JPH09303467A - Shock absorber for switch operation mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the limitation of the fitting attitude by setting a gap between a buffer piston and the inner periphery of an oil chamber larger than the gap between the inner peripheries of the first and second buffer orifices and the first and second action end sections, and filling oil in the gap and an oil feedback passage. SOLUTION: The first and second buffer orifices 103, 104 opened to an oil chamber 102 are provided on end section walls 101a, 101b at both ends of a shock absorber main body 101 respectively. The gap D between a buffer piston 112 and the inner periphery of the oil chamber 102 is set sufficiently larger than the gap (d) between the inner peripheries of the first and second buffer orifices 103, 104 and the first and second action end sections 112b, 112c of the buffer piston 112, and an oil liquid is filled in the gap D and the first and second feedback passages 132, 133. The fitting attitude is not limited, and a shock buffer can be miniaturized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorber used as an operating mechanism for operating a switch such as a circuit breaker or a disconnector.

[0002]

2. Description of the Related Art Various types of operating mechanisms are used for operating switches such as circuit breakers and disconnecting switches. Since a large impact occurs, it is necessary to provide a shock absorber to absorb the impact.

FIG. 4 shows a conventional shock absorber 100 '.
This example shows a shock absorber body 101 ′ having a cylinder 101 A ′ whose axis extends horizontally and an air chamber 101 B ′ arranged above the cylinder 101 A ′, and a shock absorber main body 101 ′. End wall 10 of the container body 101 '
1a 'is provided with a slide rod 111' slidably supported via a bearing having a liquid-tight structure, and a piston 112 'fitted in the cylinder 101A' and fixed to the end of the rod 111 '. An oil chamber is formed inside the cylinder 101A '. In the lower part of the cylinder 101A ', a large number of orifices 101h', 101h ', ... Are provided in a line in the axial direction of the cylinder. These orifices communicate with the inside of the air chamber 101B 'through a gap formed outside the cylinder 101A'. Inside the cylinder 101A 'and the cylinder 101A'
A buffering oil 135 'is stored in the gap outside the. The slide rod 111 'is connected to the buffered rod in the operating mechanism and is displaced together with the buffered rod. Here, the buffered rod is a rod to which a large impact is applied when the rod is rapidly moved and stopped during the operation of the switch, and for example, the operating force at the time of interruption is obtained by the urging force of the interruption spring. The spring operating device is a rod or the like that is biased by a blocking spring.

In the above shock absorber, the slide rod 111 'is rapidly moved to the left in the drawing when the operating mechanism is operated. When the rod 111 'moves, the oil 13 in the cylinder 101A' moves as the piston 112 'moves.
5'is compressed so that the oil 135 'moves from the piston 112
A reaction force acts on the rod ′ and the rod 111 ′. This reaction force is
Orifice 10 provided at the bottom of cylinder 101A '
It is adjusted by ejecting compressed oil from 1 h '. In the air chamber 101B ', the rod 111' has the cylinder 1
It is provided to absorb a change in the volume of oil caused by going in and out of 01A '. The above buffer 10
0'needs to be attached with the air chamber 101B 'positioned above.

In the example shown in FIG. 4, the slide rod 11
1'is provided so as to extend in the horizontal direction, but depending on the configuration of the operating mechanism, it may be necessary to provide the slide rod 111 'in the vertical direction. In that case, it is necessary to change the internal structure so that the air chamber is located above the oil chamber.

[0006]

The conventional shock absorber has the following problems.

(A) Since it is necessary to provide the air chamber above the oil chamber in order to absorb the volume change of the buffer oil caused by the movement of the shaft, the mounting posture thereof is limited.

(B) Since it is necessary to provide an air chamber inside the shock absorber body, the shock absorber as a whole becomes large.

(C) Since the shock absorber becomes large in size, it is difficult to incorporate the shock absorber into the operating mechanism.

(D) Since it is necessary to change the internal structure according to the direction of the shock-absorbed shaft, standardization of the constituent parts of the shock absorber cannot be achieved, and the cost of the shock absorber is inevitably increased. .

An object of the present invention is to provide a switch operating mechanism shock absorber which is not restricted in its mounting posture.

Another object of the present invention is to provide a switch operating mechanism shock absorber which can be made smaller than the conventional one.

Still another object of the present invention is to provide a shock absorber for a switch operating mechanism which has the same internal structure and can be standardized regardless of the orientation of the shock-absorbed shaft. is there.

[0014]

SUMMARY OF THE INVENTION The present invention relates to a shock absorber attached to an operating mechanism for operating a switch such as a circuit breaker or a disconnector.

In the shock absorber according to the present invention, an oil chamber is formed inside the shock absorber main body, and first and second end walls provided at one end and the other end of the oil chamber in the axial direction, respectively. First and second buffer orifices are formed in the oil chamber. Further, a slide rod that penetrates the first and second end walls of the shock absorber body and extends in the axial direction of the oil chamber is provided, and the slide rod is slidably supported with respect to the shock absorber body. A cushioning piston that moves with the slide rod inside the main body is fixed to the slide rod. The cushioning piston used in the present invention has a first end portion and a second end portion each having a first end.
First and second cushioning end portions having a shape capable of being fitted in the second cushioning orifice and the second cushioning orifice, and the cushioning piston includes the first end wall side and the second cushioning end. The first and second cushioning end portions of the cushioning piston are adapted to fit into the first and second cushioning orifices, respectively, when they move to the end wall side of the cushioning piston. Further, an oil return passage for returning the oil flowing out from the first and second buffer orifices to the oil chamber is provided.

According to the present invention, the first working end and the second working end of the cushioning piston are respectively fitted into the first and second cushioning orifices, respectively. The gap formed between the buffer piston and the inner periphery of the oil chamber is larger than the gap formed between the inner peripheral surface of the buffer orifice and the first and second working ends, respectively. , The inner diameter of the oil chamber and the inner diameter of the first and second buffer orifices are set, and when the first and second working ends enter the first and second buffer orifices, respectively, the slide rod Make sure that a large reaction force acts on.

Further, in the present invention, oil is filled in the oil chamber, the first and second buffer orifices, and the oil return passage without providing the air chamber in the buffer body.

With the above construction, when the slide rod moves in either direction in accordance with the operation of the operating mechanism, the buffer piston moves in the same direction as the slide rod, and the buffer piston is provided with the first rod. The one buffering end or the second buffering end moves to the first buffering orifice side or the second buffering orifice side. In the state before the buffering end enters the buffering orifice, the buffering piston moves in the oil chamber with relatively little resistance, but when any buffering end enters the buffering orifice, the buffering orifice starts from that moment. The internal pressure rises, and a large reaction force that pushes back the buffer piston is generated. This reaction force reduces the impact on the operating mechanism. The oil in the buffer orifice whose pressure has risen due to the entrance of the buffer action end is returned to the oil chamber through the oil return passage.

As described above, when the slide rod is provided with the shock absorber main body penetrating therethrough, the volume of the oil in the shock absorber main body does not change with the movement of the slide rod, so that the shock absorber is buffered. There is no need to provide an air chamber for absorbing the volume change of oil in the main body of the container. Therefore, the shock absorber main body can be configured in a small size, and the shock absorber can be downsized. By making the shock absorber small, it becomes possible to incorporate the shock absorber into the inside of the cutoff spring of the operating mechanism, and the operating mechanism can be made compact.

Further, with the above construction, since the air chamber is not provided in the shock absorber main body, the same shock absorber can be attached in either the horizontal direction or the vertical direction, and the direction of the shaft for cushioning can be changed. The same shock absorber can be applied to different operating mechanisms. Therefore, the cost of the shock absorber can be reduced by standardizing the components of the shock absorber.

The first and second buffering orifices are formed in such a shape that their inner diameters gradually increase toward the first and second buffering end portions of the buffering piston, respectively. It is preferable that the cushioning end portions are formed in a shape in which the diameter gradually decreases toward the first and second cushioning orifices, respectively.

In the present invention, it is also preferable to provide an adjustable throttle valve in the middle of the oil return passage.

When the throttle valve is provided as described above, the flow rate of the oil returned through the oil return passage can be adjusted by adjusting the throttle valve, so that the reaction force that contributes to the buffering action can be adjusted. Therefore, the buffering effect can be adjusted appropriately.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows a shock absorber 10 according to the present invention.
0 is an example of the configuration, in which 101 is the first
And a shock absorber body having second end walls 101a and 101b and a cylindrical peripheral wall portion 101c. An oil chamber 102 is formed inside the peripheral wall portion 101c of the shock absorber body,
First and second buffer orifices 103 and 104 opening into the oil chamber 102 are formed in the central portions of the first and second end walls 101a and 101b, respectively.

At the center of the first and second end walls 101a and 101b of the shock absorber body 101, first and second recesses 105 and 106 that open to the outside are also formed. The first and second buffer orifices 103 and 104 are divided into the first partition wall and the first partition wall by penetrating the partition walls.
And second through holes 107 and 108 are provided.
First and second bearing members 109 and 11 formed annularly in the first and second recesses 105 and 106, respectively.
0 is attached respectively. These bearing members are attached by screwing threaded portions 109a and 110a provided on the outer circumferences of the bearings into threaded portions provided on the inner circumferences of the recesses 105 and 106, respectively.

Bearing members 109 and 110 and through hole 107
And 108 are provided to extend through the oil chamber 102 along the central axis thereof, and a slide piston 111 fixed to the slide rod 111 that moves together with the slide rod in the shock absorber body is fixed to the slide rod 111. Has been done.

In order to seal the penetrating portion of the slide rod 111, O-rings 113 are fitted in grooves provided on the inner and outer circumferences of the end portion of the bearing member 109 near the through hole 107, respectively. Similarly, the through hole 108 of the bearing member 110.
Grooves are provided on the inner and outer peripheries of the end portions closer to each other, and the O-ring 113 is fitted in each groove. Further, in the illustrated example, recesses that are open to the slide rod side and the outside in the axial direction are provided in the inner peripheral portions of the bearing members 109 and 110, and the slide rods 111 are brought into contact with the recesses to absorb dust. A dust seal 114 is held to prevent the dust seal 114 from entering the container body.

The buffer piston 112 has a cylindrical piston main body 112a formed so as to share a central axis with a cylindrical peripheral wall portion 101c surrounding the oil chamber 102, and one end side and the other end in the axial direction of the piston main body. First and second cushioning ends 112b and 1 formed on the sides, respectively.
It consists of 12c. The first and second cushioning end portions 112b and 112c are respectively the piston body 112a.
Are provided so as to project from the end surface on one end side and the end surface on the other end side toward the first buffer orifice 103 side and the second buffer orifice 104 side, and gradually toward the first and second buffer orifice sides. A shape in which the outer peripheral surface is tapered so that the outer diameter becomes smaller (in the example shown, a truncated cone shape)
Is formed. First and second cushioning end 112
The outer diameters of the maximum diameter portions (end portions on the piston body side) of b and 112c are set to be smaller than the outer diameter of the piston body 112a, and the outer circumferences of one end and the other end of the piston body 112a in the axial direction are close to Part (first and second
(A portion located further outside in the radial direction than the outer peripheral portion of the cushioning action end portion) is provided with first and second action end surfaces 112d and 112e made of a flat surface extending in a direction orthogonal to the axis of the slide rod. .

The first and second buffer orifices 103 are also provided.
Each of the buffer pistons 104 and 104 is formed in a shape (mortar shape) in which the inner peripheral surface is tapered so that the inner diameter gradually increases toward the buffer piston side.
Move toward the first end wall 101a side and the second end wall 101b side, respectively, the first working end 112b and the second working end 112c of the cushioning piston move to the first working end 112c and the second working end 112c respectively. Inner diameters and taper angles of the inner peripheral surfaces of the first and second cushioning orifices and the first and second cushioning end portions of the cushioning piston so that they can be fitted into the cushioning orifices 103 and 104 of The outer diameter dimension and the taper angle of the outer peripheral surface are set.

In the illustrated example, the inclination angles of the outer circumferences of the first and second cushioning end portions 112b and 112c of the cushioning piston and the inclination angles of the inner periphery of the first and second cushioning orifices 103 and 104 are defined by Equally set so that the first and second cushioning ends 112b and 112c are respectively the first and second
Of the first and second buffering orifices and the first and second buffering end portions when fitted in the buffering orifices 103 and 104 of FIG. Has become. In addition, a cylindrical peripheral wall portion 101 surrounding the outer peripheral surface of the piston body 112 a and the oil chamber 102.
The gap D between the inner peripheral surface of c is smaller than the gap d formed between the first and second cushioning orifices 103 and 104 and the first and second cushioning end portions 112b and 112c, respectively. It is set large enough.

In the illustrated example, the buffering ends 112b and 112c at both ends of the buffering piston 112 are formed in a completely symmetrical shape, and the first and second buffering orifices 103 and 103 respectively receiving the buffering ends are formed. 104 is also formed in a completely symmetrical shape. The first and second
The gaps d formed between the cushioning orifice and the first and second cushioning ends are set to be equal.

Inside the first and second end walls 101a and 101b of the shock absorber main body 101, the guide rod 111 of the guide rod 111 is positioned in the vicinity of the deepest part of the first and second shock absorbing orifices 103 and 104. Conical holes 120 and 121 extending in a direction orthogonal to the axis are formed, respectively. One end of each of the conical holes 120 and 121 opens into the first and second buffer orifices 103 and 104, and the other end opens into the outer periphery of the first and second end walls. Further, the central portion in the axial direction of the peripheral wall portion 101c of the shock absorber body 101 and the first and second end wall portions 101a and 101
The portion between b and the conical hole 12
2 and 123 are provided. Further, conical holes 124 and 125 orthogonal to the conical holes 120 and 121 are provided inside the first and second end walls 101a and 101b and the peripheral wall part 101c. The conical holes 124 and 125 are
One end of each of the first and second end walls 101a and 101a
01b is opened at the outer end surface and the other ends are conical holes 122 and 123.
It is provided so as to open inside. Buffer body 101
The openings of the conical holes 122 and 123 located on the outer peripheral side of the are closed oil-tightly by the plugs 126 and 127, respectively.
And the openings of the conical holes 124 and 125 opened on the outer end surfaces of the second end walls 101a and 101b are plugs 128, respectively.
And 129 are oil-tightly closed. Further, the first and second throttle valves 130 and 131 are inserted into both the cone holes 120 and 121 from the openings of the cone holes 120 and 121 located on the outer peripheral side of the shock absorber body 101, and by these throttle valves, From the first buffer orifice 103 to the conical holes 120, 1
Of the oil flowing in the flow path to the oil chamber 101c through the hole 24 and the conical hole 122, and the amount of oil flowing in the flow path from the second buffer orifice 104 to the oil chamber 101c through the conical holes 121 and 125 and the conical hole 123. The flow rate is adjusted.

In the above example, the conical holes 120, 122 and 1
The first oil return passage 13 for returning the oil flowing out through the first orifice 103 to the inside of the oil chamber 101c by 24
2 is formed, and by the conical holes 121, 123, and 125,
The oil flowing out through the second orifice 104 is transferred to the oil chamber 10
A second oil return passage 133 for returning the oil to the inside of 1c is formed. In the entire space in the shock absorber body, that is, in the oil chamber 102, the first and second buffer orifices 103 and 104, and the first and second oil return passages 132 and 133,
A buffering oil 135 is filled.

The illustrated first and second throttle valves 130 and 1
Reference numeral 31 denotes an adjusting portion 130a provided at each outer end portion.
And 131a are rotated to move the valve bodies 130b and 131b into and out of the conical holes 124 and 125,
The first and second oil return passages 132 and 1 are adjusted by adjusting the effective sectional areas of the flow passages in the conical holes 124 and 125.
It is configured to properly adjust the flow rate of oil flowing through each of the 33.

Flanges 101d and 101e are provided at both ends of the shock absorber body 101 in the axial direction, and mounting holes are provided in these flanges.

In FIG. 1, the shock absorber main body 101
Although the first and second end walls 101a and 101b are illustrated as being integrally formed with the peripheral wall portion 101c, the first and second end walls 101a are shown to facilitate assembly. At least one of the peripheral wall 101
It is preferable that it is formed separately from c, and the end wall formed separately is fastened to the peripheral wall portion 101c with a bolt or the like.

In the shock absorber 100 shown in FIG. 1, the slide rod 111 is connected to a drive shaft (buffered shaft) of an operating device (not shown). Here, assuming that the slide rod 111 is rapidly moved from the right side to the left side in the drawing when the switch is operated, FIG. 1 shows a state at the end of the operation. At the time when the operation of the switch is started, the buffer piston 112 has the second end wall 101.
It is located on the b side and is in a state in which the second cushioning end portion 112 c is fitted in the second cushioning orifice 104. When the operation of the switch is started, the drive shaft of the operating mechanism moves rapidly, and the slide rod 111 moves rapidly from the right side to the left side in the drawing along with the movement. In the process of this movement, the first cushioning end portion 112b of the cushioning piston 112 becomes the first cushioning end portion 112b.
In the state before entering into the buffer orifice 103, the relative flow easily occurs between the buffer piston 112 and the oil around it, so that the reaction force that acts on the buffer piston from the oil is small, and the slide rod moves quickly. Move to. From the moment when the first buffering end 112b enters the first buffering orifice 103, the pressure in the orifice 103 rises, and a reaction force that pushes back the piston 112 is generated. Since the slide rod 111 is decelerated by this reaction force, the impact applied to the drive shaft of the operating mechanism connected to the rod 111 is alleviated. First cushioning end 11
When 2b enters the first buffer orifice 103 and the pressure in the orifice rises, the oil in the orifice 103 is returned to the oil chamber 102 through the first oil return passage 132. The magnitude of the reaction force acting on the slide rod 111 is determined by the first throttle valve 130.
It can be appropriately adjusted by adjusting the flow rate of the oil that returns to the inside of the oil chamber 102 through the inside of 2.

In the above description, it is assumed that the slide rod 111 moves from the right side to the left side in the drawing when the switch is operated, but when the slide rod 111 moves from the left side to the right side when the switch is operated, the stroke thereof is changed. The second damping end portion 112c enters the second damping orifice 104 at the end of the
A reaction force acts on and a buffering action occurs. The reaction force at this time is set by the second throttle valve 131 to the second buffer orifice 104.
Can be appropriately adjusted by adjusting the flow rate of the oil returning to the oil chamber 102 side through the second oil return passage 133.

As described above, when the slide rod 111 is provided in a state where the shock absorber body 101 is penetrated, the volume of oil does not change with the movement of the slide rod 111, so that the inside of the shock absorber body 101 is not changed. There is no need to provide an air chamber at the top. Therefore, the above-mentioned shock absorbers are not restricted in their mounting postures, and those having the same structure can be used in either a vertical posture or a horizontal posture.

In each of the above examples, the first and second working end portions 112b and 112 provided at both ends of the buffer pitson 112 are provided.
Although c is tapered and the first and second buffer orifices 103 and 104 are tapered corresponding to the taper of the buffering end portions 112b and 112c, respectively, in the present invention, , A buffer having a shape in which these buffering end portions can be fitted with the one end side end and the other end side end portion of the buffering piston as the first and second buffering end portions 112b and 112c, respectively. The orifices 103 and 104 may be provided on the first and second end walls of the shock absorber body, respectively, and the shapes of the first and second working ends and the first and second shock absorbing orifices are the same as those in the above-mentioned examples. It is not limited to those shown in.

An example in which the shock absorber 100 according to the present invention is attached to an actual operating mechanism is shown in FIGS. The operating mechanism shown in FIGS. 2 and 3 is for operating a circuit breaker, and is disclosed in Japanese Examined Patent Publication No. 6-58777 and Japanese Utility Model Publication No. 6-105.
It is a publicly known one disclosed in Japanese Patent Publication No. 89 and the like. In FIG. 2, 1 is a frame for fixing an operating device, 2 is a closing spring fixed to the frame 1, 3 is a link mechanism attached to the frame 1, 4 is a blocking spring fixed to the frame 1, and 6 is An accumulating mechanism for accumulating the closing spring, and 7 is an output shaft. Of the shafts that support the links that form the link mechanism 3, the shafts indicated by black circles are fixed to the frame 1. The output shaft 7 is connected to a movable contactor of a circuit breaker (not shown) through an appropriate connection mechanism, and the output shaft 7 is urged by the closing spring 2 and the breaking spring 4 when closing and breaking the circuit breaker, respectively. 7 is driven counterclockwise and clockwise in the drawing.

During the throwing operation, the half-moon hacker 30 for throwing
g is pulled out and the input hacker 30f and the latch roller 30
The engagement with h is released, the plunger rod 8 is projected to the right in the drawing, and the slider 9 is moved to the right in the drawing.
The displacement of the slider 9 is transferred to the output shaft 7 via the link mechanism 3.
To rotate the output shaft 7 in the counterclockwise direction and displace the plunger rod 43 connected to the cutoff spring 4 leftward in the drawing to store energy in the cutoff spring 4. By rotating the output shaft 7 in the counterclockwise direction, the movable contactor of the circuit breaker (not shown) is displaced toward the fixed contactor to perform the closing operation. When the closing operation is completed and the storage of the breaking spring 4 is completed, the latch roller 32 engages with the notch 33a provided at the tip of the closing holding hacker 33 to hold the breaker in the closed state and Hold in a stored state.

When the closing operation of the circuit breaker is completed, the end portion of the closing hacker 30f separates from the limit switch LS1, so that the limit switch LS1 operates. When the limit switch LS1 operates, the electric motor 63 is started. When the closing operation is completed, the plunger rod 8
One end portion 27a of the long groove 27 provided at the end portion of the connecting rod 26 provided at the end abuts on the moving pin 68 fixed to the drive lever 61 and slidably fitted in the long groove 27. ing. At this time, the drive lever 61 is in the position shown.

When the electric motor 63 rotates, the gears 64 and 6
The hoisting gear 66 is driven via 5 and the gear 66 is rotated counterclockwise in the drawing. When the hoisting gear 66 rotates, the drive pin 67 fitted in the arcuate elongated hole 69 provided in the hoisting gear 66 is displaced downward together with the gear 66, so that the drive lever 61 is drawn. Turn counterclockwise. As a result, the connecting rod 26 is displaced to the left to store the closing spring 2. When the hoisting gear 66 makes a half rotation and the drive pin 67 reaches the bottom dead center, the charging of the closing spring 2 is completed. The urging force of the closing spring 2 is retained by being locked by the closing hacker 30f, and the energy storing process of the closing spring 2 ends. Immediately after the charging of the closing spring is completed, the drive pin 67 moves along the elongated hole 69 and returns to the top dead center.

When the circuit breaker is opened, the tripping half-moon hacker 30j is removed, and the latch roller 31i is removed from the tripping hacker 31g. remove. As a result, the breaking spring 4 is released, the output shaft 7 is rotated clockwise, and the movable contactor of the circuit breaker (not shown) is separated from the fixed contactor.

Since the operating mechanism shown in FIGS. 2 and 3 is already known, the detailed description of the configuration and the detailed operation will be omitted.

In the operating mechanism shown in FIGS. 2 and 3, the plunger rod (driving shaft of the operating mechanism) 43 rapidly moves to the right in the drawings by the release of the breaking spring 4 when the breaking operation is performed. However, at the end of the breaking operation, the rod 4
Since a large shock is applied to the shock absorber 3, the shock absorber 100 according to the present invention is used to reduce the shock.

In the example shown in FIG. 2, the second end wall 101 of the shock absorber body 101 is provided at the end of the case 401 of the cutoff spring 4.
The shock absorber 100 is secured by bolting the end on the b side.
Is attached to the blocking spring 4. In the illustrated example, the end portion of the plunger rod 43 is extended and introduced as it is as the slide rod 111 of the shock absorber into the shock absorber, and the shock absorbing piston is attached to the rod. According to this structure, it is not necessary to provide a means for connecting the slide rod of the shock absorber to the shaft to be buffered, so that the operating mechanism can be downsized.

In the example shown in FIG. 2, when the plunger rod 43 moves rightward during the shutoff operation, the shock absorber 1
The buffer piston 112 in 00 moves to the second end wall 101b side to perform the buffer operation.

In the example shown in FIG. 3, the shock absorber 100 according to the present invention is arranged coaxially with the coil spring 400 inside the coil spring 400 housed in the case of the breaking spring 4.
The end portion of the shock absorber body on the first end wall 101a side is fixed to one end of the case 401 of the blocking spring. Also in this example, the plunger rod 43 of the breaking spring is used as it is as the slide rod 111 of the shock absorber.

In the present invention, since it is not necessary to provide an air chamber in the shock absorber main body, the outer diameter dimension of the shock absorber main body can be reduced and the shock absorber can be made compact. Therefore, the shock absorber according to the present invention can be easily incorporated inside the operation mechanism (inside the blocking spring 4 in the illustrated example) as in the example shown in FIG.

Although the shaft to be buffered (plunger rod 43) itself is used as the slide rod 111 of the shock absorber in the examples shown in FIGS. 2 and 3, the present invention is limited to such a structure. Instead of this, the slide rod of the shock absorber and the buffered shaft of the operating mechanism may be separately provided, and the slide rod and the buffered shaft may be connected by a connecting means.

[0053]

As described above, according to the present invention, an air chamber for absorbing a change in volume of oil is provided in the shock absorber body by providing the slide rod with the shock absorber body being penetrated. Since it is not necessary, there is an advantage that the shock absorber main body can be made compact and the shock absorber can be made compact.

Further, according to the present invention, since the air chamber is not provided in the shock absorber main body, the same shock absorber can be mounted in either the horizontal direction or the vertical direction. Therefore,
The same shock absorber can be applied to the operating mechanisms having different directions of the shaft for shock absorption, and the cost can be reduced by standardizing the constituent parts of the shock absorber.

Further, in the present invention, when the throttle valve for adjusting the flow rate of the oil returning through the oil return passage is provided, the throttle valve is adjusted to adjust the reaction force that contributes to the cushioning action. Therefore, there is an advantage that the buffering effect can be adjusted appropriately.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration example of a shock absorber according to the present invention.

FIG. 2 is a configuration diagram showing an example of an operating mechanism to which a shock absorber according to the present invention is attached.

FIG. 3 is a configuration diagram showing another example of an operating mechanism to which a shock absorber according to the present invention is attached.

FIG. 4 is a cross-sectional view showing a conventional shock absorber.

[Explanation of symbols]

 100 shock absorber 101 shock absorber main body 102 oil chamber 103 first shock absorbing orifice 104 second shock absorbing orifice 111 slide shaft 112 shock absorbing piston 112a piston main body 112b first shock absorbing end 112c second shock absorbing end 132 first Oil return passage 133 Second oil return passage 135 Buffer oil 137 Oil return passage

Claims (3)

[Claims] 1. An oil chamber is formed inside and a first chamber is provided at one end and at the other end of the oil chamber in the axial direction.
And first and second openings in the oil chamber on the second end wall
A shock absorber main body each having a shock absorber orifice formed therein, and a shock absorber main body that is provided so as to extend in the axial direction of the oil chamber through the first and second end walls of the shock absorber main body. A slide rod slidably supported with respect to the slide rod, fixed to the slide rod so as to move together with the slide rod inside the shock absorber main body, and an end portion on one end side and an end portion on the other end side. A first and a second cushioning piston having a shape capable of being fitted in the first cushioning orifice and the second cushioning orifice, respectively, and the first and second cushioning pistons. An oil return passage for returning the oil that has flowed out from the buffer orifice into the oil chamber, wherein the first working end and the second working end of the buffer piston are respectively the first and second working ends. Loose The buffer piston and the oil, rather than the gaps formed between the inner peripheral surfaces of the first and second buffer orifices and the first and second working ends when fitted in the impact orifice. The inner diameter of the oil chamber and the inner diameters of the first and second buffer orifices are set so that a gap formed between the oil chamber and the inner circumference of the chamber becomes larger. A buffer for a switch operating mechanism, wherein the buffer orifice and the oil return passage are filled with oil. 2. The first and second buffering orifices are formed in a shape in which the inner diameter gradually increases toward the first and second buffering end portions of the buffering piston, respectively. The shock absorber for a switch operating mechanism according to claim 1, wherein the first and second shock-absorbing end portions are formed in a shape in which the diameter gradually decreases toward the first and second shock-absorbing orifices, respectively. 3. The shock absorber for a switch operating mechanism according to claim 1, wherein an adjustable throttle valve is provided in the middle of the oil return passage.