Off-center grinding fixture and grinding machine

Abstract

The utility model discloses an eccentric grinding clamp and grinding machine bed. The eccentric grinding clamp includes the reference plate subassembly for bearing the workpiece with eccentric pin hole to be processed, the centring subassembly and first drive part set up in reference plate subassembly, first drive part is connected with centring subassembly, and the centring subassembly includes the centring pin, and first drive part is used for driving centring pin alignment to pass through the pin hole of workpiece to be processed to make centring pin and pin hole axis coincide. The utility model clamp is accurate control the motion trail of centring pin through first drive part, ensures that centring pin and workpiece eccentric pin hole's axis alignment, thereby solves the technical problem that present clamp can not locate eccentric pin hole accurately, and effectively promotes eccentric pin hole grinding processing's coaxial degree precision.

Description

Technical Field

[0001] This utility model relates to the field of machining technology, and in particular to an eccentric grinding fixture and a grinding machine tool. Background Technology

[0002] In the machining of compressor lower flange workpieces, the pin hole is an eccentric machining process, with the center not at the workpiece center and the workpiece having a non-circular shape. Existing machine tool clamps cannot directly clamp such workpieces due to structural limitations. Furthermore, this pin hole machining is a precision eccentric grinding process, requiring high machining accuracy. However, existing grinding fixtures suffer from problems such as inability to correctly align the workpiece pin hole and ineffective workpiece clamping, resulting in low machining efficiency and difficulty in guaranteeing accuracy. Therefore, there is an urgent need to design a specialized eccentric clamping fixture to solve the aforementioned clamping and machining accuracy problems. Utility Model Content

[0003] The present invention provides an eccentric grinding fixture and a grinding machine tool, which aims to solve the problem that it is difficult to accurately position the eccentric pin hole of the lower flange of the existing compressor, thus affecting the coaxiality accuracy of the machining.

[0004] This utility model provides an eccentric grinding fixture, comprising: a reference plate assembly for carrying a workpiece to be processed with an eccentric pin hole, a centering assembly disposed on the reference plate assembly, and a first driving member, wherein the first driving member is connected to the centering assembly, the centering assembly includes a centering pin, and the first driving member is used to drive the centering pin to align with the pin hole passing through the workpiece to be processed so that the centering pin coincides with the axis of the pin hole.

[0005] Furthermore, the reference plate assembly includes a reference plate, and the centering assembly further includes a guide sleeve disposed on the reference plate. The guide sleeve has a guide hole, one end of the centering pin passes through the guide hole, and the other end is used to connect with the first driving member. The first driving member is used to drive the centering pin to move axially along the guide hole.

[0006] Furthermore, the centering component also includes a limiting post and a mounting base. The other end of the centering pin is provided with a fixed end, and the fixed end of the centering pin passes through the limiting post. The limiting post is fixedly connected to the top of the mounting base, and the bottom of the mounting base is connected to the first driving member. The upper end face of the fixed end is horizontally attached to the top surface of the inner wall of the limiting post, and the lower end face is horizontally attached to the top end face of the mounting base.

[0007] Furthermore, the centering assembly also includes at least two positioning pins, which are disposed on the reference plate assembly and are used for alignment with positioning holes passing through the workpiece to be processed.

[0008] Furthermore, the eccentric grinding fixture also includes a clamping mechanism and a second driving member. The clamping mechanism is disposed on the reference plate assembly, and the second driving member is used to drive the clamping mechanism to clamp or release the workpiece to be processed.

[0009] Furthermore, the clamping mechanism includes a chuck assembly, a claw assembly and a lever fastening assembly disposed on the chuck assembly. The chuck assembly is fixedly connected to the reference plate assembly. The second driving member is used to drive the claw assembly to move toward or away from the workpiece to clamp or release the workpiece. The lever fastening assembly is used for transmission engagement with the claw assembly to drive it to rotate during movement.

[0010] Furthermore, the chuck assembly includes a chuck and a chuck base. The chuck is fixedly connected to the reference plate assembly, and a plurality of the pull claw assemblies are rotatably connected to the chuck base through the chuck. The chuck base is connected to the second drive member.

[0011] Furthermore, the chuck assembly also includes a chuck bushing, the chuck seat has a shaft hole, the chuck bushing is fixed in the shaft hole, the chuck bushing is fixedly connected to the second drive member, and the centering component passes through the chuck bushing.

[0012] Furthermore, the pull claw assembly includes a pull claw and a drive shaft fixedly connected to the pull claw. A guide groove is provided on the shaft body, and the guide groove extends along the axial and circumferential directions of the drive shaft. The pull rod fastening assembly includes a fastening pin, which slides with the guide groove to drive the pull claw to rotate and lift.

[0013] Furthermore, the puller assembly also includes a pad, which is detachably mounted on the side of the puller facing the workpiece to be processed.

[0014] Furthermore, the reference plate assembly includes a reference plate, a reference fixing plate, and a reference mounting plate. The reference plate is fixed on the reference fixing plate, the reference fixing plate is fixed on the reference mounting plate, and the reference mounting plate is fixed on the chuck assembly.

[0015] Furthermore, the pull claw assembly is provided in three parts, and the reference plate assembly further includes a counterweight and an adjustment block. The adjustment block is detachably fixed on the counterweight and the counterweight is fixed on the reference plate. One of the pull claw assemblies is used to clamp the adjustment block, and the other two pull claw assemblies are used to clamp the workpiece to be processed.

[0016] Furthermore, the reference plate is provided with multiple steps for supporting the workpiece to be processed, and each step has a wear-resistant body on its upper surface, and each wear-resistant body is of equal height.

[0017] Furthermore, the edge of the reference fixing plate is provided with multiple arc-shaped notches to avoid the movement of the pull claw assembly.

[0018] This utility model also provides a grinding machine tool, including the above-mentioned eccentric grinding fixture.

[0019] This invention provides an eccentric grinding fixture and a grinding machine tool. The eccentric grinding fixture includes a reference plate assembly, a centering assembly, and a first driving member. The reference plate assembly supports the workpiece to be processed, which has an eccentric pin hole. The centering assembly is mounted on the reference plate assembly and includes a centering pin. The first driving member is connected to the centering assembly and drives the centering pin to align with the pin hole passing through the workpiece, so that the axis of the centering pin coincides with the axis of the pin hole. This fixture precisely controls the movement trajectory of the centering pin through the first driving member, ensuring that the axis of the centering pin is strictly aligned with the axis of the eccentric pin hole on the workpiece. This solves the technical problem that existing fixtures cannot accurately position eccentric pin holes, effectively improving the coaxiality accuracy and clamping efficiency of eccentric pin hole grinding. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a cross-sectional schematic diagram of the eccentric grinding fixture according to an embodiment of the present utility model;

[0022] Figure 2 This is a schematic diagram of the first and second driving components of the eccentric grinding fixture according to an embodiment of the present utility model;

[0023] Figure 3 This is a schematic diagram of the workpiece to be processed according to an embodiment of the present utility model;

[0024] Figure 4a This is a schematic diagram of the centering component of the eccentric grinding fixture according to an embodiment of the present utility model;

[0025] Figure 4b This is a schematic diagram of the centering pin of the centering assembly of the eccentric grinding fixture according to an embodiment of the present utility model;

[0026] Figure 4c This is a schematic diagram of the limiting post of the centering component of the eccentric grinding fixture according to an embodiment of the present utility model;

[0027] Figure 5 This is a three-dimensional schematic diagram of the eccentric grinding fixture according to an embodiment of the present utility model;

[0028] Figure 6This is an exploded view of the eccentric grinding fixture according to an embodiment of the present invention;

[0029] Figure 7a This is another perspective view of the eccentric grinding fixture according to an embodiment of the present utility model;

[0030] Figure 7b This is a top view schematic diagram of the eccentric grinding fixture according to an embodiment of the present utility model;

[0031] Figure 8a This is a schematic diagram of the pull claw assembly of the eccentric grinding fixture according to an embodiment of the present invention;

[0032] Figure 8b This is an exploded view of the puller assembly of the eccentric grinding fixture according to an embodiment of the present invention;

[0033] Figure 8c This is a schematic diagram of the claw fixing shaft of the claw assembly of the eccentric grinding fixture in an embodiment of this utility model;

[0034] Figure 9 This is a schematic diagram of the drive shaft of the pull claw assembly of the eccentric grinding fixture in an embodiment of this utility model;

[0035] Figure 10 for Figure 1 Enlarged view of part A;

[0036] Figure 11a This is a schematic diagram of the clamping mechanism of the eccentric grinding fixture according to an embodiment of the present utility model;

[0037] Figure 11b This is another schematic diagram of the clamping mechanism of the eccentric grinding fixture according to an embodiment of the present utility model;

[0038] Figure 11c This is a schematic diagram of the chuck bushing of the eccentric grinding fixture according to an embodiment of the present utility model;

[0039] Figure 12a This is a schematic diagram of the chuck base plate cover of the eccentric grinding fixture according to an embodiment of the present utility model;

[0040] Figure 12b This is a schematic diagram of the chuck base plate of the eccentric grinding fixture according to an embodiment of the present utility model;

[0041] Figure 12c This is a schematic diagram of the chuck seat of the eccentric grinding fixture according to an embodiment of the present utility model;

[0042] Figure 12d This is another schematic diagram of the chuck seat of the eccentric grinding fixture according to an embodiment of the present utility model;

[0043] Figure 12e This is a schematic diagram of the chuck of the eccentric grinding fixture according to an embodiment of the present invention;

[0044] Figure 13 This is a schematic diagram of the reference plate of the eccentric grinding fixture in an embodiment of this utility model;

[0045] Figure 14 This is a schematic diagram of the tie rod fastening assembly of the eccentric grinding fixture according to an embodiment of the present utility model; Attached image description:

[0047] 101. Mounting base; 102. Fixing screw; 103. Bushing nut; 104. Chuck bushing; 105. Fixing screw; 106. Fixing screw; 107. Chuck seat; 108. Chuck base plate; 109. Chuck base plate cover; 110. Fixing screw; 111. Centering pin; 112. Reference mounting plate; 113. Limiting pin; 114. Fixing screw; 115. Fixing screw; 116. Reference fixing plate; 117. Reference plate; 118. Adjusting block; 119. Counterweight block; 120. Fixing nut; 126. Locating pin; 127. Fixing screw; 128. Guide sleeve; 250. Pull claw assembly A; 251. Pull claw assembly B; 252. Pull claw assembly C; 140. Drive shaft; 141. Internal grinding shaft sleeve seat; 142. Adjusting support plate; 143. Snap ring; 144. Shaft pin; 145. Pull claw fixing shaft; 146. Fixing screw; 147. Pad; 1 48. Pull claw; 149. Fixing screw; 150. Fixing screw; 151. Fixing screw; 152. Floating connecting block; 153. Fixing nut; 154. Fixing screw; 300. Pull rod fastening assembly; 301. Sealing nut; 302. Snap ring; 303. Fastening pin; 304. Needle roller radial bearing; 305. Locking nut; 306. Threaded sleeve; 181. Guide groove; 182. Step; 183. Internal thread; 800 184. Yield arc; 185. Triangular yield arc; 186. Through hole; 187. Frustum; 188. Wear-resistant body; 189. Internal thread of chuck bushing; 190. Limiting ring groove of chuck bushing; 191. Limiting step of chuck bushing; 192. Inner circle of chuck seat; 193. External thread of mounting seat; 200. Workpiece to be processed; 201. Pin hole; 510. First driving component; 511. Second driving component; 700. Clamping mechanism; 750. Centering assembly. Detailed Implementation

[0048] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0049] The directional terms used in this invention, such as "up," "down," "front," "back," "left," "right," "inner," "outer," and "side," are merely for reference to the accompanying drawings. Therefore, the directional terms used are for explanation and understanding of this invention, and not for limiting it. Furthermore, in the accompanying drawings, structures that are similar or identical are indicated by the same reference numerals.

[0050] It should be noted that the connection mentioned in this utility model can be a direct connection or an indirect connection, and no limitation is made here.

[0051] In the field of compressor manufacturing, the machining of eccentric pin holes in lower flange workpieces is difficult due to the fact that the center of the pin hole is off from the center of the workpiece and the workpiece is a non-circular structure. This makes it difficult for existing grinding fixtures to accurately position the workpiece, often resulting in problems such as unstable clamping and large coaxiality deviation. This seriously affects the machining accuracy of the pin hole and the subsequent assembly quality. There is an urgent need to design a special fixture to solve the positioning problem of this type of eccentric grinding.

[0052] Please see Figures 1 to 14 , Figure 1 An eccentric grinding fixture proposed in this utility model embodiment includes: a reference plate assembly for carrying a workpiece 200 to be processed with an eccentric pin hole 201, a centering assembly 750 disposed on the reference plate assembly, and a first driving member 510. The first driving member 510 is connected to the centering assembly 750. The centering assembly 750 includes a centering pin 111. The first driving member 510 is used to drive the centering pin 111 to align with the pin hole 201 passing through the workpiece 200 to make the axis of the centering pin 111 coincide with that of the pin hole 201.

[0053] Reference Figure 1-3 Specifically, the reference plate assembly includes a reference plate 117, the surface of which has holes for centering. A centering assembly 750 is disposed below the reference plate 117 and includes a centering pin 111 connected to a first driving member 510, which drives the centering pin 111 to reciprocate axially. The workpiece 200 to be processed is a non-circular structure (e.g., a compressor lower flange, a non-circular structure with an eccentric pin hole 201; it is understood that it could also be other similar structures), with the center of its eccentric pin hole 201 offset from the workpiece center. When the workpiece is placed on the upper surface of the reference plate 117, the centering pin 111, under the action of the first driving member 510, passes through the holes in the reference plate 117 from bottom to top and is precisely inserted into the workpiece pin hole 201. Since the axis of the grinding wheel of the grinding machine tool has been pre-calibrated and aligned with the axis of the centering pin 111, when the centering pin 111 is inserted into the pin hole 201, the position of the pin hole 201 can be forcibly corrected, so that the axis of the pin hole 201 is coaxial with the axis of the centering pin 111, thereby achieving precise alignment between the axis of the grinding wheel and the axis of the pin hole 201, and ultimately ensuring the coaxiality accuracy of the pin hole 201 during grinding.

[0054] In this embodiment, the first driving member 510 can drive the centering pin 111 to align with the pin hole 201 passing through the workpiece 200 to be processed, so that the centering pin 111 and the pin hole 201 coincide on the axis, thereby achieving precise positioning of the eccentric pin hole 201 of the workpiece 200 to be processed, providing an accurate reference for subsequent grinding processing, solving the problems of difficult positioning and ineffective clamping of existing fixtures when processing the eccentric pin hole 201 of non-circular workpieces, and ensuring the coaxiality and accuracy requirements of the grinding processing of the eccentric pin hole 201.

[0055] Reference Figure 4a In one embodiment, the centering assembly 750 further includes a guide sleeve 128 disposed on the reference plate assembly. The guide sleeve 128 has a guide hole, one end of the centering pin 111 passes through the guide hole, and the other end is used to connect with the first driving member 510. The first driving member 510 is used to drive the centering pin 111 to move axially along the guide hole. Specifically, the guide sleeve 128 is fixed in a hole in the reference plate 117 by screws, and its center has a guide hole extending vertically. One end of the centering pin 111 passes through the guide hole and can move axially along the guide hole, and the other end is connected to the first driving member 510 (such as a hydraulic cylinder, pneumatic cylinder, or motor, etc., the specific type is not limited). The guide hole plays a guiding role for the centering pin 111, ensuring that when the centering pin 111 moves vertically up and down under the drive of the first driving component 510, its axis always coincides with the axis of the guide hole, avoiding deviation during the movement, thereby ensuring that the centering pin 111 can accurately pass through the workpiece pin hole 201 and achieve precise centering of the pin hole 201.

[0056] Reference Figures 4a-4c and Figure 1In this embodiment, the centering component 750 further includes a limiting post 113 and a mounting base 101. The other end of the centering pin 111 is provided with a fixed end, which passes through the limiting post 113. The limiting post 113 is fixedly connected to the top of the mounting base 101, and the bottom of the mounting base 101 is connected to the first driving member 510. The upper end face of the fixed end is horizontally abutted against the top surface of the inner wall of the limiting post 113, and the lower end face is horizontally abutted against the top surface of the mounting base 101. Specifically, the limiting post 113 of the centering component 750 has a hollow structure and a through hole at the top. The fixed end of the centering pin 111 is T-shaped, with its rod passing through the through hole of the limiting post 113, and the T-shaped horizontal end remaining in the cavity between the limiting post 113 and the top of the mounting base 101. The limiting post 113 is fixedly connected to the top of the mounting base 101 by threads, forming a closed inner cavity. The upper end face of the fixed end is horizontally attached to the top surface of the inner wall of the limiting post 113, and the lower end face is horizontally attached to the top end face of the mounting base 101, thereby limiting the axial position of the centering pin 111 and ensuring its verticality. The axes of the limiting post 113, the mounting base 101, and the centering pin 111 are in the same direction and coincide. The bottom of the mounting base 101 is provided with an external thread, which is connected to the top of the piston rod of the first driving member 510 (such as a hydraulic cylinder) through the thread. When the first driving member 510 drives the mounting base 101, on the one hand, the driving force of the first driving member 510 causes the movement range of the centering pin 111 to always remain within the center diameter of the guide hole of the guide sleeve 128, which can drive the centering pin 111 to move axially. The guide sleeve 128 prevents the centering pin 111 from tilting or shifting. On the other hand, the fitting structure between the T-shaped fixed end and the inner cavity is used to straighten the centering pin 111, further preventing the centering pin 111 from tilting or shifting. The entire centering assembly 750, through the coaxial series structure of the limiting post 113, the mounting base 101 and the centering pin 111, constructs a rigid force transmission chain from the first driving member 510 to the centering pin 111. This not only ensures the effective transmission of driving force, but also eliminates the risk of swaying during the movement of the centering pin 111 through the precise cooperation between the T-shaped fixed end and the limiting structure, providing a reliable axial positioning reference for the precise alignment of the eccentric pin hole 201.

[0057] Reference Figure 5In this embodiment, the centering component 750 further includes at least two locating pins 126, which are disposed on the reference plate assembly and used for alignment with the locating holes passing through the workpiece 200 to be processed. Specifically, the upper surface of the reference plate 117 is provided with at least two threaded locating pins 126, which are precisely aligned with the pre-set locating holes on the workpiece 200 to be processed. During the clamping process, the operator only needs to align the locating hole of the workpiece with the locating pins 126 on the reference plate 117 to achieve rapid pre-positioning of the workpiece, significantly improving clamping efficiency. This double locating pin 126 structure not only establishes an initial reference for the precise alignment of the subsequent centering pins 111, but also effectively restricts the workpiece's degree of freedom in the horizontal plane, preventing displacement during processing and providing a reliable positioning basis to ensure the final grinding accuracy.

[0058] Reference Figure 7a and Figure 7b In one embodiment, the eccentric grinding fixture further includes a clamping mechanism 700 and a second driving member 511. The clamping mechanism 700 is disposed on the reference plate assembly, and the second driving member 511 is used to drive the clamping mechanism 700 to clamp or release the workpiece 200 to be processed. Specifically, the eccentric grinding fixture further includes a clamping mechanism 700 disposed on the reference plate assembly and a second driving member 511 connected to the clamping mechanism 700. The second driving member 511 drives the clamping mechanism 700 to reliably clamp or quickly release the workpiece 200 to be processed. After the workpiece 200 to be processed is positioned by the centering assembly 750, the second driving member 511 drives the clamping mechanism 700 to operate, firmly clamping the workpiece on the upper surface of the reference plate 117, ensuring that the workpiece remains fixed during the grinding process. After processing is completed, the second driving member 511 drives the clamping mechanism 700 to release the workpiece for workpiece loading and unloading.

[0059] In this embodiment, the clamping mechanism 700 includes a chuck assembly, a claw assembly, and a lever fastening assembly 300 disposed on the chuck assembly. The chuck assembly is fixedly connected to the reference plate assembly. The second driving member 511 drives the claw assembly to move toward or away from the workpiece 200 to clamp or release the workpiece 200. The lever fastening assembly 300 is used to drive the claw assembly to rotate during movement. Specifically, the clamping mechanism 700 includes a chuck assembly fixedly mounted on the reference plate assembly, on which a claw assembly and a lever fastening assembly 300 are disposed. The second driving member 511 drives the chuck assembly to move the claw assembly vertically, thereby clamping or releasing the workpiece 200. The pull rod fastening assembly 300 and the claw assembly employ a synchronous rotation transmission mechanism, enabling the claw assembly to rotate while moving vertically. This composite motion ensures uniform distribution of clamping force and adapts to the clamping requirements of workpieces with different shapes. It should be noted that this transmission mechanism can be of various forms, as long as it rotates synchronously during movement; no limitation is imposed here. This structure achieves automatic control of the clamping action through mechanical linkage. Combined with the precise positioning function of the centering assembly 750, it significantly improves the machining accuracy and clamping efficiency of eccentric workpieces, while ensuring the stability and reliability of the clamping process.

[0060] In a specific embodiment, the chuck assembly includes a chuck and a chuck base 107. The chuck is fixedly connected to the reference plate assembly, and a plurality of pull claw assemblies are rotatably connected to the chuck base 107 through the chuck. The chuck base 107 is connected to the second drive member 511. Specifically, the chuck assembly includes a chuck formed by combining a chuck base plate 108 and a chuck base plate cover 109 with fixing screws, and a chuck base 107 that cooperates with the chuck, located below the chuck. The chuck base plate cover 109 is fixedly connected to the reference mounting plate 112 of the reference plate assembly with fixing screws. The outer contour of the chuck is larger than that of the reference mounting part. Three pull claw assemblies, A250, B251, and C252, are evenly distributed circumferentially on the chuck base plate cover 109. Each pull claw assembly includes a drive shaft 140. The drive shafts 140 of the multiple pull claw assemblies pass through through holes in the chuck base plate cover 109 and are rotatably connected to the chuck seat 107 via fixing nuts 120. The chuck seat 107 is connected to a second drive member 511, which drives the chuck seat 107 to reciprocate vertically, causing the multiple pull claw assemblies to move closer to or away from the workpiece 200. The second drive member 511 can be, for example, a hydraulic cylinder, a pneumatic cylinder, or a motor, etc., and is not limited here. When the second drive unit 511 drives the chuck base 107 to reciprocate, the chuck base 107 drives multiple pull claw assemblies to move together. Through the transmission cooperation between the pull claw assemblies and the pull rod fastening assembly 300, the pull claw assemblies can be rotated, causing them to rotate as they move towards or away from the workpiece 200 to complete the clamping or releasing action. By providing stable motion guidance for multiple pull claw assemblies through a single chuck base 107, this modular design ensures the synchronous movement accuracy of multiple pull claws 148 and facilitates maintenance and replacement. Combined with the precise control of the second drive unit 511, efficient and stable clamping of eccentric workpieces is achieved.

[0061] Reference Figure 8a and Figure 10Furthermore, the pull claw assembly includes a pull claw 148 and a drive shaft 140 fixedly connected to the pull claw 148. A guide groove 181 is formed on the shaft of the drive shaft 140, extending axially and circumferentially along the drive shaft 140. The pull rod fastening assembly 300 includes a fastening pin 303, which slides with the guide groove 181 to drive the pull claw 148 to rotate and rise. Specifically, the pull claw assembly includes a pull claw 148 and a drive shaft 140 fixedly connected to it. The drive shaft 140 has a guide groove 181 extending axially and circumferentially, such as a spiral or S-shaped groove. It is understood that other shapes of grooves are also possible, as long as they can drive the drive shaft 140 to rotate; no limitation is made here. The pull claw assembly also includes an inner grinding shaft sleeve 141, which is fixed to the chuck base plate cover 109, and the drive shaft 140 passes through the inner grinding shaft sleeve 141. The pull rod fastening assembly 300 includes a fastening pin 303, and the radial side wall of the inner grinding shaft sleeve 141 has a mounting hole through which the pull rod fastening assembly 300 is fixed to the inner grinding shaft sleeve 141. The end of the fastening pin 303 of the pull rod fastening assembly 300 extends radially into the inner grinding shaft sleeve 141 through the mounting hole, and its end slides into the guide groove 181 of the drive shaft 140. When the second driving member 511 drives the claw assembly to move axially, the transmission shaft 140 moves along the axial trajectory of the guide groove 181. Simultaneously, due to the circumferential extension characteristic of the guide groove 181, the fastening pin 303 forces the transmission shaft 140 to rotate around its axis. This allows the claw 148 to rotate and lift with the transmission shaft 140, enabling it to clamp the workpiece at a specific angle when close to it or release it when moving away. The rotary lifting clamping mechanism of this embodiment can automatically adapt to the clamping requirements of workpieces of different shapes, significantly improving the positioning accuracy, clamping stability, and reliability of eccentric workpiece machining.

[0062] Reference Figure 8b In one embodiment, the claw assembly further includes a pad 147, which is detachably mounted on the side of the claw 148 facing the workpiece 200. Specifically, the claw assembly includes a pad 147, which is detachably mounted on the side of the claw 148 facing the workpiece 200 by fixing screws. The pad 147 is used to clamp the upper surface of the workpiece 200. When the workpiece 200 has different thicknesses, the appropriate clamping distance between the claw 148 and the workpiece can be maintained by replacing the pad 147 with one of different thicknesses, thereby adapting to workpieces of different thicknesses, ensuring that the clamping mechanism 700 can effectively clamp workpieces of different thicknesses, and improving versatility and adaptability.

[0063] In one embodiment, the reference plate assembly includes a reference plate 117, a reference fixing plate 116, and a reference mounting plate 112. The reference plate 117 is fixed to the reference fixing plate 116, the reference fixing plate 116 is fixed to the reference mounting plate 112, and the reference mounting plate 112 is fixed to the chuck assembly. Specifically, the reference plate assembly adopts a layered structure, consisting of a reference plate 117, a reference fixing plate 116, and a reference mounting plate 112 from top to bottom. The reference plate 117 is fixed to the upper surface of the reference fixing plate 116 with screws, the reference fixing plate 116 is fixed to the reference mounting plate 112 with screws, and the reference mounting plate 112 is integrally fixed to the top of the chuck assembly. The rigid connection between the layers ensures the stability of the overall structure, effectively suppresses the influence of machining vibration on accuracy, provides a reliable positioning reference for the precision grinding of the eccentric pin hole 201, and significantly improves the versatility and machining accuracy of the fixture.

[0064] Reference Figure 5 In one embodiment, the pull claw assembly has three parts, and the reference plate assembly further includes a counterweight 119 and an adjusting block 118. The adjusting block 118 is detachably fixed to the counterweight 119, and the counterweight 119 is fixed to the reference plate 117. One pull claw assembly is used to clamp the adjusting block 118, and the other two pull claw assemblies are used to clamp the workpiece 200 to be processed. The three pull claw assemblies are evenly distributed circumferentially, with two pull claw assemblies used to directly clamp the workpiece 200 to be processed, and the third pull claw assembly specifically used to clamp the counterweight system mounted on the reference plate 117. The counterweight system consists of the detachable adjusting block 118 and the counterweight 119. The counterweight 119 is fixed to the upper surface of the reference plate 117 by screws, and the adjusting block 118 is detachably mounted to the top of the counterweight 119 by screws. By replacing the adjusting block 118 with different specifications, the overall mass of the counterweight system can be precisely adjusted. Because the workpiece 200 is installed eccentrically, it tends to move linearly along the tangent of its circumferential trajectory during machining, potentially causing it to drift away from the center of the fixture. If the installation is unstable, the workpiece may rotate and fly out of the fixture. The adjusting block 118 and counterweight 119 are installed in the opposite position to the workpiece. Their function is to ensure the overall balance of the fixture's center of gravity during machining, preventing the workpiece from drifting away from the center. This innovative design of the three-jaw 148 combined with the counterweight 119 effectively balances the centrifugal force generated during the machining of the eccentric workpiece, preventing displacement or vibration during grinding. Furthermore, by adjusting the counterweight's mass, it can adapt to the machining requirements of workpieces of different specifications, significantly improving machining stability and accuracy, and providing a reliable guarantee for high-quality grinding of the eccentric pin hole 201.

[0065] Reference Figure 13In this embodiment, the reference plate 117 is provided with multiple steps 182 for supporting the workpiece 200 to be processed. Each step 182 has a wear-resistant body 188 on its upper surface, and all wear-resistant bodies 188 are of equal height. Specifically, the upper surface of the reference plate 117 is provided with multiple steps 182 for supporting the workpiece 200 to be processed. Each step 182 has a wear-resistant body 188 (such as a cemented carbide block) embedded in or fixed to its upper surface by screws. All wear-resistant bodies 188 have their upper surfaces at the same horizontal plane and are set at the same height. When the workpiece 200 to be processed is placed on the step 182, the wear-resistant body 188 contacts the bottom surface of the workpiece. This reduces direct friction and wear between the workpiece and the reference plate 117, improving the service life of the reference plate 117. Furthermore, the equal height of the upper surfaces of the wear-resistant bodies 188 ensures the horizontality of the workpiece, providing a stable support surface for subsequent centering and clamping.

[0066] In this embodiment, the edge of the reference fixing plate 116 is provided with multiple arc-shaped notches to avoid the movement of the claw assembly. Specifically, the edge of the reference fixing plate 116 is machined with multiple arc-shaped notches, the curvature and position of which match the movement trajectory of the claw assembly. This is used to avoid the rotational movement of the claw assembly when clamping or releasing the workpiece, prevent interference between the reference fixing plate 116 and the claw assembly, and ensure that the claw assembly can smoothly rotate and move up and down toward or away from the workpiece 200 to be processed, thereby achieving effective clamping and releasing of the workpiece.

[0067] This utility model embodiment also provides a grinding machine tool, including the eccentric grinding fixture described in the above embodiments. Specifically, the eccentric grinding fixture has been described in detail in the above embodiments, and for the sake of brevity, it will not be described again here.

[0068] Specifically, the grinding machine tool includes a bed, a worktable mounted on the bed, and an eccentric grinding fixture. The eccentric grinding fixture is mounted on the worktable, and its reference plate assembly is used to support the workpiece 200 to be processed. The centering assembly 750, driven by the first driving member 510, makes the centering pin 111 coincide with the axis of the eccentric pin hole 201 of the workpiece. The clamping mechanism 700, driven by the second driving member 511, clamps the workpiece. The grinding wheel axis of the grinding machine tool is pre-calibrated to coincide with the axis of the centering pin 111, thereby realizing the grinding of the eccentric pin hole 201 of the workpiece. By applying the eccentric grinding fixture, the grinding machine tool solves the problems of difficult positioning and low coaxiality accuracy when processing the eccentric pin hole 201 of non-circular workpieces, and ensures the accuracy and stability of the pin hole 201 grinding process.

[0069] Reference Figures 1-14 To facilitate understanding of the structure of the eccentric grinding fixture in this embodiment of the present invention, the following description will further illustrate the specific connection structure, installation process, and processing process of the eccentric grinding fixture.

[0070] Specific connection structure:

[0071] First, the centering pin 111 is passed through the limiting post 113. Then, the limiting post 113 is connected to the mounting base 101 by threads. Finally, the centering pin 111 is passed through the guide sleeve 128. The centering pin 111, the limiting post 113, the mounting base 101, and the guide sleeve 128 form the centering assembly 750. The centering assembly 750 is threadedly connected and fixed to the first driving component 510 by the external thread 193. The three claw assemblies are fixed to the chuck base plate 108 by fixing screws 105 and to the chuck seat 107 by fixing nuts 120. The chuck base plate cover 109 is combined with the chuck base plate 108 by fixing screws 106. The fixing screw 102 fixes the bushing nut 103 to the chuck bushing 104, and the fixing screw 102 will be embedded in the limiting ring groove 190 of the chuck bushing 104. The outer diameter of the limiting step 191 of the chuck bushing 104 is larger than the inner circle 192 of the chuck seat 107, and the outer circle of the bushing nut 103 is also larger than the inner circle 192 of the chuck seat 107. In this way, the limiting step 191 of the chuck bushing 104 and the bushing nut 103 can restrict the chuck seat 107. Thus, the three claw assemblies, chuck bushing 104, bushing nut 103, chuck base plate 109, chuck base plate cover 108, and chuck seat 107 can form a clamping mechanism 700.

[0072] In this design, the mounting base 101 is connected to the first drive component 510 of the grinding machine tool via an external thread. The chuck bushing 104 has an internal thread for connection to the second drive component 511 of the grinding machine tool. The first drive component 510 of the grinding machine tool controls the reciprocating motion of the centering assembly 750, and the second drive component 511 controls the reciprocating motion (clamping and releasing the workpiece) of the clamping mechanism 700. The bushing nut 103 is fixed to the chuck bushing 104 by fixing screws 102 on both sides. Other components include a sealing nut 301, a snap ring 302, a fastening pin 303, a needle roller radial bearing 304, a locking nut 305, and threads. The 306 sets form the pull rod fastening assembly 300. This fixture solution has three pull claw assemblies with the same structure: A250, B251, and C252. Each of the three pull claw assemblies consists of a pad 147, a pull claw 148, a floating connecting block 152, a pull claw fixing shaft 145, an adjusting support plate 142, an inner grinding bearing seat 141, the pull rod fastening assembly 300, a shaft pin 144, a snap ring 143, a transmission shaft 140, a fixing bolt 146, a fixing bolt 150, a fixing bolt 149, a fixing screw 151, a fixing screw 154, a fixing nut 155, and a fixing nut 153. The clamping mechanism 700 consists of pull claw assembly A250, pull claw assembly B251, pull claw assembly C251, chuck seat 107, bushing nut 103, and chuck bushing 104, while the centering assembly 750 consists of mounting seat 101, centering pin 111, limit post 113, and guide sleeve 128. The chuck base plate cover 108 has a triangular clearance arc 184 in the middle to allow space for the chuck seat 107 during movement. The chuck base plate 109 has three frustums 185, and each frustum 185 has a fixing threaded hole for supporting and fastening the reference mounting plate 112. The chuck base plate 109 is mounted on the chuck base plate cover 108 by fixing screws 106. The three claw assemblies A250, B251, and C252 all pass through the through holes 186 in the chuck base plate 109. The three claw assemblies are mounted on the chuck seat 107 by fixing nuts 120. The reference mounting plate 112 is mounted on the chuck base plate 109 by fixing screws 110. The triangular part of the reference mounting plate 112 has a clearance arc 800 to allow for the reciprocating motion of the claw assemblies. When the workpiece 200 is installed, the reference fixing plate 116 is mounted on the reference mounting plate 112 by fixing screws 114. The reference fixing plate 116 has an arc-shaped notch to allow the pull claw assembly to move. The reference plate 117 is mounted on the reference fixing plate 116 by fixing screws 115. The reference plate 117 has 6 arc-shaped steps 182. The wear-resistant body 188 is tightly fitted and embedded on the 6 arc-shaped steps 182 on the reference plate 117 and is slightly higher than the arc-shaped steps 182 of the reference plate. The six wear-resistant bodies 188 are of equal height, which ensures the reference flatness when the workpiece 200 is installed. Because the reference plate 117 has a lot of contact with the workpiece 200, the function of the wear-resistant body 188 here is to improve the wear resistance of the reference plate 117 and increase the service life of the reference plate 117.Two locating pins 126 are threadedly connected to the reference plate 117. The locating pins 126 are used to quickly position the workpiece 200 when it is installed. A limiting post 113 is threadedly connected to the limiting seat 101. A centering pin 111 passes through the limiting hole of the limiting post 113 and is installed on the limiting post 113. The function of the centering pin 111 is to center the pin hole 201 to be machined on the workpiece 200, ensuring that the pin hole 201 to be machined is coaxial with the origin of the grinding machine. A guide sleeve 128 passes through the centering pin 111 and is installed on the reference plate 117 by a fixing screw 127. A counterweight 119 is installed on an adjusting block 118 by a fixing screw 125. The counterweight 119 and adjusting block 118 are then installed on the reference plate 117 by a fixing screw 124. The function of the counterweight 119 and adjusting block 118 is to balance the weight of the workpiece and the fixture, ensuring that the fixture maintains force balance during machining. C252 is used to tighten and fix the adjusting block, while A250 and B251 are used to tighten and fix the workpiece 200.

[0073] Installation process:

[0074] When installing this fixture, first assemble the pull rod fastening assembly 300, pass the fastening pin 303 through the center hole of the threaded sleeve 306, then install the snap ring 302 on the fastening pin 303, then pass the needle roller radial bearing 304 through the fastening pin 303 and install it into the threaded sleeve 306, then install the fastening nut 305 onto the threaded sleeve 306 through a threaded connection, and finally install the sealing nut 301 onto the threaded sleeve 306 through a threaded connection. The above constitutes the pull rod fastening assembly 300. Next, assemble the pull claw assembly. First, pass the inner grinding shaft sleeve 141 through the transmission shaft 140. Then, use the pull rod fastening assembly 300 to pass through the side threaded hole of the inner grinding shaft sleeve 141. Slide the fastening pin 303 of the pull rod fastening assembly 300 into the guide groove 181 of the transmission shaft 140. Assemble the pull rod fastening assembly 300 with the inner grinding shaft sleeve 141 through a threaded connection. At this time, the transmission shaft 140 can rotate under the action of the guide groove 181. Install the adjusting support plate 142 on the inner grinding shaft sleeve 141 through a threaded connection and fix it on the side with a fixing screw 154 and a fixing nut 153. The sliding groove 194 of the pull claw fixing shaft 145 is slidably fitted with the drive shaft 140. The pull claw fixing shaft 145 is slidably fitted with the drive shaft 140 through the sliding groove 194, and the two are coaxial. Then, the drive shaft 140 and the pull claw fixing shaft 145 are fixed with fixing screws 146. The floating connecting block 152 is slidably fitted with the upper sliding groove 195 of the pull claw fixing shaft 145. After inserting the floating connecting block 152 into the upper sliding groove 195 of the pull claw fixing shaft 145, and aligning the side pin holes of the floating connecting block 152 with the side pin holes of the pull claw fixing shaft 145, the shaft pin 144 is inserted into the floating connecting block. The side pin holes of block 152 and the side pin holes of claw fixing shaft 145 are connected, and a retaining ring 143 is installed on the shaft pin 144 for fixation. The floating connecting block 152 is fixed with fixing screw 151 and fixing nut 155. In this way, the claw fixing shaft 145 and the floating connecting block 152 can be fixed together. The pad 147 is installed on the claw 148 with fixing screw 149, and the claw 148 and the pad 147 are installed on the floating connecting block 152 with fixing screw 150. In this way, the claw assembly A250 is assembled. The installation process of the remaining claw assemblies B251 and C252 is the same as above. Next, the chuck base plate cover 108 is passed through the chuck seat 107 through the spiral groove 184. The assembled claw assemblies A250, B251, and C252 are passed through the through holes 186 of the chuck base plate 109 and connected to the chuck seat 107 by fixing nuts 120. The chuck base plate 109 is then installed on the chuck base plate 108 by fixing screws 106. The three claw assemblies are then connected to the chuck base plate cover 109 by fixing screws 105. In this way, the chuck bushing 104, bushing nut 103, chuck seat 107, and the three claw assemblies form the clamping mechanism 700.The reference mounting plate 112 is passed through the centering pin 111 and mounted on the chuck base plate 109 by the fixing screw 110. The reference fixing plate 116 is mounted on the reference mounting plate 112 by the fixing screw 114. First, the wear-resistant body 188 is tightly fitted into the arc step 182 on the reference plate. Then, the reference plate is passed through the centering pin 111 and mounted on the reference fixing plate 116 by the fixing screw 115. The guide sleeve 128 is passed through the centering pin 111 and mounted on the reference plate 117 by the fixing screw 127. The counterweight 119 is fixed to the adjusting block 118 with fixing screws 125. Then, the adjusting block 118 and the counterweight 119 are installed on the reference plate 117 with fixing screws 124. The pull claw assembly is adjusted to the loose state. Finally, the centering pin 111 is passed through the limit post 113, and the centering pin 111 and the limit post 113 are fixed to the mounting base 101 by threads. Then, the chuck bushing 104 is passed through the star chuck seat 107, and the bushing nut 103 is passed through the lower end of the chuck bushing 104. The bushing nut 103 is locked and fixed to the chuck bushing 104 on both sides with fixing screws 102. The centering assembly 750 is composed of the mounting base 101, the limit post 113, the centering pin 111, and the guide sleeve 128. The centering assembly 750 is adjusted to be coaxial with the machine tool grinding wheel. The fixture is installed on a grinding machine tool and connected to the first drive component of the grinding machine tool via the external thread 193 of the mounting base 101. Then, the internal thread of the chuck bushing is connected to the second drive component, thus completing the installation process of the fixture.

[0075] Processing procedure:

[0076] It should be noted that when the first driving member 510 moves forward, the centering pin 111 extends; when the first driving member 510 moves backward, the centering pin 111 retracts. When the second driving member 511 moves forward, the clamping mechanism 700 releases; when the second driving member 511 moves backward, the clamping mechanism 700 clamps.

[0077] First, when machining begins, the first drive member 510 is in the forward state, and the centering pin 111 of the centering assembly 750 is in the extended state. The second drive member 511 is in the forward state, and the clamping mechanism 700 is in the released state. The pin hole 201 of the workpiece 200 is aligned with the centering pin 111, and the other two positioning holes are aligned with the positioning pins 126, thereby mounting the workpiece 200 on the grinding fixture.

[0078] Then, the second drive member 511 retracts and drives the clamping mechanism 700 to clamp the workpiece 200. The first drive member 510 then retracts and drives the centering pin 111 of the centering assembly 750 to exit. At this time, the grinding machine tool controls the grinding wheel to process the pin hole 111 of the workpiece 200. After processing, the grinding wheel exits.

[0079] Finally, the first driving component 510 moves forward, causing the centering pin 111 of the centering component 750 to extend. The second driving component 511 moves forward, causing the clamping mechanism 700 to release the workpiece 200. Then, the workpiece 200 is removed, and a new workpiece is replaced for processing, completing one processing cycle.

[0080] The first driving component controls the movement of the mounting base 101, thereby controlling the forward and backward movement of the centering assembly. The second driving component controls the movement of the chuck sleeve 104. When the second driving component moves backward, the chuck sleeve 104 drives the chuck seat 107 to move backward. Since the guide groove 181 of the transmission shaft 140 in the claw assembly is in sliding fit with the fastening pin 303 of the pull rod fastening assembly 300, the inner grinding sleeve 141 and the pull rod fastening assembly 300 remain stationary. When moving backward, the chuck seat 107 drives the other claw assemblies to rotate and move backward. As a result, claw assembly A can clamp the adjusting block 118, and claw assemblies B and C clamp the workpiece. When the second driving component moves forward, the chuck sleeve 104 drives the chuck seat 107 to move forward. The transmission shaft 140 in the claw assembly rotates forward due to the guide groove 181, and claw assembly A releases the adjusting block 118. Claw assemblies B and C release the workpiece 200, thereby achieving the function of quickly changing the workpiece.

[0081] When machining workpieces with the same positioning hole position but different heights, it is only necessary to replace the corresponding model of the pull claw assembly and counterweight. Moreover, the solution has a simple structure, and the clamping and releasing of the fixture can be achieved by controlling the movement of the hydraulic cylinder of the grinding machine, realizing the automated process, providing stable clamping force, improving the quick clamping of workpieces, realizing the universality of the eccentric grinding fixture, and meeting the needs of rapid changeover in mass production of workpieces.

[0082] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this utility model, and these modifications or substitutions should all be covered within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. An eccentric grinding fixture, characterized in that, include: A reference plate assembly for carrying a workpiece to be processed with an eccentric pin hole, a centering assembly disposed on the reference plate assembly, and a first driving member, wherein the first driving member is connected to the centering assembly, the centering assembly includes a centering pin, and the first driving member is used to drive the centering pin to align with the pin hole passing through the workpiece to be processed so that the centering pin coincides with the axis of the pin hole.

2. The eccentric grinding fixture according to claim 1, characterized in that, The centering assembly further includes a guide sleeve disposed on the reference plate assembly. The guide sleeve has a guide hole. One end of the centering pin passes through the guide hole, and the other end is used to connect with the first driving member. The first driving member is used to drive the centering pin to move axially along the guide hole.

3. The eccentric grinding fixture according to claim 2, characterized in that, The centering component further includes a limiting post and a mounting base. The other end of the centering pin is provided with a fixed end. The fixed end of the centering pin passes through the limiting post. The limiting post is fixedly connected to the top of the mounting base. The bottom of the mounting base is connected to the first driving member. The upper end face of the fixed end is horizontally attached to the top surface of the inner wall of the limiting post, and the lower end face is horizontally attached to the top surface of the mounting base.

4. The eccentric grinding fixture according to claim 2, characterized in that, The centering assembly further includes at least two positioning pins, which are disposed on the reference plate assembly and are used for alignment with positioning holes passing through the workpiece to be processed.

5. The eccentric grinding fixture according to any one of claims 1-4, characterized in that, It also includes a clamping mechanism and a second driving member. The clamping mechanism is disposed on the reference plate assembly, and the second driving member is used to drive the clamping mechanism to clamp or release the workpiece to be processed.

6. The eccentric grinding fixture according to claim 5, characterized in that, The clamping mechanism includes a chuck assembly, a claw assembly and a lever fastening assembly disposed on the chuck assembly. The chuck assembly is fixedly connected to the reference plate assembly. The second driving member is used to drive the claw assembly to move toward or away from the workpiece to clamp or release the workpiece. The lever fastening assembly is used for transmission engagement with the claw assembly to drive it to rotate during movement.

7. The eccentric grinding fixture according to claim 6, characterized in that, The chuck assembly includes a chuck and a chuck base. The chuck is fixedly connected to the reference plate assembly. Multiple pull claw assemblies pass through the chuck and are rotatably connected to the chuck base. The chuck base is connected to the second drive member.

8. The eccentric grinding fixture according to claim 7, characterized in that, The chuck assembly further includes a chuck bushing, the chuck seat has a shaft hole, the chuck bushing is fixed in the shaft hole, the chuck bushing is fixedly connected to the second drive member, and the centering component passes through the chuck bushing.

9. The eccentric grinding fixture according to claim 6, characterized in that, The pull claw assembly includes a pull claw and a drive shaft fixedly connected to the pull claw. A guide groove is provided on the shaft, and the guide groove extends along the axial and circumferential directions of the drive shaft. The pull rod fastening assembly includes a fastening pin, which slides with the guide groove to drive the pull claw to rotate and lift.

10. The eccentric grinding fixture according to claim 9, characterized in that, The puller assembly also includes a pad that is detachably mounted on the side of the puller facing the workpiece to be processed.

11. The eccentric grinding fixture according to claim 6, characterized in that, The reference plate assembly includes a reference plate, a reference fixing plate, and a reference mounting plate. The reference plate is fixed on the reference fixing plate, the reference fixing plate is fixed on the reference mounting plate, and the reference mounting plate is fixed on the chuck assembly.

12. The eccentric grinding fixture according to claim 11, characterized in that, The pull claw assembly has three parts, and the reference plate assembly further includes a counterweight and an adjustment block. The adjustment block is detachably fixed on the counterweight and the counterweight is fixed on the reference plate. One of the pull claw assemblies is used to clamp the adjustment block, and the other two pull claw assemblies are used to clamp the workpiece to be processed.

13. The eccentric grinding fixture according to claim 11, characterized in that, The reference plate is provided with multiple steps for supporting the workpiece to be processed. Each step has a wear-resistant body on its upper surface, and each wear-resistant body is of equal height.

14. The eccentric grinding fixture according to claim 11, characterized in that, The edge of the reference fixing plate is provided with multiple arc-shaped notches to avoid the movement of the pull claw assembly.

15. A grinding machine tool, characterized in that, Including the eccentric grinding fixture as described in any one of claims 1-14.

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