A self-positioning four-point positioning device

Abstract

The invention discloses a self-positioning four-point positioning device in the technical field of lathe processing, comprising an inner guide plate fixed on a machine tool, one end of the inner guide plate in the left-right direction is connected with a baffle plate, two guide openings arranged at intervals in the height direction are opened on the baffle plate, the upper and lower parts of the inner guide plate are respectively connected with an upper inclined wedge and a lower inclined wedge which can slide in the height direction and are arranged relatively in the height direction, the upper inclined wedge extending out of the baffle plate is connected with two upper clamping rollers arranged at intervals in the left-right direction, the lower inclined wedge extending out of the baffle plate is connected with two lower clamping rollers arranged at intervals in the left-right direction, a driving component for driving the upper guide part and the lower guide part to move synchronously in opposite directions is connected to the inner guide plate, and the two upper clamping rollers and the lower clamping rollers can clamp the workpiece; point contact is achieved during clamping and positioning, and the clamping is reliable.

Description

Technical Field

[0001] The invention belongs to the technical field of lathe processing, and in particular relates to a self-positioning four-point positioning device. Background Art

[0002] When processing slender shafts, a three-jaw chuck is usually used to clamp one end of the shaft. However, due to the poor rigidity of the slender shaft, it is easily vibrated by the cutting force of the tool during the processing, affecting the processing quality and precision of the workpiece surface. Therefore, a center stand is needed to assist in clamping and positioning it. However, the positioning diameter of the traditional positioning device needs to be fixed in advance and cannot be changed during the processing. Its position may need to be changed multiple times during the processing. It is also difficult to position and clamp some tapered slender shaft workpieces, which has great limitations. Summary of the invention

[0003] In view of the defects in the prior art, the purpose of the present invention is to solve the technical problem of difficult positioning and clamping in the above-mentioned prior art, and to provide a self-positioning four-point positioning device. The present invention realizes point contact during clamping and positioning, and the clamping is reliable and the friction is reduced.

[0004] The object of the present invention is achieved in this way: a self-positioning four-point positioning device comprises an inner guide plate fixed on a machine tool, one end of the inner guide plate in the left-right direction is connected to a baffle plate, the baffle plate is provided with two guide openings spaced apart in the height direction, the upper and lower parts of the inner guide plate are respectively connected with an upper inclined wedge and a lower inclined wedge which can slide in the height direction and are arranged opposite to each other in the height direction, the upper inclined wedge comprises a liftable upper guide part, an upper connecting part is provided on the side of the upper guide part facing inward relative to the baffle plate, an end of the upper connecting part away from the upper guide part horizontally extends out of the baffle plate along the upper guide opening, and the lower inclined wedge comprises a liftable lower guide part The guide part, the lower guide part is provided with a lower connecting part at one end facing inward relative to the baffle, and the end of the lower connecting part away from the lower guide part horizontally extends out of the baffle along the lower guide opening, and the inner guide plate is connected with a driving component that drives the upper guide part and the lower guide part to move synchronously in opposite directions, the upper connecting part is connected with an upper connecting seat extending downward, and the lower connecting part is connected with a lower connecting seat extending upward, the upper connecting seat is connected with two upper clamping rollers arranged at intervals in the left and right directions, and the lower connecting seat is connected with two lower clamping rollers arranged at intervals in the left and right directions, and the two upper clamping rollers and the lower clamping roller can clamp the workpiece.

[0005] In the present invention, the upper connecting part can be raised and lowered in the upper guide opening, and the lower connecting part can be raised and lowered in the lower guide opening; the driving component is actuated to make the upper guide part and the lower guide part move upward and downward synchronously respectively, and the positioning radius between the upper clamping roller and the lower clamping roller is expanded, and the workpiece to be processed is placed, and the driving component reverses and the upper clamping roller moves downward, and the lower clamping roller moves upward at the same time, and the positioning radius is reduced until the workpiece to be processed is clamped, and the driving component stops. During the cutting process of the workpiece, point contact is formed between the two upper clamping rollers and the two lower clamping rollers and the workpiece, thereby reducing friction and improving the processing quality of the workpiece surface; it can be applied to the work of positioning the workpiece during processing.

[0006] In order to realize the lifting and lowering of the upper guide part and the lower guide part, the driving assembly includes a moving block slidably connected to the inner guide plate, and the moving block can slide horizontally in the left and right directions. The upper end of the moving block can just slide along the inclined surface of the upper guide part toward the upper end, and the lower end of the moving block can just slide along the inclined surface of the lower guide part toward the lower end.

[0007] In order to improve the reliability of the lifting and lowering of the upper guide part and the lower guide part, the upper and lower ends of the moving block are fixedly connected with inclined guide plates, the upper inclined guide plate is attached to the inclined surface of the upper guide part, and the lower inclined guide plate is attached to the inclined surface of the lower guide part.

[0008] In order to further improve the reliability of the lifting and lowering of the upper guide part and the lower guide part, the upper guide part and the lower guide part are respectively provided with an upper sliding groove and a lower sliding groove which are inclined. The upper guide part is slidably provided with an upper limit guide block via the upper sliding groove, and the lower guide part is slidably provided with a lower limit guide block via the lower sliding groove. The upper part of the moving block is connected to the upper limit guide block, and the lower part of the moving block is connected to the lower limit guide block. The sliding direction of the upper limit guide block is parallel to the direction of the inclined surface of the upper guide part, and the sliding direction of the lower limit guide block is parallel to the direction of the inclined surface of the lower guide part.

[0009] The cam is connected to the upper and lower inner guide plates of the moving block, respectively, and a linear drive is fixedly connected to the linear drive, and a driving rod is connected to the linear drive, which can extend toward the other end of the inner guide plate in the left and right directions and can make reciprocating linear movements in the left and right directions. The outer ends of the two driving rods are connected to a crossbeam push rod, and a connecting groove is provided at one end of the moving block relative to the crossbeam push rod, and the end of the beam push rod extending in the direction of the moving block is inserted into the connecting groove, and a sliding groove is provided on the crossbeam push rod, and a connecting hole is provided at the end of the moving block away from the upper inclined wedge, and a connecting pin is used to pass through the connecting hole and the sliding groove in sequence. The groove connects the moving block and the beam push rod together; in this design, the front linear drive is used to move the drive rod continuously outward. When the shortest end of the sliding groove in the beam push rod contacts the connecting pin, the moving block can move horizontally to the right under the action of the beam push rod. The moving block generates an upward oblique component force on the upper sliding groove of the upper inclined wedge and a downward oblique component force on the lower sliding groove of the lower inclined wedge, so that the upper inclined wedge moves vertically upward and the lower inclined wedge moves vertically downward. The upper inclined wedge and the lower inclined wedge respectively drive the upper clamping roller and the lower clamping roller to move, thereby realizing the expansion of the positioning radius formed between the upper clamping roller and the lower clamping roller.

[0010] In order to further realize the automatic positioning of the workpiece, the upper limit guide block and the lower limit guide block are respectively fixedly connected to the top plate on one side facing outward, the top plate is connected to a guide rod, and a return spring is sleeved on the guide rod. The inner guide plate facing outward at one end of the top plate relative to the crossbeam push rod is connected to two guide support blocks spaced apart in the height direction, and a guide hole is opened on the guide support block, and the guide rod can slide horizontally along the corresponding guide holes in the left and right directions respectively, and the return spring is between the top plate and the guide support block; in this design, when the connecting pin contacts the leftmost end of the slide slot, the return spring is in a compressed state, and the slender rod is pressed During clamping, the linear drive acts in the opposite direction, the driving rod moves to the left, and the moving block is only subjected to the elastic force of the reset spring. The moving block moves horizontally to the left under the action of the reset spring. The inclined guide plate at the upper end of the moving block will produce an inclined downward component force on the inclined surface of the upper inclined wedge, and the inclined guide plate at the lower end of the moving block will produce an inclined upward component force on the inclined surface of the lower inclined wedge, so that the upper inclined wedge moves vertically downward and the lower inclined wedge moves vertically upward until the workpiece is clamped. During the processing, if the contour radius of the workpiece increases, the reset spring will be compressed by force to expand the positioning radius. If the contour radius of the workpiece decreases, the reset spring will automatically reset to reduce the positioning radius.

[0011] In order to further improve the stability of the lifting and lowering of the upper inclined wedge and the lower inclined wedge, the upper part of the inner guide plate is fixedly connected to the upper fixed seat, and the lower part of the inner guide plate is fixedly connected to the lower fixed seat. The upper fixed seat is provided with an upper lifting groove, and the lower fixed seat is provided with a lower lifting groove. The upper fixed seat is slidably connected to the upper slider via the upper lifting groove, and the lower fixed seat is slidably connected to the lower slider via the lower lifting groove. The upper guide part is fixedly connected to the upper slider, and the lower guide part is fixedly connected to the lower slider.

[0012] In order to further achieve synchronous reverse movement of the upper inclined wedge and the lower inclined wedge, the upper inclined wedge and the lower inclined wedge are symmetrically arranged about the center of the moving block in the height direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is the front view of the present invention.

[0014] Figure 2 The three-dimensional structure of the present invention Figure 1 .

[0015] Figure 3 for Figure 2 A partial enlarged view of point A in the middle.

[0016] Figure 4 The three-dimensional structure of the present invention Figure 2 .

[0017] Figure 5 for Figure 4 A partial enlarged view of point B in the middle.

[0018] Figure 6 for Figure 4 A partial enlarged view of point C in the middle.

[0019] Among them, 1 is a lower inclined wedge, 101 is a lower guide part, 102 is a lower connecting part, 2 is a lower connecting seat, 3 is a lower clamping roller, 4 is an upper clamping roller, 5 is an upper connecting seat, 6 is an upper inclined wedge, 601 is an upper connecting part, 602 is an upper guide part, 7 is a driving assembly, 701 is a guide rod, 702 is a linear drive, 703 is a moving block, 704 is a guide rail, 705 is a crossbeam push rod, 706 is a slide groove, 707 is a connecting pin, 708 is a return spring, 709 is an inclined guide plate, 710 is a top plate, 711 is a guide support block, 712 is a guide hole, 8 is an inner guide plate, 9 is a baffle, 10 is an upper sliding groove, 11 is a lower sliding groove, 12 is an upper limit guide block, 13 is a lower slider, 14 is a lower fixed seat, 15 is an upper fixed seat, 16 is an upper slider, 17 is a lower limit guide block, 18 is a lower lifting groove, and 19 is a guide opening. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the accompanying drawings.

[0021] like Figure 1 to Figure 6The self-positioning four-point positioning device shown in the figure comprises an inner guide plate 8 fixed on a machine tool, one end of the inner guide plate 8 in the left-right direction is connected to a baffle plate 9, two guide openings 19 arranged at intervals in the height direction are opened on the baffle plate 9, the upper and lower parts of the inner guide plate 8 are respectively connected to an upper inclined wedge 6 and a lower inclined wedge 1 which can slide in the height direction and are arranged opposite to each other in the height direction, the upper inclined wedge 6 comprises an upper guide part 602 which can be lifted and lowered, an upper connecting part 601 is arranged on the side of the upper guide part 602 which faces inward relative to the baffle plate 9, and an end of the upper connecting part 601 which is away from the upper guide part 602 horizontally extends out of the baffle plate 9 along the upper guide opening 19, and the lower inclined wedge 1 comprises a lower guide part 101 which can be lifted and lowered, and the lower guide part 101 is arranged on the side of the upper guide part 602 which faces inward relative to the baffle plate 9, and the upper connecting part 601 extends horizontally ... A lower connecting portion 102 is provided at the end of the portion 101 facing inward relative to the baffle 9, and one end of the lower connecting portion 102 away from the lower guide portion 101 extends horizontally out of the baffle 9 along the guide opening 19 below. The inner guide plate 8 is connected with a driving component 7 for driving the upper guide portion 602 and the lower guide portion 101 to move synchronously in opposite directions, the upper connecting portion 601 is connected with an upper connecting seat 5 extending downward, the lower connecting portion 102 is connected with a lower connecting seat 2 extending upward, the upper connecting seat 5 is connected with two upper clamping rollers 4 arranged at intervals in the left-right direction, and the lower connecting seat 2 is connected with two lower clamping rollers 3 arranged at intervals in the left-right direction, and the two upper clamping rollers 4 and the lower clamping roller 3 can clamp the workpiece.

[0022] In order to realize the lifting and lowering of the upper guide part 602 and the lower guide part 101, the driving assembly 7 includes a moving block 703 slidably connected to the inner guide plate 8, the moving block 703 can slide horizontally in the left and right directions, and the inner guide plate 8 is fixedly connected with a guide rail 704, and the moving block 703 is slidably connected to the guide rail 704, and the upper end of the moving block 703 can just slide along the inclined surface of the upper guide part 602 toward the upper end, and at the same time, the lower end of the moving block 703 can just slide along the inclined surface of the lower guide part 101 toward the lower end, and the upper and lower ends of the moving block 703 are fixedly connected with inclined guide plates 709, and the inclined guide plates 709 are made of brass to reduce the friction between the moving block 703 and the inclined wedge. The upper inclined guide plate 709 is attached to the inclined surface of the upper guide part 602, and the lower inclined guide plate 709 is attached to the inclined surface of the upper guide part 602. The inclined guide plate 709 is attached to the inclined surface of the lower guide part 101; the upper guide part 602 and the lower guide part 101 are respectively provided with an upper sliding groove 10 and a lower sliding groove 11 which are inclined, the upper guide part 602 is slidably provided with an upper limit guide block 12 through the upper sliding groove 10, and the lower guide part 101 is slidably provided with a lower limit guide block 17 through the lower sliding groove 11, the upper part of the moving block 703 is connected to the upper limit guide block 12, and the lower part of the moving block 703 is connected to the lower limit guide block 17, the sliding direction of the upper limit guide block 12 is parallel to the direction of the inclined surface of the upper guide part 602, and the sliding direction of the lower limit guide block 17 is parallel to the direction of the inclined surface of the lower guide part 101; the upper inclined wedge 6 and the lower inclined wedge 1 are symmetrically arranged about the center of the moving block 703 in the height direction.

[0023] In order to further realize the movement of the moving block 703, a linear drive 702 is fixedly connected to the inner guide plates 8 above and below the moving block 703, respectively. The linear drive 702 is preferably an electric push rod. The linear drive 702 is connected to a driving rod which can extend toward the other end of the inner guide plate 8 in the left and right directions and can make reciprocating linear movements in the left and right directions. The outer ends of the two driving rods are connected to a beam push rod 705. A connecting groove is provided at one end of the moving block 703 opposite to the beam push rod 705. The end of the beam push rod 705 extending in the direction of the moving block 703 is inserted into the connecting groove. A slide groove 706 is provided on the beam push rod 705. A connecting hole is provided at the end of the moving block 703 away from the upper inclined wedge 6. A connecting pin 707 is used to pass through the connecting hole and the slide groove 706 in sequence to connect the moving block 703 and the beam push rod 705 together.

[0024] In order to further improve the stability of the lifting and lowering of the upper inclined wedge 6 and the lower inclined wedge 1, the upper part of the inner guide plate 8 is fixedly connected to the upper fixed seat 15, and the lower part of the inner guide plate 8 is fixedly connected to the lower fixed seat 14. The upper fixed seat 15 is provided with an upper lifting groove, and the lower fixed seat 14 is provided with a lower lifting groove 18. The upper fixed seat 15 is slidably connected to the upper slider 16 via the upper lifting groove, and the lower fixed seat 14 is slidably connected to the lower slider 13 via the lower lifting groove 18. The upper guide part 602 is fixedly connected to the upper slider 16, and the lower guide part 101 is fixedly connected to the lower slider 13.

[0025] In order to further realize the automatic positioning of the workpiece, the upper limit guide block 12 and the lower limit guide block 17 are fixedly connected to the outward side with a top plate 710, the top plate 710 is connected to a guide rod 701, and the guide rod 701 is provided with a reset spring 708. The top plate 710 is connected to the inner guide plate 8 facing outward at one end of the crossbeam push rod 705, and two guide support blocks 711 are connected to the inner guide plate 8 at an interval in the height direction. The guide support block 711 is provided with a guide hole 712, and the guide rod 701 can slide horizontally along the corresponding guide hole 712 in the left and right directions, and the reset spring 708 is between the top plate 710 and the guide support block 711.

[0026] In the present invention, the upper connecting part 601 can be raised and lowered in the upper guide opening 19, and the lower connecting part 102 can be raised and lowered in the lower guide opening 19. The upper clamping roller 4 and the lower clamping roller 3 are preferably made of nylon. The inner guide plate 8 is first installed and fixed on the machine tool guide rail 704, and at the same time cooperates with the tool changer so that it can slide along the machine tool guide rail 704 with the turning tool. Before use, the linear driver 702 is actuated to extend the driving rod to the right, and the beam push rod 705 is pushed to the right horizontally. When the leftmost end of the slide groove 706 in the beam push rod 705 contacts the connecting pin 707, the moving block 703 can be moved on the beam push rod 705. The upper limit guide block 12 connected to the moving block 703 and embedded in the upper sliding groove 10 will move horizontally to the right under the action of the moving block 703. At this time, the upper limit guide block 12 will generate an oblique upward component force on the upper sliding groove 10 on the upper inclined wedge 6, so that the upper inclined wedge 6 and the upper limit guide block 12 connected thereto move vertically upward. Similarly, the lower inclined wedge 1 and the lower limit guide block 17 connected thereto move vertically downward to achieve the expansion of the positioning radius. When the slender rod is clamped by the present invention, the linear drive 702 is reversed. The upper inclined surface guide plate 709 on the movable block 703 will generate an oblique downward force on the upper surface of the upper inclined wedge 6, so that the upper inclined wedge 6 and the upper limit guide block 12 connected thereto move vertically downward along the upper lifting groove fixed on the inner guide plate 8. Similarly, the lower inclined wedge 1 and the lower limit guide block 17 connected thereto move vertically upward along the lower lifting groove 18 fixed on the inner guide plate 8, the upper clamping roller 4 moves downward, and the lower clamping roller 3 moves upward until the workpiece is clamped. During the machining process, if the contour radius of the workpiece increases, the reset spring 708 will be compressed by force to expand the positioning radius, and if the contour radius of the workpiece decreases, the reset spring 708 will automatically reset to reduce the positioning radius. The present invention has an ingenious structure and can automatically position and clamp the workpiece, and can automatically change the positioning radius according to the contour changes of the workpiece, saving the time of repeated clamping and positioning processes and greatly improving production efficiency. During the working process, the two upper clamping rollers 4 and the two lower clamping rollers 3 form point contact with the workpiece, reducing friction and improving the machining quality of the workpiece surface. It can be used to position the workpiece during machining.

[0027] The present invention is not limited to the above-mentioned embodiments. On the basis of the technical solution disclosed in the present invention, technicians in this field can make some substitutions and deformations to some technical features therein according to the disclosed technical content without creative labor, and these substitutions and deformations are all within the protection scope of the present invention.

Claims

1. A self-positioning four-point positioning device, characterized in that: The invention comprises an inner guide plate fixed on a machine tool, wherein one end of the inner guide plate in the left-right direction is connected to a baffle plate, and the baffle plate is provided with two guide openings spaced apart in the height direction, and the upper and lower parts of the inner guide plate are respectively connected with an upper inclined wedge and a lower inclined wedge which can slide in the height direction and are arranged opposite to each other in the height direction, and the upper inclined wedge comprises an upper guide part which can be lifted and lowered, and an upper connecting part is arranged on the side of the upper guide part facing inward relative to the baffle plate, and an end of the upper connecting part away from the upper guide part horizontally extends out of the baffle plate along the upper guide opening, and the lower inclined wedge comprises a lower guide part which can be lifted and lowered, and a lower connecting part is arranged on the end of the lower guide part facing inward relative to the baffle plate, and the lower connecting part The cam is connected to the guide plate to move the upper and lower guide parts in opposite directions synchronously, and the upper connecting part is connected to an upper connecting seat extending downward, and the lower connecting part is connected to a lower connecting seat extending upward, and the upper connecting seat is connected to two upper clamping rollers spaced apart in the left and right directions, and the lower connecting seat is connected to two lower clamping rollers spaced apart in the left and right directions. The two upper clamping rollers and the lower clamping rollers can clamp the workpiece, and the driving assembly includes a moving block slidably connected to the inner guide plate, and the upper The inner guide plates on the upper and lower sides are respectively fixedly connected with linear drivers, and the linear drivers are connected with a driving rod which can extend toward the other end of the inner guide plate in the left and right directions and can make reciprocating linear movements in the left and right directions. The outer ends of the two driving rods are connected with a crossbeam push rod, and a connecting groove is formed at one end of the moving block relative to the crossbeam push rod, and the end of the crossbeam push rod extending in the direction of the moving block is inserted into the connecting groove, and a slide groove is formed on the crossbeam push rod. A connecting hole is formed at the end of the moving block away from the upper inclined wedge, and a connecting pin is used to pass through the connecting hole and the slide groove in sequence to connect the moving block and the crossbeam push rod together, and inclined grooves are respectively formed on the upper guide part and the lower guide part. An upper sliding groove and a lower sliding groove are set, the upper guide part is slidably provided with an upper limit guide block through the upper sliding groove, and the lower guide part is slidably provided with a lower limit guide block through the lower sliding groove, the upper limit guide block and the lower limit guide block are fixedly connected to the top plate on the outward side respectively, the top plate is connected to a guide rod, and a return spring is mounted on the guide rod, and two guide support blocks spaced apart in the height direction are connected to the inner guide plate at one end of the top plate relative to the crossbeam push rod facing outward, the guide support block is provided with a guide hole, the guide rod can slide horizontally along the corresponding guide hole in the left and right directions respectively, and the return spring is between the top plate and the guide support block.

2. A self-positioning four-point positioning device according to claim 1, characterized in that: The moving block can slide horizontally in the left and right directions, and the upper end of the moving block can slide along the inclined surface of the upper guide part toward the upper end, while the lower end of the moving block can slide along the inclined surface of the lower guide part toward the lower end.

3. A self-positioning four-point positioning device according to claim 2, characterized in that: The upper and lower ends of the moving block are both fixedly connected with inclined guide plates, the upper inclined guide plate is attached to the inclined surface of the upper guide part, and the lower inclined guide plate is attached to the inclined surface of the lower guide part.

4. A self-positioning four-point positioning device according to claim 3, characterized in that: The upper part of the moving block is connected to the upper limit guide block, and the lower part of the moving block is connected to the lower limit guide block. The sliding direction of the upper limit guide block is parallel to the direction of the inclined surface of the upper guide part, and the sliding direction of the lower limit guide block is parallel to the direction of the inclined surface of the lower guide part.

5. A self-positioning four-point positioning device according to claim 3, characterized in that: The upper part of the inner guide plate is fixedly connected to an upper fixed seat, and the lower part of the inner guide plate is fixedly connected to a lower fixed seat. An upper lifting groove is opened on the upper fixed seat, and a lower lifting groove is opened on the lower fixed seat. The upper fixed seat is slidably connected to an upper slider via the upper lifting groove, and the lower fixed seat is slidably connected to a lower slider via the lower lifting groove. The upper guide part is fixedly connected to the upper slider, and the lower guide part is fixedly connected to the lower slider.

6. A self-positioning four-point positioning device according to any one of claims 1 to 5, characterized in that: The upper inclined wedge and the lower inclined wedge are symmetrically arranged about the center of the moving block in the height direction.

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