Clamp for grinding outer circle of workpiece

Abstract

The utility model relates to machining of hollow shaft products, in particular to a clamp for grinding an outer circle of a workpiece, and aims to overcome the defects that in the prior art, an outer circle grinding clamp is complex in structure, or the clamp is prone to abrasion and unstable in clamping mode due to the fact that the clamp is clamped through a conical surface. The fixture for grinding the outer circle of the workpiece comprises a central shaft, a deflector rod, a limiting mechanism and a first support, wherein the deflector rod and the limiting mechanism are arranged at one end of the central shaft; the first support sleeves the central shaft and is detachably connected with the central shaft; the center shaft penetrates through a workpiece to be machined, the limiting mechanism is matched with an inner hole in one end of the workpiece, and the outer circle of the first support is matched with an inner hole in the other end of the workpiece. The limiting mechanism and the first support are used for limiting the two ends of the workpiece. The deflector rod is located on the outer side of the limiting mechanism and used for being matched with a rotating mechanism of an external grinding machine to drive the center shaft to rotate.

Description

Technical Field

[0001] The utility model relates to the processing of hollow shaft products, in particular to a clamp for grinding the outer circle of a workpiece. Background Art

[0002] With the popularization of electro-hydraulic products, there are more and more hollow shaft products, and the processing accuracy requirements are getting higher and higher. In order to solve the problem of hollow shaft accuracy after heating, it is necessary to design a special fixture for grinding the outer circle. Hollow gear shaft parts include shaft and disc integrated parts. The tooth accuracy requirement is national standard level 6. The outer circle and inner hole at both ends have cylindricality and coaxiality requirements respectively. This requires the reference cone surface of the part to be very precise, and the roundness is <0.003, in order to meet the processing requirements. After heat treatment, the roundness of the pre-heat positioning cone surface (the inner hole cone surface on both sides) is basically 0.03-0.04mm. Without the reference correction, the subsequent processing cannot be carried out at all. Generally, a special external grinding fixture is used to process the positioning surface, and then the reference cone surface is corrected, and then the post-heat finishing is performed.

[0003] Chinese patent CN204135884U discloses a fixture for grinding the outer cylindrical end face of a half-shaft gear, which includes a spindle, a positioning plate, a tapered sleeve and a stepped expansion sleeve that slides with the tapered surface of the tapered sleeve. The stepped expansion sleeve has a large diameter end and a small diameter end, and the large diameter end is arranged on the end face close to the positioning plate. The half-shaft gear is arranged on the outer circle of the stepped expansion sleeve for processing, but its spindle is arranged in sections, which is easy to deform and the fixture structure is complicated; Chinese patent CN203887254U also discloses a fixture for grinding the outer cylindrical end face, including a fixture, a spindle, a machine tool tailstock, and a center. One end of the spindle is clamped by the fixture, and the center of the other end face is pressed by the center. The clamping part of the fixture is provided with two clamping planes, and the sleeve is fixed on the fixture for processing. One end of the sleeve is clamped by the tapered surface of the spindle. The fixture is prone to wear and the clamping method is unstable, thereby reducing the processing accuracy. Utility Model Content

[0004] The utility model aims to solve the shortcomings of the prior art that the fixture for grinding the outer circle is complex in structure or the fixture is easily worn out and the clamping method is unstable due to the clamping of the conical surface, and to provide a fixture for grinding the outer circle of a workpiece.

[0005] To achieve the above purpose, the technical solutions provided by the utility model are as follows:

[0006] A fixture for grinding the outer circle of a workpiece, which is special in that it includes: a center axis, a lever and a limiting mechanism arranged at one end of the center axis, and a first support arranged at the other end of the center axis; the first support is a cylindrical structure, which is sleeved on the center axis and is detachably connected to the center axis; a first boss is arranged at one end of the outer wall of the first support; the center axis is penetrated into the workpiece to be processed, the limiting mechanism is adapted to the inner hole at one end of the workpiece, and the outer circle of the first support is matched with the inner hole at the other end of the workpiece; the limiting mechanism and the first support are used to limit the two ends of the workpiece; the lever is located on the outside of the limiting mechanism, and is arranged along the radial direction of the center axis, and is detachably connected to the center axis, and the lever cooperates with the rotating mechanism of the external grinder to drive the center axis to rotate.

[0007] Further, the limiting mechanism includes a second support;

[0008] The second support is a cylindrical structure, sleeved on the central shaft, and detachably connected to the central shaft;

[0009] A second boss is disposed at one end of the outer side wall of the second support.

[0010] Furthermore, a third boss is provided on the central axis between the second support and the shifting rod;

[0011] The second boss is arranged close to the third boss and abuts against the inner end surface of the third boss;

[0012] The second boss and the third boss are connected by threads.

[0013] Furthermore, the limiting mechanism includes a reducing section arranged on the central axis, the reducing section includes a conical section arranged on the outer wall of the central axis and a large diameter section connected thereto, the large diameter section is located between the conical section and the shift rod; the conical section cooperates with the auxiliary positioning conical surface at one end of the workpiece to be processed.

[0014] Furthermore, a third boss is arranged on the central axis between the diameter-changing section and the shifting rod.

[0015] Further, the first boss of the first support is arranged close to the other end of the central axis;

[0016] The other end of the central shaft is provided with an external thread and a nut matched therewith, and the inner end surface of the nut abuts against the end surface of the first support, so as to limit the position of the first support.

[0017] Furthermore, the centers of the end faces at both ends of the central shaft are provided with center holes, which are adapted to the top of an external grinder.

[0018] Beneficial effects of the utility model:

[0019] 1. The utility model limits the workpiece by cooperating with the first support and the limiting mechanism, and the shifting rod and the first support are detachably connected to the central axis, so that the workpiece can be easily installed.

[0020] 2. The limiting mechanism of the utility model can be set as the second support, and the workpiece can be limited by cooperating with the outer circle; after installation, the gap between the outer circle of the first support and the second support and the inner hole of the workpiece is adjusted to make the outer circle jump of the left and right sides of the workpiece meet the target requirements, and then the workpiece is pressed to improve the processing accuracy.

[0021] 3. The limiting mechanism of the utility model can also be set as a variable diameter section, which is limited by the workpiece through the way of tapered surface cooperation; after installation, it is only necessary to adjust the gap between the outer circle of the first support and the inner hole of the workpiece so that the outer circle runout on the left and right sides of the workpiece meets the target requirements, and then the workpiece is clamped to improve the processing accuracy and improve the processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the structure of workpiece positioning in the first embodiment of the utility model;

[0023] Figure 2 It is a structural schematic diagram of the central axis in the first embodiment of the utility model;

[0024] Figure 3 It is a structural schematic diagram of the first support in the first embodiment of the utility model;

[0025] Figure 4 It is a structural schematic diagram of the second support in the first embodiment of the utility model;

[0026] Figure 5 It is a structural schematic diagram of workpiece positioning in the second embodiment of the utility model.

[0027] Description of reference numerals:

[0028] 1- lever, 2- screw, 3- second support, 31- second boss, 4- center axis, 41- reducing section, 42- third boss, 5- first support, 51- first boss, 6- nut, 7- workpiece. DETAILED DESCRIPTION

[0029] Embodiment 1

[0030] The utility model is a fixture for grinding the outer circle of a workpiece, such as Figure 1 As shown, it includes a central shaft 4, a lever 1 and a limiting mechanism arranged at one end of the central shaft 4, and a first support 5 arranged at the other end of the central shaft 4. The lever 1 is located outside the limiting mechanism, arranged along the radial direction of the central shaft 4, and is detachably connected to the central shaft 4. The lever 1 is used to cooperate with the rotating mechanism of the external grinder to drive the central shaft 4 to rotate.

[0031] The first support 5 is a cylindrical structure, such as Figure 3 As shown, the first support 5 is sleeved on the central shaft 4 and is detachably connected to the central shaft 4. A first boss 51 is provided at one end of the outer wall of the first support 5. The limiting mechanism includes a second support 3, which is a cylindrical structure. Figure 4 As shown, the second support 3 is sleeved on one end of the central shaft 4 and is detachably connected to the central shaft 4, and one end of its outer wall is provided with a second boss 31. The second support 3 cooperates with the first support 5 to limit the end of the workpiece 7.

[0032] The central shaft 4 is located between the second support 3 and the lever 1 and a third boss 42 is provided. Figure 1 and Figure 2 As shown, the second boss 31 is arranged close to the third boss 42 and abuts against the inner end surface of the third boss 42. The second boss 31 and the third boss 42 are provided with threaded holes correspondingly, and screws 2 are arranged in the corresponding threaded holes to fix them. The first boss 51 of the first support 5 is arranged close to the other end of the central shaft 4. The other end of the central shaft 4 is provided with an external thread and a nut 6 adapted thereto. The inner end surface of the nut 6 abuts against the end surface of the first support 5, which is used to limit the first support 5.

[0033] Center holes are provided at the center positions of both end faces of the center shaft 4 to facilitate installation with the top of an external grinder or a deflection instrument. To improve installation accuracy, the center hole is preferably a tapered hole.

[0034] In this embodiment, the outer circle positioning is realized by the cooperation of the first support 5 and the second support 3, and the specific setting method is as follows:

[0035] First, the second support 3 is sleeved on the central shaft 4, and the second support 3 and the third boss 42 are fixedly connected by the screw 2 to prevent the two from rotating relative to each other; the workpiece 7 is passed through the central shaft 4, and the end face of one end is against the inner end face of the second boss 31; the first support 5 is sleeved on the other end of the central shaft 4, and the inner end face of the first boss 51 is against the other end face of the workpiece 7, and the nut 6 is pre-tightened; the lever 1 is connected to the central shaft 4 by threading, as shown in FIG. Figure 1 Install the fixture and workpiece 7 together on the deflection instrument or directly on the cylindrical grinder, and use a dial indicator to measure the outer circle runout on both sides of the workpiece 7. Adjust as shown. Figure 1 As shown in the figure, the outer circle runout on the right side is slightly loosened. First, the nut 6 is slightly loosened, and the gap between the inner hole of the right workpiece 7 and the outer circle of the second support 3 is adjusted until the outer circle runout of the workpiece 7 reaches the expected requirement. Then adjust as shown in the figure. Figure 1 The outer circle runout of the workpiece 7 on the left side is adjusted in the same way as on the right side. Adjust the runout on both sides to the appropriate position, tighten the nut 6, and then you can start processing. This adjustment method is suitable for trial production. The outer circle runout can be adjusted at any time, and the runout value can also be adjusted as needed, but the adjustment time is relatively long.

[0036] Embodiment 2

[0037] The difference between this embodiment and the first embodiment lies in the setting of the limiting mechanism. In this embodiment, the limiting mechanism includes a reducing section 41 arranged on the central axis 4, and the reducing section 41 includes a conical section arranged on the outer wall of the central axis 4 and a large diameter section connected thereto, and the large diameter section is located between the conical section and the lever 1; an auxiliary positioning conical surface is pre-processed on the left side of the workpiece 7, and the conical surface and the conical section of the central axis 4 are processed at the same angle, and strict requirements are imposed on their angle and roundness to ensure the matching accuracy between the conical surface and the conical section of the central axis 4; the auxiliary positioning conical surface is located on the inner side of the workpiece 7, the wall thickness is relatively thick, and the deformation is relatively small, so it can be used directly as a reference.

[0038] The fixture of this embodiment realizes the positioning of the workpiece 7 by combining the left conical surface positioning and the right outer circle positioning. Figure 5 As shown, the second support 3 is no longer installed, and the left side of the workpiece 7 is directly installed on the central shaft 4, and the limit is achieved through the tapered surface matching, and the installation method on the right side is the same as in Example 1. In this method, the left side is no longer adjusted, the outer circle runout of the left side of the workpiece 7 is basically fixed, and the adjustment method on the right side is the same as in Example 1. This method is more efficient than Example 1, and the accuracy is slightly worse than that of Example 1, but it can also meet the processing requirements of the workpiece 7, and the processing efficiency is increased by 50% compared with Example 1.

[0039] The above description is only a specific implementation mode of the present utility model, but the protection scope of the present utility model is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or substitutions within the technical scope disclosed in the present utility model, and these modifications or substitutions should be included in the protection scope of the present utility model.

Claims

1. A fixture for grinding the outer circle of a workpiece, characterized in that: It comprises a central shaft (4), a lever (1) and a limiting mechanism arranged at one end of the central shaft (4), and a first support (5) arranged at the other end of the central shaft (4); The first support (5) is a cylindrical structure, sleeved on the central shaft (4), and detachably connected to the central shaft (4); A first boss (51) is provided at one end of the outer side wall of the first support (5); The central axis (4) is inserted into the workpiece (7) to be processed, the limiting mechanism is adapted to the inner hole at one end of the workpiece (7), and the outer circle of the first support (5) is matched to the inner hole at the other end of the workpiece (7); the limiting mechanism and the first support (5) are used to limit the two ends of the workpiece (7); The lever (1) is located outside the limiting mechanism and is arranged along the radial direction of the central shaft (4). It is detachably connected to the central shaft (4). The lever (1) cooperates with the rotating mechanism of the external grinder to drive the central shaft (4) to rotate.

2. A fixture for grinding the outer circle of a workpiece according to claim 1, characterized in that: The limiting mechanism comprises a second support (3); The second support (3) is a cylindrical structure, sleeved on the central shaft (4), and detachably connected to the central shaft (4); A second boss (31) is provided at one end of the outer side wall of the second support (3).

3. A fixture for grinding the outer circle of a workpiece according to claim 2, characterized in that: A third boss (42) is provided on the central axis (4) between the second support (3) and the shifting rod (1); The second boss (31) is arranged close to the third boss (42) and abuts against the inner end surface of the third boss (42); The second boss (31) and the third boss (42) are connected via threads.

4. A fixture for grinding the outer circle of a workpiece according to claim 1, characterized in that: The limiting mechanism comprises a diameter-reducing section (41) arranged on the central shaft (4), the diameter-reducing section (41) comprising a conical section arranged on the outer side wall of the central shaft (4) and a large diameter section connected thereto, the large diameter section being located between the conical section and the shifting rod (1); the conical section cooperates with an auxiliary positioning conical surface at one end of a workpiece (7) to be processed.

5. A fixture for grinding the outer circle of a workpiece according to claim 4, characterized in that: A third boss (42) is arranged on the central shaft (4) between the diameter-changing section (41) and the shifting rod (1).

6. A fixture for grinding the outer circle of a workpiece according to any one of claims 1 to 5, characterized in that: The first boss (51) of the first support (5) is arranged close to the other end of the central axis (4); The other end of the central shaft (4) is provided with an external thread and a nut (6) adapted thereto, and the inner end surface of the nut (6) abuts against the end surface of the first support (5) to limit the position of the first support (5).

7. A fixture for grinding the outer circle of a workpiece according to claim 6, characterized in that: The centers of the end faces at both ends of the central shaft (4) are provided with center holes, which are adapted to the top of an external grinder.

Images