A special-shaped workpiece clamping tool and a method for using the same

Abstract

The application relates to the technical field of tool clamps, in particular to a special-shaped workpiece clamping tool and a use method thereof. The special-shaped workpiece clamping tool comprises a base, a backing plate installed on the base, a first pin hole and a second pin hole arranged on the backing plate, a positioning pin installed in the first pin hole or the second pin hole, a pull rod and a pressing plate installed at the end of the pull rod. The use method of the special-shaped workpiece clamping tool is as follows: two positioning pins are installed in the first pin hole; four positioning holes on the special-shaped workpiece are aligned with the four first pin holes; the pull rod drives the pressing plate to press the special-shaped workpiece tightly; a hole is drilled at one end of the special-shaped workpiece; two positioning pins are installed in the second pin hole; the special-shaped workpiece is turned over, four positioning holes on the base are aligned with the four second pin holes; the pull rod drives the pressing plate to press the special-shaped workpiece tightly; a hole is drilled at the other end of the special-shaped workpiece through a drilling machine. The application solves the problem of axis deviation of the machined hole caused by turning over and improves the machining efficiency.

Description

Technical Field

[0001] This application relates to the field of tooling and fixture technology, and in particular to a clamping fixture for irregularly shaped workpieces and its method of use. Background Technology

[0002] The workpiece requires machining holes at both ends, with coaxiality between the holes. The bottom surface of the workpiece has been milled flat in the previous process, and the four small holes on the bottom surface have also been machined in the previous process. This process will use the already machined bottom surface and two of the four small holes for positioning, commonly known in the industry as "one-sided two-pin positioning." Since the holes to be machined on the workpiece are at both ends, when using a vertical machining center or drilling machine, the workpiece needs to be flipped and repositioned to machine these two holes separately from both ends. However, the axis of the hole to be machined is not on the plane of symmetry of the four holes. When flipping the workpiece, if the original two holes are still used for positioning, the axis of the hole to be machined will deviate from the machine tool spindle.

[0003] Since the position of the base angle iron is fixed when the tooling is initially installed, moving the spindle by changing the machine tool programming will reduce the coaxiality of the machined hole and also reduce efficiency. Summary of the Invention

[0004] This application aims to at least partially solve one of the aforementioned technical problems in the prior art. To this end, embodiments of this application provide a clamping fixture for irregularly shaped workpieces and a method for using it, which solves the problem of the axis of the machined hole deviating due to the flipping of the irregularly shaped workpiece. It eliminates the need to change the machine tool programming to move the spindle, thereby improving the coaxiality of the machined hole and also increasing processing efficiency.

[0005] A clamping fixture for irregularly shaped workpieces, the workpieces including a base, the base having four rectangularly distributed positioning holes, comprising: Base; A pad, which is detachably mounted on the base, is provided with four first pin holes and four second pin holes arranged in a rectangular pattern; When the irregularly shaped workpiece is mounted face-up on the pad, the four first pin holes correspond to the four positioning holes on the base. The positioning pins are installed in any two of the first pin holes that are diagonally distributed, and each positioning pin engages with the corresponding positioning hole. When the irregularly shaped workpiece is mounted face-down on the pad, the four second pin holes correspond to the four positioning holes on the base. The positioning pins are installed in any two of the second pin holes that are diagonally distributed, and each positioning pin engages with the corresponding positioning hole. The central axis of the irregularly shaped workpiece when it is mounted with the four first pin holes coincides with the central axis of the irregularly shaped workpiece when it is mounted with the four second pin holes. A tie rod, which is slidably engaged with the base and the pad; A pressure plate is installed at the end of the pull rod, and the pull rod moves to drive the pressure plate to press the irregularly shaped workpiece onto the pad.

[0006] In an optional or preferred embodiment, the base includes a horizontal plate and a vertical plate, the vertical plate being vertically fixed to the horizontal plate, the first pin hole and the second pin hole being formed on the vertical plate, and the pad being connected parallel to the vertical plate.

[0007] In an optional or preferred embodiment, the offset between the first pin hole and the second pin hole is the offset of the coaxiality when the irregular workpiece is rotated forward and backward.

[0008] In an optional or preferred embodiment, a drive component is further included, which is mounted on the upright plate, and the pull rod is connected to the power output end of the drive component.

[0009] In an optional or preferred embodiment, the pad is provided with a first through hole and a second through hole, and the upright plate is provided with a third through hole and a fourth through hole. After the pad is connected to the upright plate, the first through hole is aligned with the third through hole, and the second through hole is aligned with the fourth through hole. The pull rod passes through the first through hole and the third through hole to press the irregularly shaped workpiece forward on the pad, and the pull rod passes through the second through hole and the fourth through hole to press the irregularly shaped workpiece backward on the pad.

[0010] In an optional or preferred embodiment, the end cap is provided at the end of the pull rod, and the pressure plate is provided with an opening groove extending along the length direction of the pressure plate. The opening groove extends from the middle of the pressure plate to one side of the pressure plate and forms an opening on one side of the pressure plate. The pull rod passes through the opening groove, and the diameter of the end cap is larger than the diameter of the opening groove. The pull rod presses the pressure plate onto the irregular workpiece through the end cap.

[0011] In an optional or preferred embodiment, the positioning pin includes a pin seat and a pin shaft coaxially connected. The diameter of the pin shaft is smaller than the diameter of the pin seat. The upright plate is provided with four first holes arranged in a rectangular pattern and four second holes arranged in a rectangular pattern. The first holes are aligned with the first pin holes, and the second holes are aligned with the second pin holes. When the irregularly shaped workpiece is pressed against the pad in the forward direction, the pin seat of the positioning pin is assembled in the first holes and the first pin holes, and the pin shaft of the positioning pin is assembled in the positioning hole. When the irregularly shaped workpiece is pressed against the pad in the reverse direction, the pin seat of the positioning pin is assembled in the second holes and the second pin holes, and the pin shaft of the positioning pin is assembled in the positioning hole.

[0012] In an optional or preferred embodiment, the pad is detachably connected to the base.

[0013] In an optional or preferred embodiment, four first bolt holes are arranged in an array on the pad, and four second bolt holes are arranged in an array on the upright plate. The first bolt holes and the second bolt holes are aligned, and bolts are connected in the first bolt holes and the second bolt holes.

[0014] A method for using an irregularly shaped workpiece clamping fixture, for clamping an irregularly shaped workpiece using the aforementioned fixture, characterized by comprising the following steps: Install two locating pins in any two diagonally distributed first pin holes; Align the four positioning holes on the base of the irregular workpiece with the four first pin holes, so that the two positioning pins engage with the two positioning holes respectively. The pull rod drives the pressure plate, which presses the irregularly shaped workpiece firmly onto the base; Drill a hole at one end of the irregularly shaped workpiece using a drilling machine; After drilling is completed at one end of the irregular workpiece, the pull rod is released from the irregular workpiece, and the two positioning pins are removed. Install two locating pins in any two diagonally distributed second pin holes; After flipping the irregularly shaped workpiece, align the four positioning holes on the base with the four second pin holes, so that the two positioning pins engage with the two positioning holes respectively. The pull rod drives the pressure plate, which presses the irregularly shaped workpiece firmly onto the base; Drill a hole at the other end of the irregularly shaped workpiece using a drilling machine.

[0015] Based on the above technical solution, the embodiments of this application have at least the following beneficial effects: the offset between the first pin hole and the second pin hole is precisely set according to the coaxiality requirements of the irregular workpiece during forward and reverse rotation, and this offset is consistent with the coaxiality offset of the workpiece during forward and reverse rotation. Through this structural compensation, the geometric deviation caused by the rotation can be automatically eliminated after the workpiece is rotated, thereby ensuring that the machining axes of the holes at both ends of the workpiece remain strictly coaxial. This effectively ensures the coaxiality of the machined holes at both ends, solves the problem of the machined hole axis deviation caused by the rotation of irregular workpieces, and eliminates the need to move the spindle by changing the machine tool programming, thereby improving the coaxiality of the machined holes and also improving machining efficiency. Attached Figure Description

[0016] The present application will be further described below with reference to the accompanying drawings and embodiments; Figure 1 This is a schematic diagram of the structure of an irregular workpiece clamping fixture provided in one embodiment of this application when used for forward clamping of a workpiece; Figure 2 This is a schematic diagram of the structure of an irregular workpiece clamping fixture provided in one embodiment of this application when used for forward clamping of a workpiece; Figure 3 yes Figure 1 The front view of the embodiment shown; Figure 4 yes Figure 2 The front view of the embodiment shown; Figure 5 This is a schematic diagram of the positioning pin of the clamping fixture for irregularly shaped workpieces provided in an embodiment of this application; Figure 6 This is a schematic diagram of the structure of the irregular workpiece clamping fixture provided in one embodiment of the present application, which clamps the irregular workpiece in the forward direction; Figure 7 This is a schematic diagram of the structure of the irregular workpiece clamping fixture provided in one embodiment of the present application, which clamps the irregular workpiece in reverse. Figure 8 yes Figure 6 Exploded view of the embodiment shown.

[0017] Figure label: 100 - Irregularly shaped workpiece; 110 - Base; 111 - Positioning hole; 200 - Base; 210 - Horizontal plate; 220 - Vertical plate; 221 - First hole; 222 - Second hole; 223 - Fourth through hole; 224 - Second bolt hole; 300 - Pad; 301 - First rectangular distribution frame; 302 - Second rectangular distribution frame; 310 - First pin hole; 320 - Second pin hole; 330 - First through hole; 340 - Second through hole; 350 - First bolt hole; 350 - ; 400 - Positioning pin; 410 - Pin seat; 420 - Pin shaft; 500 - Tie rod; 510 - End cap; 600 - Pressure plate; 700 - Drive component. Detailed Implementation

[0018] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0019] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0020] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0021] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0022] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0023] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0024] The workpiece requires machining holes at both ends, with coaxiality between the holes. The bottom surface of the workpiece has been milled flat in the previous process, and the four small holes on the bottom surface have also been machined in the previous process. This process will use the already machined bottom surface and two of the four small holes for positioning, commonly known in the industry as "one-sided two-pin positioning." Since the holes to be machined on the workpiece are at both ends, when using a vertical machining center or drilling machine, the workpiece needs to be flipped and repositioned to machine these two holes separately from both ends. However, the axis of the hole to be machined is not on the plane of symmetry of the four holes. When flipping the workpiece, if the original two holes are still used for positioning, the axis of the hole to be machined will deviate from the machine tool spindle.

[0025] Since the position of the base angle iron is fixed when the tooling is initially installed, moving the spindle by changing the machine tool programming will reduce the coaxiality of the machined hole and also reduce efficiency.

[0026] Reference Figures 1 to 8 This invention relates to a clamping fixture for irregularly shaped workpieces and its method of use. The invention will be further described in detail below with reference to specific embodiments.

[0027] The irregular workpiece clamping fixture includes a base 200, a pad 300, locating pins 400, a tie rod 500, and a pressure plate 600. The base 200 serves as the basic support structure for the entire fixture and includes a horizontal plate 210 and a vertical plate 220, with the vertical plate 220 vertically fixed to the horizontal plate 210. The pad 300 is detachably mounted on the vertical plate 220 of the base 200. Four first bolt holes 350 are arranged in an array on the pad 300, and four second bolt holes 224 are arranged in an array on the vertical plate 220. By aligning the four first bolt holes 350 with the corresponding four second bolt holes 224 on the vertical plate 220 and fastening them with bolts, reliable fixation of the pad 300 to the base 200 is achieved.

[0028] The pad 300 has four rectangularly distributed first pin holes 310 and four rectangularly distributed second pin holes 320. Specifically, as shown... Figure 3 , 4 As shown, the first rectangular distribution frame 301 of the four first pin holes 310 and the second rectangular distribution frame 302 of the four second pin holes 320 have an offset in the horizontal direction.

[0029] The offset between the first pin hole 310 and the second pin hole 320 is precisely set according to the coaxiality requirements of the irregular workpiece 100 during forward and reverse rotation. This offset is consistent with the coaxiality offset of the irregular workpiece 100 during forward and reverse rotation. Through this structural compensation, the geometric deviation caused by the rotation can be automatically eliminated after the irregular workpiece 100 is rotated, thereby ensuring that the machining axes of the holes at both ends of the irregular workpiece 100 remain strictly coaxial. This effectively ensures the coaxiality of the machined holes at both ends, solving the problem of the machined hole axis deviation caused by the rotation of the irregular workpiece 100. It eliminates the need to change the machine tool programming to move the spindle, thereby improving the coaxiality of the machined holes and also increasing machining efficiency.

[0030] Reference Figure 5 The positioning pin 400 includes a pin seat 410 and a pin shaft 420 coaxially connected. The diameter of the pin shaft 420 is smaller than the diameter of the pin seat 410 to facilitate precise insertion into the positioning hole 111. The upright plate 220 is provided with four rectangularly distributed first holes 221 and four rectangularly distributed second holes 222. The first holes 221 are aligned with the first pin holes 310, and the second holes 222 are aligned with the second pin holes 320. When the irregularly shaped workpiece 100 is mounted upright on the pad 300, the four first pin holes 310 correspond to the four positioning holes 111 on the workpiece base 110. Two positioning pins 400 are installed in any two diagonally distributed first pin holes 310 and their corresponding first hole positions 221. At this time, the pin shaft 420 is inserted into the corresponding positioning hole 111, achieving precise positioning with "two pins on one side." When the irregularly shaped workpiece 100 is mounted in reverse on the pad 300, the four second pin holes 320 correspond to the four positioning holes 111 on the base 110. Two positioning pins 400 are installed in any two diagonally distributed second pin holes 320 and their corresponding second hole positions 222. The pin shaft 420 is also inserted into the positioning hole 111 to achieve precise positioning. This design ensures that the workpiece can be quickly and accurately aligned and installed in both upright and reverse mounting states, significantly improving positioning accuracy and consistency of repeatability.

[0031] The pull rod 500 slides in conjunction with the base 200 and the pad 300 to drive the pressure plate 600 to perform clamping and loosening actions. The pad 300 has a first through hole 330 and a second through hole 340, and the upright plate 220 has a third through hole and a fourth through hole 223. When the pad 300 is connected to the upright plate 220, the first through hole 330 aligns with the third through hole, and the second through hole 340 aligns with the fourth through hole 223. The pull rod 500 passes through the first through hole 330 and the third through hole to clamp the irregularly shaped workpiece 100 installed in the correct orientation; the pull rod 500 passes through the second through hole 340 and the fourth through hole 223 to clamp the irregularly shaped workpiece 100 installed in the reverse orientation.

[0032] The end of the pull rod 500 is provided with an end cap 510, and the pressure plate 600 has an opening groove extending along its length. This opening groove extends from the middle of the pressure plate 600 to one side and forms an opening. The pull rod 500 passes through the opening groove, and the diameter of the end cap 510 is larger than the width of the opening groove. Through the movement of the pull rod 500, the end cap 510 can press the pressure plate 600 onto the irregularly shaped workpiece 100, providing a uniform and stable clamping force, preventing the workpiece from shifting during processing, and ensuring processing accuracy. This structure allows the pressure plate 600 to be quickly installed and removed, facilitating workpiece clamping operations while maintaining clamping stability.

[0033] In some embodiments, the tooling further includes a drive component 700, which can be a pneumatic cylinder, a hydraulic cylinder, or an electric push rod, with its power output end connected to the pull rod 500. The movement of the drive component 700 enables automated movement of the pull rod 500, thereby completing the clamping or loosening of the workpiece, reducing manual operation, and improving the automation level and processing efficiency of the tooling.

[0034] This application also provides a method for using a clamping fixture for irregularly shaped workpieces, comprising the following steps: First, two positioning pins 400 are installed in any two diagonally distributed first pin holes 310 and corresponding first hole positions 221; the four positioning holes 111 on the base 110 of the irregularly shaped workpiece 100 are aligned with the four first pin holes 310, so that the pin shafts 420 of the two positioning pins 400 are respectively inserted into the two positioning holes 111, completing the positioning of the workpiece in the forward orientation; the driving component 700 is activated, and the pull rod 500 drives the pressure plate 600 to move, so that the pressure plate 600 stably presses the irregularly shaped workpiece 100 onto the pad 300; the irregularly shaped workpiece 100 is clamped by a drilling machine or a vertical machining center. Drill a hole at one end; after machining this end, the drive component 700 is released, the pull rod 500 drives the pressure plate 600 to release the workpiece, and the two positioning pins 400 are removed; then, the two positioning pins 400 are installed in any two diagonally distributed second pin holes 320 and corresponding second hole positions 222; the workpiece is flipped so that the four positioning holes 111 on the base 110 are aligned with the four second pin holes 320, and the pin shafts 420 of the two positioning pins 400 are inserted into the two positioning holes 111 respectively, completing the positioning of the workpiece in reverse installation; the drive component 700 is activated again, and the pull rod 500 drives the pressure plate 600 to press the workpiece; a hole is drilled at the other end of the workpiece using a drilling machine or vertical machining center. Since the offset between the first pin hole 310 and the second pin hole 320 is precisely calculated, the central axis of the machined hole after the workpiece is installed in both directions remains coincident, thereby ensuring high coaxiality of the holes at both ends, eliminating the need to adjust the machine tool spindle position, which improves machining accuracy and consistency, and also increases production efficiency.

[0035] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application.

Claims

1. A clamping fixture for irregularly shaped workpieces, used for clamping irregularly shaped workpieces, the irregularly shaped workpieces including a base, the base having four positioning holes arranged in a rectangular pattern, characterized in that, include: Base; A pad, which is detachably mounted on the base, is provided with four first pin holes and four second pin holes arranged in a rectangular pattern; When the irregularly shaped workpiece is mounted face-up on the pad, the four first pin holes correspond to the four positioning holes on the base. The positioning pins are installed in any two of the first pin holes that are diagonally distributed, and each positioning pin engages with the corresponding positioning hole. When the irregularly shaped workpiece is mounted face-down on the pad, the four second pin holes correspond to the four positioning holes on the base. The positioning pins are installed in any two of the second pin holes that are diagonally distributed, and each positioning pin engages with the corresponding positioning hole. The offset between the first pin holes and the second pin holes is the offset of the coaxiality when the irregularly shaped workpiece is mounted face-up. The central axis of the irregularly shaped workpiece when mounted with the four first pin holes coincides with the central axis of the irregularly shaped workpiece when mounted with the four second pin holes. A tie rod, which is slidably engaged with the base and the pad; A pressure plate is installed at the end of the pull rod, and the pull rod moves to drive the pressure plate to press the irregularly shaped workpiece onto the pad.

2. The clamping fixture for irregularly shaped workpieces according to claim 1, characterized in that: The base includes a horizontal plate and a vertical plate, the vertical plate being vertically fixed to the horizontal plate, and the pad being connected parallel to the vertical plate.

3. The clamping fixture for irregularly shaped workpieces according to claim 2, characterized in that: It also includes a drive component, which is mounted on the upright plate, and the pull rod is connected to the power output end of the drive component.

4. The clamping fixture for irregularly shaped workpieces according to claim 2, characterized in that: The pad is provided with a first through hole and a second through hole, and the upright plate is provided with a third through hole and a fourth through hole. After the pad is connected to the upright plate, the first through hole and the third through hole are aligned, and the second through hole and the fourth through hole are aligned. The pull rod passes through the first through hole and the third through hole to press the irregular workpiece forward on the pad, and the pull rod passes through the second through hole and the fourth through hole to press the irregular workpiece backward on the pad.

5. The clamping fixture for irregularly shaped workpieces according to claim 4, characterized in that: The end cap of the pull rod is provided, and the pressure plate is provided with an opening groove extending along the length direction of the pressure plate. The opening groove extends from the middle of the pressure plate to one side of the pressure plate and forms an opening on one side of the pressure plate. The pull rod passes through the opening groove. The diameter of the end cap is larger than the width of the opening groove. The pull rod presses the pressure plate onto the irregular workpiece through the end cap.

6. The clamping fixture for irregularly shaped workpieces according to claim 2, characterized in that: The positioning pin includes a pin seat and a pin shaft coaxially connected. The diameter of the pin shaft is smaller than the diameter of the pin seat. The upright plate has four first holes arranged in a rectangular pattern and four second holes arranged in a rectangular pattern. The first holes are aligned with the first pin holes, and the second holes are aligned with the second pin holes. When the irregularly shaped workpiece is pressed against the pad in the forward direction, the pin seat of the positioning pin is assembled in the first hole and the first pin hole, and the pin shaft of the positioning pin is assembled in the positioning hole. When the irregularly shaped workpiece is pressed against the pad in the reverse direction, the pin seat of the positioning pin is assembled in the second hole and the second pin hole, and the pin shaft of the positioning pin is assembled in the positioning hole.

7. The method of using the clamping fixture for irregularly shaped workpieces according to claim 2, characterized in that: The pad has four first bolt holes arranged in an array, and the upright plate has four second bolt holes arranged in an array. The first bolt holes and the second bolt holes are aligned, and bolts are connected in the first bolt holes and the second bolt holes.

8. A method of using a clamping fixture for irregularly shaped workpieces, used to clamp irregularly shaped workpieces using the clamping fixture for irregularly shaped workpieces as described in claim 1, characterized in that, Includes the following steps: Install two locating pins in any two diagonally distributed first pin holes; Align the four positioning holes on the base of the irregular workpiece with the four first pin holes, so that the two positioning pins engage with the two positioning holes respectively. The pull rod drives the pressure plate, which presses the irregularly shaped workpiece firmly onto the base; Drill a hole at one end of the irregularly shaped workpiece using a drilling machine; After drilling is completed at one end of the irregular workpiece, the pull rod is released from the irregular workpiece, and the two positioning pins are removed. Install two locating pins in any two diagonally distributed second pin holes; After flipping the irregularly shaped workpiece, align the four positioning holes on the base with the four second pin holes, so that the two positioning pins engage with the two positioning holes respectively. The pull rod drives the pressure plate, which presses the irregularly shaped workpiece firmly onto the base; Drill a hole at the other end of the irregularly shaped workpiece using a drilling machine.

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