Centering chuck for machining three-pin holder

Abstract

The utility model relates to the technical field of centering chuck, more particularly to a kind of centering chuck for three-pin frame machining.For the convenience of clamping tripod center body, the following scheme is adopted: including three-jaw centering chuck, detachably connected with clamping column on the three clamping claws of three-jaw centering chuck, clamping column protrudes from clamping claw in the central direction of three-jaw centering chuck, the inner end of three clamping columns is located on a virtual circle, the axis of three clamping columns intersects and the intersection point is located on the virtual center.The size of clamping column is relatively small compared with clamping claw, usually the diameter of clamping column can be 1-5cm, especially suitable for abutting the intersection point of first curve and second curve of three-pin frame connecting part and other specific positions, to ensure that three clamping columns are synchronously attached to workpiece outer wall, and the clamping stability is significantly improved.The scheme of processing hole replaces the scheme of replacing grinding tool, to save cost.If larger three-pin frame needs to be processed, the diameter of hole and the diameter of clamping column can be increased.

Description

Technical Field

[0001] This utility model relates to the field of centering chuck technology, and more specifically to a centering chuck for machining three-pin holders. Background Technology

[0002] The jaws of three-jaw centering chucks are mostly universal type, directly contacting the outer wall of the three-pin holder. Due to differences in the dimensions of the central body and universal joints of different three-pin holder models, larger universal joints result in smaller distances between adjacent universal joints. The universal jaws are wider, leading to situations where adjacent universal joints obstruct the jaws, preventing them from reaching the central body of the three-pin holder. Custom machining of the jaws to change their dimensions requires changing the machining mold, which is costly.

[0003] Secondly, existing chucks lack a suitable support design for three-pin holder structures with height differences. Some three-pin holders have a structural feature where the bottom of the journal is higher than the bottom of the body. Traditional chucks only provide single-point support on the surface of the upper plate, resulting in a small number of support points and a short extension distance, which leads to unstable workpiece placement. Utility Model Content

[0004] This utility model provides a centering chuck for machining a three-pin frame, the purpose of which is to facilitate clamping the center body of the three-pin frame over the universal joint.

[0005] The above objectives are achieved through the following technical solutions: A centering chuck for machining a three-jaw centering chuck includes a three-jaw centering chuck, with detachable chuck pins connected to the three jaws of the three-jaw centering chuck. The chuck pins protrude from the jaws in the center direction of the three-jaw centering chuck, and the inner ends of the three chuck pins are located on a virtual circle. The axes of the three chuck pins intersect and the intersection point is located at the center of the virtual circle.

[0006] The claw has a first through hole, into which the pin can be inserted. The claw also has a second through hole that is longitudinal and communicates with the first through hole. Inserting the pin into the second through hole and passing through the third through hole can fix the relative position of the pin and the claw.

[0007] The locking post is provided with a radially arrayed array of third through holes. When the locking post is moved radially, the second through hole can communicate with any of the third through holes in the longitudinal direction.

[0008] The first through holes are arranged in a longitudinal array on the jaws, and the second through holes are connected to all the first through holes.

[0009] The top of the insert can magnetically attach to the top of the claw.

[0010] The diameter of the central opening at the top of the claw-centering chuck is greater than the maximum diameter of the three-pin bracket excluding the universal joint portion.

[0011] It also includes a boss, which is screwed into the top of the three-jaw centering chuck by means of a threaded connection, so that the boss is located in the center circle of the top of the three-jaw centering chuck.

[0012] When the universal joint of the three-pin carrier is at its lowest point, the boss lifts the center of the three-pin carrier above the top surface of the three-jaw centering chuck, and the universal joint of the three-pin carrier is placed on the top surface of the three-jaw centering chuck. When the lowest position of the universal joint of the three-pin frame is higher than the lowest point of the main body structure at the center of the three-pin frame, remove the boss and place the main body structure of the three-pin frame into the central round opening at the top of the three-jaw centering chuck to achieve a sunken placement, with the universal joint of the three-pin frame placed on the upper surface of the upper plate.

[0013] The centering chuck is a manual three-jaw centering chuck.

[0014] The transmission principle of a manual three-jaw centering chuck is based on the transmission between bevel gears and a screw spool.

[0015] The beneficial effects of this utility model of a centering chuck for machining three-pin supports are as follows: By setting longitudinally arrayed first through holes on the jaws, the locking pins can be inserted into any of the first through holes to achieve a clearance fit. Combined with the conductive design of the radially arrayed third through holes and the longitudinal second through holes, the insertion pins can quickly fix the relative position of the locking pins and jaws. This multi-position adjustment structure allows the locking pins to flexibly adjust the contact point according to the outer wall contour of the three-pin holder. The locking pins are relatively small compared to the jaws, typically with a diameter of 1-5cm. This is especially suitable for specific positions such as the intersection of the first and second curves of the three-pin holder connection, ensuring that the three locking pins synchronously conform to the outer wall of the workpiece, significantly improving clamping stability. The solution of machining holes replaces the mold replacement solution, saving costs. If a larger three-pin holder needs to be machined, the diameter of the holes and the diameter of the locking pins can be increased.

[0016] The diameter of the central opening at the top of the three-jaw centering chuck is larger than the maximum diameter of the three-pin support body. Combined with a detachable boss structure and locking pin, this design allows for flexible support of the three-pin support with varying heights. When the universal joint of the three-pin support is at its lowest point, screwing in the boss lifts the workpiece center, allowing the universal joint to rest on the top surface of the chuck. When the lowest point of the universal joint is higher than the body structure, removing the boss allows for a recessed placement of the workpiece, with the journal resting on the upper chuck surface. This design increases the number of support points and the distance between them. Attached Figure Description

[0017] Figure 1 A schematic diagram of the overall structure of the centering chuck used for machining three-pin supports is shown; Figure 2 Showing Figure 1 A schematic diagram of the middle structure after removing the upper plate, two claws, and protrusions; Figure 3A schematic diagram of the upper disc body, the screw spool, and the bevel gear is shown; Figure 4 A schematic diagram of the upper plate structure is shown; Figure 5 A schematic diagram of the jaws and locking pins is shown. Figure 6 A schematic diagram of the chuck's structure is shown; Figure 7 A schematic diagram of the card post structure is shown; Figure 8 A schematic diagram of the insert post structure is shown; Figure 9 A schematic diagram of the card post structure is shown; Figure 10 A schematic diagram of the insert post structure is shown.

[0018] In the figure: 1. Claw 1, 1a first through hole, 2. Claw post 2, 3. Insert post 3, 101 lower plate, 102 bevel gear, 103 screw spool, 201 upper plate, 202 guide rail, 203 protrusion, 4. Handle. Detailed Implementation

[0019] A centering chuck for machining three-pin supports, reference Figure 1 , 2 7 and 8 include a three-jaw centering chuck. Each of the three jaws 1 of the three-jaw centering chuck has a locking pin 2 inserted into it. The axes of the three locking pins 2 pass horizontally through the central axis of the three-jaw centering chuck. Each jaw 1 has a pin 3 inserted into it. The pin 3 passes from top to bottom through the locking pin 2 within its own jaw 1. The pin 3 restricts the radial and circumferential degrees of freedom of the locking pin 2, while the jaw 1 restricts the longitudinal degree of freedom of the locking pin 2, thereby fixing the locking pin 2 to the jaw 1.

[0020] Among them, combined Figure 9 and 10 The jaw 1 has a longitudinally arranged array of first through holes 1a. The locking pin 2 can be inserted into any one of the first through holes 1a to achieve a clearance fit. The jaw 1 has a longitudinally arranged second through hole 1b that communicates with all the first through holes 1a. The locking pin 2 has a radially arranged array of third through holes 2a. Radially moving the locking pin 2 allows the second through hole 1b to communicate with any one of the longitudinal third through holes 2a. Inserting the pin 3 into the second through hole 1b and through the third through hole 2a fixes the relative position of the locking pin 2 and the jaw 1. At this time, the locking pin 2 protrudes from the jaw 1 and points towards the central axis of the three-jaw centering chuck. For a temporary, detachable connection, the top of the pin 3 can magnetically attract the top of the jaw 1.

[0021] Working principle: Place the center of the three-pin holder on the upper surface of the three-jaw centering chuck, and adjust the distance between the three jaws 1 so that the three pins 2 simultaneously abut against the outer wall of the center of the three-pin holder.

[0022] The optimized three-jaw centering chuck has a top center diameter larger than the maximum diameter of the three-pin carrier's main body structure, excluding the universal joint portion. The boss 203 is screwed into the top of the three-jaw centering chuck using either a fixed or threaded connection, ensuring it is positioned within the top center opening. The fixed connection method is for fixed three-pin carrier products, while the threaded connection method is for variable three-pin carrier products. See details for further information. Figure 4 If a screw-in design is used, an internal hexagonal notch can be added to the top of the boss 203 to facilitate the rotation of the boss 203 using a hexagonal hardware tool. When the universal joint of the three-pin frame is at its lowest point, the boss 203 can be raised, lifting the center of the three-pin frame above the top surface of the three-jaw centering chuck, allowing the universal joint of the three-pin frame to rest on the top surface of the three-jaw centering chuck. When the lowest position of the universal joint of the three-pin frame is higher than the lowest point of the main body structure at the center of the three-pin frame, the boss 203 can be removed, and the main body structure of the three-pin frame can be placed into the central circular opening at the top of the three-jaw centering chuck for a recessed placement, allowing the universal joint of the three-pin frame to rest on the upper surface of the upper plate 201.

[0023] The three-jaw centering chuck is a general-purpose manual three-jaw centering chuck. Modifying its dimensions does not depart from the meaning expressed in this application. For example, the three-jaw centering chuck includes a lower chuck body 101 and an upper chuck body 201 fixed to the upper end of the lower chuck body 101. A bevel gear 102 is rotatably connected between the lower chuck body 101 and the upper chuck body 201. The lower chuck body 101 and the upper chuck body 201 limit the bevel gear 102, so that the bevel gear 102 only has the degree of freedom to rotate around its own axis. Further, a threaded spool 103 is rotatably connected inside the lower chuck body 101 and the upper chuck body 201. The planar thread of the threaded spool 103 faces upward, and the tooth surface of the threaded spool 103 faces downward and meshes with the bevel gear 102. A handle 4 is fixed externally to the bevel gear 102. The lower chuck body 101 and the upper chuck body 201 limit the threaded spool 103, so that the threaded spool 103 only has the degree of freedom to rotate around its own axis. The upper plate 201 is provided with three circumferentially distributed guide rails 202, and three jaws 1 are slidably connected to the three guide rails 202. The guide rails 202 allow the three jaws 1 to have only radial degrees of freedom. The bottom of the three jaws 1 can be connected to the planar threaded drive at the top of the screw spool 103. When the bevel gear 102 drives the screw spool 103 to rotate, the screw spool 103 can drive the three jaws 1 to move closer or further away synchronously. The boss 203 is threadedly connected to the upper plate 201, and the boss 203 can enter the circular opening of the screw spool 103 and the circular opening of the lower plate 101.

[0024] For example, referring to the prior art of a three-pin bracket and a three-ball pin universal joint with publication number CN117703945A: the locking pin 2 of this application is used to abut against the outer surface of its connecting part, specifically at the intersection of the first curve and the second curve. Since the bottom of the journal in the prior art is higher than the bottom of the body, the boss 203 should be removed so that the body sinks into the central circular opening of the upper plate 201. This allows the journal to be placed on the upper surface of the upper plate 201, thereby increasing the number of support points and the extension distance, making the three-pin bracket with a height difference at the bottom more stable.

Claims

1. A centering chuck for machining three-pin supports, characterized in that, The chuck includes a three-jaw centering chuck, on which three jaws (1) are detachably connected to chuck pins (2). The chuck pins (2) protrude from the jaws (1) in the center direction of the three-jaw centering chuck. The inner ends of the three chuck pins (2) are located on a virtual circle. The axes of the three chuck pins (2) intersect and the intersection point is located at the center of the virtual circle.

2. The centering chuck for machining a three-pin frame according to claim 1, characterized in that, The claw (1) is provided with a first through hole (1a), and the pin (2) can be inserted into the first through hole (1a). The claw (1) is provided with a second through hole (1b) that is longitudinal and communicates with the first through hole (1a). The pin (3) is inserted into the second through hole (1b) and passes through the third through hole (2a) to fix the relative position of the pin (2) and the claw (1).

3. The centering chuck for machining a three-pin frame according to claim 2, characterized in that, The locking post (2) is provided with a radially arrayed third through hole (2a). When the locking post (2) is moved radially, the second through hole (1b) can be connected to any one of the third through holes (2a) in the longitudinal direction.

4. The centering chuck for machining a three-pin frame according to claim 2, characterized in that, The first through holes (1a) are arranged in a longitudinal array on the claw (1), and the second through holes (1b) are connected to all the first through holes (1a).

5. The centering chuck for machining a three-pin frame according to claim 2, characterized in that, The top of the insert (3) can magnetically attach to the top of the claw (1).

6. The centering chuck for machining a three-pin frame according to claim 1, characterized in that, The diameter of the central opening at the top of the claw centering chuck is greater than the maximum diameter of the three pin brackets (5) excluding the universal joint.

7. The centering chuck for machining a three-pin frame according to claim 6, characterized in that, It also includes a boss (203), which is screwed into the top of the three-jaw centering chuck by means of a threaded connection, so that the boss (203) is located in the center circle of the top of the three-jaw centering chuck.

8. The centering chuck for machining a three-pin frame according to claim 7, characterized in that, When the universal joint of the three-pin bracket (5) is at its lowest point, the boss (203) raises the center of the three-pin bracket (5) above the top surface of the three-jaw centering chuck, and the universal joint of the three-pin bracket (5) is placed on the top surface of the three-jaw centering chuck. When the lowest position of the universal joint of the three-pin frame (5) is higher than the lowest point of the main body structure at the center of the three-pin frame (5), take out the boss (203), put the main body structure of the three-pin frame (5) into the central round hole at the top of the three-jaw centering chuck to achieve a sunken placement, and place the universal joint of the three-pin frame (5) on the upper surface of the upper plate (201).

9. The centering chuck for machining a three-pin frame according to claim 1, characterized in that, The centering chuck is a manual three-jaw centering chuck.

10. The centering chuck for machining a three-pin frame according to claim 9, characterized in that, The transmission principle of a manual three-jaw centering chuck is based on the transmission between bevel gears and a screw spool.

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