A finishing clamp

Abstract

The application relates to a fine turning clamp, which comprises a flange seat serving as a basic supporting part of the whole clamp, a backrest detachably connected to the flange seat and provided with a plug-in hole, a positioning core shaft detachably connected to the flange seat, one end of the positioning core shaft being coaxial with the plug-in hole and extending to the outside, an expansion sleeve sleeved on one side of the positioning core shaft extending to the outside, a pull rod with one end fixedly connected to the expansion sleeve and the other end coaxially extending to the flange seat through the positioning core shaft, a floating center slidingly connected to the backrest and provided with a spring, the spring always driving the floating center to move to one side of the expansion sleeve, and a driving source for driving the movement of the pull rod; the backrest realizes rigid support of the shaft shoulder end face, the positioning core shaft provides a radial reference for the inner hole of the matched part, the expansion sleeve and the floating center form bidirectional constraint from the inner hole and the shaft head end part respectively, the driving source linkage completes the clamping action, and the machining stability of the part is improved.

Description

Technical Field

[0001] This utility model relates to the field of CNC lathe fixture technology, and in particular to a precision lathe fixture. Background Technology

[0002] Fixtures are the core tooling in machining, used to position and clamp workpieces to ensure machining accuracy and efficiency. Their structure is adaptable to different workpiece types and can integrate functions such as quick change and centering. They achieve stable clamping through mechanical linkage and are widely used in various manufacturing scenarios.

[0003] like Figure 6 As shown, it is a bushing type part with a coaxial inner hole and a shoulder diameter larger than the head diameter. When turning, a hydraulic chuck is usually used to clamp the head part, but the clamping amount is small, resulting in poor machining stability. Utility Model Content

[0004] To improve the machining stability of parts, this application provides a precision machining fixture.

[0005] The precision machining fixture provided in this application adopts the following technical solution: A precision machining fixture, comprising: The flange seat is the basic support component of the entire fixture. The backrest is detachably connected to the flange seat and has a plug hole that can be matched with the shaft head; The positioning mandrel can be fitted with the inner hole of the part. It is detachably connected to the flange seat, and one end of it is coaxial and has a plug hole to the outside. An expansion sleeve is fitted onto the side of the positioning mandrel that is located to the outside. The tie rod has one end fixedly connected to the expansion sleeve, and the other end coaxially passes through the positioning mandrel into the flange seat; the floating center is slidably connected to the backing and is equipped with a spring, which always drives the floating center to move towards the expansion sleeve. A drive source, which is used to drive the movement of the lever; When the part is installed on the fixture, the inner hole of the part mates with the positioning mandrel, the shaft head mates with the insertion hole, the end face of the shaft shoulder abuts against the backing, the expansion sleeve is located in the inner hole, the drive source drives the pull rod to move to expand the expansion sleeve, and the floating center moves to abut against the end of the shaft head.

[0006] By adopting the above technical solution, a composite clamping system of "end face positioning + inner hole centering + dual-point clamping" is constructed. Based on the flange seat, the backrest provides rigid support for the shoulder end face. The positioning mandrel adapts to the inner hole of the part to provide a radial reference. The expansion sleeve and floating center form bidirectional constraints from the inner hole and the end of the shaft, respectively. The drive source links to complete the clamping action, thereby improving the machining stability of the part.

[0007] Preferably, the expansion sleeve has a hollow frustum structure, and its inner wall is adapted to the conical end of the positioning mandrel extending to the outside. The outer wall of the expansion sleeve has elastic grooves evenly distributed along the circumference.

[0008] By adopting the above technical solution, the expansion sleeve is defined as "hollow frustum structure + conical surface fit + circumferential elastic groove". The expansion sleeve is pulled axially by the tie rod, and radial uniform expansion is achieved by the conical surface guide. The local clamping of the shaft head is achieved. The surface contact method between the expansion sleeve and the inner hole avoids the point indentation of the shaft head by the traditional chuck claw, thus protecting the appearance quality of the parts.

[0009] Preferably, the outer wall of the expansion sleeve is wrapped with a layer of wear-resistant rubber, and the surface of the wear-resistant rubber layer is provided with anti-slip texture extending along the axial direction.

[0010] By adopting the above technical solution, a wear-resistant rubber layer and axial anti-slip texture are added to the outer wall of the expansion sleeve, optimizing the contact characteristics between the expansion sleeve and the inner hole of the part, and solving the drawbacks of hard contact between the traditional metal chuck and the workpiece.

[0011] Preferably, the end of the floating tip closest to the expansion sleeve is the tightening end, which can be moved into the insertion groove, and the tightening end has a frustum structure.

[0012] By adopting the above technical solution, the clamping end of the floating center is designed as a frustum structure that can extend into the insertion hole, thus optimizing the clamping constraint at the end of the shaft head. The frustum structure has a built-in centering function, which can automatically compensate for minor coaxiality deviations when the parts are clamped.

[0013] Preferably, the floating tip is sleeved on the positioning mandrel, and the side of the floating tip away from the tightening end is provided with a plurality of first grooves. The positioning mandrel is provided with a plurality of second grooves. There are a plurality of springs, one end of each of the plurality of springs is placed in a plurality of first grooves and abuts against the bottom of the first groove, and the other end of each of the plurality of springs is placed in a plurality of second grooves and abuts against the bottom of the second groove.

[0014] By adopting the above technical solution, the floating tip is sleeved on the positioning mandrel, and the spring is arranged in a regular manner through the first groove and the second groove, so that the elastic clamping force of the floating tip is stably transmitted, reducing the possibility of skewing and fluctuation of clamping force, similar to traditional tip springs.

[0015] Preferably, the drive source includes a connecting rod and a hydraulic cylinder. The pull rod is fixedly connected to the connecting rod, the connecting rod is slidably connected to the flange seat, the connecting rod is provided with an inclined guide rail, the hydraulic cylinder is fixedly connected to the flange seat, and one end of the piston rod of the hydraulic cylinder is slidably connected to the inclined guide rail.

[0016] By adopting the above technical solution and using a transmission structure of "cylinder + connecting rod + inclined guide rail", the linear motion of the cylinder is converted into the axial movement of the connecting rod, providing stable power for the expansion sleeve to tighten.

[0017] Preferably, an observation hole is provided on the side of the mountain, and the observation hole is connected to the insertion hole.

[0018] By adopting the above technical solution, an observation hole connected to the insertion hole is opened on the side of the backing, so as to realize the visual inspection of the clamping status. Operators can intuitively confirm the insertion depth of the shaft head and the fit between the shaft shoulder and the backing through the observation hole, and promptly detect clamping problems, avoiding scrap due to positioning failure. It is also convenient to observe the tightening status of the floating center during the first piece debugging, ensuring the compatibility between the fixture and the part, and reducing debugging costs.

[0019] The main technical effects of this utility model are reflected in the following aspects: 1. This utility model constructs a composite clamping system of "end face positioning + inner hole centering + double point clamping". Based on the flange seat, the backrest provides rigid support for the shoulder end face. The positioning mandrel adapts to the inner hole of the part to provide radial reference. The expansion sleeve and floating center form bidirectional constraints from the inner hole and the end of the shaft head, respectively. The drive source links to complete the clamping action, thereby improving the machining stability of the part. 2. The expansion sleeve of this utility model is defined as "hollow frustum structure + conical surface fit + circumferential elastic groove". The expansion sleeve is pulled axially by the tie rod and radially uniformly expanded by the conical surface guide. It locally clamps the shaft head. The surface contact method between the expansion sleeve and the inner hole avoids the point indentation of the shaft head by the traditional chuck claw and protects the appearance quality of the parts. 3. This utility model has an observation hole on the side of the backrest that communicates with the insertion hole, so as to realize the visual inspection of the clamping status. The operator can directly confirm the insertion depth of the shaft head and the fit between the shaft shoulder and the backrest through the observation hole, and promptly detect the problem of improper clamping, so as to avoid scrap due to positioning failure. It is also convenient to observe the tightening status of the floating center during the first piece debugging, to ensure the compatibility between the fixture and the part, and to reduce the debugging cost. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application.

[0021] Figure 2 This is a cross-sectional view of the overall structure of an embodiment of this application.

[0022] Figure 3 This is a schematic diagram of the state of the part after it is clamped according to an embodiment of this application.

[0023] Figure 4 This is a schematic diagram of the overall structure and installation of an embodiment of this application.

[0024] Figure 5 This is a schematic diagram of the expansion sleeve structure according to an embodiment of this application.

[0025] Figure 6This is a schematic diagram of the component structure in an embodiment of this application.

[0026] Explanation of reference numerals in the attached drawings: 1. Flange seat; 2. Backing; 3. Positioning mandrel; 4. Expansion sleeve; 5. Tie rod; 6. Floating center; 7. Spring; 8. Drive source; 9. Insertion hole; 10. Elastic groove; 11. Wear-resistant rubber layer; 12. Anti-slip texture; 13. Tightening end; 14. First groove; 15. Second groove; 16. Connecting rod; 17. Hydraulic cylinder; 18. Inclined guide rail; 19. Piston rod; 20. Observation hole; 21. Part; 22. Shaft head; 23. Shaft shoulder; 24. Inner hole. Detailed Implementation

[0027] The following is in conjunction with the appendix Figure 1-6 This application will be described in further detail to make the technical solution of this application easier to understand and master.

[0028] Reference Figure 2 and Figure 4 This embodiment of a precision machining fixture includes: a flange seat 1, which is the basic support component of the entire fixture; a backrest 2, which is detachably connected to the flange seat 1 by bolts and has an insertion hole 9 that can cooperate with the shaft head 22; a positioning mandrel 3, which can cooperate with the inner hole 24 of the part 21, one end of which is detachably connected to the flange seat 1 by bolts and located inside the backrest 2, and the other end of which is coaxial and passes through the insertion hole 9 to the outside; an expansion sleeve 4, which is sleeved on the side of the positioning mandrel 3 located outside; a pull rod 5, one end of which is fixedly connected to the expansion sleeve 4, and the other end of which coaxially passes through the positioning mandrel 3 to the flange seat 1 and is coaxially slidably connected to the flange seat 1; a floating tip 6, which is coaxially and slidably connected inside the backrest 2 and is equipped with a spring 7, which always drives the floating tip 6 to move towards the expansion sleeve 4; and a drive source 8, which is used to drive the movement of the pull rod 5.

[0029] Reference Figure 3 When part 21 is installed on the fixture, the inner hole 24 of part 21 mates with the positioning mandrel 3, the shaft head 22 mates with the insertion hole 9, the end face of the shaft shoulder 23 abuts against the backrest 2, the expansion sleeve 4 is located in the inner hole 24, the drive source 8 drives the pull rod 5 to move and cause the expansion sleeve 4 to expand, and the floating tip 6 moves to abut against the end of the shaft head 22.

[0030] Reference Figure 3 A composite clamping system of "end face positioning + inner hole 24 centering + double point clamping" is constructed. Based on the flange seat 1, the backrest 2 provides rigid support for the end face of the shoulder 23, the positioning mandrel 3 adapts to the inner hole 24 of the part 21 to provide radial reference, the expansion sleeve 4 and the floating center 6 form bidirectional constraints from the inner hole 24 and the end of the shaft head 22 respectively, and the drive source 8 completes the clamping action in conjunction to improve the machining stability of the part 21.

[0031] Reference Figure 5The expansion sleeve 4 has a hollow frustum structure, and its inner wall is adapted to the conical surface of the end of the positioning mandrel 3 extending to the outside. The outer wall of the expansion sleeve 4 has elastic grooves 10 evenly distributed circumferentially. The expansion sleeve 4 is defined as "hollow frustum structure + conical surface fit + circumferential elastic groove 10". The expansion sleeve 4 is axially pulled by the pull rod 5, and radial uniform expansion is achieved by using the conical surface guide to locally clamp the shaft head 22. The surface contact method between the expansion sleeve 4 and the inner hole 24 avoids the point indentation of the shaft head 22 by the traditional chuck claws, thus protecting the appearance quality of the part 21.

[0032] Reference Figure 5 The outer wall of the expansion sleeve 4 is covered with a layer of wear-resistant rubber 11, and the surface of the wear-resistant rubber layer 11 is provided with anti-slip textures 12 extending along the axial direction. The addition of the wear-resistant rubber layer 11 and the axial anti-slip textures 12 to the outer wall of the expansion sleeve 4 optimizes the contact characteristics between the expansion sleeve 4 and the inner hole 24 of the part 21, and solves the drawbacks of hard contact between the traditional metal chuck and the workpiece.

[0033] Reference Figure 3 and Figure 4 The end of the floating tip 6 closest to the expansion sleeve 4 is designated as the clamping end 13. The clamping end 13 can be moved into the insertion slot, and the clamping end 13 has a frustum structure. By designing the clamping end 13 of the floating tip 6 as a frustum structure that can extend into the insertion hole 9, the clamping constraint at the end of the shaft head 22 is optimized. The frustum structure has a built-in centering function, which can automatically compensate for minor coaxiality deviations when the part 21 is clamped.

[0034] Reference Figure 3 and Figure 4 A floating tip 6 is sleeved on a positioning spindle 3. The side of the floating tip 6 away from the tightening end 13 has several first grooves 14. The positioning spindle 3 has several second grooves 15. Several springs 7 are present, with one end of each spring 7 placed in one of the first grooves 14 and abutting against the bottom of the first groove 14. The other end of each spring 7 is placed in one of the second grooves 15 and abutting against the bottom of the second groove 15. This arrangement of the floating tip 6 on the positioning spindle 3, along with the regular arrangement of the springs 7 through the first and second grooves 14 and 15, ensures stable transmission of the elastic tightening force of the floating tip 6, reducing the possibility of skewing and fluctuations in tightening force, similar to traditional tip springs 7.

[0035] Reference Figure 3 and Figure 4 The drive source 8 includes a connecting rod 16 and a hydraulic cylinder 17. A pull rod 5 is fixedly connected to the connecting rod 16, which is slidably connected to the flange seat 1. An inclined guide rail 18 is provided on the connecting rod 16. The hydraulic cylinder 17 is fixedly connected to the flange seat 1, and one end of the piston rod 19 of the hydraulic cylinder 17 is slidably connected within the inclined guide rail 18. This transmission structure of "hydraulic cylinder 17 + connecting rod 16 + inclined guide rail 18" converts the linear motion of the hydraulic cylinder 17 into the axial movement of the pull rod 5, providing stable power for the tightening of the expansion sleeve 4.

[0036] Reference Figure 1 An observation hole 20 is provided on the side of the support 2, which is connected to the insertion hole 9. The observation hole 20, which is connected to the insertion hole 9, allows for visual inspection of the clamping status. Operators can visually confirm the insertion depth of the shaft head 22 and the fit between the shaft shoulder 23 and the support 2 through the observation hole 20, so as to promptly detect clamping problems and avoid scrap due to positioning failure. It also facilitates the observation of the tightening status of the floating center 6 during the first piece debugging, ensuring the compatibility between the fixture and the part 21 and reducing debugging costs.

[0037] Of course, the above are merely typical examples of this application. Besides these, this application may have many other specific implementations. All technical solutions formed by equivalent substitution or equivalent transformation fall within the scope of protection claimed in this application.

Claims

1. A precision machining fixture, characterized in that, include: Flange seat (1), which is the basic support component of the entire fixture; The backing (2) is detachably connected to the flange seat (1) and has a plug hole (9) that can be matched with the shaft head (22); The positioning mandrel (3) can be fitted with the inner hole (24) of the part (21), and it is detachably connected to the flange seat (1). One end of the mandrel is coaxial and passes through the insertion hole (9) to the outside. The expansion sleeve (4) is fitted onto the side of the positioning mandrel (3) located on the outside. A pull rod (5) has one end fixedly connected to the expansion sleeve (4) and the other end coaxially passes through the positioning mandrel (3) to the flange seat (1); a floating tip (6) is slidably connected to the backing (2) and is equipped with a spring (7), which always drives the floating tip (6) to move toward the expansion sleeve (4); A drive source (8) is used to drive the movement of the pull rod (5); When part (21) is installed on the fixture, the inner hole (24) of part (21) is engaged with the positioning mandrel (3), the shaft head (22) is engaged with the insertion hole (9), the end face of the shaft shoulder (23) abuts against the backrest (2), the expansion sleeve (4) is located in the inner hole (24), the drive source (8) drives the pull rod (5) to move to expand the expansion sleeve (4), and the floating tip (6) moves to abut against the end of the shaft head (22).

2. The precision machining fixture according to claim 1, characterized in that: The expansion sleeve (4) is a hollow frustum structure, and its inner wall is adapted to the end conical surface of the positioning mandrel (3) extending to the outside. The outer wall of the expansion sleeve (4) is uniformly distributed with elastic grooves (10) along the circumference.

3. A precision machining fixture according to claim 2, characterized in that: The outer wall of the expansion sleeve (4) is covered with a layer of wear-resistant rubber (11), and the surface of the wear-resistant rubber layer (11) is provided with anti-slip textures (12) extending along the axial direction.

4. A precision machining fixture according to claim 1, characterized in that: Make the end of the floating tip (6) close to the expansion sleeve (4) the tightening end (13), the tightening end (13) can be moved into the insertion groove, and the tightening end (13) is a frustum structure.

5. A precision machining fixture according to claim 3, characterized in that: The floating tip (6) is sleeved on the positioning mandrel (3). The side of the floating tip (6) away from the tightening end (13) is provided with a plurality of first grooves (14). The positioning mandrel (3) is provided with a plurality of second grooves (15). The spring (7) is provided with a plurality of springs. One end of each spring (7) is placed in a plurality of first grooves (14) and abuts against the bottom of the first groove (14). The other end of each spring (7) is placed in a plurality of second grooves (15) and abuts against the bottom of the second groove (15).

6. A precision machining fixture according to claim 1, characterized in that: The drive source (8) includes a connecting rod (16) and a hydraulic cylinder (17). The pull rod (5) is fixedly connected to the connecting rod (16). The connecting rod (16) is slidably connected to the flange seat (1). An inclined guide rail (18) is provided on the connecting rod (16). The hydraulic cylinder (17) is fixedly connected to the flange seat (1). One end of the piston rod (19) of the hydraulic cylinder (17) is slidably connected to the inclined guide rail (18).

7. A precision machining fixture according to claim 1, characterized in that: An observation hole (20) is provided on the side of the backrest (2), and the observation hole (20) is connected to the insertion hole (9).

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