JPH0341136Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cylinder device having a speed control mechanism, and more specifically, to a cylinder device having a speed control mechanism, and more specifically, when performing a predetermined operation using a fluid pressure cylinder, the piston in the cylinder is rapidly moved to a predetermined position. Even if it is,
The present invention relates to a cylinder device having a speed control mechanism configured to stop effectively and without impact at the end of a stroke.

Generally, when moving an object in conjunction with the piston of a fluid pressure cylinder, if the piston moves at normal speed to the end of its stroke, a very large impact will be applied to the object due to inertia, etc. Alternatively, the hydraulic cylinder may be damaged and generate noise. Therefore, it is necessary to reduce the impact of the transferred object at the end of its stroke by reducing the moving speed of the piston near the end of its stroke.

For this reason, a speed control device as exemplified in FIG. 1 has conventionally been used. That is, this speed control device has a passage 12 extending from a switching valve 4 connected to a pressure source 2, and a tip thereof connected to a piston 6.
One chamber 10 in the cylinder 8 partitioned by
is connected to. On the other hand, a passage 18 extends from the other chamber 14 in the cylinder 8 and is connected to a flow rate control valve 16 . In this case, flow control valve 1
6 to the switching valve 4, and the flow rate control valve 16 is provided with a passage 26 that is opened and closed by a main valve 24 attached to a diaphragm 22. A coil spring 30 is disposed inside the chamber 28 partitioned by the diaphragm 22, and the diaphragm 22 is pressed under the action of the spring 30. Also, passage 26
is provided with a valve 33 that is constantly pressed upward by a coil spring 31, and this valve 33
A truncated conical valve 38 is provided in the space defined in the center of the
The distal end portion of the front end faces to define a side passageway 34. On the other hand, the passage 12 branches into a passage 40 on the way, and a speed controller 46 consisting of a variable throttle valve 42 and a check valve 44 is installed at one end of the passage 40.
has been set up. Further, a passage 48 is connected from the speed controller 46 to the chamber 28 .

The operation of such a conventional speed control device is as follows.

First, pressure fluid supplied from the pressure source 2 passes through the switching valve 4 and the passage 12 and is introduced into the chamber 10, thereby causing the piston 6 to move in the direction of the arrow. As a result, the fluid in the chamber 14 is sequentially sent out of the apparatus through the passage 18, the flow rate control valve 16, the passage 20, and the switching valve 4. At this time, the pressure fluid in the passage 12 is led to the chamber 28 defined by the diaphragm 22 via the passage 40, the variable throttle valve 42, and the passage 48, so the fluid pressure in the chamber 28 gradually increases. . When the fluid pressure exceeds the set pressure, the diaphragm 22 is displaced and the main valve 24 is lowered in the figure to close the passage 26. Therefore, after that, the piston 6 moves in response to the flow rate of the fluid passing through the side passage 34 throttled by the valves 33 and 38, so its movement speed becomes low.

Therefore, in the speed control device, the deceleration start position of the piston 6 is determined by the degree of increase in the fluid pressure in the chamber 28. In other words, when the piston 6 performs a plurality of displacement strokes, the piston is always moved from a predetermined position. 6, the degree of pressure increase must be the same each time. However, the degree of this pressure increase depends on changes in the fluid temperature, changes in the frictional force applied to the piston 6, changes in load due to changes in the transferred object (not shown) connected to the piston rod, and the accuracy of the variable throttle valve 42. It is significantly influenced by various factors. Therefore,
In fact, the piston 6 cannot always be decelerated from a predetermined position, and the object to be transported cannot be moved appropriately.

In addition, there are speed control devices that use a mechanically operated valve operated by a cam using the mechanical movement of a piston, and speed control devices that control electrically using reed switches, limit switches, etc. There are many elements and the manufacturing process is complicated, so all conventional devices have high manufacturing costs, and devices that are electrically controlled naturally have drawbacks such as the need to install a dedicated electric circuit. Was.

The present invention has been made to overcome the above-mentioned disadvantages, and is provided with a hole in the side wall of the liquid pressure cylinder that communicates with the space within the stroke range of the piston, and the liquid pressure derived from the hole is It is configured to effectively utilize the change to throttle the liquid pushed out from the cylinder, and to obtain stroke reproducibility that reliably decelerates the piston from a predetermined position. It is an object of the present invention to provide a cylinder device having a speed control mechanism that prevents excessive impact at the end of a stroke.

In order to achieve the above object, the present invention provides a cylinder in which fluid is alternately supplied from first and second holes to both chambers partitioned by a piston of a fluid pressure cylinder to move the piston. A third hole is formed in the side wall of the
A flow control valve is connected to the hole and the third hole, a first chamber and a second chamber are defined inside the flow control valve by a diaphragm, and the first chamber and the second chamber are separated by a diaphragm. 3, the stopper member is arranged to freely face the first chamber, while the second chamber is connected to the pressure fluid supply source, and a diaphragm is elastically arranged inside the second chamber. A pressing coil spring is provided to maintain the same pressure in the first chamber and the second chamber before the piston passes through the third hole, and after the piston passes through the third hole, the pressure in the first chamber and the second chamber is maintained at the same pressure. In the meantime,
Supply pressure is supplied to the first chamber of the flow control valve through the third hole to release the diaphragm from the restriction of the stopper member, and a main valve provided in the diaphragm opens a passage communicating with the second hole. Blocked and second
It is characterized by increasing the internal pressure on the hole side and applying a cushioning action to the piston.

Next, preferred embodiments of a cylinder device having a speed control mechanism according to the present invention will be described in detail with reference to the accompanying drawings.

The cylinder device having a speed control mechanism according to this embodiment includes a switching valve 50 and a speed controller 5.
2. Consists of a flow control valve 54, a fluid pressure cylinder 56, and a plurality of passages.

The switching valve 50 is a directional control valve for switching the flow direction of the fluid supplied from the pressure source 58. The speed controller 52 is a variable throttle valve 60
and a check valve 62.

The flow control valve 54 has a first
defining a port 63 and a second port 64;
Approximately L-shaped passages 66 and 68 are provided that communicate the ports 63 and 64, respectively. A small diameter side passage 70 that communicates the passage 66 and the passage 68 is provided in the lower part of the body, and a variable throttle valve 72 is connected to this side passage 70.
to appear. A relatively large chamber communicating with the passages 66 and 68 is defined in the center of the body, and one end of the passage 68 is formed into a tubular shape, and a part of the coil spring 74 is fitted around the tubular partition wall 67. . Furthermore, a diaphragm 78 integrally formed with a truncated conical main valve 76 is provided to separate the chamber into a first chamber 80 and a second chamber 82 . The main valve 7
6 opens and closes one end of the passage 68, and a coil spring 74 is brought into contact with this. Also,
A passage 84 communicating with the chamber 82 and a hole 86 are bored, and a portion of the hole 86 is provided with an internal thread. Furthermore, a stopper member 88 consisting of a flange 87a and a columnar part 87b partially provided with a screw is screwed into the hole 86, and a handle 90 is attached to the columnar part 87b. In this case, only when the fluid pressure in the chamber 82 becomes high and the difference between the fluid pressure in the chamber 80 and the fluid pressure in the chamber 80 exceeds a predetermined pressure, the main valve 76 is displaced and closes the passage 68; is the coil spring 74
It is configured to abut against the flange 87a and open the passage 68 by the elastic force of the flange 87a.

On the other hand, a piston 92 that slides airtight is housed in the cylinder 56, and a piston rod 94 is provided on the piston 92. That is, the object to be transferred (not shown) is mechanically connected to the piston rod 94 and interlocks with the piston 92.

Holes 96 and 98 for fluid entry and exit are bored near both ends of the cylinder 56, and the respective chambers 100 and 102 of the cylinder 56 are partitioned by a piston 92.
Get passage to the fluid against. Furthermore, piston 9
A hole 104 for leading out the pressure fluid under the action of the displacement of the cylinder 56 is bored in the side wall portion extending in the longitudinal direction of the cylinder 56. In this case, the hole 104 is configured to be within the stroke range of the piston 92.

In addition, a passageway is provided to connect the above-mentioned components. That is, a passage 106 from the pressure source 58 to the switching valve 50 is provided, a passage 108 from the switching valve 50 to the passage 66 of the flow control valve 54, and a passage 110 from the switching valve 50 to the speed controller 52 are provided. On the other hand, a passage 1 leading from the speed controller 52 to the hole 96 of the cylinder 56
12, and a passage 114 communicating from the passage 84 of the flow control valve 54 to the hole 104 in the cylinder 56;
A passage 116 is provided that communicates the passage 68 of the flow control valve 54 and the hole 98 of the cylinder 56.

The cylinder device having the speed control mechanism according to the present invention is basically constructed as described above.Next, the operation and effects of the device will be explained.

First, when moving the piston 92 in the direction of arrow A at the position shown in FIG.
Further, the fluid is introduced into the chamber 100 through the passage 110, the speed controller 52, the passage 112, and the hole 96 in order.The introduced fluid presses the piston 92 and moves it in the direction of arrow A. . At this time, the chamber 102 communicates with the chamber 82 via the hole 104 and the passages 114 and 84, and also communicates with the chamber 82 through the hole 98 and the passages 116 and 68.
It also communicates with 0. Therefore, since the fluid pressures in the chambers 80 and 82 are equal, the main valve 76 opens the passage 68 without changing its initial state. Therefore, chamber 1
The fluid No. 02 is led out to the outside through the hole 98, the passages 116 and 68, the chamber 80, the passages 66 and 108, and the switching valve 50.

In this manner, piston 92 moves from its initial position in the direction of arrow A and then passes through hole 104. At this moment, the chamber 100 to which supply pressure is applied
High pressure fluid flows from the hole 104 to the passages 114, 84.
It is introduced into the chamber 82 through the. The fluid introduced into this chamber 82 passes through the diaphragm 78 and the main valve 76.
is pressed downward in the figure, and as a result, the main valve 7
6 is brought into airtight pressure contact with the tip of the annular partition wall 67 and closes the passage 68 (see FIG. 3). Therefore, after this, the fluid pushed out from the chamber 102 passes through the side passage 70 whose opening degree is throttled by the variable throttle valve 72, so the amount of fluid sent out from the chamber 102 decreases, and the piston The moving speed of 92 is reduced. In this case, since deceleration is started the moment the piston 92 passes through the hole 104, the deceleration start position is always constant. That is, the piston 92 is reliably decelerated from a predetermined position without being affected by changes in the load applied to the piston 92 or changes in the temperature of the fluid. Note that the degree of deceleration of the piston 92 is determined by adjusting the variable throttle valve 72. Can be set arbitrarily.

Next, when moving the piston 92 from the position shown in FIG. 3 to the position shown in FIG. is introduced into the chamber 80 via. At this time, since the fluid related to the supply pressure has not been introduced into the chamber 100, the fluid pressure in the chamber 82 has decreased, and the main valve 76 is displaced upward in the figure by the elastic force of the coil spring 74. aisle 68
is open to the public. Therefore, fluid supplied to chamber 80 passes through passages 68, 116 and hole 98 to chamber 102.
The piston 92 is pushed by the fluid and moves in the direction of arrow B. Note that since the fluid pressure in the chamber 82 remains the same as the fluid pressure in the chamber 80 even after the piston 92 passes through the hole 104,
Main valve 76 opens passage 68 under the action of coil spring 74 . Therefore, the piston 92 moves smoothly to the end of the predetermined stroke. In this case, by adjusting the variable throttle valve 60, the piston 92
The movement speed can be set arbitrarily.

As explained above, according to the cylinder device having the speed control mechanism of the present invention, in one stroke of the piston, the piston moves rapidly and then is reliably decelerated from a predetermined position, and in the other stroke, the piston moves rapidly. Move smoothly.
Therefore, when an object is moved back and forth using the device and the object comes into contact with another object at the end of one of the moving strokes, an effect can be obtained in that an excessive impact at the time of contact can be prevented. It will be done. Furthermore, the device has a simple configuration and is inexpensive compared to a speed control device using a mechanically operated valve, a limit switch, or the like.

Although the present invention has been described above with reference to preferred embodiments, the present invention is not limited to these embodiments, and various improvements and changes in design are possible without departing from the gist of the present invention. Of course.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a speed control device according to the prior art, FIG. 2 is an explanatory diagram of the entire device when the piston of a cylinder device having a speed control mechanism according to the present invention is located at one stroke end, and FIG. The figure is the second
FIG. 2 is an explanatory diagram of the entire device when the piston of the device shown in the figure is located at the other stroke end. 50...Switching valve, 52...Speed controller, 54...Flow control valve, 56...Cylinder, 5
8... Pressure source, 60... Variable throttle valve, 62... Check valve, 66, 68... Passage, 70... Side passage, 7
2...Variable throttle valve, 74...Coil spring,
76...Main valve, 78...Diaphragm, 80,8
2... Chamber, 88... Stopper member, 92... Piston, 96, 98, 104... Hole.

Claims (1)

[Claims for Utility Model Registration] (1) In a cylinder in which fluid is alternately supplied from first and second holes to both chambers partitioned by a piston of a fluid pressure cylinder to move the piston, A third hole is formed in the side wall, a flow control valve is connected to the second hole and the third hole, and a first chamber and a first chamber are defined inside the flow control valve by a diaphragm. the first chamber and the third hole communicate with each other, and the stopper member is adjustable to face the first chamber, while the second chamber is connected to a pressure fluid supply source. A coil spring is provided inside the second chamber to elastically press the diaphragm, and before the piston passes through the third hole, the first
The chamber and the second chamber are maintained at the same pressure, and while the piston reaches the second hole after passing through the third hole, the third chamber is kept at the same pressure.
Supply pressure is supplied to the first chamber of the flow control valve through the hole to release the diaphragm from the restriction of the stopper member, and the main valve provided in the diaphragm closes the passage communicating with the second hole. 1. A cylinder device having a speed control mechanism, characterized in that the cylinder device increases the indoor pressure on the second hole side and applies a cushioning action to the piston. (2) Utility Model Registration The cylinder device according to claim 1, which has a speed control mechanism in which the flow rate control valve is provided with a side passage, and a variable throttle valve is inserted into this side passage. (3) Utility model registration In the device according to claim 1 or 2, a speed controller is connected to the first hole of the fluid pressure cylinder, and a directional control valve is connected to the speed controller and the flow rate control valve. A cylinder device having a speed control mechanism consisting of: