CN86104051A - Hydraulic operating mechanism - Google Patents

Abstract

A hydraulically operated mechanism in which a differential piston is used as the drive member, wherein the differential piston is driven by a hydraulic control mechanism by high pressure fluid applied to the face of the large piston, and the high pressure fluid is always applied to the face of the small piston. The structure of the hydraulic operating mechanism is arranged in such a way that when the differential piston stops at its return position, the high-pressure fluid acts on the two piston surfaces at the same time, and the thrust generated by the force difference applied to the two piston surfaces is acted on Gripped by the gripping mechanism on the differential piston or its extension. Once the grip force of the grip mechanism is released, the differential piston moves forward; once the high pressure fluid acting on the face side of the large piston is released, the piston moves backward.

Description

Hydraulic operating mechanism

The present invention relates to a hydraulic operating mechanism suitable for use in an apparatus for driving a load at a high speed upon receiving an operating command.

Pneumatic pressure, such as pneumatic pressure, and hydraulic pressure, such as oil pressure, have heretofore been used as drive sources for equipment that moves linearly or rotationally at high speeds, while pneumatic operating mechanisms are often used for lighter loads.

However, when a heavy load, for example, a load weighing several tons, is operated, the pneumatic operating mechanism inevitably becomes large, and a great deal of noise is inevitably generated due to the supply and discharge of air during the operation, and therefore, the cost for maintaining the air compressor for increasing the air pressure inevitably increases, so that the hydraulic operating system is mostly used.

The hydraulic operating mechanism can easily obtain a high pressure as compared with the pneumatic system because the fluid used has a relatively non-compressible property, so that the noise at the time of operation is low, the mechanism can be made small, and excellent response can be obtained at the time of high-speed operation.

In a hydraulically operated system, if air is mixed into the hydraulic fluid during assembly of the mechanism, or if air is dissolved in the fluid during compression of the fluid, such air in the fluid slows the response by the mechanism and the operating time does not remain constant.

A typical example of such a high speed mechanism is a switching mechanism for a power transmission system.

As the capacity and voltage of power transmission systems increase, switches, and particularly power interrupters, are more in need of improving their characteristics. For this purpose, not only gas-insulated interrupters are used, in which SF is used₆(sulphur hexafluoride) gas acts as an arc-extinguishing medium and it is desirable to improve the performance, improve the stability of the system, for example increase the switching speed, reduce the switching time difference. In addition, maintenance problems that reduce the time of use, such as improved maintenance of the mechanism and reduced noise generation, are also increasingly required.

Although the present invention has been described in terms of a power switch operating mechanism, the present invention is applicable to other similar high speed operating mechanisms.

Fig. 1 schematically shows a conventional hydraulic operating mechanism disclosed in japanese patent laid-open No.57-111915, wherein [101] is a switching device such as an interrupter switching member. The switching member [101] includes a fixed contact [102] and a movable contact [103] and is driven by a driving mechanism [104] to open or close the contacts. The drive mechanism [104] includes a differential piston [106] connected to the movable contact [103] by a rod [105], a hydraulic cylinder [107], the differential piston [106] being hydraulically sealed between them within the hydraulic cylinder [107] by a seal [106a ]. A conduit (108) connected to an end face (large cross-sectional side) [107a ] of the conduit (107) is connected to a hydraulic control device (109), and the hydraulic control device (109) is connected to a low pressure tank (110) by a low pressure conduit (111). The accumulator [113] is connected to the rod side (small cross-sectional side) [107b ] of the cylinder [107] by a passage [112], and a high-pressure conduit [114] connects the accumulator [113] to the hydraulic control apparatus [109 ]. Furthermore, a pump device [115] for supplying a high-pressure fluid is provided so as to recover the fluid discharged into the low-pressure tank [110] through a conduit [117 ]. Another conduit [116] is used to supply high pressure to the accumulator [113] through it.

The operation of the general mechanism described above will now be discussed. High pressure fluid from the accumulator [113] is often provided through a passage [112] on the rod side [107a ] of the differential piston [106 ]. When an operation command to open the switch member [101] is supplied to the hydraulic control device [109], the high-pressure fluid supplied to the end face [107a ] of the differential piston [106] through the conduit [114] is discharged into the low-pressure tank [110] through the conduits [108] and [111 ]. At this time, the passage for supplying the high-pressure fluid to the guide pipe [108] is closed. Thus, high pressure fluid on the rod side [107b ] of the differential piston [106] pushes down the differential piston [106], opening the switch member [101] as shown in FIG. 1. In this state, since the end face [107a ] of the differential piston containing the conduit [108] is filled with low pressure fluid, the seal [106a ] of the piston [106] must have good sealing properties in order to achieve ideally no fluid leakage between the high and low pressure fluids.

When an operation command to close the opening and closing member [101] supplies the hydraulic control device [109], a communication passage connecting from the conduit [108] to the low pressure conduit [111] is closed, and at the same time, a supply passage supplying the high pressure fluid to the conduit [108] is opened, so that the conduit [108] is communicated with the high pressure conduit [114 ]. As a result, high-pressure fluid is supplied to both the end surface [107a ] and the rod side [107b ] of the differential piston [106], and the piston [106] is moved upward by a thrust force generated by an area difference between the end surface and the rod side, thereby closing the switching member [101 ]. When the switch member [101] is closed, the conduit [108] is filled with high pressure fluid.

In order to solve the above problem, there is provided a hydraulic operation mechanism which is arranged such that: unless an operating command is issued, the hydraulic pressure applied to the large piston side of the piston end face is always high.

In addition to this, the operating mechanism as a chopper must have a so-called "anti-bounce function". For example, when an interruption command is issued for the purpose of trouble-shooting a power system and at the same time a shutdown command is issued manually to an interrupter, the simultaneous excitation prevention function (usually a circuit configuration) is activated, so that the interruption operation is completed after completion of the closing operation. At this point, if the closing instruction is still present after the completion of the interrupting action, the interrupter is reclosed, so there is still a possibility that a fault exists in the power system. This phenomenon is called a jumping operation and should be prevented by electrical or mechanical measures.

Fig. 2 and 3 show cross-sectional views of a typical hydraulic actuator. In the figure, [1] is a switch contact connected to a driving member [6] through a rod [2], thereby completing closing and interrupting operations. The driving part comprises a differential piston [3] for driving the contact [1], a sealing member [3a ], a hydraulic cylinder [5] and buffer cylinder rings [4a ] and [4b ]. The actuating member is operated by a main valve [7] and high pressure fluid is provided through an amplification valve [8 ]. The high-pressure fluid is supplied from an accumulator [9], and the accumulator [9] is always kept at a predetermined pressure by a pump not shown in the figure.

High-pressure fluid from an accumulator (9) is fed through a conduit (10) to a small chamber (5 a) in the cylinder (5) above the small piston face and is further supplied to a main valve (7) through a conduit (11).

The main valve [7] includes an evacuation valve [14], a supply valve [13] which are opposed to each other, and a spring [13a ]. The pilot chamber [15] of the purge valve [14] is subjected to high pressure fluid introduced from the amplification valve [8] through conduit [16 ]. As a result, the supply valve [13] and the exhaust valve [14] operate together, and function as a main valve [7] that is opened and closed. That is, when the high-pressure fluid does not act on the pilot chamber [15] of the purge valve [14], it communicates with the low-pressure tank [18] through the chamber [5b ] on the large piston face of the differential piston [3 ].

On the other hand, when high-pressure fluid acts on the pilot chamber (15) of the evacuation valve (14), the chamber (5 b) of the large piston face of the differential piston (3) is connected to the accumulator (9) through a conduit (11). A conduit (45) branches from the conduit (12) to supply high pressure fluid to one side of the auxiliary supply valve (20) of the amplification valve (8). In addition, a conduit [46] directs high pressure fluid from the accumulator to the pilot chamber [21 ]. One end of the cut-off valve [38] is connected to the guide chamber [21] through a conduit [37] and a conduit [25], and the other end thereof is connected to the low-pressure tank [18] through a conduit [40 ]. The amplification valve [8] is composed of an auxiliary exhaust valve [19], an auxiliary supply valve [20] and a spring [20a ], and is subjected to the action of high-pressure fluid passing through a pilot chamber [21] of the auxiliary exhaust valve [19 ]. Therefore, the auxiliary evacuation valve [19] and the auxiliary supply valve [20] act together to open and close the amplification valve [8 ]. That is, when high-pressure liquid acts on the pilot chamber [21], the conduit [16] is connected to the accumulator [9] through the conduit [45 ]. On the other hand, when the high-pressure liquid does not act on the guide chamber 21, the conduit 16 is connected to the low-pressure tank 18 through the conduit 22.

The interruption valve [28] is composed of a ball valve [30] and a return spring [32] and is operated by an interruption solenoid [36] which is linearly moved by an operation rod according to a command.

The guide chamber (21) of the auxiliary evacuation valve (19) is connected to the amplification valve (8) in the middle thereof through a constriction port (24) and a conduit (23), and is connected to a conduit (25). The conduit [25] is connected to one end of a shut-off valve [38] through a check valve [26] and a conduit [37] and to one end of an interruption valve [28] through a conduit [40], the interruption valve [28] being connected to the low-pressure tank [18] through a conduit [27 ].

The shut valve (38) and the cut-off valve (28) are composed of ball valves (29) and (30), return springs (31) and (32), respectively, and operated by solenoid devices (35) and (36) linearly moved according to a command through operation rods (33) and (34). The electromagnetic device is composed of movable iron cores [35a ] and [36a ] and fixed coils [35b ] and [36b ].

In the interrupted state of the hydraulic mechanism of the above-described construction shown in FIG. 2, when a closing command is given to the solenoid unit [35], the movable iron core [35a ] is driven, and the closing valve [38] is pushed by the operating rod [33], thereby opening the ball valve [29 ]. This allows high pressure fluid to pass through the check valve [26] and conduit [25] from the conduit [37] to the pilot chamber [21] of the auxiliary exhaust valve [19 ]. The action of the high pressure fluid moves the auxiliary exhaust valve [19] of the amplification valve [8] downwardly to close a conduit [22] connected to the low pressure tank [18] and open an auxiliary supply valve [20] opposite the conduit [22 ]. This allows high pressure fluid to pass through the conduit [12], conduit [45] and conduit [16] to the pilot chamber [15] of the dump valve [14] to switch the main valve [7 ]. In this case, the new position described above continues even when the shut-off valve [38] is reset, since high pressure fluid is applied through the conduits [45] and [23] and the constriction [24 ]. When high pressure fluid acts on the pilot chamber [15], the exhaust valve [14] closes the conduit [17] connected to the low pressure tank [18], while the opposite supply valve [13] opens. As a result, the high-pressure fluid reaches the chamber [5b ] on the large area side of the differential piston [3] through the supply valve [13] and the conduit [11], and is pushed up by the force generated by the pressure difference on the receiving surface of the differential piston [3] shown in the figure to close the contact [1], as shown in FIG. 3.

When an interrupt command is given to the solenoid device (36), the movable iron core (36 a) acts on the interrupt valve (28) through the operation rod (34) to open the ball valve (30). As a result, the pilot chamber (21) of the auxiliary exhaust valve (19) of the amplification valve (8) is connected to the low pressure tank (18) through conduits (25) and (27), so that high pressure fluid is discharged. Therefore, the auxiliary discharge valve [19] of the amplification valve [8] is opened, and the auxiliary supply valve [20] is closed. To this end, a pilot chamber (15) of a drain valve (14) of a main valve (7) is connected to a low-pressure tank (18) through conduits (16) and (22), a high-pressure fluid in the pilot chamber (15) is drained, and the drain valve (14) of the main valve (7) opens a conduit (17) connected to the low-pressure tank (18) and closes an opposite supply valve (13). Then, the high-pressure fluid in the chamber [5a ] on the large piston face of the differential piston [3] is discharged through the conduit [17 ]. As a result, the differential piston [3] is pushed downward in the drawing, and the contact [1] is opened, and the state shown in fig. 2 is returned.

Although poppet valves may be substituted for the ball valves used in the above-described structures, their structures and functions are similar to those of the ball valves, and thus the description thereof will be omitted.

Since the structure of a general hydraulic operating mechanism is as described above, the conduit is a so-called high-low pulsation line in which a high pressure state and a low pressure state alternately occur. Thus, when a gas such as air is mixed or dissolved in a fluid, and when the catheter is in a high pressure state, the bubbles do not exist, and when the catheter is in a low pressure state for a long period of time, the bubbles appear in the fluid, thereby causing clogging of the high and low pressure pulsating catheter.

When high pressure fluid is again applied to the high and low pressure impulse piping under these conditions, the pressure conduction is delayed due to the compression and de-aeration of the bubbles. Therefore, the transmission of the operation signal is also slowed down, so that the closing time is not uniform.

Therefore, in such a general hydraulic operation mechanism, it is necessary to take some time to perform some preliminary operation for removing gas in the mechanism after the assembly of the mechanism. Since the preliminary operation requires a prolonged period of time, when the facility is installed in a place such as a substation and such an operation is performed thereafter, the time required for the substation to be connected to the line to recover the steady state may be too long, thereby causing some management problems of the substation.

In addition, in the closed state, the high-pressure fluid and the low-pressure fluid are tightly fluid-sealed by the seal [3a ]. If the seal [3a ] is damaged by rapid sliding, a large amount of high-pressure fluid is discharged into the low-pressure tank [18], with the result that the pressure in the accumulator [9] is rapidly decreased.

The hydraulic operating mechanism of the present invention has a structure in which a high hydraulic pressure is always maintained in a hydraulic pressure applied to a large piston side of a piston end face, not in a case where an operating command is issued. When the piston stops at its retracted position, the thrust generated by the difference between the forces exerted on the two faces of the piston is gripped by the gripping means and ceases to act.

As a result, the rod side of the differential piston does not become low pressure unless it is at the instant of operation, so that gas dissolved in the fluid does not form bubbles, thereby preventing the switching time from being inconsistent.

Fig. 1 is a schematic diagram of a general hydraulic operating mechanism.

Fig. 2 is a detailed sectional view of a general hydraulic operating mechanism in an interrupting state.

Fig. 3 is a cross-sectional view of the operating mechanism of fig. 2 in a closed state.

FIG. 4 is a schematic diagram illustrating one embodiment of the present invention in a closed state.

Fig. 5 is the same view as fig. 4 but showing an interrupted state.

Fig. 6 is a time plot illustrating the operation of the mechanism shown in fig. 4 and 5.

Fig. 7 is a cross-sectional view of an embodiment of a hydraulically operated mechanism of the present invention in an open state.

Fig. 8 is a sectional view similar to fig. 7 but showing a closed state.

Fig. 9 is a time plot illustrating the operation of the mechanism shown in fig. 7 and 8.

Fig. 10 is a cross-sectional view of one embodiment of the hydraulically operated mechanism of the present invention in a closed position.

Fig. 11 is a sectional view similar to fig. 10 but showing an opened state.

Fig. 12 is a time plot illustrating the operation of the mechanism shown in fig. 10 and 11.

Fig. 13 is a cross-sectional view of an embodiment of the main body of a hydraulically operated mechanism of the present invention.

FIG. 14 is the same as FIG. 13 but illustrates another embodiment.

Fig. 15 shows a circuit diagram of a conventional anti-jump device.

Fig. 16 is a cross-sectional view of another hydraulically operated mechanism embodiment of the present invention in a closed position.

FIG. 17 is a view showing the relationship between the trigger and the anti-trip lever when the contacts are in the closed position.

Figure 18 shows a cross-sectional view of the device of figure 16 in the contact open state.

Figure 19 is the same view as figure 17 but showing the contacts in an activated condition.

FIGS. 20 and 21 are partial cross-sectional views showing the relationship between the trigger and the anti-trip lever.

Fig. 22 is a cross-sectional view of another hydraulically operated mechanism embodiment of the present invention in an open state.

Fig. 23 is a cross-sectional view of the same watch contact as fig. 22, but in a closed state.

An embodiment of the invention will now be described with reference to the switching device shown in fig. 4 in the closed state. In the figure, 124 is a driving device which includes a differential piston 126 and a hydraulic cylinder 107.

A conduit 128 connected to an end face 107a of the cylinder 107 is connected to a hydraulic control mechanism 129, and the hydraulic control mechanism 129 is connected to a low pressure tank 110 through a low pressure conduit 111. An engagement mechanism [131] which prevents the differential piston [126] from being pushed upward when it is stuck includes a slidable engagement pivot [132] and is connected to a hydraulic control mechanism [129] through a conduit [130 ]. The engagement pivot [132] in the figure moves rightward and leftward corresponding to the engagement mechanism [131] according to the supply and discharge of the hydraulic oil.

The actual operation of the hydraulic operating mechanism according to the present invention constructed as described above will now be described with reference to the time chart shown in fig. 6. In the figure, (a) shows an on-off phase of an operation command signal, (b) shows a pressure change in the conduit [128] and the end face of the differential piston [126], (c) shows a displacement of the differential piston [126], and (d) shows a displacement of the engagement pivot [132 ].

FIG. 4 shows the closed state when the switch member [101] is turned on]At time a shown in FIG. 6 (a)₁Hydraulic control device [129]]When an operation command is given, the operation command is transmitted through the conduit [114]]Applied to a differential piston [126]]End face [107a ]]The high pressure fluid passes through the conduit (128)]And a conduit [111]]Is discharged to a low pressure tank [110]]And (4) the following steps. Due to the hydraulic control device [129]]Is so arranged as to be supplied to the conduit [128]]The high-pressure fluid is immediately stopped from being supplied, and the end surface [107a ]]Medial and catheter [128]]Instantly falls to the graph b of FIG. 6 (b)₁The low pressure is indicated by the dots. Then, the differential piston [126]]Urging its contact to point c as shown in b (c)₁To c₂Making an opening movement. At this time, since the high-pressure fluid is supplied from the hydraulic control device [129]]Through a conduit [130]]Provides a check-engagement mechanism [131]]So as to act as a differential piston [126]]Completing its action in the contact opening direction [ see point c in fig. 6 (c) ]₂]While engaging with the pivot [132]]Urging it to point d in FIG. 6 (d)₁To d₂Making a leftward movement. Differential piston [126]]And a meshing pivot [132]]The engagement therebetween is in a short time (see point d in fig. 6 (d))₂) After completion, the access conduit [128] can be opened by operating the hydraulic control device]To a low pressure tank [110]]Communicating conduits [111]]Is determined so that the differential piston [126]]End face [107a ] of]And a conduit [128]]Is connected with a high-pressure conduit [114]]Communicating, e.g. at point b in FIG. 6 (b)₂It is shown that the interior thereof is filled with a high-pressure fluid, thus assuming an interrupted state as shown in fig. 5.

When an operation command for closing the contactor is given to the hydraulic control device [129], the pressure in the conduit [130] is instantaneously dropped, and the force acting on the engaging pivot [132] is released, and the engaging pivot [132] is returned to the original state by the action of a spring not shown in the figure or by the action of a spring such as that provided in the engaging device [131 ]. At this time, since the high-pressure fluid fills the inside of the conduit [128] and the end surface [107a ] of the differential piston [126] and communicates with the conduit [114], the differential piston [126] is driven in the contact closing direction to the state shown in FIG. 1 as soon as the engagement between the engagement pivot [132] and the differential piston [126] is released. When the differential piston [126] drive is initiated, high pressure fluid may be supplied to the conduit [130] by operating the hydraulic control apparatus [129] in preparation for subsequent operation.

An embodiment of the invention will now be described in more detail with reference to figure 7, in which conduit [51] provides high pressure fluid from accumulator [9] to the side of auxiliary supply valve [19] of amplification valve [8 ]. A conduit (52) allows high pressure fluid from the accumulator to be introduced into one end of the shut-off valve (38) through a constriction port (54) and a conduit (56) and into the pilot chamber (21) through a constriction port (53) and a conduit (55). One end of the interrupt valve [28] is connected to the guide chamber [21] through a conduit [57] and a conduit [55], and the other end thereof is connected to the low pressure tank [118] through a conduit [58 ]. A conduit (56) connected to one end of the shut-off valve (38) is connected to a gripping mechanism (61) through a conduit (59), and the other end of the shut-off valve (38) is connected to the low-pressure tank (18) through a conduit (60). The gripping mechanism (61) includes a small piston (62) driven by the action of a high-pressure fluid, the small piston (62) pushing a hook (63) rotatable about a shaft (64) fixed to the hydraulic cylinder (5) to maintain engagement between a protruding shaft (50) fixed to the differential piston (3) and the hook (63). It is noted that the shape of the catch [63] is such that when pressure on the small piston [62] is released and an axial (upward) thrust is applied to the differential piston [3], the thrust acting on the differential piston [3] automatically disengages the catch [63] from the protruding shaft [50 ].

Next, the interrupt operation will now be described with reference to the time profile shown in FIG. 9. In the figure, (a) shows an on and off sequence of interrupting an energizing signal of the electromagnetic mechanism [36], (b) shows a change in fluid pressure in a pilot chamber [21] of the auxiliary exhaust valve [19], (c) shows a positional shift of the auxiliary exhaust valve [19] and the auxiliary supply valve [20] moving together, (d) shows a change in fluid pressure in a pilot chamber [15] of the exhaust valve [14], (e) shows a positional shift of the exhaust valve [14] and the supply valve [13] moving together, (f) shows a change in fluid pressure acting on a differential piston large face in a chamber [5b ], (g) shows a movement of the differential piston [3] and (h) shows a movement of the hook [63 ].

FIG. 8 shows the closed state, when the state is changed to a shown in FIG. 9 (a)₁Time point open contact [1]]To the electromagnetic mechanism [36]]When a closing command is issued, the movable iron core [36a ]]Is driven and operated by an operating rod [34]]Acting on the interrupt valve [28]To thereby open the ball valve [30]]。

As a result, the amplification valve [8]]Auxiliary exhaust valve [19]]Guide chamber [21]]Through a conduit [57]]And [58]]Is connected to a low pressure tank [18]]So that the high-pressure liquid is shown in b of FIG. 9 (b)₁The time point is exhausted. Then, c shown in FIG. 9 (c)₁Time point, amplification valve [8]]Auxiliary exhaust valve [19]]Open, assist supply valve [20]]And closing. Therefore, d is shown in FIG. 9 (d)₁Time point, main valve [7]]Exhaust valve [14]]Guide chamber (15)]Through a conduit [22]]Is connected to a low pressure tank [18]]In the guide cavity [15]]The high pressure fluid in the chamber is then evacuated. When in the guide cavity [15]]When the high-pressure fluid therein is exhausted, e is shown in FIG. 9 (e)₁Time point, main valve [7]]Exhaust valve [14]]Is openly connected to the low pressure tank (18)]Conduit (17)]And closing the opposite supply valve [13]]. Then, f is shown in FIG. 9 (f)₁Time point in the cavity [5b ]]Acting internally on differential pistons [3]High pressure fluid on the large piston face through conduit [17]]Is evacuated. As a result, a downward pushing force is generated as shown in the drawing, f is shown in FIG. 9 (f)₁Time point, so that the differential piston [3]]The movement is started in the interrupt direction. When differential piston [3]Complete the movement of the broken direction of the shaft and the convex shaft [50]]Traversing hook [63]]Position (g shown in FIG. 9 (g))₂Time point), h shown in FIG. 9 (h)₁At time point, the hook passes through a spring [88]]Act to begin winding around axis [64]]Rotate and in h₂Time point and protruding axis [50]]And (4) meshing. Hook [63]]Via a spring [86]]Pushing, further withTrigger [84]End portion [84a ] of]And (4) meshing. On the other hand, a in FIG. 9 (a)₂Time point, when sending to the electromagnetic mechanism [36]]When the command is released, the interrupt valve [28] is closed by the hydraulic pressure]Ball valve [30]]And moving upwards for resetting.

At this time, since the high-pressure fluid passes through the conduit [59]]And a constriction [54]]From the accumulator [9]]Supply holding mechanism [61]]Hook [63]]Always by a small piston [62]]Pushed from behind, so that the differential piston [3]]Completes its movement in the interrupted direction (g shown in fig. 9 (g))₁Time point). When the protruding shaft [50]]Traversing hook [63]]At the position of (b), h is shown in FIG. 9 (h)₁Time point, hook [63]]Via a small piston [62]]Push, begin to pivot [64]]Rotated and shown at h in FIG. 9 (h)₂Time point, with convex axis [50]]And (4) meshing. On the other hand, a in FIG. 9 (a)₁Time point, when sending to the electromagnetic mechanism [36]]When the command is released, the ball valve [30]]Under the action of hydraulic pressure, it moves upwards to reset, thus closing the cut-off valve [28]]。

As a result, b in FIG. 9 (b)₂At time point, high pressure fluid passes through the constriction [53]]And a conduit [55]Stepwise application to guide Chamber [21]]When the guide cavity [21]]When the internal pressure reaches a predetermined value, the pressure is applied to the auxiliary valve [20] in a closed state]Above the back pressure applied to the auxiliary exhaust valve [19]]Upper back pressure, so auxiliary blow-off valve [19]]And an auxiliary supply valve [20]]Move together (c shown in fig. 9 (c))₂Time point). Amplifying valve [8]]Auxiliary exhaust valve [19]]Closed to low pressure tank [18]]Conduit [22]]And opens the opposite auxiliary supply valve [20]]. Then, the high-pressure fluid passes through the conduit [51]]And a conduit [16](d is shown in FIG. 9 (d))₂Time point) is applied to the evacuation valve [14]]Guide chamber (15)]Thereby opening and closing the main valve [7]]. When high-pressure fluid acts on the exhaust valve [14]]Guide chamber (15)]In the above, e is shown in FIG. 9 (e)₂Time point, connected to low pressure tank [18]]Conduit (17)]Is closed, so that the opposite supply is closed [13]]And (4) opening. As a result, high-pressure fluid passes through the supply valve [13]]And a conduit [11]To the chamber [5b ]]Differential piston [3]On the large surface of (a), due to the pressure difference of the receiving surface, f shown in FIG. 9 (f)₂At the time point, an upward thrust is generated. However, due to the hook [63]]Has already finished it with the trigger [84]]Is applied to the differential piston [3]]The upward pushing force is provided by a hook (63)]Thus, the interruption operation is completed, and the state shown in fig. 7 is maintained.

The closing operation will now be described. In FIG. 7, when a closing command is given to the electromagnetic mechanism [35] to close the contact [1], the movable iron core [35a ] is driven and acts on the closing valve [38] through the operation rod [33] to open the ball valve [29 ]. This causes conduits [58] and [60] connected to the low pressure reservoir [18] to vent high pressure fluid. As a result, the force for pushing the small piston 62 of the gripping mechanism 61 from behind is released, but when the force of the small piston 62 is released, the hook 63 is shaped, so that the engagement between the hook 63 and the protruding shaft 50 is automatically released by the pushing force of the differential piston 3, and the differential piston 3 starts moving upward, and finally the closing operation is completed. On the other hand, the high-pressure fluid in the accumulator [9] is supplied to the conduit [59] slowly through the conduit [52] and the contraction port [54], thereby forming a state shown in fig. 8 in which the conduit [59] is filled with the high-pressure fluid, and when the operation of the differential piston [3] is completed, the subsequent interrupting operation is ready to be performed.

Due to the arrangement of the mechanism of the invention, the end faces of the conduit and the differential piston are kept at a high pressure unless in the operating state, for which reason air mixed or dissolved in the fluid does not form bubbles and thus a constant switching time is established. Therefore, the operation is not required to be repeated after the mechanism is assembled so as to remove air mixed in the fluid, and the method has the advantage of convenient operation of the substation.

Furthermore, since high-pressure fluid is almost always applied to the end face and rod side of the differential piston, it is not necessary to take a strict fluid sealing measure between the differential piston [3] and the hydraulic cylinder [5] and there is no sudden pressure decrease due to leakage of the high-pressure fluid to the low-pressure tank [18 ].

In the description of one embodiment of the present invention, the terms "close" and "interrupt" are replaced with the terms "interrupt" and "close", respectively, to achieve the same effect.

Although the description has been made in the case of the present application in which the main valve and the amplification valve are used together to supply and discharge the high-pressure fluid associated with the large area side of the differential piston, the above-described amplification valve may be used to directly supply and discharge the high-pressure fluid associated with the large area side of the differential piston, and in such a case, the same advantageous effects can be obtained.

As already stated, the hydraulic operating mechanism according to the invention is thus arranged. The hydraulic pressure on the large piston face side of the end face is always high unless in the state of issuing an operation command, and when the piston is stopped at its retracted position, the thrust generated by the difference in force exerted on both faces of the piston is caught by the holding mechanism, so that any gas dissolved in the fluid does not form bubbles that make the switching time inconstant, and therefore, after the mechanism is assembled, it is not necessary to repeat the operation to remove air mixed in the fluid.

The hydraulic operating mechanism of the present invention is arranged so that the hydraulic pressure applied to the large piston face side of the end face and the hydraulic pressure applied to the side of the main valve for corresponding selective change are always high unless in the state of issuing an operating command, and when the piston is stopped at its retracted position, the piston thrust generated by the difference in force applied to both the end face and the rod side of the piston is caught by the holding mechanism, so that any gas dissolved and mixed in the fluid does not form bubbles that change the switching time.

Since the general liquid operating mechanism structure has been described, when a short pulse operation command is issued to the interrupting solenoid mechanism [36], the ball valve [30] is opened only for a moment to reduce the pressure in the pilot chamber [21] only for a moment, so that the amplifying valve [8] is in the opposite state. However, since the operation command is continued for only a short time, the ball valve is immediately reset, and the high-pressure fluid is supplied again from the contraction port [53] to the pilot chamber [21], so that the amplification valve [8] is immediately returned to the state before the operation command is issued. Since the main valve [7] is returned to its original state from the opposite position according to the operation command, the differential piston [3] which is finally moved to the interrupting direction is returned to the closing direction and moved upward before the completion of the movement.

Since the hydraulic operating mechanism of the present invention is so designed, the high-pressure fluid for returning the hydraulic switching valve is supplied through those portions which perform the switching action in response to the differential piston once the interrupting operation is completed.

Therefore, once the operation of the differential piston is found to be completed, the hydraulic switching valve is supplied with high-pressure fluid, and the hydraulic operating mechanism can be operated appropriately even when an operation command is issued in the form of a short pulse to the interrupting solenoid mechanism.

Another embodiment of the present invention will now be described with reference to the accompanying drawings. In fig. 10, 74 is a damping ring configured to allow it to slide slightly vertically along the inner wall of the cylinder 5. In this state, the piston [3] is pushed toward the cushion ring [74], a guide pipe [76] provided in the cylinder [5] is led to the guide pipe [77] around an annular groove [73] provided around the cushion ring [74], and the annular groove [73] is separated from the piston large-face side chamber [5b ] in an oil-tight manner. Further, when the cushion ring [74] is not compressed by the piston [3] and the fluid pressure inside the conduits [76] and [77] is higher than the hydraulic pressure in the piston large face side chamber [5b ], the cushion ring [74] is pushed upward, so that the piston large face side chamber [5b ] and the conduits [76], [77] are communicated. A conduit (76) is connected to the conduit (11), the conduit (11) is always at high pressure, and high pressure fluid flows from the accumulator (9) to the low pressure tank (18) through a constriction (75) regulating discharge, and the conduit (77) is connected to the pilot chamber (21) through a constriction (72) and a conduit (71).

The interruption operation of the mechanism according to the invention will be described below with reference to the time curve shown in fig. 12. In the figure, (a) shows an on-off state of interrupting an excitation signal of the electromagnetic mechanism [36], (b) shows a change in hydraulic pressure in a pilot chamber [21] of the auxiliary exhaust valve [19], (c) shows a position of the auxiliary exhaust valve [19] and the auxiliary supply valve [20] moving together, (d) shows a change in hydraulic pressure in a pilot chamber [15] of the exhaust valve [14], (c) shows a position of the exhaust valve [14] and the supply valve [13] moving together, (f) shows a change in hydraulic pressure on the large piston side of the differential piston end face in the chamber [5b ], (g) shows a displacement of the differential piston [3], (h) shows a displacement of the hook [63], and (i) shows a change in hydraulic pressure in the ring groove [73 ].

FIG. 10 shows a closed state, which is a state shown in FIG. 12 (a)₁Time point when the contact [1] is opened]To electromagnetic mechanism [36]]When a closing command is issued, the movable iron core [86a ]]Is driven and operated by an operating rod [34]]Acting on the interrupt valve [28]To open the ball valve [30]]. As a result, the amplification valve [8]]Auxiliary exhaust valve [19]]Guide chamber [21]]Through a conduit [57]]And [58]]Is connected to a low pressure tank [18]]Therefore, b is shown in FIG. 12 (b)₁At time point, the high pressure fluid is evacuated. For this purpose, c is shown in FIG. 12 (c)₁Time point, amplification valve [8]]Auxiliary exhaust valve [19]]Open to assist the supply valve [20]]It is turned off. Thus, the main valve [7]]Exhaust valve [14]]Guide chamber (15)]Through a conduit [16]]And a conduit [22]]To a low pressure tank [18]]D is shown in FIG. 12 (d)₁Time point, guide lumen [15]]The high pressure fluid in the chamber is evacuated. When the guide cavity [15]]When the high-pressure fluid therein is exhausted, e is shown in fig. 12 (e)₁Time point, main valve [7]]Exhaust valve [14]]Is openly connected to the low pressure tank (18)]Conduit (17)]And closing the opposite supply valve [13]]. Then, f is shown in FIG. 12 (f)₁Time point in the cavity [5b ]]Internal differential piston [3]The high-pressure fluid on the large surface side of the piston passes through a conduit [17]]Is evacuated. As a result, a downward thrust is generated as shown in the drawing, and f is shown in FIG. 12 (f)₁Time point, so that the differential piston [3]]Starting to move in the interrupt direction. When differential piston [3]Completing the movement in the direction of interruption and the protruding axis [50]]Traversing hook [63]]Position (g shown in FIG. 12 (g))₂Time point), h shown in FIG. 12 (h)₁At time point, the hook passes through a spring [88]]Push, begin to pivot [64]]Rotate at h₂Time point, hook and protruding shaft [50]]And (4) meshing. In addition, the hook [63]]Via a spring [86]]Push, with trigger [84]]End portion [84a ] of]And (4) meshing. On the other hand, a in FIG. 12 (a)₂Time point, when to electromagnetic mechanism [36]]When the command is released, the ball valve [30] is operated by hydraulic pressure]Moves upward, closing the interrupt valve [28]]。

When the cavity [5b ]]Internal differential piston [3]When the pressure on the large face side is reduced, the conduit [76]And [77]]The high pressure fluid in the buffer ring [74] is driven at the same time as the high pressure fluid in the buffer ring is exhausted]From the constriction [75]]The slowly supplied high-pressure fluid is also simultaneously evacuated (see i shown in fig. 12)₂Time point).

Therefore, even if the operation command is supplied in the form of a pulse, once the amplification valve [8] and the main valve [7] change their states, as described above, the high-pressure fluid in the conduit [77] is evacuated, so even if the interrupt valve [28] is closed after the operation command is released, the amplification valve [8] and the main valve [7] do not change and return their original states until the differential piston [3] completes its operation.

In this state, the interrupt action is complete, buffering the ring [74]]Lower surface and hydraulic cylinder [5]]Are in close contact. Therefore, i shown in FIG. 12 (i)₂At the point of time, from the accumulator [9]]Through a constriction [75]]Supply to the ring groove [73]]B in FIG. 12 (b)₂At this point, the high pressure fluid further passes through the constriction [72]]And a conduit [71]Slowly supplied to the guide chamber [21]]. When the guide cavity [21]]When the internal pressure reaches a predetermined value, the internal pressure is applied to the auxiliary supply valve [20]]Above the back pressure applied to the auxiliary exhaust valve [19]]On back pressure, thereby moving the auxiliary exhaust valve [19] together]And an auxiliary supply valve [20]](see c in FIG. 12 (c)₂Time point). Amplifying valve [8]]Auxiliary space discharge valve [19]]Close and connect the low pressure tank (18)]Conduit [22]]And opening and opposing conduit [22]]An associated auxiliary supply valve. D in FIG. 12 (d)₂At a point in time which causes high pressure fluid to pass through the conduit [12]]，[51]And [16]]To an exhaust valve [14]]Guide chamber (15)]Thereby switching on and off the main valve again [7]]. When high-pressure liquid acts on the guide cavity (15)]In the above, e is shown in FIG. 12 (e)₂Time point, evacuation valve [14]]Shut off connection to low pressure tank [18]Conduit (17)]And opening a conduit [17] provided in the conduit]Opposite sideSupply valve [13]]. As a result, f is shown in FIG. 12 (f)₂At the point in time, high pressure fluid passes through supply valve [13]]And a conduit [11]To a differential piston [3]]Large side cavity [5b ]]Due to differential piston [3]]Receiving the pressure difference on the surface, an upward thrust is generated. However, due to the hook [63]]And a protruding shaft [50]]The engagement therebetween has been completed (see h shown in fig. 12 (h))₂Time point) and due to back pressure (by passage through constrictions [54]]And a conduit [59]]Caused by the supply of high pressure fluid) is applied to the small piston, so that an upward pushing force is exerted by the catch [63]]The operation is interrupted by gripping, and the state shown in fig. 10 is maintained.

Since the closing operation is the same as the mechanism previously described in connection with fig. 7 to 9, the description thereof will be omitted.

Another embodiment of the present invention will be described below. Fig. 13 is a sectional view showing a main part of the present embodiment of the present invention. In this figure, 102 is a seal for fluidly sealing the sliding gap between the piston 5 and the cushion ring 74.

In the final state of the interrupted operation, when the differential piston [3] starts to engage with the cushion ring [74], the pressure in the space defined by the differential piston [3] and the cushion ring [74] increases, and the fluid pressure generates a control force. At this point, if there is no seal [102], the high pressure fluid will enter the conduit [77] through the gap [101 ].

Thus, when the braking force generated by the damping ring [74] is very large, since the space [103] is under very high pressure and the pressure within the conduit [77] is varying, high pressure fluid is forced into the conduit [77], thereby causing a change in pressure within the guide chamber [21] through the constriction [72 ]. Therefore, at a time point earlier than the start state, a malfunction in which the auxiliary exhaust valve [19] is driven may occur.

In this case, as shown in fig. 13, a seal [102] may be provided between the hydraulic cylinder [5] and the cushion ring [74] to prevent the high-pressure fluid from passing through the cushion ring [74] from the working area, so that the fear of erroneous operation can be eliminated.

Another embodiment having the same purpose as the embodiment described in connection with fig. 13 will now be described.

In FIG. 14, [77a ] is a conduit connecting the contraction port [75] and the contraction port [72], and [77a ] is always supplied with high-pressure fluid from the accumulator [9] through the contraction port [75 ]. The middle portion of the conduit [77a ] is a branch into the conduit [110 ]. The end of the conduit [110] opposite the conduit [77a ] forms an opening [110a ] which is closed when the damping ring [74a ] is pushed down to the bottom position by the differential piston [3 ]. If the cushion ring [74b ] is not completely pushed down by the differential piston [3], the pressure in the conduits [77a ] and [110] becomes high, the cushion ring [74b ] is pushed up by the fluid pressure, and the opening [110a ] of the conduit [110] is opened. Therefore, in the initial state of the interrupting operation, the high-pressure fluid in the conduit [77a ] is discharged through the opening [110a ], thereby preventing the high-pressure fluid from being sent into the conduit [71] and the guide chamber [21 ].

On the other hand, in the final state of the interrupting operation, the opening [110a ] is closed by the cushion ring [74a ], so that the high-pressure fluid supplied through the constriction port [75] in the conduit [77a ] is maintained, and the high-pressure fluid is sent into the conduit [71] and the guide chamber [21 ]. At this time, the high-pressure fluid in the space [103] between the differential piston [3] and the cushion ring [74b ] enters the gap [101], but the opening [110a ] is blocked by the cushion ring [74b ], so that the high-pressure fluid cannot enter the inside of the conduit [77a ].

As has been described, since the lines are arranged in this way, according to the present invention, after the interrupting operation is completed, high-pressure fluid is supplied to the hydraulic switching valve, and the hydraulic operating mechanism is normally operated even when a pulse type operation command is supplied to the interrupting electromagnetic mechanism.

In addition to this, the operating mechanism for the interrupter must have a so-called "anti-jump function". For example, when an interruption command is issued to eliminate an abnormal condition of the power system and at the same time, a closing command is manually issued to the interrupter, the simultaneous activation prevention function (usually executed by an electric line) can be activated to complete the interruption operation after the closing operation is completed. At this time, if the closing command is still present after the completion of the interrupting operation, the interrupter is re-closed, so that the abnormal situation in the power system may continue to exist. This phenomenon is called a jump operation and should be prevented by electrical or mechanical measures.

The jumping operation will be described with reference to fig. 15, in which an interruption command and a closing command are issued to the terminals T and C, respectively, and the interrupter is operated by energizing the interruption coil TT or the closing coil CC. The contacts Aa and Ab are auxiliary contacts cooperating with the interrupter, and in the interrupting state of the interrupter, the contact Aa is opened and the contact Ab is closed. In the closed state, contact Aa is closed and contact Ab is open. Coil Y is an anti-bounce electromagnetic relay. When the coil Y is energized, the contact Ya is closed and the contact Yb is opened.

In the interruption state, for example, when a closing command is issued to the connector C, the closing coil CC is energized by the contacts Yb and Ya, causing the interrupter to close. When contact closure has been completed, contact Aa is closed and contact Ab is opened to deactivate the closure coil. At this point, if the closing command continues to be maintained, the current reaches self-locking through the coil Y by means of the closing contact Ya, while the contact Yb is opened. When an interrupt command is given to the terminal T in this case, the interrupt coil TT is energized via the contact Aa to thereby interrupt the interrupter, and the contact Aa is reopened to close the contact Ab. Even in this state, if the closing command is still present, the interrupter is reclosed and a bouncing operation occurs unless the contacts Yb are coupled in series with the closing coil CC, but since the contacts Yb of the latching coil Y are connected, no bouncing operation occurs in the line shown in fig. 15.

Since a typical hydraulic operating mechanism is arranged as described above, the anti-bounce function is usually provided by an electromagnetic relay having a complicated control circuit. For this reason, malfunction may occur due to oscillation caused by the interruption itself, and the mechanism becomes excessively bulky and expensive due to the increase in the number of electromagnetic relays.

The hydraulic operating mechanism of the present invention utilizes a mechanism amplifying mechanism for amplifying an operating signal in order to allow the holding mechanism to hold the thrust force acting on the differential piston, so that the anti-jump function mechanism of the hydraulic operating mechanism can be made into a mechanical device, and for this reason, the anti-jump function mechanism can be made very simple and inexpensive.

The closing electromagnetic mechanism [135] shown in fig. 16-21 includes a stationary coil [135b ] mounted at a stationary end [80] and a movable iron core [135a ]. An anti-bouncing link [81] is pivotally mounted on one end of the movable iron core [135a ] by a pivot [82 ]. One side of the anti-bounce linkage [81] is biased by a spring [83] to form a notch [81a ] where one end [84c ] of a trigger [84] that pivots on a pivot [85] engages. The trigger [84] is biased by a spring [86 ]. A stopper (87) is provided for determining the stop position of the trigger (84). The trigger [84] has a projection [84b ]. The holding mechanism [87] is used to determine the stop position of the trigger [84 ]. An anti-bounce pivot [89] is mounted in a position relative to the anti-bounce linkage [81] and is urged from the back by a spring [90 ]. In the interrupting state of the interrupter. One end [84a ] of a trigger [84] opposite to the anti-bounce link [81] supports the hook [63] from the back of the hook [63] to mechanically grasp the engagement of the boss shaft [50] and the hook [63 ]. The catch [63] is urged from its rear by a spring [88] having a spring force selected so that when the engagement between the trigger [84] and the catch [63] is released, the engagement between the catch [63] and the protruding shaft [50] is automatically released.

Next, the closing operation of the above mechanism of the present invention will now be described.

Fig. 18 shows an interruption state in which the movable iron core [135a ] is driven to move the anti-bounce link [81] downward when a close command is given to the electromagnetic mechanism [135] in order to close the contact 1. Thus, one end [84c ] of the trigger [84] urges the trigger to rotate clockwise, and the engagement between the end [84a ] of the trigger [84] and the hook [63] is released. At this time, high-pressure fluid is supplied to both piston surfaces [5a ] and [5b ] of the differential piston [3], and the thrust of the differential piston [3] generated by the difference in piston area of the differential piston causes the engagement between the hook [63] and the protruding shaft [50] to be released, thereby moving the differential piston [3] upward, thereby closing the interrupter. At this time, as the trigger [84] rotates, the projection [84b ] causes the anti-bounce link [81] to rotate, at which moment the closing command is released, and the trigger [84] and the anti-bounce link [81] take the positions shown in fig. 16 and 17 to complete the closing operation.

The interrupt operation will now be described. In fig. 16 and 17, a closed state is shown, and when a closing command is given to the electromagnetic mechanism [36] to open the contacts, the movable iron core [36a ] is driven to act on the interrupting valve [28] through the operating lever [34] to open the ball valve [30 ]. In the same manner as in the conventional mechanism, the amplification valve [8] and the main valve [7] are opened and closed, and high-pressure fluid on the large piston face of the differential piston [3] is exhausted in the chamber [5b ], so that the differential piston [3] moves downward, and when the projected shaft [50] moves across the hook [63] biased by the spring [88], the hook [63] engages with the projected shaft [50], and the end [84a ] of the trigger [84] biased by the spring [86] engages with the hook [63 ]. Thereafter, the amplification valve [8] and the main valve [7] identical to the one-stage mechanism are reset, so that high-pressure fluid is applied to the large piston face of the chamber [5b ], thus completing the interruption state shown in fig. 18 and 19.

The anti-bounce function will now be described. Even after the completion of the contact closing, that is, the closed state shown in fig. 16 and 17, when the closing command is continued, the anti-jump link [81] engages with the anti-jump pivot [89], as shown in fig. 20, to prevent the anti-jump link [81] from being restored. In this state, when the interrupt command is issued and the differential piston [3] moves downward to engage the boss shaft and the hook [63], the trigger [84] is reset to grasp the engagement of the boss shaft [50] and the hook [63 ]. However, since the anti-bounce link [81] is prevented from being reset by the anti-bounce pivot [89], unless the closing command is released and the notch [81a ] and end [84c ] of the trigger [81] are engaged, as shown in fig. 18 and 19, the interrupter is no longer closed, so the anti-bounce function is achieved.

As has been described, the hydraulic operating mechanism of the present invention is arranged such that the amplification of the operating signal of the gripping mechanism for gripping the pushing force acting on the differential piston is performed by a mechanical amplification device having a trigger instead of a hydraulic switching valve, and thus the anti-bounce function can be obtained with a very simple mechanism as compared with a general mechanism using an electromagnetic relay. Therefore, the hydraulic operating mechanism with reliable performance and low-cost anti-jump function can be obtained.

Although the invention has been described in relation to several practical embodiments of the invention, it is also possible to combine the third embodiment shown in fig. 10-14 with the fourth embodiment shown in fig. 17-22 to obtain the fifth embodiment illustrated in fig. 22 and 23.

Claims (9)

1. A hydraulic operating mechanism in which a differential piston is used as the drive member, wherein the differential piston is driven by a high-pressure fluid applied to a large piston face through a hydraulic control mechanism for controlling hydraulic pressure, At the same time, the differential piston is also driven by high pressure fluid constantly applied to the small piston face. The structure of the liquid operating mechanism is arranged in such a way that when the differential piston stops at its return position, the high pressure fluid acts simultaneously On the two piston surfaces, the thrust generated by the force difference applied to the two piston surfaces is held by the holding mechanism acting on the differential piston or its extension, the Once the grip force of the grip mechanism is released, the differential piston moves forward, and once the high pressure fluid applied to the large piston face side is released, the piston moves in the opposite direction. 2. The hydraulic operating mechanism according to claim 1, wherein both the amplification of the operating signal of the holding mechanism and the amplification of the input signal for operating the hydraulic switching valve are performed by hydraulic pressure, which is the reply The high-pressure fluid of the hydraulic switching valve is provided by a pressure accumulator that always maintains high pressure through the constriction port. 3. The hydraulic operating mechanism according to claim 1, wherein both the amplification of the operating signal of the holding mechanism and the amplification of the input signal for operating the hydraulic switching valve are performed by hydraulic pressure, which is the reply The high-pressure fluid of the hydraulic switch valve is supplied by a pressure release function part that switches according to the movement of the differential piston, and the pressure release function part is provided between a pressure accumulator that always maintains high pressure and the hydraulic switch valve. between. 4. The hydraulic operating mechanism as claimed in claim 1, wherein said pressure release function part comprises a ring body coaxially engaged with said differential piston, and said ring body can follow the inner wall of said differential pressure slide. 5. The hydraulic operating mechanism according to claim 1, wherein a constriction element is interposed between the pressure relief function and the pressure accumulator. 6. The hydraulic operating mechanism as claimed in claim 1, wherein the amplification of the operating signal of the holding mechanism is realized mechanically, and the amplification of the input signal for operating the hydraulic switch valve is performed hydraulically , the high-pressure fluid returning to the hydraulic switching valve is provided by a pressure release function part that switches according to the movement of the differential piston, and the pressure release function part is placed between the pressure accumulator that always maintains high pressure and the hydraulic pressure between switch valves. 7. The hydraulic operating mechanism as set forth in claim 6, wherein said pressure relief portion comprises a ring body coaxially engaged with said differential piston, and said ring body is movable along the inner wall of said differential hydraulic cylinder. slide. 8. The hydraulic operating mechanism of claim 6, wherein a constriction element is interposed between the pressure relief function and the pressure accumulator. 9. The hydraulic operating mechanism according to claim 1, wherein the amplification of the operating signal of the holding mechanism is realized mechanically, and the amplification of the input signal for operating the hydraulic switch valve is realized hydraulically , the high-pressure fluid returning to the hydraulic switch valve is provided by the pressure accumulator that always maintains high pressure through the constriction port.

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