Internal grinding clamp for precisely grinding equally-divided holes of parts

Abstract

The utility model discloses an internal grinding clamp for precisely grinding equally-divided holes of parts, which comprises a connecting flange connected with a headstock of an internal grinding machine, and a positioning shaft and a support are symmetrically mounted on two sides of the front end of the connecting flange; wherein an index plate is installed on the positioning shaft in a locking mode, a pressing assembly for pressing a part to be machined is arranged on the upper portion of the index plate, the supporting axis of the support is perpendicular to the axis of the index plate, a positioning pin is arranged on the supporting axis, the positioning pin is centered with a tooth groove in the index plate, an elastic assembly is arranged on the positioning pin, and the elastic assembly is matched with the tooth groove in the index plate. Balancing weights are symmetrically fixed to the connecting flanges on the two sides of the support, the indexing plate and the positioning pin positioning structure are adopted for clamping a machined part, the indexing precision is improved, the workpiece machining quality is improved, the internal grinding clamp is simple in structural design, the indexing precision is improved, the workpiece machining quality is improved, and the machining efficiency is improved. Therefore, the roundness tolerance of a workpiece machining hole is improved, and the grinding yield of parts with different weights is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of grinding machine tooling fixtures, in particular to an internal grinding fixture for precisely grinding equally divided holes of parts. Background Technique

[0002] With the continuous improvement of the level of the equipment manufacturing industry, the accuracy of equally divided holes on some parts directly affects the performance of the equipment, such as the transmission accuracy and noise of the equipment. At present, there are also many domestic manufacturers of coordinate boring machines and coordinate grinding machines, but the production efficiency of these existing machine tools is low, and the accuracy cannot meet the requirements, resulting in the processing centers produced not meeting the requirements either.

[0003] Existing coordinate grinding machines and high-precision processing centers in production include Moore coordinate grinding machines in the United States, Fellmann processing centers in Switzerland, etc. However, these machine tools are expensive, and the cost for small-batch production parts is too high. In addition, the positioning pins used in the indexing mechanisms of current tooling fixtures are basically cylindrical or conical. The indexing accuracy of this form of positioning pin is low, and it cannot meet the requirements for high precision of equally divided holes on parts. Moreover, it is used on ordinary internal grinding machines, so it is necessary to make improvements. Content of the Utility Model

[0004] Aiming at the above defects or deficiencies, the purpose of the utility model is to provide an internal grinding fixture for precisely grinding equally divided holes of parts.

[0005] To achieve the above purpose, the technical solution of the utility model is as follows:

[0006] An internal grinding fixture for precisely grinding equally divided holes of parts, comprising: a connecting flange connected to the headstock of an internal grinding machine, and a positioning shaft and a support are symmetrically installed on both sides of the front end of the connecting flange; wherein, a dividing plate is locked and installed on the positioning shaft, a pressing assembly for pressing the part to be processed is arranged on the upper part of the dividing plate, and a hole-aligning pin for centering the part to be processed is arranged on the lower part of the dividing plate; the supporting axis of the support is perpendicular to the axis of the dividing plate, and a positioning pin is arranged on the supporting axis, the positioning pin is centered with the tooth grooves on the dividing plate, and an elastic assembly for engaging or disengaging the positioning pin with the tooth grooves of the dividing plate is arranged on the positioning pin, and counterweights are symmetrically fixed on the connecting flange on both sides of the support.

[0007] A sealing cover for covering the dividing plate is arranged on the front end face of the connecting flange, a cushion block that can be movably and sealingly attached to the front end port of the sealing cover is fixedly sleeved on the outer circle of the dividing plate; one end of the positioning pin passes through the sealing cover and is centered with the tooth grooves on the dividing plate.

[0008] The rear end of the sealing cover is fixedly connected to the front end face of the connecting flange by a first screw. Between the outer circle of the rear part of the positioning shaft and the inner circle surface that fits with the rear part of the sealing cover, it is sealed by a first sealing ring. A first oil seal that fits and seals with the front port of the sealing cover is sleeved on the cushion block. A sealing gasket is provided between one end face of the support and the sealing cover and the fitting surface.

[0009] The pressing component includes: a washer fixedly sleeved on the outer circle of the front end of the indexing plate. A plurality of tightening screws are evenly arranged on the circumference of the washer. The tightening screws pass through the washer through threads to press the part to be processed.

[0010] A third precision ball sleeve for supporting the part to be processed is sleeved on the outer circle of the middle part of the indexing plate.

[0011] A first precision ball sleeve and a second precision ball sleeve are arranged on the positioning shaft. The positioning shaft rotatably supports the indexing plate through the first precision ball sleeve and the second precision ball sleeve.

[0012] The front section of the positioning shaft is fixedly installed by a nut. A small washer is provided between the nut and the front end face of the indexing plate. The front port of the inner hole of the indexing plate and the positioning shaft are sealed by a second oil seal.

[0013] The upper part of the positioning pin is supported in the inner hole of the support through a fourth precision ball sleeve. The elastic component is arranged in the middle of the positioning pin.

[0014] The elastic component includes: a spring sleeved on the outer circle of the middle part of the positioning pin. A spacer sleeve is provided between the spring and the inner hole of the support. A gland fixedly connected to the lower end of the support is sleeved on the outer circle of the lower part of the positioning pin. The gland limits the spring and the spacer sleeve in the inner hole of the support. A second sealing ring is used to seal between the gland and the outer circle surface of the positioning pin. The lower end of the positioning pin passes through the gland and extends out of the inner hole of the support and a handle is provided on it.

[0015] The indexing groove of the indexing plate is a V-shaped tooth groove with a preset angle. The positioning surface of the positioning pin is two arc surfaces. During indexing, the indexing plate and the positioning pin are positioned by line contact.

[0016] Compared with the prior art, the beneficial effects of the present utility model are:

[0017] The present utility model provides an internal grinding fixture for precision grinding of equally divided holes of parts. Since an indexing plate and a positioning pin are installed on the connecting flange, the device uses the indexing plate and the positioning pin positioning structure to clamp the part to be processed, improving the indexing accuracy, improving the workpiece processing quality, and making the structure design of the internal grinding fixture simple, improving the indexing accuracy, improving the workpiece processing quality, thereby improving the roundness tolerance of the processed holes of the workpiece and improving the finished product rate of grinding parts with different weights.

[0018] In addition, in the fixture of the present utility model, a dividing plate is rotatably supported on the component positioning shaft through a precision ball bushing. A precision ball bushing for supporting the machined part is sleeved on the outer circle of the middle part of the dividing plate. A positioning pin with an axis perpendicular to the axis of the dividing plate is supported inside the support through a precision ball bushing. The structure of the precision ball bushing is adopted for the rotating parts between components in this fixture to achieve clearance-free fit, ensuring flexible rotation of the fixture. Moreover, the structure of the precision ball bushing is also adopted between the machined part and the fixture to achieve clearance-free fit, improving the positional accuracy of the equally divided holes on the part. Brief Description of the Drawings

[0019] Figure 1 It is a schematic structural diagram of the internal grinding fixture for precisely grinding equally divided holes of parts of the present utility model;

[0020] Figure 2 It is a schematic structural diagram of the dividing plate of the internal grinding fixture for precisely grinding equally divided holes of parts;

[0021] Figure 3 It is a schematic structural diagram of the positioning pin of the dividing plate of the internal grinding fixture for precisely grinding equally divided holes of parts of the present utility model;

[0022] Figure 4 It is a schematic structural diagram of the meshing state of the dividing plate and the positioning pin of the internal grinding fixture for precisely grinding equally divided holes of parts of the present utility model.

[0023] In the figure, 1 - positioning shaft; 2 - connecting flange; 3 - first sealing ring; 4 - first screw; 5 - first precision ball bushing; 6 - dividing plate; 7 - sealing cover; 8 - first oil seal; 9 - spacer block; 10 - machined part; 11 - washer; 12 - clamping screw; 13 - third precision ball bushing; 14 - second precision ball bushing; 15 - second oil seal; 16 - small washer; 17 - nut; 18 - hole-aligning pin; 19 - sealing gasket; 20 - positioning pin; 21 - fourth precision ball bushing; 22 - support; 23 - second screw; 24 - spacer sleeve; 25 - spring; 26 - counterweight; 27 - second sealing ring; 28 - gland; 29 - handle. Detailed Description of the Preferred Embodiment

[0024] The present utility model will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0025] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0026] In the present utility model, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be directly connected or indirectly connected through an intermediate medium, and it can be the connection inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0027] It should be noted that in this article, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation. The element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0028] As Figure 1 shown, the present utility model provides an internal grinding fixture for precision grinding of equally divided holes of parts, including: a connecting flange 2 connected to the headstock of an internal grinding machine, and positioning shafts 1 and supports 22 are symmetrically installed on both sides of the front end of the connecting flange 2; a positioning shaft 1 is fixedly connected to the front end of the connecting flange 2, and the axis of the positioning shaft 1 is parallel and offset from the axis of the connecting flange 2 and is fixed on one side of the axis of the front end of the connecting flange 2. The distance between the axis of the positioning shaft 1 and the axis of the connecting flange 2 forms the dividing circle radius of the equally divided holes on the workpiece 10 to be processed. A support 22 is provided on the other side of the axis of the front end of the connecting flange 2 opposite to the positioning shaft 1. It should be noted that the middle part of the indexing plate 6 can provide a distance for installing two workpieces 10 to be processed axially, so as to improve the processing efficiency. And when two workpieces are processed simultaneously, the equally divided holes of the two workpieces can have a high degree of consistency. Two workpieces can be processed at one time on the internal grinding fixture, which improves the processing efficiency. And when two workpieces are processed simultaneously, the equally divided holes of the two workpieces can have a high degree of consistency.

[0029] Among them, an indexing plate 6 is locked and installed on the positioning shaft 1. A pressing assembly for pressing the workpiece 10 to be machined is arranged on the upper part of the indexing plate 6, and a hole aligning pin 18 for centering the workpiece 10 to be machined is arranged on the lower part of the indexing plate 6; the support axis of the support 22 is perpendicular to the axis of the indexing plate 6, and a positioning pin 20 is arranged on the support axis. The positioning pin 20 is centered with the tooth groove on the indexing plate 6. An elastic assembly for engaging or disengaging the positioning pin 20 with the tooth groove of the indexing plate 6 is arranged on the positioning pin 20. Counterweights 26 are symmetrically fixed on the connecting flanges 2 on both sides of the support 22.

[0030] Preferably, a sealing cover 7 for covering the indexing plate 6 is arranged on the front end face of the connecting flange 2. A spacer block 9 that can be movably and sealingly fitted with the front port of the sealing cover 7 is fixedly sleeved on the outer circle of the indexing plate 6; one end of the positioning pin 20 passes through the sealing cover 7 and is centered with the tooth groove on the indexing plate 6.

[0031] Specifically, the rear end of the sealing cover 7 is fixedly connected to the front end face of the connecting flange 2 by a first screw 4. A first sealing ring 3 is arranged between the outer circle of the rear part of the positioning shaft 1 and the inner circle surface that fits with the rear part of the sealing cover 7. A first oil seal 8 that is sealingly fitted with the front port of the sealing cover 7 is sleeved on the spacer block 9.

[0032] In the utility model, the pressing assembly includes: a washer 11 fixedly sleeved on the outer circle of the front end of the indexing plate 6. A plurality of tightening screws 12 are evenly arranged on the circumference of the washer 11. The tightening screws 12 pass through the washer 11 through threads to press the workpiece 10 to be machined. A third precision ball bushing 13 for supporting the workpiece 10 to be machined is sleeved on the outer circle of the middle part of the indexing plate 6. A first precision ball bushing 5 and a second precision ball bushing 14 are arranged on the positioning shaft 1. The positioning shaft 1 rotatably supports the indexing plate 6 through the first precision ball bushing 5 and the second precision ball bushing 14; the front section of the positioning shaft 1 is fixedly installed by a nut 17. A small washer 16 is arranged between the nut 17 and the front end face of the indexing plate 6. A second oil seal 15 is arranged between the front port of the inner hole of the indexing plate 6 and the positioning shaft 1 for sealing.

[0033] A support 22 is arranged on the other side of the axis opposite to the positioning shaft 1 on the front end of the connecting flange 2. The upper part of the positioning pin 20 is supported in the inner hole of the support 22 through a fourth precision ball bushing 21. The elastic assembly is arranged in the middle of the positioning pin 20. One end face of the support 22 is in contact with the sealing cover 7, and a sealing gasket 19 is arranged between the contact surfaces. One end of the positioning pin 20 passes through the sealing cover 7 and is centered with the tooth groove on the indexing plate 6. An elastic assembly for enabling the positioning pin 20 to axially elastically move to engage or disengage with the tooth groove of the indexing plate 6 is arranged between the positioning pin 20 and the support 22.

[0034] The elastic component includes: a spring 25 sleeved on the outer circle of the middle part of the positioning pin 20. A spacer sleeve 24 is provided between the spring 25 and the inner hole of the support 22. A gland 28 fixedly connected to the lower end of the support 22 is sleeved on the outer circle of the lower part of the positioning pin 20. The gland 28 limits the spring 25 and the spacer sleeve 24 in the inner hole of the support 22. A second sealing ring 27 is used for sealing between the gland 28 and the outer circle surface of the positioning pin 20. The lower end of the positioning pin 20 passes through the gland 28 and extends out of the inner hole of the support 22, and a handle 29 is provided at the extending end.

[0035] In the present utility model, counterweights 26 are symmetrically fixed on the connecting flanges 2 on both sides of the support 22. The counterweights 26 are fixedly connected to the connecting flanges 2 by second screws 23. The counterweights 26 improve the roundness tolerance of the machined holes of the workpiece and ensure the grinding of parts with different weights.

[0036] As Figures 2 - 4 shown, in the present utility model, in order to improve the positioning accuracy of the indexing plate 6, the high-precision indexing principle and structure of the mechanical indexing of the indexing plate of the butterfly grinding wheel gear grinding machine are adopted. The indexing groove of the indexing plate 6 is a V-shaped tooth groove with a preset angle, and the positioning surface of the positioning pin 20 is two arc surfaces. During indexing, the indexing plate 6 and the positioning pin 20 are positioned by line contact, so that the positioning accuracy is high.

[0037] As Figure 1 shown, the assembly process of the internal grinding fixture for precision grinding of equally divided holes of parts in the present utility model is as follows:

[0038] After the first sealing ring 3 is sleeved into the sealing groove on the outer circle of the rear part of the positioning shaft 1, the positioning shaft 1 is connected to the connecting flange 2 with screws;

[0039] The sealing cover 7 is connected to the connecting flange 2 with the first screw 4, and the first precision ball sleeve 5, the second precision ball sleeve 14 and the second oil seal 15 are installed on the positioning shaft 1;

[0040] Then the indexing plate 6 is sleeved on the positioning shaft 1. After the spacer sleeve 24, the fourth precision ball sleeve 21 and the spring 25 are installed in the inner hole of the support 22, the positioning pin 20 is inserted;

[0041] Then the second sealing ring 27 is installed in the inner hole of the gland 28. The gland 28 is sleeved on the positioning pin 20, and the gland 28 is connected to the support 22 with screws. Then the handle 29 is locked to the lower end of the positioning pin 20 with a nut;

[0042] A sealing gasket 19 is installed between the sealing cover 7 and the support 22. After the positioning pin 20 and the tooth groove of the indexing plate 6 are aligned, the support 22 is tightened on the connecting flange 2 with screws. After the first oil seal 8 is installed in the spacer block 9, the spacer block 9 is connected to the indexing plate 6 with screws. The counterweights 26 are connected to the connecting flanges 2 on both sides of the support 22 with the second screws 23.

[0043] After the above-mentioned tooling parts are assembled, connect the connecting flange 2 to the internal grinding headstock with screws, and finely adjust the connecting flange 2 to make it concentric with the internal grinding headstock. Slip the third precision ball bushing 13 onto the indexing plate 6, place two workpieces 10 to be machined on the third precision ball bushing 13, align the workpieces 10 to be machined with the hole alignment pin 18, clamp the workpieces 10 to be machined with the clamping screw 12, and lock the nut 17, then machining can be carried out.

[0044] After a set of holes are machined, loosen the nut 17, pull down the positioning pin 20, rotate the indexing plate 6 to move the workpiece 10 to the next set of equally spaced holes. The positioning pin 20 moves upward under the action of the spring 25 and engages with the tooth groove of the indexing plate 6. After locking the nut 17, continue the machining.

[0045] In the present utility model, the indexing plate 6 and the positioning pin 20 positioning structure are adopted to clamp the workpiece 10 to be machined, which improves the indexing accuracy, improves the machining quality of the workpiece, and simplifies the structural design of the internal grinding fixture. Moreover, in the present utility model, the structure of the precision ball bushing is adopted for the rotating parts between components to achieve clearance-free fit, ensuring flexible rotation of the fixture. The structure of the precision ball bushing is also adopted between the workpiece to be machined and the fixture to achieve clearance-free fit, improving the positional accuracy of the equally spaced holes on the part.

[0046] It should be noted that the rear end of a certain component described in the present utility model refers to the left side of the component in the attached drawings. On the contrary, the front end refers to the right side of the component in the attached drawings. The description of this positional relationship is based on the orientation or positional relationship shown in the attached drawings, only for the convenience of describing the present utility model and simplifying the description. Therefore, it should not be construed as a limitation to the present utility model.

[0047] For those skilled in the art, it is obvious that the present utility model is not limited to the details of the above-mentioned exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present utility model. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present utility model is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present utility model. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0048] For those skilled in the art, it is obvious that the above specific factual examples are only the preferred solutions of the present utility model. Therefore, the improvements and changes that those skilled in the art may make to some parts of the present utility model still embody the principle of the present utility model and achieve the purpose of the present utility model, and all belong to the scope protected by the present utility model.

Claims

1. An internal grinding fixture for precision grinding of equally divided holes of parts, characterized in that: include: A connecting flange (2) connected to a headstock of an internal cylindrical grinding machine, wherein a positioning shaft (1) and a support (22) are symmetrically mounted on both sides of the front end of the connecting flange (2); wherein a dividing plate (6) is locked and mounted on the positioning shaft (1), a clamping assembly for clamping a machined part (10) is disposed on the upper portion of the dividing plate (6), and a hole plug (18) for centering the machined part (10) is disposed on the lower portion of the dividing plate (6); the supporting axis of the support (22) is perpendicular to the axis of the dividing plate (6), and a positioning pin (20) is disposed on the supporting axis, the positioning pin (20) is aligned with a tooth groove on the dividing plate (6), and an elastic assembly is disposed on the positioning pin (20) for engaging or disengaging the positioning pin (20) with the tooth groove of the dividing plate (6), and counterweights (26) are symmetrically fixed on the connecting flanges (2) on both sides of the support (22).

2. The internal grinding fixture for precision grinding of equally divided holes of parts according to claim 1 is characterized in that: A sealing cover (7) for covering the indexing plate (6) is provided on the front end surface of the connecting flange (2); a cushion block (9) is fixedly sleeved on the outer circle of the indexing plate (6) and is movably sealed with the front end of the sealing cover (7); one end of the positioning pin (20) passes through the sealing cover (7) and is aligned with the tooth groove on the indexing plate (6).

3. The internal grinding fixture for precision grinding of equally divided holes of parts according to claim 2 is characterized in that: The rear end of the sealing cover (7) is fixedly connected to the front end face of the connecting flange (2) by means of a first screw (4); the outer circle of the rear part of the positioning shaft (1) is in contact with the inner circle of the rear part of the sealing cover (7) and is sealed by means of a first sealing ring (3); the cushion block (9) is sleeved with a first oil seal (8) which is in contact with the front end of the sealing cover (7); one end face of the support (22) is in contact with the sealing cover (7) and a sealing gasket (19) is provided between the contacting surfaces.

4. The internal grinding fixture for precision grinding of equally divided holes of parts according to claim 1 or 2, characterized in that: The clamping assembly comprises: a washer (11) fixedly sleeved on the outer circle of the front end of the indexing plate (6); a plurality of tightening screws (12) are evenly arranged on the circumference of the washer (11); the tightening screws (12) and the washer (11) penetrate the washer (11) via threads to tighten the processed part (10).

5. The internal grinding fixture for precision grinding of equally divided holes of parts according to claim 1, characterized in that: A third bead sleeve (13) for supporting the processed part (10) is sleeved on the outer circle of the middle part of the indexing plate (6).

6. The internal grinding fixture for precision grinding of equally divided holes of parts according to claim 1, characterized in that: The positioning shaft (1) is provided with a first bead sleeve (5) and a second bead sleeve (14), and the positioning shaft (1) rotatably supports the indexing plate (6) through the first bead sleeve (5) and the second bead sleeve (14).

7. The internal grinding fixture for precision grinding of equally divided holes of parts according to claim 1 or 6, characterized in that: The front section of the positioning shaft (1) is fixedly installed by a nut (17), and a small washer (16) is provided between the nut (17) and the front end surface of the indexing plate (6); the front end of the inner hole of the indexing plate (6) and the positioning shaft (1) are sealed by a second oil seal (15).

8. The internal grinding fixture for precision grinding of equally divided holes of parts according to claim 1, characterized in that: The upper part of the positioning pin (20) is supported in the inner hole of the support (22) through a fourth bead sleeve (21), and the elastic component is arranged in the middle part of the positioning pin (20).

9. The internal grinding fixture for precision grinding of equally divided holes of parts according to claim 1, characterized in that: The elastic component comprises: a spring (25) sleeved on the outer circle of the middle part of the positioning pin (20); a spacer sleeve (24) is provided between the spring (25) and the inner hole of the support (22); a pressure cover (28) fixedly connected to the lower end of the support (22) is sleeved on the outer circle of the lower part of the positioning pin (20); the pressure cover (28) limits the spring (25) and the spacer sleeve (24) in the inner hole of the support (22); the pressure cover (28) and the outer circle surface of the positioning pin (20) are sealed by a second sealing ring (27); the lower end of the positioning pin (20) passes through the pressure cover (28) and extends out of the inner hole of the support (22) and is provided with a handle (29).

10. The internal grinding fixture for precision grinding of equally divided holes of parts according to claim 1, characterized in that: The indexing groove of the indexing plate (6) is a V-shaped tooth groove with a preset angle, and the positioning surface of the positioning pin (20) is two arc surfaces. During indexing, the indexing plate (6) and the positioning pin (20) are positioned through line contact.

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