A hydraulic fixture for batch precision turning

Abstract

This utility model discloses a hydraulic clamping fixture for batch precision turning, belonging to the field of machining fixture technology, and solves the problem that existing three-jaw chucks cannot meet the requirements. The outer circular sides of both ends of the bushing are tightly fitted with the inner hole of the housing, and a cavity is formed between the outer circular side of the middle of the bushing and the housing. The housing has two symmetrical radial through holes, both of which communicate with the cavity. Two pistons are respectively assembled in the two symmetrical radial through holes, and each is fitted with a small clearance to its corresponding radial through hole. A hydraulic sealing ring is circumferentially fitted on the outside of each piston, and the hydraulic sealing ring is tightly fitted with the corresponding radial through hole. An advance / retreat bolt is screwed to the top of each piston. The oil plug is a through hole on the housing that communicates with the cavity, and a plug is provided on the oil plug. This utility model surpasses the traditional three-jaw chuck clamping method, providing a noiseless and highly efficient precision turning solution.

Description

Technical Field

[0001] This utility model relates to the field of machining fixture technology, and in particular to a hydraulic fixture for batch precision turning. Background Technology

[0002] When precision turning non-ferrous metal workpieces using diamond tools, it is typically necessary to fix the outer diameter of shaft-type parts to allow for precision machining of another outer diameter; similarly, for bushing parts, the outer diameter also needs to be fixed for precision turning of the inner hole. In this process, traditional three-jaw chucks (hard jaws) are unsuitable for such precision operations due to their rigid contact; therefore, specially designed three-jaw chucks (soft jaws) must be used for clamping. These specialized soft-jaw chucks require special manufacturing to ensure machining accuracy.

[0003] Similarly, when precision turning high-hardness materials such as hardened steel, bearing steel, and high-speed steel using cubic boron nitride tools, the same clamping strategy is required. In this case, conventional three-jaw chucks (hard jaws) are not suitable, and three-jaw chucks (soft jaws) specifically designed for precision machining must be used. The manufacture of these special chucks requires special processes to meet the demands of high-precision machining.

[0004] Therefore, in the field of machining, especially when precision turning workpieces such as non-ferrous metals or quenched steel, traditional hard-jaw three-jaw chucks cannot meet the requirements for clamping accuracy and surface protection. Traditional precision turning processes often rely on specially manufactured soft-jaw three-jaw chucks, which not only increases production costs but also extends preparation time. Utility Model Content

[0005] This invention proposes a hydraulic fixture for batch precision turning to solve the problems existing in the prior art.

[0006] A hydraulic fixture for batch precision turning includes a hydraulic seal ring, a feed bolt, two pistons, an oil plug, a bushing, and a housing. The outer circumferences at both ends of the bushing are tightly fitted with the inner bore of the housing. A cavity is formed between the outer circumference of the bushing in the middle and the housing. The housing has two symmetrical radial through holes, both communicating with the cavity. The two pistons are respectively assembled in the two symmetrical radial through holes, each with a small clearance fit to its corresponding radial through hole. The hydraulic seal ring is circumferentially fitted around the outside of each piston, and is tightly fitted with its corresponding radial through hole. The feed bolt is screwed to the top of each piston. The oil plug is a through hole on the housing communicating with the cavity, and a plug is provided on the oil plug.

[0007] When the hydraulic clamp is in use, the cavity is filled with machine oil.

[0008] Furthermore, the housing has a mounting groove at its tail end, through which the hydraulic clamp is mounted on the lathe spindle.

[0009] Furthermore, each piston is fitted with two hydraulic seal rings on its outer side.

[0010] Furthermore, the two hydraulic seals are made of rubber.

[0011] Furthermore, the bushing is made of spring steel.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] 1. The hydraulic clamp of this utility model has the following significant beneficial effects:

[0014] 1. This utility model successfully designs a hydraulic clamping fixture specifically for batch precision turning, which can effectively replace the traditional three-jaw chuck (hard jaw) clamping method, bringing a new option to the field of precision machining.

[0015] 2. The hydraulic clamp of this utility model eliminates the dependence on oil pumps and achieves self-sufficiency without external oil supply, thereby eliminating the noise problem of the hydraulic system and providing operators with a quieter working environment.

[0016] 3. The fixture design of this utility model makes the workpiece clamping process quick and easy, greatly improving work efficiency and reducing operational difficulty. After processing, the fixture of this utility model allows for quick and easy unloading of the workpiece, which not only improves production efficiency but also makes the replacement of individual workpieces faster.

[0017] 5. Unlike traditional axial single-piston cylinders, this utility model adopts a unique radial double-piston cylinder design, which provides the clamp with a more stable and uniform clamping force.

[0018] 6. The fixture of this utility model ingeniously integrates positioning and clamping functions into a single component, namely a bushing that achieves clamping through liquid pressure. This design simplifies the structure of the fixture, reduces the number of components, and improves the reliability and ease of operation of the fixture. Attached Figure Description

[0019] Figure 1 This is a cross-sectional view of a hydraulic fixture for batch precision turning according to the present invention;

[0020] Figure 2 This is a partial cross-sectional view of the bushing and housing.

[0021] Among them, 1 is the lathe spindle, 2 is the hydraulic seal ring, 3 is the advance and retraction bolt, 4 is the two pistons, 5 is the oil plug, 6 is the bushing, and 7 is the housing. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present utility model, and 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.

[0023] A hydraulic fixture for batch precision turning includes a hydraulic seal ring 2, a feed bolt 3, two pistons 4, an oil plug 5, a bushing 6, and a housing 7. The outer circumferences at both ends of the bushing 6 are tightly fitted with the inner bore of the housing 7. A cavity is formed between the outer circumference of the middle portion of the bushing 6 and the housing 7. The housing 7 has two symmetrical radial through holes, both communicating with the cavity. The two pistons 4 are respectively assembled in the two symmetrical radial through holes, each with a small clearance fit with its corresponding radial through hole. The hydraulic seal ring 2 is circumferentially fitted around the outside of each piston 4, and is tightly fitted with its corresponding radial through hole. The feed bolt 3 is screwed to the top of each piston 4. The oil plug 5 is a through hole on the housing 7 communicating with the cavity, and a plug is provided on the oil plug 5.

[0024] When the hydraulic clamp is in use, the cavity is filled with machine oil.

[0025] Furthermore, the housing 7 has a mounting groove at its tail end, through which the hydraulic clamp is mounted on the lathe spindle 1.

[0026] Specifically, the fixture housing 7 is mounted on the lathe spindle 1. The lathe is started, and the inner hole of the bushing 6 is precision machined so that the inner hole of the bushing 6 is slightly larger than the outer diameter of the workpiece to be clamped.

[0027] Furthermore, each piston 4 is fitted with two hydraulic sealing rings 2 on its outer side.

[0028] Specifically, the outer circle of the hydraulic seal ring 2 fits tightly with the radial through hole, and the upper advance and retraction bolt 3 is screwed on. The housing 7, piston 4, and hydraulic seal ring 2, etc., constitute the hydraulic cylinder.

[0029] Furthermore, the two hydraulic sealing rings 2 are made of rubber.

[0030] Specifically, the hydraulic seal ring 2 is made of rubber, which is flexible and does not affect the linear reciprocating motion of the piston 4 within the radial through hole of the housing 7.

[0031] Furthermore, the bushing 6 is made of spring steel.

[0032] Specifically, refer to Figure 2 As shown, the bushing 6 is made of spring steel. The wall thickness of the bushing 6 is thick at both ends and thin in the longer middle part. This is to allow it to fit with the outer shell 7 to form a cavity and to facilitate elastic deformation.

[0033] An operating method for a hydraulic fixture used for batch precision turning, based on the aforementioned hydraulic fixture for batch precision turning, the operating method of the hydraulic fixture for batch precision turning includes the following steps:

[0034] S100. Tightly fit the outer circular sides of both ends of the bushing 6 with the inner hole of the housing 7.

[0035] S200. Install the housing 7 on the lathe spindle 1 and start the lathe to precisely machine the inner hole of the bushing 6 so that its size is slightly larger than the outer diameter of the workpiece to be machined.

[0036] S100. Install the hydraulic sealing ring 2 onto the piston 4, and assemble the piston 4 in the radial through hole of the housing 7 to ensure that there is a small clearance fit between the outer circle side of the piston 4 and the radial through hole. At the same time, install four liquid sealing rings 2 to ensure that the outer circle side of the liquid sealing ring 2 fits tightly with the radial through hole. Then install the infeed bolt 3 to complete the assembly of the hydraulic cylinder.

[0037] S300. Rotate the housing 7 so that the oil plug 5 faces upward, and pour the casing oil through the oil plug 5. After pouring the oil, let it stand for about eight hours to ensure that the air in the oil is completely released. After the air is released, tighten the oil plug 5.

[0038] S400. Insert the precision-machined shaft or workpiece into the inner hole of the bushing 6 with a clearance fit to position the workpiece. Then screw in the advance and retraction bolt 3 to advance it a short distance. Apply pressure to the bushing 6 with hydraulic oil to reduce the inner hole size of the bushing 6 and tightly clamp the outer circle of the shaft or workpiece.

[0039] S500: Use diamond tools, cubic boron nitride tools or ordinary tools to perform precision turning of shafts or workpieces.

[0040] S600. After machining the current shaft or workpiece, rotate the housing 7 so that the advance and retraction bolt 3 faces upward, and then unscrew the advance and retraction bolt 3 to reduce the pressure on the bushing 6, so that the inner hole size of the bushing 6 is restored, and the machined shaft or workpiece can be easily removed by utilizing the elasticity of its own spring steel.

[0041] S700, return to S100, and continue machining the next shaft or workpiece.

[0042] Specifically, the hydraulic clamping operation method of the present invention achieves rapid and efficient workpiece clamping and unloading through a simplified clamping process, precise hydraulic control, and easy-to-maintain design, thereby improving machining accuracy and production efficiency. Furthermore, this method enhances environmental adaptability and operational convenience by eliminating hydraulic noise, flexibly clamping workpieces of different sizes, and reducing costs through the use of housing oil. It is suitable for precision turning of various tool materials, meeting diverse machining needs.

[0043] Furthermore, prior to the S100, it also includes:

[0044] S000. Before pressing, the bushing 6 is placed in a cold environment to cool, so that the bushing 6 can be pressed into the inner hole of the housing 7 more easily during subsequent assembly.

[0045] This utility model discloses a hydraulic fixture for batch precision turning. Before pressing, the bushing 6, with an inner hole allowance, is placed in a refrigerator overnight. The next morning, it is easily pressed into the hole of the housing 7 from left to right. The hydraulic sealing rings 2 are then assembled onto the pistons 4. Opposite pistons 4 are assembled in two symmetrical radial holes of the housing 7, with a small clearance fit between the outer circle of the piston and the radial hole. There are four hydraulic sealing rings 2 in total, with their outer circles tightly fitting the radial holes. The hydraulic sealing rings 2 are made of rubber, have good flexibility, and do not affect the linear reciprocating motion of the piston within the radial holes of the housing. The lower sealing bolt is tightened, and the upper infeed bolt 3 is tightened. The housing, pistons, sealing rings, etc., constitute the hydraulic cylinder. Before use, the housing 7 is rotated so that the oil plug 5 is at the top. Fill the fixture with machine oil from the oil plug 5. Use expensive machine oil for both rust and corrosion prevention and as hydraulic fluid. After filling, wait eight hours to allow all air to escape, usually overnight. Once all air has escaped, tighten the plug at oil plug 5 to prevent air bubbles from remaining in the oil. Insert the precision-machined shaft (workpiece) into the inner hole of bushing 6 with a clearance fit to position the workpiece and restrict its four degrees of freedom. Tighten the head-hardened advance / retract bolt 3, which advances a small distance, putting pressure on bushing 6 with the hydraulic oil in the cavity. This reduces the inner diameter of bushing 6, tightly clamping the shaft (workpiece outer diameter) within bushing 6. This clamping force comes from hydraulic pressure. After machining the first part, rotate the fixture housing 7 so that advance / retract bolt 3 is at the top. Slightly loosen advance / retract bolt 3, allowing it to retract a small distance. The hydraulic oil is depressurized, and the inner diameter of bushing 6 returns to its original shape, as bushing 6 is made of spring steel. The workpiece can then be easily removed. The second part is then machined, and this process is repeated until all machining is completed.

[0046] This invention can be used for various precision turning operations with diamond tools, cubic nitrogen nitride tools, or ordinary tools.

[0047] The above are merely specific embodiments of this application, but the scope of protection of this application 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 application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A hydraulic fixture for batch precision turning, characterized in that, The hydraulic fixture for batch precision turning includes a hydraulic seal ring (2), a retracting bolt (3), two pistons (4), an oil plug (5), a bushing (6), and a housing (7). The outer circumferences at both ends of the bushing (6) are tightly fitted with the inner hole of the housing (7). A cavity is formed between the outer circumference of the middle part of the bushing (6) and the housing (7). The housing (7) has two symmetrical radial through holes, both of which communicate with the cavity. The two pistons (4) are respectively assembled in the two symmetrical radial through holes, and each has a small clearance fit with its corresponding radial through hole. The hydraulic seal ring (2) is circumferentially fitted on the outside of each piston (4), and the hydraulic seal ring (2) is tightly fitted with the corresponding radial through hole. The retracting bolt (3) is screwed to the top of each piston (4). The oil plug (5) is a through hole on the housing (7) that communicates with the cavity, and a plug is provided on the oil plug (5). When the hydraulic clamp is in use, the cavity is filled with machine oil.

2. A hydraulic fixture for batch precision turning according to claim 1, characterized in that, The housing (7) has a mounting groove at its tail end, and the hydraulic clamp is mounted on the lathe spindle (1) through the mounting groove.

3. A hydraulic fixture for batch precision turning according to claim 1, characterized in that, Each piston (4) is fitted with two hydraulic seals (2) on its outer side.

4. A hydraulic fixture for batch precision turning according to claim 3, characterized in that, The two hydraulic seals (2) are made of rubber.

5. A hydraulic fixture for batch precision turning according to claim 1, characterized in that, The bushing (6) is made of spring steel.

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