A clamp for fixing claw-type workpieces

Abstract

This application provides a clamping fixture for fixed claw-type workpieces. It achieves accurate positioning of the workpiece body through six-point positioning: three positioning blocks at the bottom of the workpiece, two positioning blocks on the outer side of the U-shaped opening end of the workpiece, and a positioning structure at the top of the workpiece head. The workpiece is vertically clamped by the cooperation of the clamping structure and the bottom positioning structure. The workpiece is clamped in both the head and tail directions by the cooperation of the tail side positioning structure and the head clamping structure. Finally, the arc segment and the opening end of the U-shaped opening are clamped in both directions by the cooperation of the head side positioning structure and the top clamping structure, ensuring stability during workpiece processing and improving processing accuracy.

Description

Technical Field

[0001] This utility model relates to the field of tooling and fixture technology, specifically a fixture for fixing claw-type workpieces. Background Technology

[0002] like Figure 1 The image shows a fixed claw-type workpiece used in engineering machinery. The workpiece body includes a head a1 and a tail a2. A first through hole a3, a second through hole a4, and a U-shaped opening a5 need to be machined on the head a1, and a third through hole a6 and a through groove a7 need to be machined on the tail a2. The top of the head a1, where the first through hole a3 is located, is flat. The first through hole a3 and the second through hole a4 are coaxial through holes. The through groove a7 is an open groove opened laterally along the inner cavity of the tail a2, and the upper and lower side walls of the through groove a7 have the same thickness. The third through hole a6 is simultaneously opened on both sides of the through groove a7, and the axis of the third through hole a6 is perpendicular to the side wall of the through groove a7. Because the structure of the workpiece to be processed is relatively complex and has high machining accuracy requirements, a 5-axis CNC machine tool is required for processing. However, because the shape of the workpiece is irregular, and there are many parts to be processed on the workpiece, and their positions are relatively complex, how to design a fixture to cooperate with the CNC machine tool becomes a problem that needs to be solved. Summary of the Invention

[0003] To address the problem that there are no suitable fixtures for fixing claw-type workpieces in the existing technology, this utility model provides a fixture for fixing claw-type workpieces, which can achieve precise positioning and clamping of workpieces during CNC machine tool processing, thereby achieving high-precision machining.

[0004] The structure of this utility model is as follows: a clamp for fixing claw-type workpieces, characterized in that it includes: a base, a positioning structure, and a clamping structure; the positioning structure and the clamping structure are disposed on the base; The positioning structure includes: a bottom positioning structure, a tail side positioning structure, and a head side positioning structure; The bottom positioning structure includes: a head bottom end face positioning block and a tail bottom end face positioning block. At least two head bottom end face positioning blocks are provided, respectively located at the opening end of the U-shaped opening away from the tail of the workpiece and at the apex of the U-shaped opening. The tail bottom end face positioning block is located at the end of the tail of the workpiece. The tail side positioning structure is located on the outer side of the tail at the position furthest from the head; The head side positioning structure includes a rectangular positioning block, which is set on the side of the opening end of the U-shaped opening of the workpiece. A U-shaped clearance opening of the same size is opened on the rectangular positioning block, and the two opening ends of the U-shaped clearance opening are set opposite to the two opening ends of the U-shaped opening to be processed on the workpiece. The clamping structure includes: a pressing structure, a head clamping structure, and a U-shaped opening top clamping structure; The clamping structure includes a clamping plate and a clamping drive structure. The clamping plate includes an integrally formed U-shaped head and a straight plate-shaped tail. The U-shaped head is adapted to the size of the U-shaped opening on the workpiece, and the tail is connected to the clamping drive structure. The clamping plate clamps the workpiece from the top around the U-shaped opening of the workpiece through the clamping drive structure. The head clamping structure includes: a clamping head and a first clamping drive structure; the clamping head is located on the outer side of the workpiece head at the position furthest from the workpiece tail, and the clamping head is located away from the machining position of the first through hole on the workpiece; the clamping head applies clamping force to the workpiece from the horizontal direction through the first clamping drive structure. The U-shaped opening top clamping structure includes a clamping joint and a clamping drive structure. The clamping joint is located on the outside of the U-shaped opening arc segment of the workpiece, and the clamping structure applies a horizontal clamping force to the U-shaped opening arc segment of the workpiece under the action of the clamping drive structure.

[0005] Its further features are: The base includes: a horizontally arranged base plate and a vertically arranged connecting plate, the base plate and the connecting plate forming a U-shaped structure, and the positioning structure and the clamping structure are installed on the base plate; The first clamping drive structure includes: a horizontal drive structure, a connector, a mounting plate, a clamping plate, and a rotating shaft; A mounting groove for tightening is provided on the base plate; The mounting plate includes a horizontal plate and a vertical plate, which are arranged in an L-shape with the horizontal plate on top and the vertical plate on the bottom; the two mounting plates are inserted into the inner cavity of the mounting groove for tightening with the vertical plates facing each other, and the horizontal plate is fixed on the base plate. The rotating shaft is horizontally positioned between two mounting plates in a direction perpendicular to the axis of the first through hole of the workpiece. A vertical plate is fixedly connected to each end of the rotating shaft. The top end of the clamping plate is provided with the clamping head facing the workpiece, and the bottom end extends through the mounting groove to the bottom plate. The middle part of the clamping plate is movably fitted onto the rotating shaft. The horizontal drive structure is disposed below the base plate, and the output end of the horizontal drive structure is parallel to the axis of the first through hole of the workpiece; the connector is mounted on the output end of the horizontal drive structure; the connector is horizontally disposed on the side of the end of the clamping plate. The height of the tail bottom end positioning block is less than the inlet height of the workpiece tail through groove placed on the bottom positioning structure; The head bottom end face positioning block and the tail bottom end face positioning block are at the same height; The clamping head of the head clamping structure is an arc-shaped plate structure that forms a line contact with the side wall of the workpiece; The clamping joint is provided in two parts. The two clamping joints are symmetrically arranged on the outside of the arc segment of the U-shaped opening of the workpiece with the perpendicular bisector of the two opening ends of the workpiece as the symmetry. The included angle between the two clamping joints is 60 degrees. It also includes: a connecting flange, wherein one end of the connecting plate is connected to the base plate and the other end is connected to the flange.

[0006] This application provides a clamping fixture for fixed claw-type workpieces. It employs a six-point positioning system: three positioning blocks at the bottom of the workpiece, two positioning blocks on the outer side of the U-shaped opening, and a positioning structure at the top of the workpiece head. The workpiece is accurately positioned vertically by a clamping structure and a bottom positioning structure. A tail-side positioning structure and a head-tightening structure clamp the workpiece in both head and tail directions. A head-side positioning structure and a U-shaped opening-tightening structure clamp the arc segment and opening of the U-shaped opening, ensuring stability and improving machining accuracy. A U-shaped clearance on the head-side positioning structure allows for simultaneous U-shaped opening machining while clamping the workpiece. The use of two positioning blocks on the bottom of the head, along with the U-shaped clearance on the head-side positioning structure, not only provides stable support for the workpiece head's machining and positioning but also effectively prevents the head and tail of the workpiece from being placed in reverse, improving workpiece positioning efficiency. Attached Figure Description

[0007] Figure 1 This is a schematic diagram of the structure of the workpiece to be processed; Figure 2 This is a schematic diagram of the overall structure of the clamp for fixed claw workpieces according to this application; Figure 3 A three-dimensional structural diagram of a clamp for fixing claw-type workpieces; Figure 4 A top view of the three-dimensional structure of a clamp for fixing claw-type workpieces; Figure 5 This is a schematic diagram of the head-tightening structure. Detailed Implementation

[0008] like Figures 2-5As shown, this application includes a fixture for fixing claw-type workpieces, comprising: a base 1, a positioning structure, and a clamping structure. The base 1 includes: a horizontally arranged base plate 11 and a vertically arranged connecting plate 12, the base plate 11 and the connecting plate 12 forming a U-shaped structure. The positioning structure and the clamping structure are mounted on the base plate 11. One end of the connecting plate 12 is connected to the base plate 11, and the other end is connected to a flange 8. The fixture is mounted on a CNC machine tool (not marked in the figure) via the flange 8.

[0009] The positioning structure includes: bottom positioning structure 2, tail side positioning structure 3 and head side positioning structure 4; the clamping structure includes: pressing structure 5, head clamping structure 6 and U-shaped opening top clamping structure 7.

[0010] The clamping structure 5 presses the workpiece to be processed onto the bottom positioning structure 2 from above. The head clamping structure 6, in conjunction with the tail side positioning structure 3, clamps the workpiece in the direction of the first through hole a3, ensuring stable operation of the processing of the first through hole a3, the second through hole a4, and the through groove a7. The head side positioning structure 4 and the U-shaped opening top clamping structure 7 work together to clamp the head of the workpiece, ensuring stable processing of the U-shaped opening a5 and the third through hole a6.

[0011] The bottom positioning structure 2 includes: a head bottom end face positioning block 21 and a tail bottom end face positioning block 22 of the same height. At least two head bottom end face positioning blocks 21 are provided, respectively positioned at the opening end of the U-shaped opening away from the tail of the workpiece and at the apex of the U-shaped opening; alternatively, multiple blocks can be evenly arranged along the bottom shape of the workpiece's U-shaped opening. The tail bottom end face positioning block 22 is positioned at the end of the workpiece's tail; for example... Figure 4 As shown, in this embodiment, the two head bottom end face positioning blocks 21 and the one tail bottom end face positioning block 22 are respectively based on cylindrical structures of the same size. The three positioning blocks form the three vertices of a triangle, ensuring stable support for the bottom of the workpiece.

[0012] The tail-side positioning structure 3 is located on the outer side of the tail, at the furthest point from the head; in this embodiment, the tail-side positioning structure 3 is implemented based on a cubic structure. To avoid affecting the machining of the through-groove a7 at the tail of the workpiece, the height of the tail-bottom end face positioning block 22 is set to be less than the inlet height of the through-groove at the tail of the workpiece placed on the bottom positioning structure 2, specifically as follows... Figure 2 and Figure 5 As shown.

[0013] The head side positioning structure 4 includes a rectangular positioning block 41, such as Figure 4As shown, a rectangular positioning block 41 is set on the side of the opening end of the U-shaped opening of the workpiece. A U-shaped clearance opening of the same size is opened on the rectangular positioning block 41 so that the U-shaped opening can be processed on the workpiece after positioning. The two opening ends of the U-shaped clearance opening are set opposite to the two opening ends of the U-shaped opening to be processed on the workpiece. This ensures that the workpiece head can be stably positioned in conjunction with the U-shaped opening top clamping structure 7 without hindering the processing.

[0014] The clamping structure 5 includes a clamping plate 51 and a clamping drive structure 52. The clamping plate 51 includes an integrally formed U-shaped head and a straight plate-shaped tail. The U-shaped head is adapted to the size of the U-shaped opening on the workpiece, and the tail is connected to the clamping drive structure 52. The clamping plate 51 clamps the workpiece from above around the U-shaped opening through the clamping drive structure 52. In this embodiment, the clamping drive structure 52 is based on a lever-type hydraulic cylinder in the prior art. The output end of the lever-type hydraulic cylinder is connected to the straight plate-shaped tail of the clamping plate 51, driving the U-shaped head of the clamping plate 51 to open and close in the vertical direction.

[0015] like Figure 3 , Figure 4 and Figure 5 As shown, the head clamping structure 6 includes: a clamping head 61 and a first clamping drive structure; the first clamping drive structure includes: a horizontal drive structure 62, a mounting plate 63, a rotating shaft 64, a clamping plate 65, and a connecting head 66.

[0016] The clamping head 61 is located on the outer side of the workpiece head at the furthest point from the workpiece tail. The clamping head 61 is positioned to avoid the machining location of the first through hole a3 on the workpiece. The clamping head 61 applies clamping force to the workpiece from the horizontal direction through the first clamping drive structure. The clamping head 61 of the head clamping structure 6 has an arc-shaped plate structure, ensuring that the clamping head 61 forms line contact with the flat sidewall of the workpiece head, ensuring a stable clamping force is applied to the workpiece.

[0017] The base plate 11 has a mounting groove 13 for tightening; the mounting plate 63 includes a horizontal plate and a vertical plate, which are arranged in an L-shape with the horizontal plate on top and the vertical plate on the bottom. The two mounting plates 63 are inserted into the inner cavity of the mounting groove 13 with the vertical plates facing each other. The horizontal plate has a threaded hole and is fixed to the upper end face of the base plate 11 by bolts.

[0018] A rotating shaft 64 is horizontally positioned between two mounting plates 63, perpendicular to the axis of the first through hole in the workpiece. A vertical plate is fixedly connected to each end of the rotating shaft 64. A clamping head 61 is positioned on the top of a clamping plate 65 facing the workpiece, and its bottom extends through the mounting groove 13 to below the base plate 11. The middle of the clamping plate 65 is movably fitted onto the rotating shaft 64. A horizontal drive structure 62 is positioned below the base plate 11, with its output end parallel to the axis of the first through hole in the workpiece. A connector 66 is mounted on the output end of the horizontal drive structure 62 and is horizontally positioned on the side of the end of the clamping plate 65.

[0019] The horizontal drive structure 62 is implemented based on a linear drive device, such as a pneumatic cylinder or a hydraulic cylinder. In this embodiment, it is implemented based on a hydraulic cylinder. Specifically, the horizontal drive structure 62 is implemented based on a single-acting cylinder, with the connector 66 connected to the output end of the single-acting cylinder. After the horizontal drive structure 62 is started, it drives the connector 66 to horizontally push the end of the clamping plate 65. The clamping plate 65 rotates about the rotating shaft 64, and the clamping head 61 at the top of the clamping plate 65 applies a horizontal thrust to the side wall of the workpiece head, cooperating with the tail side positioning structure 3 to clamp the workpiece. When the horizontal drive structure 62 is started in reverse, after the connector 66 is taken away from the bottom of the clamping plate 65, the clamping head 61 no longer applies pressure to the workpiece.

[0020] The U-shaped opening top clamping structure 7 includes a clamping connector 71 and a clamping drive structure 72. The clamping connector 71 is located on the outer side of the U-shaped arc segment of the workpiece. Under the action of the clamping drive structure 72, the clamping structure applies a horizontal clamping force to the U-shaped arc segment of the workpiece. The clamping drive structure 72 is based on a horizontally positioned single-acting cylinder.

[0021] To ensure a stable clamping of the arc-shaped tip of the U-shaped opening, such as Figure 4 As shown, in this embodiment, two clamping joints 71 are provided. The two open ends of the workpiece U-shaped opening are of equal length. The two rod-shaped clamping joints 71 are symmetrically arranged on the outside of the arc segment of the U-shaped opening of the workpiece with the perpendicular bisector of the line connecting the two open ends of the workpiece U-shaped opening as the axis of symmetry. The included angle α between the two clamping joints 71 is set to 60 degrees.

[0022] Using the technical solution of this utility model, two head bottom end face positioning blocks 21, one tail bottom end face positioning block 22, a rectangular positioning block 41 with a U-shaped clearance opening, and a tail side positioning structure 3 constitute a 6-point positioning system. After placing the workpiece to be processed on the top of the bottom positioning structure 2, the workpiece is pushed so that its side is pressed against the rectangular positioning block 41 and the tail side positioning structure 3 to ensure accurate positioning of the workpiece. The rectangular positioning block 41 with the U-shaped clearance opening can effectively prevent the workpiece from being inverted and improve positioning efficiency. After positioning, the hydraulic switch of the equipment is turned on, and the two clamping drive structures 72 drive the clamping joint 71 to move horizontally. The outer side of the U-shaped arc segment of the workpiece is pressed against the workpiece. The horizontal drive structure 62 drives the clamping head 61 to clamp the workpiece from the head, and the clamping drive structure 52 drives the clamping plate 51 to clamp the U-shaped processing part of the workpiece from above, completing the fixation. Then, the holes, grooves, and U-shaped contours on the workpiece are processed. After processing is completed, the hydraulic switch is turned off, and each clamping structure is reset with the oil cylinder, and the workpiece can be removed.

Claims

1. A jig for holding a workpiece of the type of a fixed jaw, characterized by comprising: It includes: Base, positioning structure and clamping structure; The positioning structure and the clamping structure are disposed on the base; The positioning structure includes: a bottom positioning structure, a tail side positioning structure, and a head side positioning structure; The bottom positioning structure includes: a head bottom end face positioning block and a tail bottom end face positioning block. At least two head bottom end face positioning blocks are provided, respectively located at the opening end of the U-shaped opening away from the tail of the workpiece and at the apex of the U-shaped opening. The tail bottom end face positioning block is located at the end of the tail of the workpiece. The tail side positioning structure is located on the outer side of the tail at the position furthest from the head; The head side positioning structure includes a rectangular positioning block, which is set on the side of the opening end of the U-shaped opening of the workpiece. A U-shaped clearance opening of the same size is opened on the rectangular positioning block, and the two opening ends of the U-shaped clearance opening are set opposite to the two opening ends of the U-shaped opening to be processed on the workpiece. The clamping structure includes: a pressing structure, a head clamping structure, and a U-shaped opening top clamping structure; The clamping structure includes a clamping plate and a clamping drive structure. The clamping plate includes an integrally formed U-shaped head and a straight plate-shaped tail. The U-shaped head is adapted to the size of the U-shaped opening on the workpiece, and the tail is connected to the clamping drive structure. The clamping plate clamps the workpiece from the top around the U-shaped opening of the workpiece through the clamping drive structure. The head clamping structure includes: a clamping head and a first clamping drive structure; the clamping head is located on the outer side of the workpiece head at the position furthest from the workpiece tail, and the clamping head is located away from the machining position of the first through hole on the workpiece; the clamping head applies clamping force to the workpiece from the horizontal direction through the first clamping drive structure. The U-shaped opening top clamping structure includes a clamping joint and a clamping drive structure. The clamping joint is located on the outside of the U-shaped opening arc segment of the workpiece, and the clamping structure applies a horizontal clamping force to the U-shaped opening arc segment of the workpiece under the action of the clamping drive structure.

2. The fixture according to claim 1, wherein: The base includes a horizontally arranged base plate and a vertically arranged connecting plate, the base plate and the connecting plate forming a U-shaped structure, and the positioning structure and the clamping structure are mounted on the base plate.

3. The fixture according to claim 2, wherein: The first clamping drive structure includes: a horizontal drive structure, a connector, a mounting plate, a clamping plate, and a rotating shaft; A mounting groove for tightening is provided on the base plate; The mounting plate includes a horizontal plate and a vertical plate, which are arranged in an L-shape with the horizontal plate on top and the vertical plate on the bottom; the two mounting plates are inserted into the inner cavity of the mounting groove for tightening with the vertical plates facing each other, and the horizontal plate is fixed on the base plate. The rotating shaft is horizontally positioned between two mounting plates in a direction perpendicular to the axis of the first through hole of the workpiece. A vertical plate is fixedly connected to each end of the rotating shaft. The top end of the clamping plate is provided with the clamping head facing the workpiece, and the bottom end extends through the mounting groove to the bottom plate. The middle part of the clamping plate is movably fitted onto the rotating shaft. The horizontal drive structure is located below the base plate, and the output end of the horizontal drive structure is parallel to the axis of the first through hole of the workpiece; the connector is installed on the output end of the horizontal drive structure; the connector is horizontally located on the side of the end of the clamping plate.

4. The fixture according to claim 1, wherein: The height of the tail bottom end positioning block is less than the inlet height of the workpiece tail through groove placed on the bottom positioning structure.

5. The fixture according to claim 1, wherein: The head bottom end face positioning block and the tail bottom end face positioning block are at the same height.

6. The fixture according to claim 1, wherein: The clamping head of the head clamping structure is an arc-shaped plate structure that forms line contact with the side wall of the workpiece.

7. The fixture according to claim 1, wherein: Two clamping joints are provided, and the two clamping joints are symmetrically arranged on the outside of the arc segment of the U-shaped opening of the workpiece with the perpendicular bisector of the two opening ends of the workpiece as the symmetrical reference. The included angle between the two clamping joints is 60 degrees.

8. The clamp for fixing claw-type workpieces according to claim 2, characterized in that: It also includes: a connecting flange, wherein one end of the connecting plate is connected to the base plate and the other end is connected to the flange.

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