CN110834116A

CN110834116A - Machine tool and design method

Info

Publication number: CN110834116A
Application number: CN201911137008.1A
Authority: CN
Inventors: 赵海荣
Original assignee: Individual
Current assignee: Taizhou Eastern Cnc Technology Co ltd
Priority date: 2019-11-20
Filing date: 2019-11-20
Publication date: 2020-02-25
Anticipated expiration: 2039-11-20
Also published as: CN110834116B

Abstract

The invention discloses a machine tool and a design method, belongs to the field of machining, and particularly relates to cutting of a circular tube. Comprises a bed seat and a cutting device; the bed seat comprises a chuck which clamps the round tube to rotate; the cutting device is arranged on the bed seat; the guide rail is fixedly connected with the bed base, the length direction of the guide rail is parallel to the circular tube, and the bracket moves along the guide rail; the bracket is sleeved at the far end of the circular tube; the cutter is connected with the bracket in a sliding way, the material pushing rod is connected with the bracket in a sliding way, the fixed length disc is fixedly connected with the bracket and is contacted with the far end of the circular tube; the driving disc component driven by the transmission component enables the support to move towards the chuck direction, when the fixed-length disc is contacted with the far end of the circular tube, the support cannot move continuously, the transmission component drives the driving disc component to operate, and the driving disc component drives the cutter to feed, so that the circular tube is cut; the driving disc component drives the material pushing rod to forcibly push out the intercepted circular tube. The machine tool provided by the invention has the advantages of small error, high efficiency, simple structure and low cost when used for cutting round pipes into specified lengths in batches.

Description

Machine tool and design method

Technical Field

The invention discloses a machine tool and a design method, belongs to the field of machining, and particularly relates to cutting of a circular tube.

Background

In the prior art, circular tubes are cut into a specified length in batches, a toothless saw or a toothed saw is used for blanking after the length is manually measured, the method has large error, the consistency of the length of each blanked circular tube cannot be ensured, the circular tubes are required to be manually clamped and then cut every time, and the working efficiency is also low; the prior art has another solution, a special blanking machine tool is used, the special blanking machine tool in the prior art adopts a double-clamp scheme, after a first clamp clamps a round tube to feed a required length, a second clamp clamps the round tube to start cutting (using a toothless saw or a toothed saw), and the first clamp is loosened and retreated to an initial position, so that in order to realize fixed-length cutting, a numerical control technology must be used, and in addition, the structure of the double clamp is complex and the cost is high.

In summary, the prior art has the following problems of large error, low efficiency, complex machine tool structure and high cost when the round tubes are cut into the specified length in batch.

Disclosure of Invention

The invention mainly aims to solve the problems of large error, low efficiency, complex machine tool structure and high cost of the circular tube cutting machine tool in the prior art.

In order to achieve the above purpose, the scheme is as follows:

designing a machine tool, which is characterized by comprising a bed seat and a cutting device; the bed seat comprises a chuck which clamps the round tube to rotate; the cutting device is arranged on the bed seat; the cutting device comprises a guide rail, a bracket, a cutter, a material pushing rod, a fixed-length disc, a transmission member and a disc driving member matched with the transmission member; the guide rail is fixedly connected with the bed base, the length direction of the guide rail is parallel to the circular tube, and the bracket moves along the guide rail; the bracket is sleeved at the far end of the circular tube; the cutter is connected with the bracket in a sliding way, the material pushing rod is connected with the bracket in a sliding way, the fixed length disc is fixedly connected with the bracket and is contacted with the far end of the circular tube; the driving disc component driven by the transmission component enables the support to move towards the chuck direction, when the fixed-length disc is contacted with the far end of the circular tube, the support cannot move continuously, the transmission component drives the driving disc component to operate, and the driving disc component drives the cutter to feed, so that the circular tube is cut; the driving disc component drives the material pushing rod to forcibly push out the intercepted circular tube.

Further, the machine tool is characterized in that the cutter is connected with the support in a sliding mode, the sliding connection direction is the radius direction of the circular tube, the first end of the cutter is connected with the extrusion disc in a rotating mode, the rotating axis is parallel to the axis of the circular tube, and the second end of the cutter is connected with the second end of the connecting rod in a swinging mode.

Furthermore, the machine tool is characterized in that a supporting wheel is further arranged at the position opposite to the extrusion disc, and the supporting wheel is connected with the support through a roller carrier.

Furthermore, the machine tool is characterized in that a crank disc is rotationally connected with the support, the crank disc is provided with a circular outer peripheral surface, and a first crank and a second crank are arranged on the end surface of the crank disc; the first crank is rotatably connected with the first end of the connecting rod.

Furthermore, the machine tool is characterized in that the material pushing rod is connected with the support in a sliding mode, and the first end of the material pushing rod is fixedly connected with the push plate; the second end of the pushing rod is provided with a sliding groove, and the sliding groove is connected with a second crank on the crank disc in a sliding mode.

Furthermore, the machine tool is characterized in that one surface of the push plate, which faces the chuck, is a plane, and the plane has intersection with the section projection of the circular tube in the whole pushing and resetting process of the push plate.

Furthermore, the machine tool is characterized in that the fixed length disc is rotatably connected with the support, the axis of the rotary connection is overlapped with the rotation axis of the circular tube, and the fixed length disc and the support can move and be locked relatively along the length direction of the circular tube.

Furthermore, the machine tool is characterized in that the transmission component is a screw rod, and the driving disc component is a sliding nut; the screw rod is arranged in parallel with the guide rail, two ends of the screw rod are respectively and rotationally connected with the seats fixedly connected with two ends of the guide rail, and the screw rod is driven to rotate by the power unit; an inner hole of the sliding nut is provided with an inner thread matched with the outer thread of the screw rod, the sliding nut is rotatably connected with the bracket, and the axis of the rotary connection is superposed with the center of the screw rod; when the support cannot move, the sliding nut rotates along with the screw rod, and the sliding nut drives the crank disc to rotate.

Furthermore, the machine tool is characterized in that a gear is arranged on the outer peripheral surface of the sliding nut, a gear is also arranged on the outer peripheral surface of the crank disc, and the sliding nut and the crank disc transmit rotary motion through gear meshing.

Further, the method for designing the machine tool is characterized in that the operation sequence design of the cutting device meets the following requirements:

1) with the rotation of the crank disc, the tool retreats and feeds in sequence from the moment when the tool is positioned at the nearest position, and the tool is not in contact with the circular tube in the time period of the tool retreating action to be finished and the tool feeding action to be started;

2) the moment when the push plate and the circular tube start to contact with each other for pushing materials cannot be earlier than the moment when the cutter reaches the nearest position;

3) the moment when the push plate is separated from the round tube cannot be earlier than the moment when the cutter is separated from the round tube in the cutter withdrawal stage and cannot be later than the moment when the cutter is contacted with the round tube in the cutter feeding stage.

The machine tool provided by the invention has the advantages of small error, high efficiency, simple structure and low cost when used for cutting round pipes into specified lengths in batches.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a perspective view of a machine tool;

FIG. 2 is an exploded view of the machine tool;

figure 3a is a view of the cutting device taken generally along direction a;

FIG. 3B is a view of the cutting device taken generally along direction B;

FIG. 4 is a side view of the cutting device;

FIG. 5 is a top view of the cutting device;

FIG. 6a is a perspective view of the cutting device advanced to a maximum position;

FIG. 6b is a cross-sectional view C-C of FIG. 4 with the cutting device advanced to a maximum position;

FIG. 6c is a cross-sectional view D-D of FIG. 4 with the cutting device advanced to a maximum position;

FIG. 7a is a perspective view of the cutting device during the pushing process;

FIG. 7b is a cross-sectional view C-C of FIG. 4 during the pushing of the cutting device;

FIG. 7c is a cross-sectional view D-D of FIG. 4 illustrating the pushing process of the cutting device;

FIG. 8a is a perspective view of the cutting device after pushing;

FIG. 8b is a cross-sectional view C-C of FIG. 4 with the cutting apparatus being pushed through;

FIG. 8c is a cross-sectional view D-D of FIG. 4 with the cutting apparatus being pushed through;

figure 9a shows a perspective view of the cutting device with the pusher plate about to come out of contact with the tube 3;

figure 9b is a cross-sectional view C-C of figure 4 with the push plate of the cutting device about to come out of contact with the tubular 3;

figure 9c is a cross-sectional view D-D of figure 4 with the push plate of the cutting device about to come out of contact with the tubular 3;

FIG. 10a is a perspective view of the cutting device with station feed completed;

FIG. 10b is a cross-sectional view C-C of FIG. 4 with the station feed of the cutting device completed;

FIG. 10c is a D-D cross-sectional view of FIG. 4 with the station feed of the cutting device completed;

FIG. 11 is a sequence diagram illustrating the operation of the cutting apparatus;

FIG. 12 is a perspective view of a machine tool according to a second embodiment;

FIG. 13 is an exploded view of the machine tool according to the second embodiment;

FIG. 14 is a perspective view of the cutting device of the second embodiment;

FIG. 15 is a side view of the cutting device of the second embodiment;

FIG. 16 is a plan view of the cutting device of the second embodiment;

FIG. 17 is a cross-sectional view E-E of FIG. 15;

fig. 18 is a sectional view F-F of fig. 15.

Labeled as:

1. a cutting device;

11. a guide rail; 111. a guide rail seat;

12. a support; 121. a slider; 122. a retainer; 123. pressing a plate;

13. a screw rod; 131. sliding and rotating the nut; 132. a power unit;

14. a crank disk; 141. a first crank; 142. a second crank;

15. a change wheel;

16. a cutter; 161. an extrusion disc; 162. a connecting rod; 163. a support wheel;

17. a material pushing rod; 171. pushing the plate; 172. a chute;

18. a fixed length disc;

19. a drive belt; 191. moving the rotating wheel;

2. a bed base; 21. a chuck;

3. a circular tube.

Detailed Description

The following detailed description of the embodiments of the present invention will be given with reference to the accompanying drawings for a purpose of helping those skilled in the art to more fully, accurately and deeply understand the concept and technical solution of the present invention and to facilitate its implementation.

As shown in fig. 1 and 2, the machine tool of the present invention comprises a bed 2 and a cutting device 1, wherein the bed 2 comprises a chuck 21, the chuck 21 is used for holding a round pipe 3, and the round pipe 3 is a round long tubular material to be cut into a required length; the chuck 21 drives the circular tube 3 to rotate around the axis of the chuck under the driving of the power source; the cutting device 1 is arranged on the bed base 2;

as shown in figures 1, 2, 3a, 3b, 4 and 5,

the cutting device 1 comprises a guide rail 11, a bracket 12, a cutter 16, a material pushing rod 17, a fixed length disc 18, a transmission component and a disc driving component matched with the transmission component; the guide rail 11 is fixedly connected with the bed base 2, the length direction of the guide rail 11 is parallel to the circular tube 3, and the support 12 moves along the guide rail 11;

the bracket 12 is sleeved on the far end (opposite to the chuck 21) of the round tube 3;

the cutter 16 is connected with the support 12 in a sliding manner, the material pushing rod 17 is connected with the support 12 in a sliding manner, the fixed length disc 18 is fixedly connected with the support 12, the fixed length disc 18 is in contact with the far end of the circular tube 3, and the distance between the cutting point of the cutter 16 and the fixed length disc 18 is the required cutting length of the circular tube 3;

the transmission component is driven by the power unit 132, the drive component driven by the transmission component enables the support 12 to move towards the chuck 21, when the fixed length disc 18 is contacted with the far end of the circular tube 3, the support 12 cannot move continuously, the transmission component drives the drive component to operate, and the drive component drives the cutter 16 to feed, so as to cut the circular tube 3; the disc driving member also drives the material pushing rod 17 to forcibly push out the intercepted round tube 3.

In particular, the method comprises the following steps of,

example one

As shown in fig. 1, fig. 2, fig. 3a, fig. 3b, fig. 4 and fig. 5, the cutting device 1 includes a guide rail 11, a bracket 12, a crank disc 14, a cutter 16, a material pushing rod 17, a fixed length disc 18, a transmission member and a disc driving member cooperating with the transmission member.

The guide rail 11 is fixedly connected with the bed base 2, the length direction of the guide rail 11 is parallel to the round tube 3, the support 12 moves along the linear direction guided by the guide rail 11, and the support 12 is sleeved at the far end (opposite to the chuck 21) of the round tube 3. More specifically, the guide rail 11 is a dovetail groove guide rail or a cylindrical linear guide rail, the bracket 12 is fixedly connected with the sliding block 121, and the sliding block 121 moves along the linear direction guided by the guide rail 11; when the lathe base 2 is a lathe, the guide rail 11 is fixedly connected with the guide rail base 111, and the guide rail base 111 is clamped by a small carriage of the lathe.

The cutter 16 is connected with the bracket 12 in a sliding mode, the sliding connection direction is the radial direction of the round pipe 3, a first end of the cutter 16 is connected with the extrusion disc 161 in a rotating mode, the rotating axis is parallel to the axis of the round pipe 3, and a second end of the cutter 16 is connected with a second end of the connecting rod 162 in a swinging mode. More specifically, the section of the cutter 16 is square, the wall of the bracket 12 is provided with a corresponding square through hole, a slight gap exists between the cutter 16 and the radial direction of the through hole on the wall of the bracket 12, and the cutter 16 slides in the through hole on the wall of the bracket 12; the material hardness of the extrusion disc 161 is high, the edge is sharp, the extrusion disc 161 rolls with the circumference of the same section of the round tube 3, and is extruded into the round tube 3 in the radial direction, namely, feeding, when the depth of feeding slightly exceeds the inner wall of the round tube 3 (because the material of the round tube 3 is deformed during extrusion, the actual feeding amount exceeds the position of the original inner wall), the round tube 3 is divided into a section with a specified length; in order that the axial position of the circular tube 3 is not moved when the extrusion disc 161 applies radial extrusion force to the circular tube 3, a support wheel 163 is further arranged at the opposite position of the extrusion disc 161, the support wheel 163 is connected with the bracket 12 through a roller frame, the roller frame can move and be locked relative to the bracket 12 so as to adapt to the circular tubes 3 with different outer diameters, and the support wheel 163 preferably comprises two rollers.

The crank disk 14 is rotationally connected with the bracket 12, the crank disk 14 has a circular outer peripheral surface, and a first crank 141 and a second crank 142 are arranged on the end surface of the crank disk 14; the first crank 141 is rotatably connected with the first end of the connecting rod 162, and the first crank 141 can be adjusted and locked along the radial direction of the crank disc 14 to adapt to circular tubes 3 with different outer diameters and wall thicknesses; the material pushing rod 17 is connected with the support 12 in a sliding mode, the preferred sliding direction is along the direction of a plumb line, the first end of the material pushing rod 17 is fixedly connected with the push plate 171, the push plate 171 and the first end of the material pushing rod 17 can move relatively and be locked along the direction of the plumb line so as to adapt to round pipes 3 with different outer diameters, one surface of the push plate 171, facing the chuck 21, is a plane, and the vertical height value of the plane needs to meet the requirement that the cross section projection of the whole pushing and resetting process of the push plate 171 and the round pipes 3 in the diameter range of the round pipes 3 is intersected; the second end of the material pushing rod 17 is provided with a sliding groove 172, the sliding groove 172 is connected with the second crank 142 on the crank disc 14 in a sliding manner, and the rotating radius of the second crank 142 is larger than the round pipe 3 with the maximum external diameter allowed by the cutting device 1.

The fixed length disc 18 is contacted with the far end of the round tube 3, and the distance between the cutting point of the cutter 16 and the fixed length disc 18 is the required cutting length of the round tube 3. More specifically, the fixed length disc 18 is rotatably connected with the support 12, the axis of the rotary connection coincides with the rotation axis of the circular tube 3, and the fixed length disc 18 and the support 12 can move and be locked relatively along the length direction of the circular tube 3 so as to meet the requirements of different cutting lengths of the circular tubes 3.

The transmission component is a screw rod 13, and the driving disc component is a sliding nut 131; the screw rod 13 is placed in parallel with the guide rail 11, two ends of the screw rod 13 are respectively and rotatably connected with seats fixedly connected with two ends of the guide rail 11, the screw rod 13 is driven to rotate by a power unit 132, the power unit 132 is preferably a motor and can also share a rotary power source with the chuck 21, and the outer surface of the sliding nut 131 is provided with threads; an inner hole of the sliding nut 131 is provided with an inner thread matched with the outer thread of the screw rod 13, the screw rod 13 is also rotatably connected with the bracket 12, and the axis of the rotary connection is superposed with the center of the screw rod 13; when the fixed-length disc 18 is in contact with the far end of the circular tube 3, the bracket 12 cannot move continuously, and the sliding nut 131 cannot move continuously along the axial direction of the screw rod 13, so that the sliding nut 131 rotates along with the screw rod 13, and the rotation of the sliding nut 131 drives the crank disc 14 to rotate, thereby driving the cutter 16 and the material pushing rod 17 to move, and realizing the fixed-length cutting of the circular tube 3; after the cut round tube 3 is pushed out, the fixed length disc 18 is no longer obstructed by the end face of the round tube 3, the force for preventing the sliding nut 131 from moving is released, the sliding nut 131 stops rotating due to the large rotating torque of the sliding nut 131, and the screw 13 drives the sliding nut 131 to move along the axial direction of the screw, that is, the bracket 12 moves along the linear direction guided by the guide rail 11 to the direction of the chuck 21. In more detail, the outer circumference of the slip nut 131 is provided with gears, the outer circumference of the crank disk 14 is also provided with gears, the gears transmit the rotation motion through the gear engagement, and in order to increase the driving torque of the crank disk 14, a speed changing wheel 15 is arranged between the crank disk 14 and the slip nut 131 to increase the transmission ratio; the sliding nut 131 and the crank disk 14 can also transmit motion through belt transmission, toothed belt transmission and the like. In order to stop the rotation of the slip nut 131 when the fixed length disc 18 does not contact the end surface of the round tube 3, the rotational resistance between the slip nut 131 and the bracket 12 may be increased, for example, the radial or axial gap between the slip nut 131 and the bracket 12 may be decreased, damping grease may be applied, or the lead of the external thread of the screw 13 may be decreased.

In addition, the holder 12 is provided with a retainer 122 having an inner diameter larger than that of the circular tube 3 in a direction facing the chuck 21, the inner diameter of the retainer 122 is larger than the outer diameter of the circular tube 3, and the circular tube 3 is cut by the cutter 16 after passing through the retainer 122; the retainer 122 serves to prevent the relatively long round tube 3 from being cut, and to limit the swing amplitude of the round tube 3.

The cutting principle of the cutting device 1 is explained in detail below in the following sequence of actions,

as shown in fig. 6a, 6b and 6c, the crank disc 14 drives the cutter 16 to move to the nearest position (i.e. the position closest to the round tube 3), and the crank disc 14 drives the push plate 171 to contact the round tube 3, at the same time, the round tube 3 is already divided into one segment with a predetermined length;

as shown in fig. 7a, 7b and 7c, the crank disc 14 continues to rotate to drive the cutter 16 to retreat away from the circular tube 3, and at the same time, the crank disc 14 drives the push plate 171 to press downwards to push out the part of the circular tube 3 that has been cut off forcibly (because the support 12 has a tendency to move towards the chuck 21, this tendency is converted into a force that the fixed-length disc 18 presses on the end surface of the circular tube 3, and this force makes the part of the circular tube 3 that has been cut off difficult to fall by gravity and must be pushed out forcibly);

as shown in fig. 8a, 8b and 8c, the crank disc 14 continues to rotate, which drives the cutter 16 to retract away from the circular tube 3, and at the same time, the crank disc 14 drives the push plate 171 to move down to the maximum pushing stroke (the maximum pushing stroke), and at this time, the cut portion of the circular tube 3 can be pushed out certainly; at the moment of pushing out the cut round tube 3, the resistance of the movement of the bracket 12 is released, and the bracket 12 drives the push plate 171 to move so that the side surface of the push plate 171 facing the chuck 21 is attached to the round tube 3;

as shown in fig. 9a, 9b and 9c, since the push plate 171 is attached to the circular tube 3, the bracket 12 is blocked by the circular tube 3 and cannot move further, the crank disk 14 continues to rotate, which drives the cutter 16 to retract away from the circular tube 3, and at the same time, the crank disk 14 drives the push plate 171 to move upwards until the push plate 171 is separated from the circular tube 3;

as shown in fig. 10a, 10b and 10c, the push plate 171 is separated from contact with the circular tube 3, the resistance of the movement of the support 12 is released, the support 12 drives the fixed length disc 18 to move so that the fixed length disc 18 is attached to the circular tube 3, the support 12 is blocked by the circular tube 3 and cannot move continuously, the crank disc 14 rotates, the cutter 16 is driven to feed and the material pushing rod 17 is driven to press downwards, the whole action is about to return to the state shown in fig. 6a, 6b and 6c, and the circular tube 3 is automatically cut next.

From the above operation sequence of the cutting principle of the cutting apparatus 1, the gist of the operation sequence can be summarized as shown in fig. 11,

as the crank disc 14 rotates, the tool 16 performs retracting and advancing operations in sequence from the time when the tool 16 is located at the closest position, and the tool 16 does not contact the circular tube 3, that is, the tool non-contact area shown in the figure, in the time period immediately before the tool retracting operation and immediately before the tool advancing operation;

the moment when the push plate 171 and the circular tube 3 start to contact with each other for pushing materials cannot be earlier than the moment when the cutter 16 reaches the nearest position; the moment when the push plate 171 is separated from the round tube 3 cannot be earlier than the moment when the cutter 16 is separated from the round tube 3 in the tool retracting stage and cannot be later than the moment when the cutter 16 is contacted with the round tube 3 in the tool feeding stage, so that the window period when the fixed-length disc 18 is contacted with the round tube 3 again, namely the window period when the support 12 finishes station feeding, can exist.

In the second embodiment, the first embodiment of the method,

as shown in fig. 12 to 18, the position of the power unit 132 is adaptively adjusted by replacing the screw 13 with the driving belt 19 and the sliding nut 131 with the moving wheel 191 in the above embodiment, and the cost advantage of the structure of the driving belt 19 for the long-distance driving with respect to the screw 13 is more obvious in the second embodiment.

The transmission component is a transmission belt 19, and the disc driving component is a transfer wheel 191; the transmission belt 19 is placed in parallel with the guide rail 11, two ends of the transmission belt 19 are respectively matched with output wheels of an idle wheel and a power unit 132, the idle wheel and the power unit 132 are arranged at two ends of the guide rail 11, the transmission belt 19 is driven by the power unit 132 to run, the power unit 132 is preferably a motor and can also share a power source for rotation with the chuck 21, the transmission belt 19 is preferably a toothed belt, and teeth are positioned on the inner circumferential surface;

the shifting wheel 191 is rotatably connected with the bracket 12, the axis of the rotary connection is vertical to the transmission belt 19, the peripheral surface of the shifting wheel 191 is provided with teeth, the shifting wheel 191 is arranged on the inner side of the transmission belt 19, and the teeth on the peripheral surface of the shifting wheel 191 are meshed with the teeth of the transmission belt 19; when the fixed-length disc 18 is in contact with the far end of the circular tube 3, the bracket 12 cannot move continuously, and the transfer wheel 191 cannot be pulled to move continuously by the transmission belt 19, so that the transfer wheel 191 is driven to rotate by the transmission belt 19, and the rotation of the transfer wheel 191 drives the crank disc 14 to rotate, so that the cutter 16 and the material pushing rod 17 are driven to move, and the fixed-length cutting of the circular tube 3 is realized; after the cut round tube 3 is pushed out, the fixed length disc 18 does not have the obstruction of the end surface of the round tube 3 any more, the force for preventing the moving wheel 191 from moving is removed, the rotating wheel 191 stops rotating due to the fact that the rotating torque of the moving wheel 191 is large, the transmission belt 19 pulls the moving wheel 191 to move axially along the guide rail 11, namely, the support 12 moves towards the chuck 21 along the linear direction guided by the guide rail 11; in order that the driving belt 19 can not be separated from the shifting wheel 191 due to radial force when the driving belt 19 pulls the shifting wheel 191, the pressing plate 123 is further fixedly connected to the bracket 12, the pressing plate 123 is arranged outside the meshing area of the driving belt 19 and the shifting wheel 191, a small gap is formed between the pressing plate 123 and the driving belt 19, when the driving belt 19 moves away from the shifting wheel 191, the pressing plate 123 can block the driving belt 19 and the shifting wheel 191, and the driving belt 19 and the shifting wheel 191 are always meshed. In more detail, the peripheral surface of the transfer wheel 191 is provided with bevel gears, the peripheral surface of the crank disk 14 is also provided with bevel gears, the bevel gears are meshed with each other to transmit rotary motion, in order to increase the driving torque of the crank disk 14, a change gear 15 is further arranged between the crank disk 14 and the slip nut 131 to increase the transmission ratio, and the input end and the output end of the change gear 15 are respectively provided with a cylindrical gear and a conical gear to realize 90-degree included angle transmission between the transfer wheel 191 and the crank disk 14.

It should be noted that, in order to stop the rotation of the rotating pulley 191 when the fixed length disc 18 is not in contact with the end surface of the circular tube 3, the rotation resistance between the rotating pulley 191 and the bracket 12 may be increased, for example, by reducing the radial or axial gap between the slip nut 131 and the bracket 12, and applying damping grease.

The power unit 132 described above is an electric motor, and may be a combination of a reduction mechanism and an electric motor; it is also possible that the rotation of the chuck 21 and the rotation of the transmission member share the same power unit 132.

The bed base 2 can also be directly a lathe, and the cutting device 1 is directly additionally arranged on the lathe, so that the additionally arranged lathe has the function of automatically cutting the round tube 3 with fixed length.

When the invention can also carry out the fixed length division of the strip-shaped materials with other sections, the rotation of the materials is not needed at the moment, the cutter 161 is changed into a power cutting head, such as a toothless saw or a toothed saw, and the like, the feeding stroke of the cutter 161 is increased, so that the formation of the cutter 161 is larger than the section width of the materials, and the cutting of the sections without autorotation can be realized.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, combination, improvement and the like made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A machine tool is characterized by comprising a bed seat (2) and a cutting device (1);

the bed seat (2) comprises a chuck (21), and the chuck (21) clamps the round pipe (3) to rotate;

the cutting device (1) is arranged on the bed base (2);

the cutting device (1) comprises a guide rail (11), a bracket (12), a cutter (16), a material pushing rod (17), a fixed-length disc (18), a transmission component and a disc driving component matched with the transmission component;

the guide rail (11) is fixedly connected with the bed base (2), the length direction of the guide rail (11) is parallel to the round pipe (3), and the bracket (12) moves along the guide rail (11);

the bracket (12) is sleeved at the far end of the round pipe (3);

the cutter (16) is connected with the bracket (12) in a sliding way, the material pushing rod (17) is connected with the bracket (12) in a sliding way, the fixed length disc (18) is fixedly connected with the bracket (12), and the fixed length disc (18) is contacted with the far end of the circular tube (3);

the driving disc component driven by the transmission component enables the support (12) to move towards the chuck (21), when the fixed length disc (18) is in contact with the far end of the circular tube (3), the support (12) cannot move continuously, the transmission component drives the driving disc component to operate, the driving disc component drives the cutter (16) to feed, and the circular tube (3) is cut; the disc driving component drives the material pushing rod (17) to push out the intercepted circular tube (3).

2. A machine tool according to claim 1, characterized in that the tool (16) is slidably connected to the support (12) in the direction of the radius of the tube (3), the tool (16) being rotatably connected at a first end to the pressing plate (161) with an axis parallel to the axis of the tube (3), and the tool (16) being pivotably connected at a second end to the connecting rod (162).

3. A machine tool according to claim 2, characterized in that support wheels (163) are provided at opposite positions of the pressing plate (161), the support wheels (163) being connected to the frame (12) via a roller carriage.

4. A machine tool according to claim 2, wherein the crank disk (14) is rotatably connected to the frame (12), the crank disk (14) having a circular outer peripheral surface, the crank disk (14) being provided with a first crank (141) and a second crank (142) on its end surface; the first crank (141) is rotatably connected to a first end of the connecting rod (162).

5. A machine tool according to claim 4, characterized in that the pusher (17) is slidably connected to the support (12), the first end of the pusher (17) being fixedly connected to the pusher (171);

the second end of the material pushing rod (17) is provided with a sliding chute (172), and the sliding chute (172) is connected with a second crank (142) on the crank disc (14) in a sliding manner.

6. A machine tool according to claim 5, characterized in that the face of the pusher (171) facing the chuck (21) is a plane which intersects the projection of the section of the barrel (3) during the entire pushing and resetting of the pusher (171).

7. A machine tool according to claim 1, characterized in that the fixed length disc (18) is rotatably connected to the support (12) with the axis of rotation coinciding with the axis of rotation of the tubular (3), the fixed length disc (18) and the support (12) being able to be moved and locked relative to each other along the length of the tubular (3).

8. A machine tool according to claim 1, wherein the transmission member is a screw (13), the drive member is a slip nut (131);

the screw rod (13) is arranged in parallel with the guide rail (11), two ends of the screw rod (13) are respectively and rotatably connected with seats fixedly connected with two ends of the guide rail (11), and the screw rod (13) is driven to rotate by the power unit (132);

an inner hole of the sliding nut (131) is provided with an inner thread matched with the outer thread of the screw rod (13), the sliding nut (131) is rotatably connected with the bracket (12), and the axis of the rotary connection is superposed with the center of the screw rod (13);

when the bracket (12) can not move, the sliding nut (131) rotates along with the screw rod (13), and the sliding nut (131) drives the crank disc (14) to rotate.

9. A machine tool according to claim 8, characterized in that the outer circumference of the slip nut (131) is provided with a gear and the outer circumference of the crank disk (14) is also provided with a gear, the slip nut (131) and the crank disk (14) transmitting the rotational movement by means of gear engagement.

10. A method for designing a machine tool according to any one of claims 1 to 9, characterized in that the sequence of actions of the cutting device (1) is designed to meet the following requirements:

1) with the rotation of the crank disc (14), the tool (16) sequentially performs tool retracting and tool feeding actions from the moment when the tool (16) is positioned at the nearest position, and the tool (16) is not in contact with the circular tube (3) in the time period of the tool retracting action to be finished and the tool feeding action to be started;

2) the moment when the push plate (171) and the circular tube (3) start to contact with each other for pushing materials cannot be earlier than the moment when the cutter (16) reaches the nearest position;

3) the moment when the push plate (171) is separated from the round tube (3) cannot be earlier than the moment when the cutter (16) is separated from the round tube (3) in the tool withdrawal stage and cannot be later than the moment when the cutter (16) is contacted with the round tube (3) in the tool feeding stage.