A centering device

Abstract

The utility model discloses a kind of clamping centering devices, including clamping seat, centering mechanism and fixed clamp, the centering mechanism and fixed clamp are set on clamping seat, the centering mechanism includes lifting piece and top cover, the top cover is placed above lifting piece, three locating ports are provided in the upper portion of the side wall of top cover, the locating port is set with equal interval around top cover, the locating port is inclined from outer upper direction to inner lower side, locating ball is loaded in the locating port, the upper portion of lifting piece is inwards contracted and forms adjusting surface, the inner side of locating ball is in contact with adjusting surface, when lifting piece rises, adjusting surface moves up and pushes three locating balls to move synchronously outward and contact with the inner ring of oil distribution disc, so as to center oil distribution disc, the fixed clamp has three, fixed clamp cooperates with centering mechanism to stably hold oil distribution disc, and three fixed clamps can disperse stress, reduce the loss of single fixed clamp, prolong maintenance cycle.

Description

Technical Field

[0001] This utility model relates to the field of CNC machine tool metal cutting processing, and in particular to a clamping and centering device. Background Technology

[0002] CNC machine tool machining often requires clamping and fixing the workpiece. The clamping method plays a crucial role in the machining of the part; a good clamping method can improve the machining accuracy. When machining oil distribution plates, commonly used fixtures include... Figure 1 As shown, it includes a main support platform 81, a pressure plate 82, and a fastening nut 83.

[0003] Traditional fixtures have the following drawbacks: 1. They cannot guarantee zeroing the center. To accommodate the oil distribution plate, the center column of the main support platform and the center hole of the oil distribution plate are clearance-fitted, with a clearance between 0.5 and 0.8 mm. After manual clamping, there will be a concentricity error between the center of the oil distribution plate and the center of the column, which will cause offset errors in the machining area, thus reducing machining accuracy; 2. The tightening nut and screw require sufficient clamping force. The middle screw becomes a stress concentration center, which aggravates the wear of the screw and makes it prone to damage, requiring maintenance approximately every 5 months; 3. Insufficient clamping preload causes displacement during machining. Existing fixtures only restrict vertical freedom. If the nut is not tightened to the required torque during clamping, the workpiece is prone to displacement in the front, back, left, and right directions during machining. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a clamping and centering device that can reduce concentricity error.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a clamping and centering device, comprising a clamping base, a centering mechanism, and a fixing fixture. The centering mechanism and the fixing fixture are disposed on the clamping base. The centering mechanism includes a lifting component and a top cover. The top cover is placed above the lifting component. A plurality of positioning holes are provided on the upper part of the side wall of the top cover. The positioning holes are arranged at equal intervals around the top cover. The positioning holes are inclined from the upper outer side to the lower inner side. Positioning balls are inserted into the positioning holes. The upper part of the lifting component contracts inward to form an adjustment surface. The inner side of the positioning balls contacts the adjustment surface. A plurality of fixing fixtures are arranged around the centering mechanism.

[0006] Furthermore, the lifting component includes a lifting cylinder body and a lifting cylinder rod. The lifting cylinder body is fixedly mounted on a clamping seat, and the lifting cylinder rod is movably mounted on the lifting cylinder body, capable of moving up and down along the lifting cylinder body. The clamping seat has a mounting groove in the middle, and the bottom of the lifting cylinder body is inserted into the mounting groove. The bottom of the lifting cylinder body has an air chamber, and the lower part of the lifting cylinder rod is inserted into the air chamber. The clamping seat below the air chamber has a first air port, and the clamping seat has a first gas channel communicating with the first air port.

[0007] Furthermore, the bottom of the lifting cylinder rod extends outward to form a limiting ring, and the lifting cylinder body above the limiting ring extends inward to form a limiting part. The outer diameter of the limiting ring is larger than the inner diameter of the limiting part, and the distance between the limiting ring and the limiting part is smaller than the distance between the lifting cylinder rod and the inner top surface of the top cover.

[0008] Furthermore, the bottom surface of the limiting part is provided with a second air port, and the clamping seat is provided with a second gas channel communicating with the second air port.

[0009] Furthermore, sealing rings are provided between the lifting cylinder body and the mounting groove, between the limiting ring and the lifting cylinder body, and between the limiting part and the lifting cylinder rod.

[0010] Furthermore, the fixing clamp includes a support rod, a clamping block, and a nut. The clamping block is provided with an installation port that fits onto the support rod. The clamping block is provided with a clamping part facing the centering mechanism. The nut is located above the clamping block and is threadedly connected to the support rod.

[0011] The beneficial effects of this utility model are as follows: 1. By raising the lifting component, the positioning balls move outward synchronously to contact the inner ring of the oil distribution plate, thereby centering the oil distribution plate and reducing concentricity error to within 0.02mm; 2. By fixing the oil distribution plate with several fixed clamps surrounding the centering mechanism, stress is dispersed, making the entire clamp more reasonable and greatly extending the maintenance cycle; 3. The centering mechanism and the fixed clamps work together for clamping, making it less prone to displacement during processing compared to traditional clamps. Attached Figure Description

[0012] Figure 1 For existing oil distribution plate clamps.

[0013] Figure 2 This is a schematic diagram of the overall implementation of the example.

[0014] Figure 3 This is a cross-sectional view of an embodiment.

[0015] Figure 4 This is a schematic diagram of the top cover.

[0016] Figure 5 This is a schematic diagram of the clamping base.

[0017] In the diagram: 1. Clamping seat; 11. First gas passage; 12. Second gas passage; 13. First gas port; 14. Mounting groove; 2. Centering mechanism; 3. Fixing fixture; 31. Clamping block; 32. Nut; 33. Support rod; 4. Oil distribution plate; 5. Lifting cylinder body; 51. Gas chamber; 52. Limiting part; 53. Second gas port; 6. Lifting cylinder rod; 61. Adjusting surface; 62. Limiting ring; 7. Top cover; 71. Positioning port; 72. Ball bearing; 81. Main support platform; 82. Pressure plate; 83. Fastening nut. Detailed Implementation Plan

[0018] The present invention will be further described below with reference to the accompanying drawings.

[0019] Example: A clamping and centering device includes a clamping base 1, a centering mechanism 2, and a fixing clamp 3. The centering mechanism 2 and the fixing clamp 3 are disposed on the clamping base 1. The centering mechanism 2 includes a lifting component and a top cover 7. The top cover 7 is placed above the lifting component. Three positioning holes 71 are provided on the upper part of the side wall of the top cover 7. The positioning holes 71 are equally spaced around the top cover 7 and are inclined from the upper outer side to the lower inner side. Positioning balls 72 are inserted into the positioning holes 71. The upper part of the lifting component retracts inward to form an adjusting surface 61. The inner side of the positioning balls 72 contacts the adjusting surface 61. When the lifting component rises, the adjusting surface 61 moves upward and pushes against the three positioning balls 72, which move outward synchronously to contact the inner ring of the oil distribution plate 4, thereby centering the oil distribution plate 4 and reducing concentricity error. After processing, the lifting component descends, and the positioning balls 72 move downward along the inwardly inclined positioning opening 71, thereby disengaging from the oil distribution plate 4. There are three fixing clamps 3, which are arranged around the centering mechanism 2. The fixing clamps 3, together with the centering mechanism 2, can stably clamp the oil distribution plate, and the three fixing clamps 3 can distribute stress, reduce the wear of a single fixing clamp 3, and extend the maintenance cycle.

[0020] The machining of 30 oil distribution plates was continuously tested, and the positional offset is shown in the table below.

[0021] Serial Number 1 2 3 4 5 6 7 8 9 10 Offset (mm) 0.012 0.011 0.015 0.017 0.015 0.014 0.012 0.014 0.016 0.017 Serial Number 11 12 13 14 15 16 17 18 19 20 Offset (mm) 0.011 0.012 0.012 0.012 0.015 0.014 0.013 0.015 0.017 0.016 Serial Number 21 22 23 24 25 26 27 28 29 30 Offset (mm) 0.012 0.012 0.014 0.016 0.014 0.013 0.015 0.018 0.017 0.013

[0022] Furthermore, the lifting component includes a lifting cylinder body 5 and a lifting cylinder rod 6. The lifting cylinder body 5 is fixedly mounted on the clamping seat 1 by screws. The lifting cylinder rod 6 is movably mounted on the lifting cylinder body 5 and can move up and down along the lifting cylinder body 5. The clamping seat 1 is provided with a mounting groove 14 in the middle. The bottom of the lifting cylinder body 5 is inserted into the mounting groove 14. The bottom of the lifting cylinder body 5 is provided with an air chamber 51. The lower part of the lifting cylinder rod 6 is inserted into the air chamber 51. The clamping seat 1 below the air chamber 51 is provided with a first air port 13. The clamping seat 1 is provided with a first gas channel 11 that communicates with the first air port 13. Before processing, high-pressure gas is input into the air chamber 51 through the first gas channel 11, causing the lifting cylinder rod 6 to rise.

[0023] Furthermore, the bottom of the lifting cylinder rod 6 extends outward to form a limiting ring 62, and the lifting cylinder body 5 above the limiting ring 62 extends inward to form a limiting part 52. The outer diameter of the limiting ring 62 is larger than the inner diameter of the limiting part 52, and the distance between the limiting ring 62 and the limiting part 52 is smaller than the distance between the lifting cylinder rod 6 and the inner top surface of the top cover 7. The limiting ring 62 and the limiting part 52 limit the lifting cylinder rod 6 to prevent it from being pushed out of the top cover.

[0024] Furthermore, the bottom surface of the limiting part 52 is provided with a second air port 53, and the clamping base 1 is provided with a second gas channel 12 that communicates with the second air port 53. After the processing is completed, the first gas channel 11 is depressurized, and high-pressure gas is injected into the second air port 53 through the second gas channel 12 to make the lifting cylinder rod 6 descend.

[0025] Furthermore, sealing rings are provided between the lifting cylinder body 5 and the mounting groove 14, between the limiting ring 62 and the lifting cylinder body 5, and between the limiting part 52 and the lifting cylinder rod 6.

[0026] Furthermore, the fixing fixture 3 includes a support rod 33, a clamping block 31, and a nut 32. The clamping block 31 is provided with an installation port that fits onto the support rod 33. The clamping block 31 is provided with a clamping part 311 facing the centering mechanism 2. The nut 32 is located above the clamping block 31 and is threadedly connected to the support rod 33. After centering the oil distribution plate 4, the clamping part 311 is made to face the oil distribution plate 4 and the nut 32 is rotated downwards so that the clamping block 31 clamps the oil distribution plate 4 to prevent displacement during the processing.

Claims

1. A chucking fixture, characterized by The device includes a clamping base, a centering mechanism, and a fixing fixture. The centering mechanism and fixing fixture are mounted on the clamping base. The centering mechanism includes a lifting component and a top cover. The top cover is positioned above the lifting component. The upper part of the side wall of the top cover is provided with several positioning holes. The positioning holes are evenly spaced around the top cover and are inclined from the upper outer side to the lower inner side. Positioning balls are inserted into the positioning holes. The upper part of the lifting component retracts inward to form an adjustment surface. The inner side of the positioning balls contacts the adjustment surface. Several fixing fixtures are arranged around the centering mechanism.

2. The clamping and centering device according to claim 1, characterized in that... The lifting component includes a lifting cylinder body and a lifting cylinder rod. The lifting cylinder body is fixedly mounted on a clamping seat, and the lifting cylinder rod is movably mounted on the lifting cylinder body and can move up and down along the lifting cylinder body. The clamping seat has a mounting groove in the middle, and the bottom of the lifting cylinder body is inserted into the mounting groove. The bottom of the lifting cylinder body has an air chamber, and the lower part of the lifting cylinder rod is inserted into the air chamber. The clamping seat below the air chamber has a first air port, and the clamping seat has a first gas channel communicating with the first air port.

3. The clamping and centering device according to claim 2, characterized in that... The bottom of the lifting cylinder rod extends outward to form a limiting ring, and the lifting cylinder body above the limiting ring extends inward to form a limiting part. The outer diameter of the limiting ring is larger than the inner diameter of the limiting part, and the distance between the limiting ring and the limiting part is smaller than the distance between the lifting cylinder rod and the inner top surface of the top cover.

4. The clamping and centering device according to claim 3, characterized in that... The bottom surface of the limiting part is provided with a second air port, and the clamping seat is provided with a second gas channel communicating with the second air port.

5. A clamping and centering device according to claim 4, characterized in that... A sealing ring is provided between the lifting cylinder body and the mounting groove, between the limiting ring and the lifting cylinder body, and between the limiting part and the lifting cylinder rod.

6. A clamping and centering device according to any one of claims 1-5, characterized in that... The fixing fixture includes a support rod, a clamping block, and a nut. The clamping block has an installation port that fits onto the support rod. The clamping block has a clamping part facing the centering mechanism. The nut is located above the clamping block and is threadedly connected to the support rod.

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