A rubber expansion sleeve type turning fixture without axial displacement

Abstract

The utility model relates to a rubber expansion sleeve type turning clamp without axial displacement, which comprises a clamp body, a pull rod and a rubber expansion sleeve, the rubber expansion sleeve is located above the clamp body and is in contact with the clamp body, the pull rod moves axially relative to the clamp body, the rubber expansion sleeve is sleeved outside the pull rod, an inner taper surface in the form of an inverted cone is formed on the inner side of the through hole of the rubber expansion sleeve, an outer taper surface in the form of an inverted cone is formed on the outer side of the pull rod, and the inner taper surface of the rubber expansion sleeve is in contact with the outer taper surface of the pull rod. When the rubber expansion sleeve expands to clamp a workpiece, the rubber expansion sleeve does not move axially, the axial force on the workpiece is reduced, and the degree of deformation of the workpiece during clamping is reduced. The pull rod adopts an outer hexagonal pyramid structure, the rubber expansion sleeve adopts an inner hexagonal taper hole, the inner and outer hexagonal pyramids cooperate with each other, after the clamp is clamped, the six pairs of planes of the inner and outer hexagonal pyramids are in contact, the inner and outer hexagonal pyramids can withstand a large torque during processing, the inner and outer hexagonal pyramids are limited by the edges and corners, and the rubber expansion sleeve and the pull rod are prevented from rotating along the central axis.

Description

Technical Field

[0001] This utility model relates to the field of fixtures, and in particular to a rubber expansion sleeve type turning fixture with no axial displacement. Background Technology

[0002] As parts are designed to be increasingly lightweight, the wall thickness and other parameters of customer-designed workpieces are approaching their limits while still meeting strength requirements. This leads to clamping deformation issues during actual turning, resulting in consistently low yield rates and hindering large-scale production efficiency. Conventional pull-back fixtures typically have high pull forces. The expansion of the rubber sleeve relative to the workpiece's axial movement creates additional axial forces. For thin-walled, easily deformable workpieces, excessive axial forces can cause deformation during clamping.

[0003] Traditional rubber expansion sleeve clamps work by engaging the conical surfaces of the pull rod and the rubber expansion sleeve when the clamp is tightened, causing the sleeve to expand. However, because there is no anti-rotation structure between the rubber expansion sleeve and the pull rod, they can slip under high torque conditions, preventing the rubber expansion sleeve from withstanding excessive torque. Utility Model Content

[0004] The present invention aims to solve the above problems by providing a rubber expansion sleeve type turning fixture with no axial displacement, thereby solving the aforementioned problems.

[0005] A rubber expansion sleeve type turning fixture with no axial displacement includes: a fixture body, a tie rod, and a rubber expansion sleeve. The rubber expansion sleeve is located above the fixture body and contacts the fixture body. The tie rod moves axially relative to the fixture body. The rubber expansion sleeve is fitted on the outside of the tie rod. An inverted conical inner conical surface is formed on the inner side of the through hole of the rubber expansion sleeve, and an inverted conical outer conical surface is formed on the outside of the tie rod. The inner conical surface of the rubber expansion sleeve contacts the outer conical surface of the tie rod.

[0006] Preferably, the inner and outer conical surfaces are the lateral surfaces of a pyramid, and the edges of the inner and outer conical surfaces correspond one-to-one, with the corresponding edges located in the same plane.

[0007] Preferably, the inner and outer conical surfaces are the lateral surfaces of a hexagonal pyramid.

[0008] Preferably, the rubber expansion sleeve includes rubber blocks and metal blocks, with multiple metal blocks and multiple rubber blocks arranged alternately in a circle. The two sides of each metal block are fixedly connected to adjacent rubber blocks, and all rubber blocks form pyramidal edges.

[0009] Preferably, the rubber expansion sleeve includes a main body and a flange, the diameter of the flange is larger than that of the main body, the flange is located on the side of the main body close to the clamp body and is integrally formed with the main body, a boss is formed on the top of the clamp body, and the flange fits against the end face of the boss.

[0010] Preferably, it further includes a support base, which is fixedly connected to the clamp body. The support base is fitted onto the outside of the rubber expansion sleeve and the boss, and the support base covers the upper part of the flange.

[0011] Preferably, it further includes a guide block, which is disposed above the boss. The guide block is fixedly connected to the boss or moves radially only relative to the boss. A radial second groove is formed below the flange, and the guide block is inserted into the second groove and slidably connected to the second groove.

[0012] Preferably, the pull rod includes a cone head, a connecting rod, and a threaded rod, the cone head, the connecting rod, and the threaded rod being coaxial, the upper and lower ends of the connecting rod being integrally formed with the cone head and the threaded rod respectively, and the outer cone surface being located at the cone head; it also includes a pull shaft body, the pull shaft body being threadedly connected to the threaded rod, the pull shaft body being located inside the clamp body and slidingly connected to the inner wall of the clamp body.

[0013] Preferably, it also includes an anti-rotation screw, wherein an axial first groove is formed on the side of the connecting rod, the anti-rotation screw is radially inserted into the first groove, the anti-rotation screw is threadedly connected to the clamp body, and the first groove is slidably connected to the anti-rotation screw.

[0014] Preferably, it also includes a cylindrical pin, the two ends of which are respectively inserted into the axial through hole of the clamp body and the axial through hole of the pull shaft body.

[0015] This utility model has the following advantages: When the rubber expansion sleeve expands and clamps the workpiece, the rubber expansion sleeve is limited by the contact between the fixture body and the lower end face of the rubber expansion sleeve, so the rubber expansion sleeve will not move axially, reducing the axial force on the workpiece and thus reducing the deformation of the workpiece during clamping; the pull rod adopts an external hexagonal pyramid structure, and the rubber expansion sleeve adopts an internal hexagonal pyramid hole. The internal and external hexagonal pyramids cooperate with each other. After the fixture clamps, the six pairs of planes of the internal and external hexagonal pyramids fit together, ensuring that they can withstand large torques during processing. The internal and external hexagonal pyramids also have mutually restrictive edges and corners to prevent the rubber expansion sleeve and pull rod from rotating along the central axis. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 one embodiment of this utility model. For those skilled in the art, other embodiments can be derived from the provided drawings without creative effort.

[0017] Figure 1 : A three-dimensional structural schematic diagram of this utility model; Figure 2 : A three-dimensional structural diagram of this utility model after removing the support base; Figure 3 : A three-dimensional structural diagram of the tie rod; Figure 4 : A three-dimensional structural diagram of a rubber expansion sleeve; Figure 5 : A top view of the structure of this utility model; Figure 6 :exist Figure 5 A schematic diagram of the rotated cross-sectional structure at point AA. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and examples: The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0019] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0020] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model. like Figures 1 to 6As shown, a rubber expansion sleeve type turning fixture without axial displacement includes: a fixture body 1, a pull rod 2, and a rubber expansion sleeve 3. The rubber expansion sleeve 3 is located above the fixture body 1 and in contact with the fixture body 1. The pull rod 2 moves axially relative to the fixture body 1. The rubber expansion sleeve 3 is fitted on the outside of the pull rod 2. An inverted conical inner conical surface 30 is formed on the inner side of the through hole of the rubber expansion sleeve 3. An inverted conical outer conical surface 20 is formed on the outside of the pull rod 2. The inner conical surface 30 of the rubber expansion sleeve 3 is in contact with the outer conical surface 20 of the pull rod 2.

[0021] During operation, the workpiece is fitted onto the outside of the rubber expansion sleeve 3, and the pull rod 2 moves downward axially. The outer conical surface 20 presses against the inner conical surface 30, causing the rubber expansion sleeve 3 to expand radially outward. The rubber expansion sleeve 3 contacts the inner hole of the workpiece, fixing the workpiece to the rubber expansion sleeve 3. When the rubber expansion sleeve 3 expands, because the clamp body 1 contacts the lower end face of the rubber expansion sleeve 3, limiting the rubber expansion sleeve 3, the rubber expansion sleeve 3 will not move axially, reducing the axial force on the workpiece and thus reducing the degree of workpiece clamping deformation. When releasing the workpiece, the pull rod 2 moves upward axially, the outer conical surface 20 no longer presses against the inner conical surface 30, and the rubber expansion sleeve 3 springs back and contracts radially, creating a gap with the inner hole of the workpiece.

[0022] Preferably, the inner conical surface 30 and the outer conical surface 20 are the lateral surfaces of the pyramid, and the edges of the inner conical surface 30 and the outer conical surface 20 correspond one-to-one, with the corresponding edges located in the same plane. Compared with the prior art where the rubber expansion sleeve and the tie rod of the conical surface are held in place only by friction, the lateral surface of the pyramid uses a mechanical structure to prevent the rubber expansion sleeve 3 from rotating relative to the tie rod 2, avoiding slippage and allowing it to withstand greater torque. It should be noted that the inner conical surface 30 and the outer conical surface 20 are the lateral surfaces of a segment of the axial section of the pyramid, not necessarily the entire lateral surface of the pyramid.

[0023] Preferably, the inner conical surface 30 and the outer conical surface 20 are the side surfaces of a hexagonal pyramid.

[0024] Preferably, the rubber expansion sleeve 3 includes rubber blocks 33 and metal blocks 34, with multiple metal blocks 34 and multiple rubber blocks 33 arranged alternately in a circle. The two sides of the metal blocks 34 are fixedly connected to the adjacent rubber blocks 33 respectively, and all the rubber blocks 33 form pyramidal edges.

[0025] Preferably, the rubber expansion sleeve 3 includes a main body 31 and a flange 32. The diameter of the flange 32 is larger than that of the main body 31. The flange 32 is located on the side of the main body 31 near the clamp body 1 and is integrally formed with the main body 31. A boss 11 is formed on the upper part of the clamp body 1, and the flange 32 fits against the end face of the boss 11. The flange 32 increases the contact area with the boss 11 and reduces the pressure.

[0026] Preferably, it also includes a support base 5, which is fixedly connected to the clamp body 1. The support base 5 is fitted on the outside of the rubber expansion sleeve 3 and the boss 11. The support base 5 covers the upper part of the flange 32, reducing the entry of chips and cutting fluid into the connection between the flange 32 and the boss 11.

[0027] Preferably, the assembly also includes a guide block 7, which is disposed above the boss 11. The guide block 7 is fixedly connected to the boss 11 or only moves radially relative to the boss 11. A radial second groove 321 is formed below the flange portion 32, and the guide block 7 is inserted into and slidably connected to the second groove 321. The guide block 7 serves as a limiting structure between the rubber expansion sleeve 3 and the boss 11, preventing the rubber expansion sleeve 3 from rotating relative to the boss 11, thus allowing the rubber expansion sleeve 3 to withstand greater torque.

[0028] Preferably, the pull rod 2 includes a cone head 21, a connecting rod 22, and a threaded rod 23. The cone head 21, the connecting rod 22, and the threaded rod 23 are coaxial. The upper and lower ends of the connecting rod 22 are integrally formed with the cone head 21 and the threaded rod 23, respectively. The outer cone surface 20 is located on the cone head 21. The pull rod 2 also includes a pull shaft body 4, which is threadedly connected to the threaded rod 23. The pull shaft body 4 is located inside the clamp body 1 and is slidably connected to the inner wall of the clamp body 1.

[0029] Preferably, the device further includes an anti-rotation screw 8. An axial first groove 221 is formed on the side of the connecting rod 22. The anti-rotation screw 8 is radially inserted into the first groove 221. The anti-rotation screw 8 is threadedly connected to the clamp body 1, and the first groove 221 is slidably connected to the anti-rotation screw 8. The anti-rotation screw 8 prevents the pull rod 2 from rotating.

[0030] Preferably, the device further includes a cylindrical pin 9, with both ends of the cylindrical pin 9 inserted into the axial through hole of the clamp body 1 and the axial through hole of the pull shaft body 4, respectively. The cylindrical pin 9 prevents the pull shaft body 4 from rotating and, in conjunction with the anti-rotation screw 8, ensures that neither the pull rod 2 nor the pull shaft body 4 rotates, thus preventing the threads from loosening.

[0031] Working principle: The fixture body 1 is fixedly connected to the fixture base 6 via hex socket screws. The fixture base 6 is connected to the lathe's spindle taper via screws. The clamping process is achieved by hydraulic oil supplied by the lathe's hydraulic system, with the oil inlet pipe delivering it to the lathe's rotary cylinder. The piston in the rotary cylinder is driven by the hydraulic oil and connected to the machine tool drawbar. The drawbar drives the pull shaft 4, which in turn drives the pull rod 2 downwards, causing the rubber expansion sleeve 3 to expand along its diameter, ultimately tightening and fixing the workpiece. The workpiece release process is the opposite of the clamping action; after the pull rod 2 is pushed upwards, the metal block of the rubber expansion sleeve 3 contracts inwards along its diameter, achieving the release action.

[0032] For workpieces with different inner diameters within a certain range of specifications, the corresponding rubber expansion sleeve 3 can be replaced to achieve quick tensioning of different workpieces.

[0033] The present invention has been described above by way of example, but the present invention is not limited to the specific embodiments described above. Any modifications or variations made based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A rubber expansion sleeve type turning fixture with no axial displacement, characterized in that, include: The fixture body (1), the pull rod (2), and the rubber expansion sleeve (3) are located above the fixture body (1) and in contact with the fixture body (1). The pull rod (2) moves axially relative to the fixture body (1). The rubber expansion sleeve (3) is fitted on the outside of the pull rod (2). The inner side of the through hole of the rubber expansion sleeve (3) has an inverted conical inner cone surface (30). The outer side of the pull rod (2) has an inverted conical outer cone surface (20). The inner cone surface (30) of the rubber expansion sleeve (3) is in contact with the outer cone surface (20) of the pull rod (2).

2. The rubber expansion sleeve type turning fixture with no axial displacement according to claim 1, characterized in that: The inner cone surface (30) and the outer cone surface (20) are the sides of the pyramid. The edges of the inner cone surface (30) and the outer cone surface (20) correspond one-to-one, and the corresponding edges are located in the same plane.

3. The rubber expansion sleeve type turning fixture with no axial displacement according to claim 2, characterized in that: The inner cone surface (30) and the outer cone surface (20) are the lateral surfaces of a hexagonal pyramid.

4. The rubber expansion sleeve type turning fixture with no axial displacement according to claim 3, characterized in that: The rubber expansion sleeve (3) includes rubber blocks (33) and metal blocks (34). Multiple metal blocks (34) and multiple rubber blocks (33) are arranged alternately in a circle. The two sides of the metal blocks (34) are fixedly connected to the adjacent rubber blocks (33). All the rubber blocks (33) form pyramidal edges.

5. A rubber expansion sleeve type turning fixture with no axial displacement according to claim 1, characterized in that: The rubber expansion sleeve (3) includes a main body (31) and a flange (32). The diameter of the flange (32) is larger than that of the main body (31). The flange (32) is located on the side of the main body (31) close to the clamp body (1) and is integrally formed with the main body (31). A boss (11) is formed on the top of the clamp body (1). The flange (32) is in contact with the end face of the boss (11).

6. A rubber expansion sleeve type turning fixture with no axial displacement according to claim 5, characterized in that: It also includes a support base (5), which is fixedly connected to the clamp body (1). The support base (5) is fitted on the outside of the rubber expansion sleeve (3) and the boss (11). The support base (5) covers the flange portion (32).

7. A rubber expansion sleeve type turning fixture with no axial displacement according to claim 5, characterized in that: It also includes a guide block (7), which is disposed above the boss (11). The guide block (7) is fixedly connected to the boss (11) or moves radially only relative to the boss (11). A radial second groove (321) is formed below the flange (32). The guide block (7) is inserted into the second groove (321) and slidably connected to the second groove (321).

8. A rubber expansion sleeve type turning fixture with no axial displacement according to claim 1, characterized in that: The pull rod (2) includes a cone head (21), a connecting rod (22), and a threaded rod (23). The cone head (21), the connecting rod (22), and the threaded rod (23) are coaxial. The upper and lower ends of the connecting rod (22) are integrally formed with the cone head (21) and the threaded rod (23), respectively. The outer cone surface (20) is located on the cone head (21). The pull rod (2) also includes a pull shaft body (4). The pull shaft body (4) is threadedly connected to the threaded rod (23). The pull shaft body (4) is located inside the clamp body (1) and is slidably connected to the inner wall of the clamp body (1).

9. A rubber expansion sleeve type turning fixture with no axial displacement according to claim 8, characterized in that: It also includes an anti-rotation screw (8), and the side of the connecting rod (22) has an axial first groove (221). The anti-rotation screw (8) is radially inserted into the first groove (221). The anti-rotation screw (8) is threadedly connected to the clamp body (1), and the first groove (221) is slidably connected to the anti-rotation screw (8).

10. A rubber expansion sleeve type turning fixture with no axial displacement according to claim 8, characterized in that: It also includes a cylindrical pin (9), the two ends of which are inserted into the axial through hole of the clamp body (1) and the axial through hole of the pull shaft body (4), respectively.

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