A dodecahedron head bolt product head drilling clamping tool and method

Abstract

The application relates to the technical field of bolt processing, in particular to a clamping tool and method for drilling the head of a twelve-angle head bolt product. The clamping tool comprises a bottom plate, a twelve-angle support installed on the top surface of the bottom plate and a supporting table. A sliding rail is installed on the top surface of the bottom plate, and a sliding groove is formed in the bottom surface of the supporting table. The sliding rail and the sliding groove are in sliding fit, so that the supporting table slides left and right on the top surface of the bottom plate. A plurality of twelve-angle grooves are arranged on the top of the twelve-angle support, and the twelve-angle grooves are arranged in sequence and at intervals from left to right. A push rod seat is installed on the supporting table. A plurality of stepped through holes are formed in the push rod seat, and one stepped through hole is arranged corresponding to each twelve-angle groove. A push rod is slidably inserted into the stepped through hole, and an elastic clamp sleeve is inserted into the front end of the central hole of the push rod. A spring is sleeved on the push rod, and the rear end of the spring abuts against the stepped surface of the stepped through hole. The spring is used for forming an axial forward thrust on the push rod.

Description

Technical Field

[0001] This invention relates to the field of bolt processing technology, and in particular to a clamping fixture and method for drilling holes in the head of a twelve-corner head bolt. Background Technology

[0002] Bolts are a common type of fastener in the mechanical field. They consist of a head and a shank (a cylinder with external threads). They require a nut to fasten two parts with through holes; this type of connection is called a bolted connection. Since the two parts can be separated by unscrewing the nut, a bolted connection is a detachable connection.

[0003] Dodecagonal head bolts are also a very common type of bolt. In dodecagonal head bolts, it is often necessary to drill a hole in the head to meet certain special purposes, such as a fuse hole.

[0004] When drilling holes in bolt heads, a clamp is required to hold the bolt. In the prior art, patent application CN107649902A discloses a dodecagonal bolt head drilling clamp, in which the dodecagonal hole is formed by combining one half of the hole on the pressure block and the other half of the hole on the base. When the L-shaped pressure block rotates along the corner, it causes the half of the hole on the pressure block to be tightened or loosened.

[0005] However, the fixtures in the prior art have the following problems: the fixture jig plate has only one clamping station, and can only clamp one bolt to be processed at a time, which seriously affects the processing efficiency and is not conducive to the batch drilling of bolts. Summary of the Invention

[0006] The main objective of this invention is to provide a clamping fixture and method for drilling holes in the head of a twelve-corner head bolt, in order to solve the aforementioned technical problems.

[0007] To achieve the above objectives, this invention provides a clamping fixture for drilling holes in the head of a dodecagonal head bolt, comprising a base plate, a dodecagonal support mounted on the top surface of the base plate, and a support platform; a slide rail is mounted on the top surface of the base plate, and a sliding groove is formed on the bottom surface of the support platform; the slide rail and the sliding groove are slidably engaged, allowing the support platform to slide left and right on the top surface of the base plate; multiple dodecagonal slots are provided on the top of the dodecagonal support, spaced apart from left to right; a push rod seat is mounted on the support platform; multiple stepped through holes are formed on the push rod seat, with each dodecagonal slot corresponding to one stepped through hole; a push rod is slidably inserted into the stepped through hole, and an elastic sleeve is inserted at the front end of the center hole of the push rod; a spring is sleeved on the push rod, and the rear end of the spring abuts against the stepped surface of the stepped through hole; the spring is used to generate a forward axial thrust on the push rod.

[0008] Preferably, the push rod includes a main rod body and an outer cylinder body integrally formed on the main rod body; an annular groove with a closed front end and an open rear end is formed between the outer cylinder body and the main rod body; the spring is sleeved on the main rod body, and the front end of the spring is installed in the annular groove.

[0009] Preferably, a limiting rod is provided on the outer circumferential surface of the outer cylinder; a pull ring is provided at the rear end of the main rod; multiple protrusions are provided on the top surface of the push rod seat, and a limiting stop strip is rotatably installed on the protrusions; a U-shaped groove is provided at the top of the push rod seat, and the U-shaped opening of the U-shaped groove faces the front of the clamp; when the push rod is pulled backward, the limiting rod enters the U-shaped groove, and after the limiting stop strip is rotated to flatten it, the limiting stop strip blocks the front side of the limiting rod to form a limit.

[0010] Preferably, when the limiting bar is rotated and laid flat, the front side of the limiting bar simultaneously abuts against the back of two adjacent protrusions, and the long side of the limiting bar abuts against the top surface of the push rod seat.

[0011] Preferably, a mounting hole is provided on the protrusion, and a plug shaft is provided on the front side of the limiting strip, the plug shaft being inserted into the mounting hole of the protrusion.

[0012] Preferably, a strip block is integrally formed on the top of the dodecagonal support, the strip block sealing the front end of each dodecagonal slot; multiple limiting screws are screwed onto the strip block, one limiting screw is provided for each dodecagonal slot, and the screw of the limiting screw extends into the dodecagonal slot; a locking nut is screwed onto the limiting screw, and when the locking nut is locked, the locking nut is close to the front side of the dodecagonal support.

[0013] Preferably, a right blocking block is integrally formed at the right end of the slide rail to block and limit the right end face of the support platform; a left blocking block is installed at the left end of the slide rail; the left blocking block is fastened to the base plate by screws, and the left blocking block is used to block and limit the left end face of the support platform; the slide rail is a slide rail with a dovetail-shaped cross-section; the slide groove is a slide groove with a dovetail-shaped cross-section.

[0014] Preferably, when the support platform moves to the right along the slide rail to its limit position, the support platform and the dodecagonal support are completely misaligned in the front-to-back direction; when the support platform moves to the left along the slide rail to its limit position, the support platform and the dodecagonal support are aligned in the front-to-back direction.

[0015] Preferably, two insertion posts are provided on the bottom surface of the push rod seat; two insertion holes corresponding to the positions of the insertion posts are provided on the support platform; the insertion posts are inserted into the insertion holes, and tightening screws are screwed on both sides of the support platform, the tightening screws being used to tighten against the outer cylindrical surface of the insertion posts.

[0016] Secondly, the present invention also proposes a method for drilling holes in the head of a twelve-head bolt product, using the above-mentioned clamping fixture, including the following steps: S1. Install the clamping fixture on the worktable of the CNC drilling machine; S2. Push the support platform to move to the right along the slide rail, so that the support platform and the dodecagonal support are misaligned in the front-to-back direction, and remove the elastic sleeve. S3. Insert the shank of the twelve-head bolt product to be processed into the elastic sleeve, and then insert the elastic sleeve with the twelve-head bolt product into the push rod. S4. After all push rods are equipped with the twelve-corner bolts to be processed, push the support platform to move to the left along the slide rail so that the support platform and the twelve-corner support are aligned with each other in the front-back direction. S5. Under the action of the spring, the push rod is pushed forward, so that the head of the twelve-corner bolt product to be processed is pressed into the twelve-corner groove of the twelve-corner support; S6. Start the drilling machine and drill holes in the heads of the twelve-head bolts on the clamping fixture in sequence. S7. After drilling all bolts, pull each push rod backward to disengage the head of the twelve-corner bolt from the twelve-corner slot, and push the support platform to move to the right along the slide rail to the limit position, so that the processed bolt can be removed.

[0017] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows: (1) By using the clamping fixture provided by the present invention, multiple twelve-head bolt products to be processed can be clamped at one time, which is conducive to improving processing efficiency.

[0018] (2) In this invention, by sleeved with a spring on the push rod, the spring is used to generate a forward axial thrust on the push rod, so that the head of the twelve-corner bolt product installed on the push rod can be pushed into the twelve-corner groove of the twelve-corner support, so as to achieve precise positioning and ensure that the bolt product does not shift during the drilling process, which is beneficial to improving the quality and efficiency of drilling.

[0019] (3) The clamping fixture provided by the present invention is simple and convenient to clamp, which is conducive to improving the clamping efficiency of twelve-corner head bolt products.

[0020] (4) In this invention, when the push rod is pulled backward and the limiting rod can enter the U-shaped groove, after the limiting bar is rotated and flattened, the limiting bar blocks the front side of the limiting rod to form a limit. At this time, the axial position of the push rod can be restricted. When the support platform is slid left and right, interference between the twelve-corner bolt product installed on the push rod and the twelve-corner support can be avoided. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0022] Figure 1 This is a three-dimensional structural diagram of the clamping fixture provided by the present invention.

[0023] Figure 2 This is a front view of the clamping fixture provided by the present invention.

[0024] Figure 3 This is a top view of the clamping fixture provided by the present invention.

[0025] Figure 4 This is a left view of the clamping fixture provided by the present invention.

[0026] Figure 5 This is the left-hand view of the support platform.

[0027] Figure 6 for Figure 5 Sectional view of AA.

[0028] Figure 7 This is a top view of the push rod.

[0029] Figure 8 for Figure 7 BB section view.

[0030] Figure 9 This is the front view of the push rod holder.

[0031] Figure 10 This is a left view of the push rod holder.

[0032] Figure 11 for Figure 9 CC section view.

[0033] Figure 12 This is the main view of the limit stop bar.

[0034] Figure 13 This is the left view of the limit stop bar.

[0035] Figure 14 This is the front view of the elastic jacket.

[0036] Figure 15 This is the right view of the elastic sleeve.

[0037] Figure 16 for Figure 14 DD section view.

[0038] The following are the reference numerals: 1. Base plate; 1a. Mounting groove; 2. Dodecagonal support; 2a. Dodecagonal groove; 2b. Strip block; 3. Support platform; 3a. Slide groove; 3b. Insertion hole; 4. Slide rail; 4a. Right blocking block; 4b. Left blocking block; 5. Push rod seat; 5a. Stepped through hole; 5b. Protrusion; 5c. U-shaped groove; 6. Push rod; 6a. Main rod body; 6b. Outer cylinder body; 6c. Annular groove; 7. Elastic sleeve; 8. Spring; 9. Limiting stop bar; 9a. Insertion shaft; 10. Pull ring; 11. Limiting screw; 12. Locking nut; 13. Tightening screw. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0040] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0041] Combination Figures 1 to 16 As shown, this embodiment provides a clamping fixture for drilling holes in the head of a dodecagonal head bolt, including a base plate 1, a dodecagonal support 2 mounted on the top surface of the base plate 1, and a support platform 3. Specifically, the dodecagonal support 2 is fastened to the top surface of the base plate 1 with screws. A slide rail 4 is installed on the top surface of the base plate 1, and a sliding groove 3a is formed on the bottom surface of the support platform 3. The slide rail 4 and the sliding groove 3a are slidably engaged, and the bottom surface of the support platform 3 slides relative to the top surface of the base plate 1, so that the support platform 3 can slide left and right on the top surface of the base plate 1. An installation groove 1a is provided on the base plate 1.

[0042] Multiple dodecagonal slots 2a are provided on the top of the dodecagonal support 2, and the multiple dodecagonal slots 2a are arranged alternately from left to right; a push rod seat 5 is installed on the support platform 3; multiple stepped through holes 5a are opened on the push rod seat 5, and each dodecagonal slot 2a is provided with a corresponding stepped through hole 5a.

[0043] A push rod 6 is slidably inserted into the stepped through hole 5a. The push rod 6 can slide back and forth. An elastic sleeve 7 is inserted into the front end of the central hole of the push rod 6.

[0044] A spring 8 is fitted onto the push rod 6, and the rear end of the spring 8 abuts against the stepped surface of the stepped through hole 5a; the spring 8 is used to generate a forward axial thrust on the push rod 6.

[0045] Secondly, this embodiment also provides a method for drilling holes in the head of a twelve-head bolt product, using the above-mentioned clamping fixture, including the following steps: S1. Install the clamping fixture on the worktable of the CNC drilling machine. Specifically, the clamping fixture is installed on the worktable of the CNC drilling machine by bolt fixing using the mounting groove 1a of the base plate 1.

[0046] S2. Push the support platform 3 to the right along the slide rail 4, so that the support platform 3 and the dodecagonal support 2 are misaligned in the front-back direction, and remove the elastic sleeve 7.

[0047] S3. Insert the shank of the twelve-head bolt product to be processed into the elastic sleeve 7, and then install the elastic sleeve 7 containing the twelve-head bolt product into the push rod 6.

[0048] S4. After all push rods 6 are equipped with dodecagonal head bolts to be processed, push the support platform 3 to move to the left along the slide rail 4 so that the support platform 3 and the dodecagonal support 2 are aligned with each other in the front-back direction.

[0049] S5. Under the action of spring 8, push rod 6 moves forward, so that the head of the dodecagonal head bolt product to be processed is pressed into the dodecagonal groove 2a of the dodecagonal support 2.

[0050] S6. Start the drilling machine and drill holes in the heads of the twelve-head bolts on the clamping fixture in sequence. S7. After all bolt products have been drilled, pull each push rod 6 backward to make the head of the twelve-corner bolt product exit from the twelve-corner slot 2a, push the support platform 3 to move to the right along the slide rail 4 to the limit position, and the processed bolt product can be removed.

[0051] Combination Figure 8As shown, the push rod 6 includes a main rod body 6a and an outer cylinder 6b integrally formed on the main rod body 6a; an annular groove 6c with a closed front end and an open rear end is formed between the outer cylinder 6b and the main rod body 6a; the spring 8 is sleeved on the main rod body 6a, and the front end of the spring 8 is installed in the annular groove 6c. The outer circumferential surface of the outer cylinder 6b slides in fit with the larger diameter section of the stepped through hole 5a. The purpose of providing the annular groove 6c is to facilitate the installation of the spring 8.

[0052] Combination Figure 1 As shown, a limiting rod 6d is provided on the outer circumferential surface of the outer cylinder 6b; a pull ring 10 is provided at the rear end of the main rod 6a; multiple protrusions 5b are provided on the top surface of the push rod seat 5, and a limiting stop strip 9 is rotatably installed on the protrusions 5b; a U-shaped groove 5c is formed at the top of the push rod seat 5, extending downwards from the top surface of the push rod seat 5 into the stepped through hole 5a, with the U-shaped opening of the U-shaped groove 5c facing the front of the clamp. When the push rod 6 is pulled backwards, overcoming the elastic force of the spring 8, the limiting rod 6d can enter the U-shaped groove 5c, according to... Figure 1 After the limiting bar 9 is rotated to a flat position in the direction indicated by the middle arrow A, the limiting bar 9 blocks the front side of the limiting rod 6d to form a limit.

[0053] Combination Figure 1 , Figure 9 and Figure 12 As shown, in this embodiment, each U-shaped groove 5c is provided with two protrusions 5b, and a mounting hole is provided on the protrusion 5b. A plug shaft 9a is provided on the front side of the limiting bar 9, and the plug shaft 9a is inserted into the mounting hole of the protrusion 5b. When the limiting bar 9 is in accordance with... Figure 1 After being rotated and flattened in the direction indicated by the middle arrow A, the front side of the limiting stop bar 9 simultaneously abuts against the back of two adjacent protrusions 5b, and the long side B of the limiting stop bar 9 abuts against the top surface of the push rod seat 5.

[0054] By adopting the above structure, in step S2, before pushing the support platform 3 to the right, the rod 6 is first pushed backward to overcome the elastic force of the spring 8, causing the rod 6 to move backward, and the limiting rod 6d enters the U-shaped groove 5c. At this time, according to... Figure 1 Rotate the limiting stop bar 9 in the direction indicated by the middle arrow A until it is flattened, until the long side B of the limiting stop bar 9 abuts against the top surface of the push rod seat 5. At this time, the limiting stop bar 9 blocks the front side of the limiting rod 6d, thereby limiting the axial position of the push rod 6. In steps S3 and S4, the limiting stop bar 9 is always kept blocking the front side of the limiting rod 6d.

[0055] Since the limiting bar 9 blocks the front side of the limiting rod 6d to form a limit, when the push rod 6 is equipped with the dodecagonal head bolt product, interference between the head of the dodecagonal head bolt product and the dodecagonal support 2 can be avoided during the movement of the support platform 3.

[0056] In step S5, after the support platform 3 and the dodecagonal support 2 are aligned with each other in the front-rear direction, along the... Figure 1 Rotate the limiting stop bar 9 in the opposite direction of the middle arrow A to release the limit. At this time, under the action of the spring 8, push the push rod 6 forward, so that the head of the twelve-corner bolt product to be processed is pressed into the twelve-corner groove 2a of the twelve-corner support 2. The twelve-corner groove 2a can not only support the head of the product, but also limit the angular direction of the head of the product, and prevent the bolt product from rotating around its own axis during the drilling process.

[0057] In step S7, each push rod 6 is pulled backward, causing the head of the dodecagonal head bolt to exit from the dodecagonal slot 2a, and the limiting rod 6d enters the U-shaped groove 5c, according to... Figure 1 Rotate the limiting stop bar 9 in the direction indicated by the middle arrow A to make it flat, so that the limiting stop bar 9 blocks the front side of the limiting rod 6d to form a limit, thereby restricting the axial position of the push rod 6. Then push the support platform 3 to move to the right along the slide rail 4 to the limit position. At this time, the push rod seat 5 and the dodecagonal support 2 are also misaligned, making it convenient to remove the processed bolt product.

[0058] Combination Figure 1 As shown, a strip block 2b is integrally formed on the top of the dodecagonal support 2, which seals the front end of each dodecagonal slot 2a. Multiple limiting screws 11 are screwed onto the strip block 2b, with one limiting screw 11 corresponding to each dodecagonal slot 2a, and the screw shank of the limiting screw 11 extends into the dodecagonal slot 2a. A locking nut 12 is screwed onto the limiting screw 11, and when the locking nut 12 is tightened, it abuts against the front side of the dodecagonal support 2. By using the limiting screws 11, the head of the dodecagonal head bolt is limited, i.e., the push rod 6 is pushed forward, causing the head of the dodecagonal head bolt to be processed to be pressed into the dodecagonal slot 2a of the dodecagonal support 2. When the bolt head abuts against the rear end face of the limiting screw 11, the axial position of the bolt is limited. The axial position of the bolt can be adjusted by adjusting the length of the limiting screw 11 extending into the dodecagonal slot 2a. Once the limit screw 11 is adjusted to the correct position, the limit screw 11 can be locked by tightening the locking nut 12.

[0059] Combination Figure 1As shown, a right blocking block 4a is integrally formed at the right end of the slide rail 4, which is used to block and limit the right end face of the support platform 3; a left blocking block 4b is installed at the left end of the slide rail 4; the left blocking block 4b is fastened to the base plate 1 by screws, and the left blocking block 4b is used to block and limit the left end face of the support platform 3; the slide rail 4 is a slide rail with a dovetail-shaped cross-section; the slide groove 3a is a slide groove with a dovetail-shaped cross-section. When the support platform 3 moves to the right along the slide rail 4 to its limit position (the support platform 3 abuts against the right blocking block 4a), the support platform 3 and the dodecagonal support 2 are completely misaligned in the front-back direction; when the support platform 3 moves to the left along the slide rail 4 to its limit position (the support platform 3 abuts against the left blocking block 4b), the support platform 3 and the dodecagonal support 2 are aligned in the front-back direction.

[0060] Combination Figure 1 , Figure 9 and Figure 10 As shown, two insertion posts 5d are provided on the bottom surface of the push rod seat 5; two insertion holes 3b corresponding to the positions of the insertion posts 5d are provided on the support platform 3; the insertion posts 5d are inserted into the insertion holes 3b, and tightening screws 13 are screwed onto both sides of the support platform 3, the tightening screws 13 being used to tighten the outer cylindrical surface of the insertion posts 5d. By adopting the structure of the insertion posts 5d cooperating with the insertion holes 3b, it is easy to adjust the height of the push rod seat 5 so that the axis of the push rod 6 coincides with the axis of the dodecagonal groove 2a. After the height of the push rod seat 5 is adjusted to the correct position, tightening the tightening screws 13 will tighten the insertion posts 5d.

[0061] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A chucking tool for drilling a head of a dodecahedron head bolt product, characterized by, Includes a base plate (1), a dodecagonal support (2) mounted on the top surface of the base plate (1), and a support platform (3); A slide rail (4) is installed on the top surface of the base plate (1), and a slide groove (3a) is provided on the bottom surface of the support platform (3); the slide rail (4) and the slide groove (3a) are slidably engaged so that the support platform (3) can slide left and right on the top surface of the base plate (1); Multiple dodecagonal slots (2a) are provided on the top of the dodecagonal support (2), and the multiple dodecagonal slots (2a) are arranged alternately from left to right; A push rod seat (5) is installed on the support platform (3); multiple stepped through holes (5a) are opened on the push rod seat (5), and each dodecagonal slot (2a) is provided with a stepped through hole (5a). A push rod (6) is slidably inserted into the stepped through hole (5a), and an elastic sleeve (7) is inserted into the front end of the center hole of the push rod (6). A spring (8) is fitted on the push rod (6), and the rear end of the spring (8) abuts against the stepped surface of the stepped through hole (5a); the spring (8) is used to generate a forward axial thrust on the push rod (6).

2. The clamping fixture according to claim 1, characterized in that, The push rod (6) includes a main rod body (6a) and an outer cylinder body (6b) integrally formed on the main rod body (6a). An annular groove (6c) with a closed front end and an open rear end is formed between the outer cylinder (6b) and the main rod (6a). The spring (8) is sleeved on the main rod (6a), and the front end of the spring (8) is installed in the annular groove (6c).

3. The clamping fixture according to claim 2, characterized in that, A limit rod (6d) is provided on the outer circumferential surface of the outer cylinder (6b); a pull ring (10) is provided at the rear end of the main rod (6a). Multiple protrusions (5b) are provided on the top surface of the push rod seat (5), and limit stops (9) are rotatably installed on the protrusions (5b); A U-shaped groove (5c) is provided on the top of the push rod seat (5), and the U-shaped opening of the U-shaped groove (5c) faces the front of the clamp; When the push rod (6) is pulled backward, the limiting rod (6d) enters the U-shaped groove (5c). After the limiting stop bar (9) is rotated and laid flat, the limiting stop bar (9) blocks the front side of the limiting rod (6d) to form a limit.

4. The clamping fixture according to claim 3, characterized in that, When the limiting bar (9) is rotated and laid flat, the front side of the limiting bar (9) simultaneously abuts against the back of two adjacent protrusions (5b), and the long side of the limiting bar (9) abuts against the top surface of the push rod seat (5).

5. The clamping fixture according to claim 3, characterized in that, A mounting hole is provided on the protrusion (5b), and a plug shaft (9a) is provided on the front side of the limiting stop bar (9), and the plug shaft (9a) is inserted into the mounting hole of the protrusion (5b).

6. The clamping fixture according to claim 1, characterized in that, A strip block (2b) is integrally formed on the top of the dodecagonal support (2), and the strip block (2b) seals the front end of each dodecagonal groove (2a); multiple limit screws (11) are screwed on the strip block (2b), and each dodecagonal groove (2a) is provided with a limit screw (11), and the screw of the limit screw (11) extends into the dodecagonal groove (2a); a locking nut (12) is screwed on the limit screw (11), and when the locking nut (12) is locked, the locking nut (12) is close to the front side of the dodecagonal support (2).

7. The clamping fixture according to claim 1, characterized in that, A right blocking block (4a) is integrally formed at the right end of the slide rail (4) to form a blocking limit on the right end face of the support platform (3); A left blocking block (4b) is installed at the left end of the slide rail (4); the left blocking block (4b) is fastened to the base plate (1) by screws, and the left blocking block (4b) is used to block and limit the left end face of the support platform (3); The slide rail (4) is a slide rail with a dovetail-shaped cross-section; the slide groove (3a) is a slide groove with a dovetail-shaped cross-section.

8. The clamping fixture according to claim 5, characterized in that, When the support platform (3) moves to the right along the slide rail (4) to the limit position, the support platform (3) and the dodecagonal support (2) are completely misaligned in the front-back direction; When the support platform (3) moves to the left along the slide rail (4) to the limit position, the support platform (3) and the dodecagonal support (2) are aligned with each other in the front-back direction.

9. The clamping fixture according to claim 1, characterized in that, Two plug-in pins (5d) are provided on the bottom surface of the push rod seat (5); two plug-in holes (3b) corresponding to the positions of the plug-in pins (5d) are provided on the support platform (3); The plug (5d) is inserted into the plug hole (3b), and tightening screws (13) are screwed on both sides of the support platform (3). The tightening screws (13) are used to tighten the plug (5d) on the outer cylindrical surface.

10. A method for drilling holes in the head of a twelve-point head bolt, characterized in that, The clamping fixture according to any one of claims 1 to 9 comprises the following steps: S1. Install the clamping fixture on the worktable of the CNC drilling machine; S2. Push the support platform (3) to move to the right along the slide rail (4) so ​​that the support platform (3) and the dodecagonal support (2) are misaligned in the front-back direction, and remove the elastic sleeve (7); S3. Insert the shank of the twelve-head bolt product to be processed into the elastic sleeve (7), and then install the elastic sleeve (7) with the twelve-head bolt product into the push rod (6). S4. After all push rods (6) are equipped with the dodecagonal head bolts to be processed, push the support platform (3) to move to the left along the slide rail (4) so ​​that the support platform (3) and the dodecagonal support (2) are aligned with each other in the front-back direction. S5. Under the action of the spring (8), the push rod (6) is pushed forward, so that the head of the dodecagonal head bolt product to be processed is pressed into the dodecagonal groove (2a) of the dodecagonal support (2); S6. Start the drilling machine and drill holes in the heads of the twelve-head bolts on the clamping fixture in sequence. S7. After all bolt products have been drilled, pull each push rod (6) backward to make the head of the twelve-corner bolt product exit from the twelve-corner groove (2a) position, push the support platform (3) along the slide rail (4) to the right to the limit position, and the processed bolt product can be removed.

Images