the load of each bridge, the height of the mass center of the whole machine and the total weight are different, and the requirements on the braking capacity are different. Meanwhile, the operation field of the all-terrain crane is complex, asphalt cement road surfaces with good road conditions and muddy road surfaces with poor road conditions exist, and the requirements for braking are different under different road conditions in the same vehicle state.
The braking performance is an important index of the driving safety, and the quality of the braking system is related to the braking efficiency and the braking direction stability of the vehicle, and meanwhile, the manufacturing cost and the use cost of the vehicle are affected. When the braking capability is not matched with the vehicle state or road condition, the problems of abnormal locking of braking wheels, large braking distance and the like can be caused, and the driving safety is influenced; meanwhile, the problems of high frequency of replacing the dryer with large air consumption of the vehicle, serious tire abrasion and the like can be brought, and the vehicle cost of a customer is increased.
At present, the all-terrain crane in the industry adopts a conventional air braking system with unadjustable braking capability, and the number of braking air chambers, the maximum braking air pressure and the like of the air braking system are unadjustable; the braking system only has one mode, only can ensure a set driving state, and cannot give consideration to various driving states.
Although the service braking can be realized by the service braking scheme, the braking force is fixed (the braking force is fixed under the condition that the braking angle on the brake master cylinder is certain), and the service braking scheme cannot adapt to various working conditions. The following disadvantages exist in particular:
1) for light load conditions: the method has the advantages that firstly, the braking force is redundant, and risks such as tire locking, uncontrollable direction and the like are easy to occur; ②
Large air consumption, large loss to air compressor, drier and the like, and high use and maintenance cost.
2) For heavy load conditions: the braking force is insufficient, the braking distance is long, and braking safety accidents are easy to happen.
At present, a load-sensing proportional brake system mainly adopts a load-sensing proportional valve or a device with similar functions, and the pressure of the brake system can be adjusted according to the deformation of a vehicle body, so that the brake capacity of the vehicle can be adjusted. The load-sensing proportional valve is generally mounted at two ends to two relatively deformable components, for example, one end is fixed to a vehicle frame, the other end is fixed to a vehicle axle, the vehicle loads are different, and the deformation amount of a suspension (such as a leaf spring and the like) of the load-sensing proportional valve is different, so that the output pressure of the load-sensing proportional valve is controlled by the deformation amount. The chassis of the all-terrain crane adopts an oil-gas suspension system, the oil-gas suspension can not visually measure the change condition of the vehicle load, and meanwhile, the oil-gas suspension can actively or passively adjust the height of the frame according to the intention of a driver or the requirement of working conditions so as to obtain better driving trafficability. The conventional load-sensing proportional brake system cannot be directly applied to a vehicle equipped with the above-described suspension.
Disclosure of Invention
In order to overcome the technical problems, the invention provides a multi-mode air braking system and a crane.
In order to achieve the purpose, the invention adopts the following technical scheme:
a multi-mode air braking system comprises an air compressor, a dryer and a multi-loop valve which are connected in sequence, wherein the multi-loop valve is respectively connected with a first braking loop and a second braking loop through a first braking loop air cylinder and a second braking loop air cylinder; the brake unit comprises a relay valve and a plurality of brake chambers, and the plurality of brake chambers are connected in series and connected into a group and connected with an air outlet of the relay valve; the control port of the relay valve is connected with the air outlet of the brake master cylinder, and the air inlet of the relay valve is connected with the air storage cylinder on the brake loop; an air inlet of the brake master cylinder is connected with an air storage cylinder on the brake loop; the pneumatic brake system is characterized in that at least one brake unit is provided with an air chamber quantity control unit and/or at least one brake circuit is provided with a pressure regulating unit; the air chamber quantity control unit is composed of an electromagnetic valve, and the pressure adjusting unit is composed of an electromagnetic proportional valve; the pneumatic braking system further comprises a controller and a pressure sensor, wherein the input end of the controller is connected with the pressure sensor, the output end of the controller is connected with the electromagnetic valve and the electromagnetic proportional valve, and the pressure sensor is installed on a supporting oil cylinder between the axle and the frame.
Further, the air chamber quantity control unit is composed of an electromagnetic valve and a mechanical valve which are connected in parallel, and the pressure adjusting unit is composed of an electromagnetic proportional valve and a mechanical pressure adjusting valve which are connected in parallel.
Furthermore, the air chamber number control unit is arranged at a control port of the relay valve, or an air inlet of the relay valve, or an air outlet of the relay valve, or an air inlet of the brake air chamber; the pressure regulating unit is arranged at an air inlet of the master cylinder, or an air outlet of the master cylinder, or an air inlet of the relay valve, or an air inlet of the brake air chamber, or an air inlet of each brake loop air cylinder.
Further, the crane adopts a multi-mode air braking system.
Further, a control method of the multi-mode air brake system is an electric control execution mode, and specifically comprises the following steps:
the bridge load data is collected through a pressure sensor arranged on a support oil cylinder between an axle and a frame, and is analyzed by a controller, and a control signal is output according to the size of the bridge load data to control an electromagnetic valve or/and an electromagnetic proportional valve to work, so that the number of brake air chambers or/and the brake pressure are automatically adjusted;
the control principle of the number of the brake chambers is as follows: the controller outputs control signals to control the on-off of the electromagnetic valve on the brake unit, so as to control the on-off of the relay valve and control the working quantity of the brake chambers.
Control principle of brake pressure regulation: the controller outputs a control signal to control the work of the electromagnetic proportional valve on the brake circuit, and then the brake pressure on the brake circuit is controlled.
Furthermore, the control method can also set road condition information, and the controller controls the electromagnetic valve or/and the electromagnetic proportional valve to work according to the pressure sensor information and the input road condition information, and automatically controls the number of the brake air chambers or/and the brake pressure.
Furthermore, the electric control execution mode is provided with a plurality of fixed modes according to common working conditions of the air brake system, and manual adjustment is carried out through a control knob arranged in the cab; the control knob has a higher priority than automatic control.
Furthermore, the control method also comprises a manual control execution mode, wherein the number of the brake air chambers or/and the brake pressure is adjusted by manually controlling the mechanical valve or/and the mechanical pressure regulating valve by arranging the mechanical valve connected with the electromagnetic valve in parallel and the mechanical pressure regulating valve connected with the electromagnetic proportional valve in parallel.
The invention provides a multi-mode air brake system and a crane using the same. The air pressure braking system has multiple braking modes and is suitable for different running conditions; the braking mode can be manually adjusted according to different driving states; or automatically switching various braking modes according to information such as suspension pressure and the like; meanwhile, the emergency operation device has a mechanical emergency operation function.
The service braking scheme shown above controls the braking capacity of the vehicle by controlling the maximum braking pressure and the number of active brake chambers. The following beneficial effects can be brought in:
1) the braking capacity can be adjusted according to different vehicle states, and the optimal braking efficiency is ensured to be exerted: under the condition of light load, the maximum pressure of the system can be reduced, and the number of brake air chambers is reduced; under the condition of heavy load, the maximum pressure of the system can be improved, and the number of brake chambers is increased; under the request of light front and heavy back or light front and heavy back, the number of the air chambers of the part or the maximum pressure of the system can be independently adjusted.
2) The braking capacity can be adjusted according to different road surface states, and the optimal braking efficiency is ensured to be exerted: under the condition of good road conditions, such as dry asphalt pavement or cement pavement, the braking capacity of the vehicle can be improved by improving the maximum pressure of the system or increasing the number of brake air chambers; under the condition of poor road conditions, such as wet and slippery road surfaces or soft mud road surfaces, the maximum pressure of the system or the number of brake air chambers can be reduced, so that the braking capacity is reduced, the locking of the vehicle is reduced, and the braking and slipping of the vehicle are reduced.
3) Under the condition of light load of the vehicle or poor road conditions, the braking capacity is properly reduced, the risk of locking the vehicle can be reduced, and the tire locking wear is reduced; the air consumption of the brake system is reduced, the service life of the brake system is prolonged, the maintenance frequency is reduced, for example, the service life of an air compressor is prolonged, and the replacement frequency of a dryer is reduced.
4) Under the condition of a heavy load state or good road conditions of the vehicle, the braking capacity is properly improved, the braking efficiency can be improved, the braking distance is reduced, and the driving safety is improved.
Drawings
FIG. 1: the control scheme of the existing service brake system is shown schematically;
FIG. 2: the structure schematic diagram of the air braking system of the eight-bridge crane in the prior art;
FIG. 3: the invention discloses a schematic diagram of a control scheme of a braking system;
FIG. 4: the invention discloses a structural schematic diagram of a pneumatic braking system on an eight-axle all-terrain crane vehicle;
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Abbreviations and Key term definitions
The automobile crane comprises: a crane (a crane capable of performing multiple actions such as vertical lifting, horizontal conveying and the like within a certain range) arranged on a common automobile chassis or a special chassis can move rapidly and has good maneuverability.
A braking system: a set of special systems capable of producing a certain degree of positive braking effect when the outside exerts a force or torque on a certain part of the vehicle.
The air braking system comprises: the brake pedal controls the compressed air to enter the wheel brake to form braking by taking the compressed air as a braking source.
Braking efficiency: the evaluation index of the braking system generally includes two indexes of a braking distance and a braking deceleration.
The running condition is as follows: the vehicle is subjected to different working environments during running, such as load, vehicle speed, road adhesion and the like.
A suspension system: the general name of all force transfer devices between a vehicle frame (or a bearing type vehicle body) and an axle (or a wheel). The stress of the road surface acting on the wheels is transferred to the frame (or the bearing type vehicle body). According to different elastic elements, the elastic elements are divided into a leaf spring type, an air spring type, an oil-gas suspension type and the like.
Load sensing proportional valve: the oil pressure or air pressure regulating device comprises a metal guide rod, wherein the guide rod is connected to a frame, and the pressure of an output port can be changed along with the displacement of the guide rod.
A master cylinder: the operating mechanism of the service brake system is generally disposed in the cab. The pedal displacement signal is converted into an air pressure signal, and then the execution and the release of the brake are controlled.
A relay valve: a part of the pneumatic brake system may serve to shorten the reaction time. The air inlet of the air storage cylinder is connected with the air storage cylinder (including indirect connection), the air outlet of the air storage cylinder is connected with the brake air chamber (including indirect connection), and the control port of the air storage cylinder is connected with the brake master cylinder (including indirect connection). The air pressure of the air outlet is positively changed along with the air pressure of the control port; when the control port is empty, the air outlet is disconnected with the air inlet; when the air pressure of the control port rises, the valve between the air outlet and the air inlet is gradually opened.
A brake chamber: the pressure of the compressed air is converted into mechanical force to push the brake to act, and the vehicle brake is realized. The mechanical force is proportional to the input air pressure. Also called as brake cylinder.
A controller: the control center is responsible for receiving signals (such as pressure sensor signals and control knob signals) on one hand and issuing braking instructions to the electromagnetic valve and the electromagnetic proportional valve on the other hand.
As shown in fig. 1, the conventional air brake system with nonadjustable braking capability is adopted in the conventional service brake system control scheme of all-terrain cranes in the industry, and the number of brake chambers, the maximum brake air pressure and the like are nonadjustable; the braking system only has one mode, only can ensure a set driving state, and cannot give consideration to various driving states.
As shown in fig. 2, an eight-bridge all-terrain crane is taken as an example to describe the prior art. The arrangement scheme of the service brake system of the eight-axle all-terrain crane comprises a brake master cylinder 10, an air compressor 11, a dryer 12, a multi-circuit valve 13, a first brake circuit air cylinder 14, a second brake circuit air cylinder 15, a spring energy storage brake air chamber 21, a diaphragm brake air chamber 22, a relay valve 31, a relay valve 36 and other air elements. The action mechanism is as follows:
a driver steps on a brake pedal by feet to control the pressure of an air outlet of the brake master cylinder 10, so that an air inlet and an air outlet of a relay valve (comprising a relay valve 31 to a relay valve 36) are controlled to be communicated, the air pressure of the air outlet enters a brake air chamber (comprising a spring energy storage brake air chamber 21 and a diaphragm brake air chamber 22), and the brake air chamber pushes a brake (connected with an axle and not shown in the figure) to act, so that the service brake of the whole vehicle is realized.
When the driver does not step on the brake pedal, the air pressure in the air outlet of the brake master cylinder 10, the air outlet of the relay valve and the brake air chamber is zero; at this time, the brake system is not operated, i.e., no braking. When a driver steps on a brake pedal, the air pressure value of an air outlet (connected with control ports of the relay valves) of the brake master cylinder 10 is increased, the air outlet of each relay valve is opened, air is supplied to the brake air chambers 2 of the bridges, and vehicle braking is achieved.
In the existing service braking system, under the condition that the system pressure is constant and the stepping angle of a brake pedal is constant, the gas pressure in each brake chamber 2 is constant and nonadjustable; and after the brake pedal is stepped on, the relay valve is opened, so that all the brake air chambers are ensured to be ventilated, and the number of the acting brake air chambers is constant. Therefore, the braking capability and distribution of the braking system are not adjustable, and the braking system cannot be well suitable for different driving conditions.
The invention provides a multi-mode air brake system and a crane, wherein the air brake system has multiple brake modes and is suitable for different running conditions; the braking mode can be manually adjusted according to different driving states; or automatically switching various braking modes according to information such as suspension pressure and the like; meanwhile, the emergency operation device has a mechanical emergency operation function.
As shown in fig. 3 and 4, the multi-mode pneumatic brake system of the present invention mainly includes conventional brake system components such as a controller 1, a brake chamber 2 (including a spring energy storage brake chamber 21 and a diaphragm brake chamber 22), a relay valve 3, an electromagnetic valve 5 (including an electromagnetic valve i 51 and an electromagnetic valve ii 52), an electromagnetic proportional valve 7 (including a first brake circuit electromagnetic proportional valve 71 and a second brake circuit electromagnetic proportional valve 72), a pressure sensor 9, a master brake pump 10, an air compressor 11, a dryer 12, a multi-circuit valve 13, and air cylinders (including a first brake circuit air cylinder 14 and a second brake circuit air cylinder 15), as well as pipelines and wires. The air compressor 11, the dryer 12 and the multi-circuit valve 13 are sequentially connected, the multi-circuit valve 13 is respectively connected with the first brake circuit and the second brake circuit through the first brake circuit air cylinder 14 and the second brake circuit air cylinder 15, and a plurality of brake units are connected in parallel on the brake circuits and are connected with the brake master cylinder 10 in series; an air inlet of the brake master cylinder 10 is connected with an air storage cylinder on the brake loop; the brake unit comprises a relay valve 3 and a plurality of brake chambers 2, and the brake chambers 2 are connected in parallel to form a group and are connected with an air outlet of the relay valve 3; the input end of the controller 1 is connected with a pressure sensor 9, the output end of the controller 1 is connected with an electromagnetic valve 5 and an electromagnetic proportional valve 7, and the pressure sensor 9 is installed on a supporting oil cylinder between an axle and a frame.
The pressure sensor 9 calculates the sprung mass, the sprung mass + the unsprung mass, and the total load of the tire at the axle, that is, the axle load, by detecting the pressure of the hydraulic oil. The left side and the right side of one axle are respectively provided with a pressure sensor; the whole trolley is provided with at least one pressure sensor on the left and right sides of one front axle and one pressure sensor on the left and right sides of one rear axle. Other axles may also be equipped with pressure sensors, the more the sensors are placed on the axles, the more accurate the axle load calculation is. Through the design of a hydraulic system, the pressure of a plurality of supporting oil cylinders at the front left, the front right, the back left and the back right can be ensured to be equal or approximately equal.
In the air pressure braking system, the number of working brake air chambers and the maximum brake pressure limit value can be adjusted, the two can be combined to realize a plurality of braking modes, so that different vehicle running states can be met, the electromagnetic valve 5 is an air chamber number control unit and is arranged on the braking unit to control the number of the brake air chambers, and the electromagnetic proportional valve 7 is a pressure adjusting unit and is arranged on a braking loop to control the braking pressure.
The invention selects various braking modes of the pneumatic braking system, bridge load data monitored by a pressure sensor 9 arranged on a support oil cylinder between a bridge and a frame is analyzed by a controller 1, and a control signal is output according to the size of the bridge load data to control an electromagnetic valve 5 or/and an electromagnetic proportional valve 7 to work, so that the adjustment of the number of braking air chambers 2 and/or the braking pressure is completed, and the automatic adjustment of the modes is realized. For example, when the running road surface is a cement asphalt road surface, the axle load is 12t, the braking pressure is adjusted to be 8bar, and the number of the braking air chambers is 16; in a 16t axle load driving state, the braking air pressure is adjusted to be 10bar, and the number of the braking air chambers is 16; and in the running state of the axle load of 21t, the braking air pressure is adjusted to be 10bar, and the number of the braking air chambers is 20. Meanwhile, according to the common working conditions of the air brake system, a plurality of fixed modes are set, for example: the mode 1 is set to have the brake air pressure of 8bar and the number of the brake air chambers of 16; the mode 2 is set to have the brake air pressure of 10bar and the number of the brake air chambers of 16; the mode 3 is set to have 10bar of brake air pressure and 20 brake air chambers. Manual adjustment is performed by means of a control knob 4 arranged inside the cab; the control knob 4 has a higher priority of control than automatic control. The above control modes are all executed by electric elements (such as the electromagnetic valve 5, the electromagnetic proportional valve 7 and the like), and are called electric control execution modes.
Furthermore, in order to improve the accuracy of the braking system for controlling the working condition, the road condition information can be manually set on the basis that the pressure sensor 9 collects the bridge load data, and the controller 1 controls the electromagnetic valve 5 or/and the electromagnetic proportional valve 7 to work according to the information of the pressure sensor and the input road condition information, so that the number of the braking air chambers and/or the braking pressure can be automatically adjusted. For example, when the axle load is monitored to 21t, when the cement road surface or the asphalt road surface is monitored, the braking air pressure is adjusted to 10bar, and the number of the braking air chambers is 20; the axle load is monitored to 21t, the road surface is muddy, the air pressure is adjusted to 9bar, and the number of the brake air chambers is 16.
Furthermore, in order to improve the safety of the braking system, a mechanical valve 6 (comprising a mechanical valve) is additionally arranged
I61, a mechanical valve II 62 and a mechanical pressure regulating valve 8 (comprising a first brake circuit mechanical pressure regulating valve 81 and a second brake circuit mechanical pressure regulating valve 82), wherein the mechanical valve 6 is connected with the electromagnetic valve 5 in parallel to form a gas chamber number control unit, and the mechanical pressure regulating valve 8 is connected with the electromagnetic proportional valve 7 in parallel to form a pressure regulating unit. When the electric control execution mode fails, the setting of the braking mode is realized through the manual control execution mode, and the method is safe and reliable.
The control principle of the number of working brake chambers is as follows: and an electromagnetic valve 5 and/or a mechanical valve 6 are/is added at a control port of the relay valve 3 to control the on-off of the relay valve 3, so that the number of the brake air chambers 2 is controlled. The electromagnetic valve 5 and the mechanical valve 6 are connected in parallel and are connected to a control port of the relay valve 3 as a whole, wherein the electromagnetic valve 5 can realize electric control, and the mechanical valve 6 can realize emergency manual control. Further, the electromagnetic valve 5 and the mechanical valve 6 may be disposed at an inlet of the relay valve 3, at an outlet of the relay valve 3, or at an inlet of the brake chamber 2.
Control principle of brake pressure regulation: an electromagnetic proportional valve 7 and/or a mechanical pressure regulating valve 8 are/is added at an air inlet of a master cylinder 10 to control the pressure of the air inlet of the master cylinder 10, so that the working pressure of the whole system is controlled. The electromagnetic proportional valve 7 and the mechanical pressure regulating valve 8 are connected in parallel and are connected to an air inlet of a master cylinder 10 as a whole. The electromagnetic proportional valve 7 can realize electric control, and the mechanical pressure regulating valve 8 can realize emergency manual control. Further, the electromagnetic proportional valve 7 and the mechanical pressure regulating valve 8 can also be arranged at the air outlet of the master cylinder 10 to control the pressure at the air outlet of the master cylinder 10, can also be arranged at the air inlet of the relay valve 3 to control the pressure at the air inlet of the relay valve 3, can also be arranged at the air inlet of the brake air chamber 2 to control the pressure of the brake air chamber 2, and can also be arranged at the air inlet of the air storage cylinder to control the pressure of the air storage cylinder.
As shown in fig. 4, the embodiment takes an eight-bridge all-terrain crane as an example to describe the technical solution of the present invention.
The mechanism of action of the pneumatic brake system of the present invention is as follows: a driver steps on a brake pedal to control the pressure of the air outlet of the brake master cylinder 10, so that the air inlet and the air outlet of the relay valve 3 are controlled to be communicated, the air pressure of the air outlet of the relay valve 3 enters the brake air chamber 2, and the brake air chamber 2 pushes a brake (connected with an axle and not shown in the figure) to act, so that the service brake of the whole vehicle is realized.
Meanwhile, the air pressure brake system of the present invention adjusts the intake pressure of the master cylinder 10 through the electromagnetic proportional valve 71 or the mechanical pressure regulating valve 81, thereby controlling the pressure of the first brake circuit; similarly, the pressure of the second brake circuit is controlled by the electromagnetic proportional valve 72 or the mechanical pressure regulating valve 82. By means of this control logic, the maximum working pressure of the pneumatic brake system of the invention can be controlled.
The pneumatic braking system controls the on-off of the pipeline of the relay valve 3 through the electromagnetic valve 5 or the mechanical valve 6. When at least one of the electromagnetic valve I51 and the mechanical valve I61 of the air chamber quantity control unit I is communicated, the master brake pump 10 can control the relay valve 3 of the brake unit where the air chamber quantity control unit I is located to act, so that the diaphragm brake air chamber 22 connected with the relay valve 3 works; when both are disconnected, the master cylinder 10 no longer controls the operation of the relay valve 3, and the diaphragm brake chamber 22 connected to the relay valve 3 stops operating. Similarly, the electromagnetic valve II 52 and the mechanical valve II 62 of the air chamber number control unit II have the same functions and control the working state of the diaphragm brake air chamber 22 connected with the relay valve 3 of the brake unit in which the air chamber number control unit II is located. By means of this control logic, the number of active brake chambers 2 can be controlled.
In the specific design process of the pneumatic brake system of the present invention, the following adjustments may be made:
1. the number of the air chamber number control units shown in fig. 4 may be 2, or may be 1 or other numbers, and is specifically set according to actual requirements.
Note: the electromagnetic valve 51I and the mechanical valve I61 are an air chamber number control unit I, and the electromagnetic valve II 52 and the mechanical valve II 62 are an air chamber number control unit II.
2. The number of the pressure regulating units shown in fig. 4 may be 2, or may be 1 or other numbers, and is specifically set according to actual requirements.
Note: the first brake circuit electromagnetic proportional valve 71 and the first brake circuit mechanical pressure regulating valve 81 are a pressure regulating unit i, and the second brake circuit electromagnetic proportional valve 72 and the second brake circuit mechanical pressure regulating valve 82 are another pressure regulating unit ii.
3. The air chamber number control unit can be arranged at a control port of the relay valve 3 (as shown in fig. 4), an air inlet of the relay valve 3, an air outlet of the relay valve 3, an air inlet of the brake air chamber 2, and other positions, and is specifically set according to actual requirements.
4. The pressure regulating unit can be arranged at an air inlet of the master cylinder 10 (as shown in fig. 4), an air outlet of the master cylinder 10, an air inlet of an air reservoir and an air inlet of the relay valve 3; may also be arranged at the air inlet of the brake chamber 2; the device can be flexibly arranged at other positions, and is particularly set according to actual requirements.
5. The air chamber quantity control unit can be in a form shown in fig. 4, and can also adopt a form that two electromagnetic valves 5 are connected in parallel or two mechanical valves 6 are connected in parallel; further, the electromagnetic valve 5 can be replaced by other electrically-controlled on-off valves, and the mechanical valve 6 can be replaced by other manually-controlled on-off valves.
6. The pressure regulating unit can be in the form shown in fig. 4, and can also adopt the form that two electromagnetic proportional valves 7 are connected in parallel or two mechanical pressure regulating valves 8 are connected in parallel; furthermore, the electromagnetic proportional valve 7 can be replaced by other electric pressure regulating devices, and the mechanical pressure regulating valve 8 can be replaced by other manual pressure regulating devices.
7. The pressure adjusting unit and the air chamber quantity control unit can be used independently or can be used in combination.
Claims (8)
1. A multi-mode air pressure braking system comprises an air compressor (11), a dryer (12) and a multi-loop valve (13) which are connected in sequence, wherein the multi-loop valve (13) is respectively connected with a first braking loop and a second braking loop through a first braking loop air cylinder (14) and a second braking loop air cylinder (15), each braking loop is connected with a plurality of braking units in parallel, and each braking loop is connected with a master braking pump (10) in series;
the brake unit comprises a relay valve (3) and a plurality of brake chambers (2), wherein the brake chambers (2) are connected in series and in parallel to form a group and are connected with an air outlet of the relay valve (3);
a control port of the relay valve (3) is connected with an air outlet of the brake master cylinder (10), and an air inlet of the relay valve (3) is connected with an air storage cylinder on the brake circuit;
an air inlet of the brake master cylinder (10) is connected with an air storage cylinder on the brake loop;
the method is characterized in that:
the pneumatic brake system is characterized in that at least one brake unit is provided with an air chamber quantity control unit and/or at least one brake circuit is provided with a pressure regulating unit;
the air chamber quantity control unit is composed of an electromagnetic valve (5), and the pressure adjusting unit is composed of an electromagnetic proportional valve (7);
the pneumatic braking system further comprises a controller (1) and a pressure sensor (9), the input end of the controller (1) is connected with the pressure sensor (9), the output end of the controller (1) is connected with the electromagnetic valve (5) and the electromagnetic proportional valve (7), and the pressure sensor (9) is installed on a supporting oil cylinder between an axle and a frame.
2. A multi-mode pneumatic brake system according to claim 1, wherein: the air chamber quantity control unit is composed of an electromagnetic valve (5) and a mechanical valve (6) which are connected in parallel, and the pressure adjusting unit is composed of an electromagnetic proportional valve (7) and a mechanical pressure adjusting valve (8) which are connected in parallel.
3. A multi-mode pneumatic brake system according to claim 1 or claim 2, wherein: the air chamber number control unit is arranged at a control port of the relay valve (3), or an air inlet of the relay valve (3), or an air outlet of the relay valve (3), or an air inlet of the brake air chamber (2); the pressure adjusting unit is arranged at an air inlet of the master cylinder (10), or an air outlet of the master cylinder (10), or an air inlet of the relay valve (3), or an air inlet of the brake air chamber (2), or an air inlet of each brake loop air cylinder.
4. An all-terrain crane, characterized in that: the crane employs a multi-mode pneumatic brake system as claimed in any one of claims 1 to 3.
5. A control method of a multi-mode pneumatic brake system according to claim 1, wherein the control method is an electronically controlled execution mode, and specifically comprises the following steps:
bridge load data acquired by a pressure sensor (9) arranged on a support oil cylinder between an axle and a frame are analyzed by a controller (1), and a control signal is output according to the size of the bridge load data to control an electromagnetic valve (5) or/and an electromagnetic proportional valve (7) to work so as to automatically control the number of brake air chambers and/or brake pressure;
the control principle of the number of the brake chambers is as follows: the controller (1) outputs a control signal to control the on-off of the electromagnetic valve (5) on the brake unit, so as to control the on-off of the relay valve (3) and control the working quantity of the brake air chambers (2);
control principle of brake pressure regulation: the controller (1) outputs a control signal to control an electromagnetic proportional valve (7) on the brake circuit to work, and then the brake pressure on the brake circuit is controlled.
6. The control method according to claim 5, characterized in that: the control method can also set road condition information, and the controller (1) controls the electromagnetic valve (5) or/and the electromagnetic proportional valve (7) to work according to the pressure sensor information and the input road condition information, and automatically controls the number of the brake air chambers and/or the brake pressure.
7. The control method according to claim 5 or 6, characterized in that: the electric control execution mode is provided with a plurality of fixed modes according to common working conditions of the air braking system, and manual adjustment is performed through a control knob (4) arranged in the cab; the control priority of the control knob (4) is higher than that of automatic control.
8. The control method according to claim 7, characterized in that: the control method further comprises a manual control execution mode, wherein the mechanical valve (6) connected with the electromagnetic valve (5) in parallel and the mechanical pressure regulating valve (8) connected with the electromagnetic proportional valve (7) in parallel are arranged, the mechanical valve (6) or/and the mechanical pressure regulating valve (8) are/is manually controlled, and the number of the brake air chambers and/or the brake pressure are/is adjusted.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202210567619.5A CN114810875A (en) | 2022-05-24 | 2022-05-24 | Multi-mode air brake system and crane |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210567619.5A CN114810875A (en) | 2022-05-24 | 2022-05-24 | Multi-mode air brake system and crane |
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| CN202210567619.5A Pending CN114810875A (en) | 2022-05-24 | 2022-05-24 | Multi-mode air brake system and crane |
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