Linkage type hydraulic clamp

Abstract

The utility model relates to a hydraulic clamp, in particular to a linkage type hydraulic clamp which solves the technical problems that an existing clamp is difficult to overcome the defects that the machining precision of a workpiece is unstable and a pressing plate needs to be replaced manually at the same time. According to the utility model, the single-acting rotary clamping cylinder and the retreat lever clamping cylinder are used for pressing the end face of a workpiece, so that the machining precision of a part is more stable; a linkage type hydraulic loop is designed by utilizing the structural characteristics of a single-action rotary clamping cylinder and a retreat type lever clamping cylinder, the conversion between pressing plates is realized by controlling the oil filling direction of hydraulic oil, the processing of a workpiece can be completed without manually replacing the pressing plates, and the clamping efficiency is greatly improved.

Description

Technical Field

[0001] The utility model relates to a hydraulic clamp, in particular to a linkage type hydraulic clamp. Background Art

[0002] During the workpiece processing, it is usually necessary to use a fixture to fix it. Figure 1 The workpiece shown in the figure has the processing part indicated by the black solid line, the positioning surface is the bottom surface, and the positioning hole is the inner hole, which is processed on a vertical lathe. At present, the difficulty in designing a fixture for such workpieces is that it is difficult to determine the clamping method, for the following reasons:

[0003] For inner hole support and clamping: the workpiece is too thin (wall thickness T = 30mm, thickness H = 12.04mm, outer circle D = 415mm), and the inner hole support and clamping will easily cause the workpiece to deform, and the processing accuracy of the workpiece cannot be guaranteed;

[0004] For end face clamping: the machining accuracy of the workpiece can be guaranteed, but both the end face and the outer circle of the workpiece need to be processed, and the clamping plate of the fixture needs to be manually replaced, which will affect the processing cycle. Therefore, how to avoid replacing the clamping plate is the design difficulty of this type of fixture;

[0005] For the automatic avoidance fixture of the pressure plate: Since this type of workpiece is processed on a vertical lathe with a high processing speed, the automatic avoidance fixture of the pressure plate is not suitable for this type of workpiece.

[0006] A Chinese patent with publication number CN206779973U discloses a workpiece clamping system, including a hydraulic oil circuit board and a hydraulic pull clamp, which clamps the workpiece by fitting a clamping arm against the bottom edge of the workpiece. This clamping method is similar to end face clamping. Although it can ensure the accuracy of the workpiece, the pressure plate also needs to be manually replaced during the processing. Utility Model Content

[0007] The utility model aims to solve the technical problems that the existing clamps are difficult to simultaneously overcome the unstable workpiece processing precision and the need to manually replace the pressing plate, and to provide a linkage type hydraulic clamp.

[0008] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0009] A linkage hydraulic clamp, which is special in that it includes a clamp body, a leak-free shut-off valve, a leak-free pressure-maintaining valve, M first pressing plates, M retractable lever clamping cylinders, N single-acting rotary clamping cylinders and N second pressing plates, wherein M and N are both integers greater than or equal to 2;

[0010] The fixture body is provided with a positioning surface in contact with the bottom surface of the workpiece;

[0011] The M retractable lever clamping cylinders and the N single-acting rotary clamping cylinders are evenly distributed on the clamp body along the circumference, and the N single-acting rotary clamping cylinders are located on the inner side of the circumference of the M retractable lever clamping cylinders; the retractable lever clamping cylinder is located on the outer side of the workpiece, and the single-acting rotary clamping cylinder is located in the inner hole of the workpiece;

[0012] The M first pressing plates are respectively arranged on the M retreat-type lever clamping cylinders, and are used to cooperate with the retreat-type lever clamping cylinders to realize end surface clamping of the workpiece from the inside, and the first pressing plates are located below the positioning surface in the non-clamping state;

[0013] The N second pressing plates are respectively arranged on the N single-acting rotary clamping cylinders, and are used to cooperate with the single-acting rotary clamping cylinders to realize the clamping of the workpiece from the outer end surface;

[0014] The non-leakage pressure-maintaining valve is used to connect to the oil pressure source, the P end of the non-leakage pressure-maintaining valve is connected to the oil inlet of the single-acting rotary clamping cylinder and the release oil pressure end of the retreating lever clamping cylinder, and the R end is connected to the clamping oil pressure end of the retreating lever clamping cylinder;

[0015] The non-leakage stop valve is arranged on the oil path between the P end of the non-leakage pressure-maintaining valve and the oil inlet of the single-acting rotary clamping cylinder.

[0016] Further, it also includes an accumulator for preventing pressure release;

[0017] The accumulator is arranged on the oil circuit between the P end of the non-leakage pressure-maintaining valve and the oil inlet of the single-acting rotary clamping cylinder and the release oil pressure end of the retreat lever clamping cylinder.

[0018] Furthermore, the accumulator is a spring accumulator.

[0019] Furthermore, the model of the accumulator is JSS5050-HG.

[0020] Further, a pressure gauge is included;

[0021] The pressure gauge is arranged on the oil circuit between the P end of the non-leakage pressure-maintaining valve and the accumulator.

[0022] Furthermore, M=3, N=3.

[0023] Furthermore, the model of the retreat-type lever clamping cylinder is LFA0480-CC;

[0024] The model of the single-acting rotary clamping cylinder is LG0481-CL.

[0025] Further, the model of the leak-free stop valve is BT2210-0;

[0026] The model of the non-leakage pressure-maintaining valve is BEQ0220-0GB.

[0027] Furthermore, the model of the pressure gauge is G60LM-10-MP-1-10.

[0028] Compared with the prior art, the utility model has the following beneficial effects:

[0029] The utility model provides a linkage hydraulic clamp, which adopts a single-acting rotary clamping cylinder and a retreating lever clamping cylinder to clamp the end face of the workpiece, and the processing accuracy of the parts is more stable; the retreating lever clamping cylinder can realize that after the end face is processed, the pressure plate on it is extended to below the positioning surface of the clamp to prepare for external circle processing. The structural characteristics of the single-acting rotary clamping cylinder and the retreating lever clamping cylinder are utilized to design a linkage hydraulic circuit, and the switching between the pressure plates is realized by controlling the filling direction of the hydraulic oil. The processing of the workpiece can be completed without manually replacing the pressure plate, which can greatly improve the clamping efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a schematic diagram of the structure of the workpiece;

[0031] Figure 2 It is a schematic diagram of the structure of an embodiment of the utility model;

[0032] Figure 3 for Figure 2 Left view of

[0033] Figure 4 It is a hydraulic principle diagram of an embodiment of the utility model;

[0034] The following are the descriptions of the reference numerals:

[0035] 1- fixture body, 2- non-leakage stop valve, 3- non-leakage pressure-maintaining valve, 4- first pressure plate, 5- retractable lever clamping cylinder, 6- single-acting rotary clamping cylinder, 7- second pressure plate, 8- pressure gauge, 9- accumulator, 10- workpiece. DETAILED DESCRIPTION

[0036] In order to make the purpose, advantages and features of the present invention more clear, a linkage hydraulic clamp proposed by the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0037] A linkage hydraulic clamp, such as Figure 2 , Figure 3As shown, the fixture body 1 includes a non-leakage stop valve 2, a non-leakage pressure-maintaining valve 3, three first pressing plates 4, three retractable lever clamping cylinders 5, three single-acting rotary clamping cylinders 6, three second pressing plates 7, a pressure gauge 8 and an accumulator 9. The fixture body 1 is provided with a positioning surface in contact with the bottom surface of the workpiece 10 for oil circuit arrangement and other workpiece placement.

[0038] The three retractable lever clamping cylinders 5 and the three single-acting rotary clamping cylinders 6 are evenly distributed on the fixture body 1 along the circumference, and the three single-acting rotary clamping cylinders 6 are located on the inner side of the circumference of the three retractable lever clamping cylinders 5. The retractable lever clamping cylinder 5 is located on the outer side of the workpiece 10, and the single-acting rotary clamping cylinder 6 is located in the inner hole of the workpiece 10. The three first pressing plates 4 are respectively arranged on the three retractable lever clamping cylinders 5, and are used to cooperate with the retractable lever clamping cylinders 5 to realize the end face pressing of the workpiece 10 from the inside, and the first pressing plates 4 are located below the positioning surface in the non-clamping state. The three second pressing plates 7 are respectively arranged on the three single-acting rotary clamping cylinders 6, and are used to cooperate with the single-acting rotary clamping cylinders 6 to realize the end face pressing of the workpiece 10 from the outside. The retractable lever clamping cylinder 5 can provide a stable and reliable pressing force, and its clamping and non-clamping states are controlled by the filling direction of the hydraulic oil. The single-acting rotary clamping cylinder 6 can provide a stable and reliable clamping force. It clamps when filled with hydraulic oil, and is in a non-clamping state under the action of an internal spring when not filled with hydraulic oil.

[0039] like Figure 4 As shown, the non-leakage pressure-maintaining valve 3 is used to connect the oil pressure source, the P end of the non-leakage pressure-maintaining valve 3 is connected to the oil inlet of the single-acting rotary clamping cylinder 6 and the release oil pressure end of the retreating lever clamping cylinder 5, and the R end is connected to the clamping oil pressure end of the retreating lever clamping cylinder 5. The non-leakage pressure-maintaining valve 3 is used to connect the oil pressure source, and the clamp can be disconnected from the oil pressure source under the pressure-maintaining state. The non-leakage stop valve 2 is arranged on the oil circuit between the P end of the non-leakage pressure-maintaining valve 3 and the oil inlet of the single-acting rotary clamping cylinder 6, and the non-leakage stop valve 2 is used to control the flow direction of the hydraulic oil. The pressure gauge 8 and the accumulator 9 are arranged in turn on the oil circuit between the P end of the non-leakage pressure-maintaining valve 3 and the oil inlet of the single-acting rotary clamping cylinder 6 and the release oil pressure end of the retreating lever clamping cylinder 5, and the accumulator 9 is close to the front end of the non-leakage stop valve 2. The pressure gauge 8 is used to display the pressure of the oil circuit, and the accumulator 9 is used to prevent pressure release. In this embodiment, the model of the retractable lever clamping cylinder 5 is LFA0480-CC, the model of the single-acting rotary clamping cylinder 6 is LG0481-CL, the model of the non-leakage stop valve 2 is BT2210-0, the model of the non-leakage pressure maintaining valve 3 is BEQ0220-0GB, the model of the pressure gauge 8 is G60LM-10-MP-1-10, and the accumulator 9 is a spring accumulator, model JSS5050-HG.

[0040] The working principle of a linkage hydraulic clamp provided in this embodiment is:

[0041] ①Before use, place the non-leakage stop valve 2 in the normally closed state;

[0042] ② Add oil to the P end of the non-leakage pressure-maintaining valve 3 and return oil to the R end. Under the action of the oil pressure, the retractable lever clamping cylinder 5 is placed in a non-clamping state. The single-acting rotary clamping cylinder 6 is also in a non-clamping state under the action of the internal spring. The workpiece 10 can be placed on the positioning surface of the fixture body 1 and prepared for processing;

[0043] ③ Keep the P end of the non-leakage pressure-maintaining valve 3 filled with oil and the R end returning oil, and put the non-leakage stop valve 2 in the normally open state. At this time, the hydraulic oil enters the single-acting rotary clamping cylinder 6 to make it move and clamp the workpiece 10. At this time, the outer circle and part of the end face of the workpiece 10 can be processed. When the retreat lever clamping cylinder 5 is in the non-clamping state, the first pressure plate 4 on it will drop below the positioning surface of the workpiece 10, which will not affect the outer circle processing;

[0044] ④ After machining the outer circle and part of the end face, place the non-leakage stop valve 2 in the normally closed state, adjust the oil inlet sequence, so that the R end of the non-leakage pressure-maintaining valve 3 is filled with oil and the P end is returned. Under the action of oil pressure, the retreat lever clamping cylinder 5 is placed in the clamping state, and then the non-leakage stop valve 2 is placed in the normally open state. Under the action of the internal spring of the single-acting rotary clamping cylinder 6, the hydraulic oil is returned from the P end of the non-leakage pressure-maintaining valve 3. At this time, the single-acting rotary clamping cylinder 6 is in a non-clamping state and the retreat lever clamping cylinder 5 is in a clamping state. The remaining end face of the workpiece can be machined. The action of the non-leakage stop valve 2 is to avoid the two clamping cylinders being in a relaxed state at the same time to prevent the workpiece 10 from moving without being clamped;

[0045] ⑤ Place the non-leakage stop valve 2 in the normally closed state, adjust the oil inlet sequence, so that the P end of the non-leakage pressure maintaining valve 3 is filled with oil and the R end is returned with oil. Under the action of oil pressure, the retreat lever clamping cylinder 5 is placed in the non-clamping state. At this time, both clamping cylinders are in the non-clamping state, and the processed workpiece 10 can be removed and the unprocessed workpiece 10 can be installed.

[0046] In ①②③④⑤ of the above process, the actions of the non-leakage pressure-maintaining valve 3 and the non-leakage stop valve 2 can be realized through program control.

[0047] The linkage hydraulic clamp provided by this embodiment is reliable and stable, and the precision of parts is more stable. It can reduce the time of loading and unloading workpieces, improve processing efficiency, and the pressure plates can move with each other during vertical lathe processing.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solution described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solution to deviate from the scope of the technical solution of the utility model.

Claims

1. A linkage hydraulic clamp, characterized in that: The clamp comprises a clamp body (1), and a leak-free stop valve (2), a leak-free pressure-maintaining valve (3), M first pressing plates (4), M retractable lever clamping cylinders (5), N single-acting rotary clamping cylinders (6), and N second pressing plates (7) arranged on the clamp body (1), wherein M and N are both integers greater than or equal to 2; The clamp body (1) is provided with a positioning surface on the top thereof, the positioning surface being in contact with the bottom surface of the workpiece (10); The M retractable lever clamping cylinders (5) and the N single-acting rotary clamping cylinders (6) are evenly distributed on the clamp body (1) along the circumference, and the N single-acting rotary clamping cylinders (6) are located on the inner side of the circumference of the M retractable lever clamping cylinders (5); the retractable lever clamping cylinder (5) is located on the outer side of the workpiece (10), and the single-acting rotary clamping cylinder (6) is located in the inner hole of the workpiece (10); The M first pressing plates (4) are respectively arranged on the M retreat-type lever clamping cylinders (5) and are used to cooperate with the retreat-type lever clamping cylinders (5) to realize end surface clamping of the workpiece (10) from the inside, and in the non-clamping state, the first pressing plates (4) are located below the positioning surface; The N second pressing plates (7) are respectively arranged on the N single-acting rotary clamping cylinders (6) and are used to cooperate with the single-acting rotary clamping cylinders (6) to achieve end surface clamping of the workpiece (10) from the outside; The non-leakage pressure-maintaining valve (3) is used to connect to an oil pressure source, the P end of the non-leakage pressure-maintaining valve (3) is connected to the oil inlet of the single-acting rotary clamping cylinder (6) and the release oil pressure end of the retreating lever clamping cylinder (5), and the R end is connected to the clamping oil pressure end of the retreating lever clamping cylinder (5); The non-leakage stop valve (2) is arranged on the oil circuit between the P end of the non-leakage pressure-maintaining valve (3) and the oil inlet of the single-acting rotary clamping cylinder (6).

2. A linkage hydraulic clamp according to claim 1, characterized in that: Also included is an accumulator (9) for preventing pressure relief; The accumulator (9) is arranged on the oil circuit between the P end of the non-leakage pressure-maintaining valve (3), the oil inlet of the single-acting rotary clamping cylinder (6), and the release oil pressure end of the retreat lever clamping cylinder (5).

3. A linkage hydraulic clamp according to claim 2, characterized in that: The energy accumulator (9) is a spring type energy accumulator.

4. The linkage hydraulic clamp according to claim 3, characterized in that: The model of the accumulator (9) is JSS5050-HG.

5. A linkage hydraulic clamp according to any one of claims 2 to 4, characterized in that: Also includes a pressure gauge (8); The pressure gauge (8) is arranged on the oil circuit between the P end of the non-leakage pressure-maintaining valve (3) and the accumulator (9).

6. The linkage hydraulic clamp according to claim 5, characterized in that: The M=3, N=3.

7. The linkage hydraulic clamp according to claim 6, characterized in that: The model of the retreat-type lever clamping cylinder (5) is LFA0480-CC; The model of the single-acting rotary clamping cylinder (6) is LG0481-CL.

8. The linkage hydraulic clamp according to claim 7, characterized in that: The model of the non-leakage stop valve (2) is BT2210-0; The model of the non-leakage pressure-maintaining valve (3) is BEQ0220-0GB.

9. The linkage hydraulic clamp according to claim 8, characterized in that: The model of the pressure gauge (8) is G60LM-10-MP-1-10.

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