Safety module for double-acting actuating mechanism

Abstract

The safety module comprises an oil inlet main path and an oil return main path, the oil inlet main path is used for being communicated with a rodless cavity of the double-acting actuating mechanism, the oil return main path is used for being communicated with a rod cavity of the double-acting actuating mechanism, the safety module further comprises a plurality of electromagnetic valves, oil inlets of the electromagnetic valves are all communicated with the oil inlet main path, and oil outlets of the electromagnetic valves are communicated with the oil return main path. Oil return ports of the plurality of electromagnetic valves are communicated with the oil return main path; an oil outlet of each electromagnetic valve is connected with inlets of any two different shuttle valves at the same time, so that it is ensured that when any electromagnetic valve is powered off, hydraulic oil normally enters the corresponding two-way valve from each shuttle valve, and control ports of the two-way valves communicate with outlets of the shuttle valves in a one-to-one correspondence mode; and two side ports of the plurality of two-way valves are respectively communicated with the rodless cavity and the rod cavity. Quick action control over the double-acting executing mechanism is achieved through power loss of any two electromagnetic valves, and loss caused by faults of a single electromagnetic valve is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of double-acting actuators, and particularly to a safety module for a double-acting actuator. Background Art

[0002] In an industrial hydraulic system, the working conditions of a double-acting actuator generally include normal working conditions and fast-action working conditions. In normal working conditions, the reciprocating movement of the internal piston is achieved by inputting / discharging hydraulic oil into / from the rodless cavity and the rod cavity of the double-acting actuator. In fast-action working conditions, the rodless cavity and the rod cavity of the double-acting actuator need to be connected to each other to balance the oil pressure on both sides, and the internal piston of the double-acting actuator relies on its internal elastic member to reset. In the prior art, generally, a single solenoid valve is used to control a single two-way valve to connect or cut off the rodless cavity and the rod cavity of the double-acting actuator. The defect of this solution is that when a single solenoid valve loses power due to a fault, the two-way valve will connect the rodless cavity and the rod cavity of the double-acting actuator to each other, thereby causing the fast-action working condition of the double-acting actuator to be mis-started, resulting in losses. Therefore, the stability of the operating conditions of the entire system is relatively low. Summary of the Invention

[0003] In view of the deficiencies of the prior art, the present invention provides a safety module for a double-acting actuator. The safety module avoids losses caused by a single solenoid valve failure by controlling the fast action of the double-acting actuator when any two solenoid valves lose power, and improves the stability of the operation of the entire safety module.

[0004] The present invention is realized through the following technical solutions:

[0005] A safety module for a double-acting actuator includes an oil inlet main path and an oil return main path. The oil inlet main path is used to connect the rodless cavity of the double-acting actuator, and the oil return main path is used to connect the rod cavity of the double-acting actuator. The safety module further includes:

[0006] A plurality of solenoid valves, including a first solenoid valve, a second solenoid valve, and a third solenoid valve. The oil inlets of the plurality of solenoid valves are all connected to the oil inlet main path, and the oil outlets of the plurality of solenoid valves are all connected to the oil return main path;

[0007] A plurality of shuttle valves, including a first shuttle valve, a second shuttle valve, and a third shuttle valve. The oil outlet of the first solenoid valve is simultaneously connected to the first inlet of the first shuttle valve and the first inlet of the third shuttle valve. The oil outlet of the second solenoid valve is simultaneously connected to the second inlet of the first shuttle valve and the first inlet of the second shuttle valve. The oil outlet of the third solenoid valve is simultaneously connected to the second inlet of the second shuttle valve and the second inlet of the third shuttle valve;

[0008] Multiple two-way valves, including a first two-way valve, a second two-way valve, and a third two-way valve. The control port of the first two-way valve is communicated with the outlet of the first shuttle valve. The control port of the second two-way valve is communicated with the outlet of the third shuttle valve. The control port of the third two-way valve is communicated with the outlet of the second shuttle valve. Both side ports of the first two-way valve, the second two-way valve, and the third two-way valve are respectively communicated with the rodless cavity and the rod chamber.

[0009] Further, an oil inlet branch and an oil return branch are further included. The oil inlet branch is communicated with the main oil inlet path, and the oil return branch is communicated with the main oil return path. The oil inlet ports of the multiple solenoid valves are all communicated with the oil inlet branch, and the oil return ports of the multiple solenoid valves are all communicated with the oil return branch.

[0010] Further, the pipeline distance between the first inlet of the shuttle valve and the oil inlet port P of the main oil inlet path is not equal to the pipeline distance between the second inlet of the shuttle valve and the oil inlet port P of the main oil inlet path.

[0011] Further, a first branch and a second branch are further included. The first branch is communicated with the rod chamber, and the second branch is communicated with the rodless cavity. Both side ports of the first two-way valve, the second two-way valve, and the third two-way valve are respectively communicated with the first branch and the second branch.

[0012] Further, the multiple two-way valves further include a fourth two-way valve. The control port of the fourth two-way valve is communicated with the outlet of the first shuttle valve. One side port of the fourth two-way valve is communicated with the second branch, and the other side port is communicated with the main oil return path.

[0013] Further, the multiple two-way valves further include a fifth two-way valve. The control port of the fifth two-way valve is communicated with the outlet of the second shuttle valve. One side port of the fifth two-way valve is communicated with the second branch, and the other side port is communicated with the main oil return path.

[0014] Further, the multiple two-way valves further include a sixth two-way valve. The control port of the sixth two-way valve is communicated with the outlet of the third shuttle valve. One side port of the sixth two-way valve is communicated with the second branch, and the other side port is communicated with the main oil return path.

[0015] Further, the first solenoid valve, the second solenoid valve, and the third solenoid valve are all two-position three-way solenoid valves.

[0016] Compared with the prior art, the advantages of the present invention are as follows:

[0017] In the safety module provided by the present application, when a single solenoid valve loses power due to a fault, the normal operating condition of the double-acting actuator can still be ensured. Only when two or three solenoid valves fail simultaneously will it lead to the mis-start of the control loop and the fast-acting condition, greatly reducing the probability of mis-start, avoiding losses caused by a single solenoid valve failure, and improving the working stability of the entire safety module. Description of the Drawings

[0018] Figure 1 It is a schematic diagram of a safety module for a double-acting actuator according to an embodiment of the present invention.

[0019] 1. Main oil inlet path; 11. Oil inlet branch; 12. First branch; 2. Main oil return path; 21. Oil return branch; 22. Second branch; 3. Hydraulic actuator; 30. Rodless cavity; 31. Rod chamber; 32. Piston; 33. Elastic member; 41. First solenoid valve; 42. Second solenoid valve; 43. Third solenoid valve; 51. First shuttle valve; 52. Second shuttle valve; 53. Third shuttle valve; 61. First two-way valve; 62. Second two-way valve; 63. Third two-way valve; 64. Fourth two-way valve; 65. Fifth two-way valve; 66. Sixth two-way valve. Detailed Description of the Preferred Embodiment

[0020] The technical solution of the invention will be further described in detail and non-limitingly below in conjunction with the preferred embodiment and its drawings. In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention and should not be construed as a limitation of the present invention.

[0021] As Figure 1As shown in the figure, a safety module for a double-acting actuator according to an embodiment of the present invention includes an oil inlet main path 1, an oil return main path 2, a plurality of solenoid valves, a plurality of shuttle valves, and a plurality of two-way valves. The oil inlet main path 1 is used to communicate with the rodless cavity 30 of the double-acting actuator 3, and the oil return main path 2 is used to communicate with the rod cavity 31 of the double-acting actuator 3. The plurality of solenoid valves include a first solenoid valve 41, a second solenoid valve 42, and a third solenoid valve 43. The oil inlet ports of the plurality of solenoid valves are all communicated with the oil inlet main path 1, and the oil return ports of the plurality of solenoid valves are all communicated with the oil return main path 2. The plurality of shuttle valves include a first shuttle valve 51, a second shuttle valve 52, and a third shuttle valve 53. The oil outlet of the first solenoid valve 41 is simultaneously communicated with the first inlet of the first shuttle valve 51 and the first inlet of the third shuttle valve 53. The oil outlet of the second solenoid valve 42 is simultaneously communicated with the second inlet of the first shuttle valve 51 and the first inlet of the second shuttle valve 52. The oil outlet of the third solenoid valve 43 is simultaneously communicated with the second inlet of the second shuttle valve 52 and the second inlet of the third shuttle valve 53. The plurality of two-way valves include a first two-way valve 61, a second two-way valve 62, and a third two-way valve 63. The control port of the first two-way valve 61 is communicated with the outlet of the first shuttle valve 51. The control port of the second two-way valve 62 is communicated with the outlet of the third shuttle valve 53. The control port of the third two-way valve 63 is communicated with the outlet of the second shuttle valve 52. The two side ports of the first two-way valve 61, the second two-way valve 62, and the third two-way valve 63 are respectively communicated with the rodless cavity 30 and the rod cavity 31.

[0022] In this embodiment, the double-acting actuator has a function of spring reset and can be selected as normally open type and normally closed type according to the working conditions. When the double-acting actuator is in a fast-action working condition, the oil pressures on both sides of the rod cavity 31 and the rodless cavity 30 are balanced, and the piston 32 inside the double-acting actuator is reset by the elastic member 33. In this embodiment, the piston 32 is located at the rightmost side of the cavity under the action of the elastic member 33, so that the double-acting actuator continuously maintains the fast-action working condition.

[0023] The safety module further includes an oil inlet branch 11 and an oil return branch 21. The oil inlet branch 11 is communicated with the oil inlet main path 1, and the oil return branch 21 is communicated with the oil return main path 2. The oil inlet ports of the plurality of solenoid valves are all communicated with the oil inlet branch 11, and the oil return ports of the plurality of solenoid valves are all communicated with the oil return branch 21.

[0024] The pipeline distance between the first inlet of the shuttle valve and the oil inlet P of the oil inlet main path 1 is not equal to the pipeline distance between the second inlet of the shuttle valve and the oil inlet P of the oil inlet main path 1, so as to prevent the two inlets of the same shuttle valve from being oiled simultaneously, resulting in abnormal oil outlet at the outlet of the shuttle valve.

[0025] The safety module further includes a first branch 12 and a second branch 22. The first branch 12 is communicated with the rod cavity 31, and the second branch 22 is communicated with the rodless cavity 30. The two side ports of the first two-way valve 61, the second two-way valve 62, and the third two-way valve 63 are respectively communicated with the first branch 12 and the second branch 22.

[0026] The multiple two-way valves further include a fourth two-way valve 64, a fifth two-way valve 65 and a sixth two-way valve 66. The control port of the fourth two-way valve 64 is communicated with the outlet of the first shuttle valve 51. One side port of the fourth two-way valve 64 is communicated with the second branch 22, and the other side port is communicated with the main oil return path 2. The control port of the fifth two-way valve 65 is communicated with the outlet of the second shuttle valve 52. One side port of the fifth two-way valve 65 is communicated with the second branch 22, and the other side port is communicated with the main oil return path 2. The control port of the sixth two-way valve 66 is communicated with the outlet of the third shuttle valve 53. One side port of the sixth two-way valve 66 is communicated with the second branch 22, and the other side port is communicated with the main oil return path 2. The purpose of setting the fourth two-way valve 64, the fifth two-way valve 65 and the sixth two-way valve 66 is to discharge the excess hydraulic oil. Refer to Figure 1 , when the double-acting actuator 3 is in the fast-action state, when the piston rod moves to the right, the space of the rodless cavity 30 becomes smaller. The hydraulic oil discharged from the rodless cavity 30 flows back to the rod cavity 31 through the first two-way valve 61 and / or the second two-way valve 62 and / or the third two-way valve 63. Since the piston rod occupies a certain space in the rod cavity 31, therefore, the rod cavity 31 can only receive part of the hydraulic oil discharged from the rodless cavity 30, and the excess hydraulic oil flows back to the main oil return path 2 through the fourth two-way valve 64 and / or the fifth two-way valve 65 and / or the sixth two-way valve 66.

[0027] In this embodiment, the first solenoid valve 41, the second solenoid valve 42 and the third solenoid valve 43 are all two-position three-way solenoid valves.

[0028] The working principle of the present invention is as follows:

[0029] Under normal conditions, the first solenoid valve 41, the second solenoid valve 42 and the third solenoid valve 43 are all in the energized state. The hydraulic oil flows through the first solenoid valve 41, the second solenoid valve 42 and the third solenoid valve 43 respectively to the corresponding shuttle valves, and flows out from the outlets of the shuttle valves. The hydraulic oil flowing out from the shuttle valves flows to the control ports of the corresponding two-way valves respectively, so that the two-way valves are in the blocked state, that is, the two side ports of the two-way valve are not communicated with each other. At this time, the hydraulic oil enters from the oil inlet P port, passes through the main oil inlet path 1 to reach the rodless cavity 30, and the hydraulic oil discharged from the rod cavity 31 is discharged from the oil drain port T port through the main oil return path 2.

[0030] When any one of the three solenoid valves is de-energized, there is still hydraulic oil passing through the three shuttle valves, and the three two-way valves are still in the blocked state. The working state of the double-acting actuator 3 remains unchanged, and the double-acting actuator 3 is still in the normal working state.

[0031] When two or more of the three solenoid valves are in the de-energized state, assuming that the first solenoid valve 41 and the second solenoid valve 42 are in the de-energized state, the hydraulic oil only flows out from the third solenoid valve 43. At this time, only the second shuttle valve 52 and the third shuttle valve 53 connected to the third solenoid valve 43 have hydraulic oil flowing out. At this time, the second two-way valve 62 and the third two-way valve 63 are in the blocked state, and the first two-way valve 61 is in the connected state. At this time, the rodless chamber 30 and the rod chamber 31 of the double-acting actuator 3 are connected through the first two-way valve 61. At this time, the oil pressure on both sides is balanced, and the double-acting actuator 3 resets the piston close to its internal elastic part, so that the double-acting actuator 3 is in a fast action state.

[0032] The beneficial effects of the present invention are as follows:

[0033] When a single solenoid valve loses power due to a fault, the normal working condition of the double-acting actuator can still be guaranteed. Only when two or three solenoid valves fail at the same time will the control circuit be mistakenly started and quickly operated. This greatly reduces the probability of false start-up, avoids losses caused by a single solenoid failure, and improves the stability of the entire safety module.

[0034] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A safety module for a double-acting actuator, comprising an oil inlet main passage (1) and an oil return main passage (2), the oil inlet main passage (1) being used for connecting the rodless cavity (30) of the double-acting actuator (3), and the oil return main passage (2) being used for connecting the rod cavity (31) of the double-acting actuator (3), characterized in that, It further includes: A plurality of solenoid valves, including a first solenoid valve (41), a second solenoid valve (42), and a third solenoid valve (43). The oil inlets of the plurality of solenoid valves are all communicated with the main oil inlet path (1), and the oil return ports of the plurality of solenoid valves are all communicated with the main oil return path (2); A plurality of shuttle valves, including a first shuttle valve (51), a second shuttle valve (52), and a third shuttle valve (53). The oil outlet of the first solenoid valve (41) is simultaneously communicated with the first inlet of the first shuttle valve (51) and the first inlet of the third shuttle valve (53). The oil outlet of the second solenoid valve (42) is simultaneously communicated with the second inlet of the first shuttle valve (51) and the first inlet of the second shuttle valve (52). The oil outlet of the third solenoid valve (43) is simultaneously communicated with the second inlet of the second shuttle valve (52) and the second inlet of the third shuttle valve (53); A plurality of two-way valves, including a first two-way valve (61), a second two-way valve (62), and a third two-way valve (63). The control port of the first two-way valve (61) is communicated with the outlet of the first shuttle valve (51). The control port of the second two-way valve (62) is communicated with the outlet of the third shuttle valve (53). The control port of the third two-way valve (63) is communicated with the outlet of the second shuttle valve (52). The two side ports of the first two-way valve (61), the second two-way valve (62), and the third two-way valve (63) are respectively communicated with the rodless cavity (30) and the rod chamber (31); 2. The security module according to claim 1, characterized in that, It further includes an oil inlet branch (11) and an oil return branch (21). The oil inlet branch (11) is communicated with the main oil inlet path (1), and the oil return branch (21) is communicated with the main oil return path (2). The oil inlets of the plurality of solenoid valves are all communicated with the oil inlet branch (11), and the oil return ports of the plurality of solenoid valves are all communicated with the oil return branch (21).

3. The security module according to claim 2, characterized in that, The pipeline distance between the first inlet of the shuttle valve and the oil inlet P of the main oil inlet path (1) is not equal to the pipeline distance between the second inlet of the shuttle valve and the oil inlet P of the main oil inlet path (1).

4. The security module according to claim 2, characterized in that, It further includes a first branch (12) and a second branch (22). The first branch (12) is communicated with the rod chamber (31), and the second branch (22) is communicated with the rodless cavity (30). The two side ports of the first two-way valve (61), the second two-way valve (62), and the third two-way valve (63) are respectively communicated with the first branch (12) and the second branch (22).

5. The security module according to claim 4, characterized in that, The plurality of two-way valves further includes a fourth two-way valve (64). The control port of the fourth two-way valve (64) is communicated with the outlet of the first shuttle valve (51). One side port of the fourth two-way valve (64) is communicated with the second branch (22), and the other side port is communicated with the main oil return path (2).

6. The security module according to claim 4, characterized in that, The plurality of two-way valves further includes a fifth two-way valve (65). The control port of the fifth two-way valve (65) is communicated with the outlet of the second shuttle valve (52). One side port of the fifth two-way valve (65) is communicated with the second branch (22), and the other side port is communicated with the main oil return path (2).

7. The security module according to claim 4, characterized in that, The plurality of two-way valves further includes a sixth two-way valve (66), a control port of the sixth two-way valve (66) is communicated with an outlet of the third shuttle valve (53), one side port of the sixth two-way valve (66) is communicated with the second branch (22), and the other side port is communicated with the main oil return path (2).

8. The security module according to claim 7, characterized in that The first solenoid valve (41), the second solenoid valve (42) and the third solenoid valve (43) are all two-position three-way solenoid valves.

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