JP2554241B2 - Balance device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a balance device for suspending an object to be lifted by a fluid cylinder, a string-like member or the like to make it stand still and moving the object to be lifted up and down. Regarding

[0002]

2. Description of the Related Art Conventionally, for example, in a work site such as various factories, an operator can easily raise and lower an assembly part, a jig and the like (hereinafter collectively referred to as an object to be lifted and lowered) with a slight force. In addition, there is used a balance device that suspends a lifted body in a weightless state by an air cylinder and a pressure adjusting mechanism.

As shown in FIG. 14, this balancing device P
1, the piston rod P5 of the air cylinder P3
Attach the lifted body W to the tip of the
By 7, the cylinder chamber P9 of the air cylinder P3 is adjusted to a pressure that opposes the gravity acting on the lifted object W, and the lifted object W is stopped and kept in a weightless state. Then, in this state, the worker can raise and lower the lifted body W by directly applying a force to the lifted body W.

[0004]

However, in the case of the conventional balance device P1 described above, since the lifted body W is directly connected to the piston rod P5 of the air cylinder P3, the sliding resistance during the operation of the air cylinder P3 is increased. There is a problem in that the operator cannot easily move up and down the object W to be lifted because of the burden of pressure resistance and pressure resistance. That is, in the balance device P1 described above, when the piston P11 is moved, the contact portion between the O-ring P13 of the piston P11 and the cylinder inner wall P15, the contact portion between the piston rod P5 and the metal P17, and the like are relatively large. Sliding resistance is generated, and pressure resistance is also generated due to pressure fluctuations in the cylinder chamber. Therefore, the worker applies a force sufficient to overcome these sliding resistance and pressure resistance to the lifted / lowered body W.
Therefore, there is a problem in that it is not possible to pull down the lifted body W with a sufficiently small force.

In addition to the above-mentioned problems, in the above balancing apparatus P1, the lifted / lowered body W is the piston rod P.
5, the air cylinder P3 having a long stroke is used in order to increase the lifting distance of the object W to be lifted.
However, there is a problem that the device becomes large in size.

In order to solve this problem, it is possible to reduce the load due to sliding resistance during cylinder operation, to easily pull down the lifted body with a slight force, and to downsize the entire apparatus. I thought of a balance device that can do it.

That is , a fluid cylinder having a pulley attached to the tip of a piston rod and a string-like body having a free end to which a lifted body is fixed and the other end fixed to a predetermined location are provided.
The pulley is installed so as to function as a moving pulley in the suspension path of the lifted body by the string-like body, and the cylinder chamber of the fluid cylinder is regulated to a pressure that opposes the gravity of the lifted body. I considered a balance device equipped with pressure adjusting means for stopping the piston .

In the balance device having the above structure, the piston is stopped by adjusting the pressure in the cylinder chamber of the fluid cylinder to the pressure that opposes the gravity of the lifted body by the pressure adjusting means. As a result, the lifted / lowered body that is fixed to one end of the string-shaped body and suspended is made to stand still in a weightless state. Then, for example, if the operator lifts or pulls the lifted body, the lifted body can be easily moved up and down.

When the object to be lifted and lowered is moved up and down, the pulley, which is incorporated so as to function as a moving pulley, moves, and along with this, the piston rod, and thus the piston, moves. 1 / m
The amount is reduced to 2 or 1/4. Therefore,
Therefore, the force to move the piston rod is small,
The burden due to sliding resistance and pressure resistance generated during cylinder operation (piston movement) is reduced, and the lifted body can be easily pulled down with a slight force.

Further, since the moving distance of the piston as above mentioned is reduced, it is possible to use a short-stroke compact fluid cylinder, it is possible to miniaturize the apparatus. As a method of incorporating the pulley into the string, the string may be directly hung on the pulley, or the string may be hung on the intermediate portion of the string without directly hanging the string on the pulley. It may be configured to function as a moving pulley as a whole by being connected to another moving pulley.

Here, in the balance device , since the lifted body is stopped by adjusting the pressure of the fluid cylinder using the pressure adjusting means, when the pressure adjusting means causes an abnormality in the pressure adjustment of the cylinder chamber. , For example, when the supply of fluid from the fluid supply source to the fluid cylinder is stopped,
The pulley may move and the suspended object to be lifted may fall. Therefore, such in order to prevent inconvenience, it is desirable to have a fall preventing means for preventing the dropping of the lifting body when abnormality occurs in the pressure regulating of the cylinder chamber by prior Kicho圧means. With this configuration, even if the pressure regulation in the cylinder chamber is abnormal,
The fall prevention means prevents the lifted body from falling, which is very preferable for safety.

[0012] Incidentally, as the fall prevention means can be adopted a braking means for clamping the piston rod before Symbol fluid cylinder. With such a configuration, the lifted body can be reliably prevented from falling by clamping the piston rod.

Further, as a more specific configuration of the brake means are pre SL branched from the fluid supply source for supplying a fluid to the fluid cylinder supply fluid pressure, is the brake release state by the fluid pressure at all times On the other hand, when the fluid pressure is released, it is possible to employ a braking means configured to clamp the piston rod and bring it into a braking state. According to this, even if the supply of the fluid from the fluid supply source is stopped for some reason, the fluid pressure supplied to the brake means will be released accordingly, so that the piston rod is clamped. It is possible to reliably prevent the lifted body from falling.

[0014] Here, if the state in which the supply of fluid from the fluid supply source is stopped, performing start to pressure regulation again the supply of fluid to the cylinder chamber of the fluid cylinder, the fluid in the brake unit Since the pressure is supplied, the brake means shifts from the brake state to the brake release state . However, if the rate of increase in the fluid pressure supplied to the braking means is too fast, the brake is released before the fluid pressure supplied to the cylinder chamber rises sufficiently, and the lifted body falls, which is not preferable.

[0015]

Means for solving the problems, the effect of action and the Invention In order to prevent such inconveniences, balance of the present invention
The device is provided with a suppressing means for suppressing the rising speed of the fluid pressure supplied from the fluid supply source to the braking means in the middle of the flow path connecting the braking means and the fluid pressure supply source . . According to this, the brake release can be delayed by delaying the rise of the fluid pressure supplied to the brake means by the suppressing means, so that the lifted body is prevented from being accidentally dropped at the start of air supply. be able to.

[0016]

EXAMPLES Before describing the examples of the present invention, reference will be made to the present invention.
Descriptions of consideration examples (first to eighth reference examples) based on the drawings
I do. These reference examples are examples of the braking means and the suppression device of the present invention.
It relates to a balancer that has no control means.
It First, a first reference example of the present invention will be described with reference to FIG. As shown in FIG. 1, the balance device 1 of the first reference example.
Includes an air cylinder 15 provided with a rope 11 for suspending the lifted object W and a moving pulley 13, and as an air pressure adjusting mechanism for adjusting the pressure of the air cylinder 15 to keep the lifted object W in a weightless state. A main valve 17 communicating with the cylinder 15 and a regulating valve 19 for controlling the main valve 17.
It has and.

Next, the structure of the air cylinder 15 will be described in detail. The air cylinder 15 is suspended from a ceiling 21 and fixed horizontally, and a piston 25 is slidably accommodated in a cylinder body 23. A cylinder pressure adjusting chamber 27, which is a cylinder chamber on the right side of the piston 25, communicates with a main valve 17, which will be described in detail later, and is adjusted to a pressure that opposes the gravity acting on the lifted body W. An exhaust chamber 28, which is a cylinder chamber on the left side of the piston 25, is directly opened to the atmosphere via an exhaust port 29.

A piston rod 31 is integrally attached to the piston 25. The piston rod 31 is provided on the metal 2 of the left end wall portion 23a of the cylinder body 23.
3b is penetrated and protruded to the outside, and the tip portion 31a thereof
A movable pulley 13 is rotatably supported by the shaft. Also,
A fixed pulley 32 is rotatably supported on the lower side of the left end wall portion 23a of the cylinder body 23. The rope 11 is fixed to the fixed portion 23c on the upper side of the left end wall portion 23a of the cylinder body 23. This rope 11
The fixed pulley 3 is mounted on the movable pulley 13 and the fixed pulley 32.
The object to be lifted W is attached to the tip (free end) 11a hung from 2
Has been fixed. The movable pulley 13 moves in the left-right direction in the drawing together with the piston rod 31 when the lifted body W is lifted and lowers, and functions as a movable pulley in the suspension path of the lifted body W by the rope 11. Is built in.

Next, the structure of the main valve 17 will be described in detail.
The main valve 17 communicates with the air supply source S inside the casing 41 in order from the bottom of FIG.
Is accommodated, a pressure adjusting chamber 47 communicating with the air cylinder 15, an atmosphere, and an exhaust valve body 49.
And an piston chamber 55 for accommodating the pressure adjusting piston 53.

The air supply chamber 45 has an air supply port 57,
Air supply source S via pressure reducing valve 59 and air pressure filter 61
And is constantly supplied with air of a predetermined pressure. In addition, the air supply valve body 43 is accommodated in the air supply chamber 45 so as to be movable in the vertical direction.
Is always urged upward by the spring 63 to be seated on the air supply valve seat 65 protruding in an annular shape.

The pressure adjusting chamber 47 includes an air supply valve body 43 and an exhaust valve body 4.
It is partitioned by 9 and 9, and communicates with the cylinder pressure regulating chamber 27 of the air cylinder 15 through the pressure regulating port 67, and also communicates with the regulating valve 19 described later through the regulating port 69. The exhaust chamber 51 is open to the atmosphere via the exhaust port 71. Further, in the exhaust chamber 51,
An exhaust valve body 49 is housed so as to be movable up and down, and the exhaust valve body 49 is always urged downward by a spring 73 to be seated on an exhaust valve seat 75 projecting in an annular shape. .

In the piston chamber 55, the pressure adjusting piston 53 is housed so as to be vertically slidable, and the pressure adjusting piston chamber 77 above the pressure adjusting piston 53 and the control chamber 7 below it.
It is divided into 9 and. Of these, the pressure regulating piston chamber 77
Communicates with the regulating valve 19 via the pressure regulating port 81 and is open to the atmosphere via the bleed port 83 and the orifice 85. Further, the control room 79 has a bypass 8
It communicates with the pressure regulation chamber 47 through 7.

A piston rod 91 is integrally fixed to the pressure adjusting piston 53 housed in the piston chamber 55. The piston rod 91 slidably penetrates through the partition wall 93 and the exhaust valve body 49 and extends to the pressure regulating chamber 47. The pressure regulating chamber 47 has a large outer diameter. A diameter portion (stem) 95 is formed. The large-diameter portion 95 pushes down the air supply valve body 43 and separates it from the air supply valve seat 65 in accordance with the up-and-down movement of the pressure adjusting piston 53.
It serves to lift the exhaust valve element 49 and separate it from the exhaust valve seat 75.

Next, the structure of the adjusting valve 19 will be described in detail. The adjusting valve 19 includes a back pressure chamber 10 in which a pressure adjusting spring 103 is arranged in the casing 101 in order from the right side of FIG.
5, the sub-control chamber 109 partitioned from the back pressure chamber 105 by the diaphragm 107, the sub-pressure regulating chamber 111 communicating with the pressure-regulating piston chamber 77 of the main valve 17, and the air supply chamber 45 of the main valve 17. A sub air supply chamber 113 that communicates is provided.

Here, the back pressure chamber 105 is open to the atmosphere through the exhaust port 115. Also, this back pressure chamber 105
The pressure-adjusting spring 103 arranged in the inside is the diaphragm 107.
For biasing the sub-control chamber 109 side (the left side in the figure) to the spring receiving portion 117 at the center of the diaphragm 107.
And the spring receiving portion 121 of the handle screw 119 screwed and inserted into the right end wall of the casing 101. Therefore, the force with which the pressure adjusting spring 103 urges the diaphragm 107 rotates the handle screw 119, and
It can be adjusted by moving 21 to the right or left and changing the amount of deflection of the pressure adjusting spring 103.

The sub control chamber 109 communicates with the pressure regulating chamber 47 of the main valve 17 via the flow passage 123, and plays a role of moving the diaphragm 107 by the air pressure applied from the pressure regulating chamber 47. The sub pressure regulation chamber 111 communicates with the pressure regulation piston chamber 77 of the main valve 17 via the flow path 125. The flow channel 125 and the above-mentioned flow channel 123 are connected via an orifice 127. The orifice 127 is normally closed except in a special case described later.

The sub air supply chamber 113 is the air supply chamber 45 of the main valve 17.
And is constantly supplied with air having a predetermined pressure. A sub valve body 129 is provided in the sub air supply chamber 113 so as to be movable left and right. The shaft portion 131 of the sub valve body 129 is slidably inserted into the partition wall 133, and the sub valve body 129 is urged to the right side in the drawing by the spring 135 to be seated on the sub valve seat 137. In addition, the sub valve body 12
The tip portion 139 of the shaft portion 131 of the nine protrudes into the sub control chamber 109, and the tip portion 139 is pressed by the spring receiving portion 117 of the diaphragm 107 to separate the sub valve body 129 from the sub valve seat 137. Is configured to be able to.

Next, the operation of the balance device 1 having the above-mentioned structure will be described. In the balancing device 1 of the first reference example, the lifted body W is attached to the tip end 11a of the rope 11 provided in the air cylinder 15 to hang it, and the handle screw 119 of the adjusting valve 19 is turned to rotate the air cylinder 15 The cylinder pressure adjusting chamber 27 is adjusted to a pressure that opposes the gravity acting on the object W to be lifted, and the object W to be lifted is held stationary to maintain a weightless state. Here, the lifted body W
The detailed operations of the main valve 17 and the adjusting valve 19 and the like when maintaining the weightless state are as described in (1) to (9) below.

(1) When the lifted body W is attached to the rope 11, the rope 11 is pulled downward by the weight of the lifted body W, and the movable pulley 13 and thus the piston 25 are pushed to the right. (2) Next, turn the handle screw 119 of the adjusting valve 19,
When the diaphragm 107 is pushed to the left by the urging force of the pressure adjusting spring 103, the sub valve body 129 is pushed to the left and the sub valve seat 1
Separated from 37. Therefore, the auxiliary pressure adjusting chamber 111 and the auxiliary air supplying chamber 113 are communicated with each other, compressed air is supplied to the pressure adjusting piston chamber 77 of the main valve 17, and the pressure rises.

(3) Due to the pressure increase in the pressure adjusting piston chamber 77, the pressure adjusting piston 53 of the main valve 17 moves downward, and the air supply valve body 43 is pressed downward by the large diameter portion 95 of the piston rod 91. And is separated from the air supply valve seat 65.
Therefore, the air supply chamber 45 and the pressure regulation chamber 47 communicate with each other, and the pressure regulation chamber 4
Since the compressed air is supplied to 7 and the pressure rises, the pressure in the cylinder pressure adjusting chamber 27 of the air cylinder 15 rises, and the piston 25 generates a leftward advancing force.

(4) Further, as the pressure in the pressure adjusting chamber 47 increases, the sub control chamber 10 of the adjusting valve 19 communicating with the pressure adjusting chamber 47.
Since the pressure of 9 also rises, the diaphragm 107 is pushed rightward against the biasing force of the pressure adjusting spring 103. Then, when the sub control chamber 109 reaches a predetermined pressure, the sub valve body 129 is seated on the sub valve seat 137 again, and the communication between the sub pressure regulating chamber 111 and the sub air supply chamber 113 is cut off. Then, compressed air is not supplied to the pressure regulating piston chamber 77 of the main valve 17, and the internal air is gradually exhausted from the bleed port 83 to the atmosphere and the pressure drops.

(5) As described above, the pressure in the pressure-adjusting piston chamber 77 drops and the pressure-adjusting chamber 47 described in (3) above.
Control chamber 7 communicating with pressure regulating chamber 47 as the pressure of
Since the pressure of 9 rises, the pressure regulating piston 53 starts to rise. (6) Due to the rise of the pressure adjusting piston 53, the air supply valve body 43 rises and is seated on the air supply valve seat 65, and further, the exhaust valve body 49 is lifted by the large diameter portion 95 and the exhaust valve seat 75.
Be farther apart. Therefore, the pressure regulating chamber 47 is shut off from the air supply chamber 45 and communicates with the exhaust chamber 51.
Is exhausted from the exhaust port 71, and the pressure in the pressure regulating chamber 47 once begins to drop.

(7) Due to the pressure drop in the pressure adjusting chamber 47, the sub control chamber 109 of the adjusting valve 19 communicating with the pressure adjusting chamber 47.
Since the pressure of the auxiliary valve body 12 is also lowered, the diaphragm 107 is pushed to the left by the urging force of the pressure adjusting spring 103, and the auxiliary valve body 12 is again pressed.
9 is separated from the sub valve seat 137. Therefore, compressed air is supplied to the pressure adjusting piston chamber 77 and the pressure rises, so that the pressure adjusting piston 53 moves downward again, the exhaust valve body 49 is seated, and the air supply valve body 43 causes the air supply valve 43 to move. Separated from the seat 65. Therefore, the pressure in the pressure regulating chamber 47 rises again, the pressure in the cylinder pressure regulating chamber 27 rises, and the piston 25 is moved to the left.

(8) Then, the pressure regulating piston chamber 77 of the main valve 17 and the control chamber 79 are brought into an equilibrium state via the pressure regulating piston 53 while repeating the above-mentioned operations (2) to (7). The pressure regulating chamber 47 and thus the cylinder pressure regulating chamber 27 of the air cylinder 15 are maintained at a predetermined pressure.

(9) As is apparent from the above operation, the pressure in the pressure regulating chamber 47 of the main valve 17 (that is, the pressure in the cylinder pressure regulating chamber 27) is determined by the handle screw 119 of the regulating valve 19.
The amount by which the pressure regulating spring 103 is rotated by the diaphragm 107
It is possible to freely adjust the pressure of the cylinder pressure adjusting chamber 27 by rotating the handle screw 119 by an appropriate amount so that the pressure in the cylinder pressure adjusting chamber 27 is applied to the piston 25 by the gravity acting on the lifted body W. The piston 25 can be stopped by setting the pressure so as to counteract the advancing force.
The lifted body W can be made stationary and kept in a weightless state.

The above-mentioned orifice 127 is normally closed, but when the supply / exhaust operation of the main valve 17 is sensitive, a small amount of the orifice 127 is opened to adjust the pressure regulating chamber 47 and the pressure regulating piston chamber 77. By communicating with, the operation of the main valve 17 can be stabilized. Then, with respect to the object W to be lifted and held in the weightless state as described in (1) to (9) above,
The worker himself / herself directly applies a force to the object W to be lifted / lowered.
Can be moved up and down, but with the up-and-down movement, the moving pulley 13 moves in the left-right direction in the drawing, and the piston rod 31 and the piston 25 move accordingly. Therefore, when the lifted / lowered body W is raised / lowered by 2α,
The moving distance of the piston 25 is reduced to half (that is, α) of the moving distance of the lifted body W. Therefore, the force for moving the piston 25 is correspondingly small, and the load caused by sliding resistance and pressure resistance generated during cylinder operation (when the piston 25 is moving) is reduced, so it is possible to easily move up and down with a slight force. The effect is that you can pull down your body.

Further, according to the first reference example , since the moving distance of the piston 25 is reduced as described above, a small air cylinder 28 having a short stroke can be used,
There is an effect that the device can be downsized. Next, a second reference example will be described. Here, FIG. 2 is a cross-sectional view showing the pressure adjusting mechanism of the balancing device of the second reference example .

The balancing device of the second reference example, adjusting the adjusting valve 201 of the pressure mechanism, in terms of controlling the proportional solenoid 203 and plunger 205, is different from the first reference example. That is, the adjusting valve 201 of the second reference example is the same as the first reference.
Instead of the pressure adjusting spring 103 and the handle screw 119 (see FIG. 1) of the example, a proportional solenoid 203 and a plunger 205 driven by the proportional solenoid 203 are provided. In contrast, an attractive force proportional to the coil current is generated to drive the plunger 205 in the horizontal direction in the figure.
Therefore, the force with which the plunger 205 urges the diaphragm 206 is adjusted by the magnitude of the coil current.
The pressure in the pressure regulating chamber 209 of the main valve 207 can be freely set by the coil current.

Therefore, according to the second reference example as described above, the pressure adjustment of the air cylinder can be easily set by the coil current instead of manually, and the pressure adjustment mechanism is automatically controlled or remotely operated. Can be easily performed. Next, a third reference example will be described. Here, FIG. 3 is a cross-sectional view showing the pressure adjusting mechanism of the balance device of the third reference example .

The third reference example is different from the first reference example in the structure and the pressure adjusting operation of the pressure adjusting mechanism. That is, in the third reference example , the air supply chamber 303 and the pressure adjusting piston chamber 305 of the main valve 301 (similar to the first reference example ) are the orifice 30.
7, the pressure regulating piston chamber 305 is gradually supplied with air from the air supply chamber 303. In addition, the pressure regulating piston chamber 305 is provided in the auxiliary pressure regulating chamber 3 of the regulating valve 311.
It communicates with 13. Here, the structure of the adjusting valve 311 is different from that of the first reference example , and the auxiliary pressure regulating chamber 313 and the main valve 301 are different.
Communication with the pressure regulating piston chamber 305 of the diaphragm 31
The auxiliary valve element 317 is biased to the left by the valve 5, and is blocked. And the adjusting valve 311
Of the sub-control chamber 319 of the diaphragm 315
When the valve moves to the right, the sub valve body 317 is urged to the right by the spring 321 and the pressure regulating piston chamber 305 moves to the sub pressure regulating chamber 3.
The air in the pressure-adjusting piston chamber 305 is exhausted at a stroke by communicating with the pressure control chamber 13. That is, in the third reference example , the pressure of the air cylinder is adjusted by controlling the air supply to the pressure adjusting piston chamber 305 by the orifice 307.

In this way, the third pressure control mechanism is different.
Also in reference example it can provide the same effect as in the first embodiment. Next, a fourth reference example will be described. Here, FIG. 4 is a cross-sectional view showing the air cylinder and the pulley mechanism of the balance device of the fourth reference example .

The fourth reference example is different from the first reference example in that a plurality of moving pulleys are provided. That is, the balancing device of the fourth reference example is the air cylinder 401 installed vertically.
And the first attached to the tip of the piston rod 403.
The movable pulley 405 and the first suspended from the ceiling 407
A first rope 409 hung on the movable pulley 405, a second movable pulley 411 fixed to the rotating shaft of the first rope 409, and a constant pulley 413 fixed to the ceiling 407.
A second rope 415, one end of which is fixed to the ceiling and which is hung on the second movable pulley 411 and the constant pulley 413, is provided. The lifted body W is attached to the tip of the second rope. The piston rod 403 of the air cylinder 401
The cylinder pressure regulating chamber 419 on the side is regulated by the pressure regulating mechanism (main valve and regulating valve) similar to that of the first reference example to a pressure that opposes the gravity of the lifted body W.

Therefore, in the fourth reference example having such a configuration, the moving distance of the piston 417 when the lifted object W is lifted / lowered is 1 / (1) of the lifted distance of the lifted object W. It becomes 4. Therefore, in such a fourth reference example , the first reference
The air cylinder 40 that can lift and lower the object W with a lighter force than the example and has a shorter stroke.
1 has an effect that the device can be downsized.

Next, a fifth reference example will be described. Here, FIG. 5 is a cross-sectional view showing the air cylinder and the pulley mechanism of the balancing device of the fifth reference example . The fifth reference example is also the fourth
Similar to the reference example , the first point is that a plurality of moving pulleys are provided.
It differs from the reference example . That is, the balancing device of the fifth reference example is a small-diameter moving pulley 505 attached to the tip of the piston rod 503 of the air cylinder 501, and a large-diameter moving pulley 506 that rotates on the same rotation axis as the moving pulley 505.
A large-diameter fixed pulley 509 fixed to the ceiling 507, and a small-diameter fixed pulley 511 that rotates on the same rotation axis as the constant pulley 509.
With one end fixed to the rotary shaft of the constant pulley 509, a small diameter moving pulley 505, a small diameter constant pulley 511, and a large diameter moving pulley 50.
6, Rope 5 hung in the order listed in the large diameter pulley 509
And 13 are provided.

Therefore, in the fifth reference example as described above, the moving distance of the piston 515 is ¼ of the ascent / descent distance of the lifted / lowered body W, so that the lifted / lowered body is driven with a light force as in the fourth reference example. There is an effect that the device can be downsized by using the air cylinder 501 having a shorter stroke while being able to raise and lower W.

Next, a sixth reference example will be described. Here, FIG. 6 is a cross-sectional view showing the air cylinder and the pulley mechanism of the balance device of the sixth reference example . The sixth reference example is different from the first reference example in that the lifted / lowered body W is lifted and lowered electrically instead of manually.

That is, the balancing device of the sixth reference example is the moving pulley 605 attached to the tip of the piston rod 603.
A fixed pulley 609 fixed to the ceiling 607, a rope 611 having one end fixed to the ceiling and suspended between the moving pulley 605 and the constant pulley 609, and a first gear 613 rotating integrally with the constant pulley 609. , And a second gear 615 meshed with the first gear. When the object W to be lifted and lowered is lifted, the second gear 615 is rotationally driven by a servo motor or pulse motor (not shown), The first gear and thus the constant pulley 609 are rotated. In addition, the cylinder chamber 617 of the air cylinder 601 is controlled by the pressure adjusting mechanism (main valve and adjusting valve) similar to that of the first reference example.
The pressure is adjusted to counter the gravity of the.

Therefore, in the sixth reference example , by using the pulley mechanism in which the movable pulley 605 and the rope 611 are combined, the load due to the sliding resistance and the pressure resistance can be reduced, and the driving force can be reduced. There is an effect that the lifted body W can be raised and lowered using a small motor.

Next, a seventh reference example will be described with reference to FIG. Similarly to the sixth reference example , the seventh reference example also electrically raises and lowers the lifted body W, but is different from the sixth reference example in that it is performed by a feed screw rotated by a motor.

That is, in the balancing device of the seventh reference example , the moving pulley 705 attached to the piston rod 703 of the air cylinder 701 and the rope suspended on the moving pulley 705 with one end fixed to the outer wall of the air cylinder 701. 7
09 and the tip 711 of this rope 709 is
It is fixed to an object to be lifted 715 that is vertically moved by being guided by a rod-shaped guide member 713. The lifted body 715 is screwed onto a feed screw 721 provided vertically between a ceiling 717 and a floor 719, and the feed screw 721 is rotated by a motor 727 via gears 723 and 725. Then, the lifted body 715 is moved up and down. Therefore, also in the seventh reference example , similarly to the sixth reference example , the load due to the sliding resistance and the pressure resistance is reduced, and the lifted / lowered body W is moved up and down by using the motor 727 having a small driving force. The effect is that you can.

Next, an eighth reference example will be described with reference to FIGS. 8 and 9. Here, FIG. 8 is a cross-sectional view showing the pressure adjusting mechanism of the balance device of the eighth reference example , and FIG. 9 is a cross-sectional view showing the air cylinder and the pulley mechanism. The balance device of the eighth reference example is provided with a first adjusting valve 801 and a second adjusting valve 801 ′ as shown in FIG. 8, so that as shown in FIG. Depending on the presence / absence of the transported object 807, such as when mounting and lifting
The pressure control of the air cylinder 809 can be switched.

That is, in the eighth reference example , as shown in FIG. 8, the same main valve 811 as in the first reference example and the main valve 81 are provided.
1 connected to 1 (each of the same structure as the first reference example )
The adjusting valve 801 and the second adjusting valve 801 'are provided. Here, the auxiliary air supply chambers 813 and 8 of the two adjusting valves 801 and 801 'are provided.
13 'is a main valve 811 via a 5-port 2-position valve 815.
Is connected to the air supply chamber 817. The 5-port 2-position valve 815 uses the air pressure from the air supply chamber of the main valve 811 as a pilot pressure and can be switched by two push-button 3-port 2-position valves 817 and 819. .

Therefore, in the eighth reference example having the above-mentioned structure, in the case of the state shown in FIG. 8, the sub-air supply chamber 813 of the first adjusting valve 801 is mainly operated by the 5-port 2-position valve 815. Valve 81
No. 1 air supply chamber 817 and the second adjustment valve 80
Since the communication between the auxiliary air supply chamber 813 ′ of 1 ′ and the air supply chamber 817 is cut off, the pressure of the pressure adjusting chamber 821 of the main valve 811 is controlled only by the first adjusting valve 801. Conversely, 5 ports 2
When the position valve 815 is switched from the state shown in FIG.
Since the auxiliary air supply chamber 813 ′ of the adjustment valve 801 ′ communicates with the air supply chamber 817 and the communication between the auxiliary air supply chamber 813 of the first adjustment valve 801 and the air supply chamber 817 is blocked, the main valve 811 is It will be controlled only by the second regulating valve 801 '.

Therefore, for example, the urging force of the pressure adjusting spring 823 of the first adjusting valve 801 is adjusted so that the load 807 is placed on the carrier 805 so as to be in a weightless state, and the second adjusting valve 801 'is adjusted. The pressure adjusting spring 823 ′ is attached to the transported object 807.
If it is adjusted so as to be in a weightless state when the air pressure is removed, the cylinder pressure adjusting chamber 827 of the air cylinder 809 is changed by switching the 5-port 2-position valve 815.
It is possible to easily switch the pressure adjustment for the two levels depending on the presence or absence of the transported object 807. That is, in the eighth reference example , even if the weight of the lifted body changes stepwise, there is an effect that the pressure adjustment of the air cylinder 809 can be easily switched to handle it.

Next, an embodiment of the present invention will be described with reference to FIGS. Here, FIG. 10 is a cross-sectional view showing the overall configuration of the balance device of the present embodiment , and FIG. 11 is a cross-sectional view showing the air cylinder. In addition, FIG.
13 is a cross-sectional view taken along line EE of FIG. 13, and FIG. 13 is an enlarged cross-sectional view of the brake operating portion of the air cylinder.

As shown in FIG. 10, the balance device of this embodiment has substantially the same structure as the balance device of the first reference example , but as an air cylinder, the intermediate device disclosed in Japanese Patent Laid-Open No. 5-65909. The difference is that an air cylinder 901 with a stop mechanism (brake mechanism) is used.
In the present embodiment, the same parts as the first reference example are denoted by the same codes and the first reference example, and detailed description thereof will be omitted.

The air cylinder 901 is composed of a pneumatic cylinder portion 2'and an intermediate stop mechanism portion 13 '. As shown in FIG. 11, in the pneumatic cylinder portion 2 ′, a head cover 4 ′ having ports 5 ′ and 7 ′ and an intermediate cover 6 ′ are fitted to both ends of the cylinder tube 3 ′, and the cylinder tube 3 ′ is provided. The piston 8'is slidably fitted therein, and the piston 8'has a piston rod 9 '
The piston rod 9'is slidably inserted into an insertion hole 10 'penetrating the intermediate cover 6'and extends toward the intermediate stop mechanism portion 13'. A main valve 17 and a regulating valve 19 for pressure regulation similar to those in the first reference example are provided in the port 5 '.
Is connected to the cylinder pressure regulating chamber 8a '.
Is regulated. On the other hand, the port 7 ′ communicating with the exhaust chamber 8b ′ is open to the atmosphere as it is.

The intermediate stop mechanism portion 13 'is provided with a rod cover 14' in opposition to the intermediate cover 6 '. Bosses 15 'and 16' are formed on both sides of the center of the rod cover 14 ', and an insertion hole 17' through which the piston rod 9'is inserted is formed at the center. Further, a receiving recess 18 'of the brake metal 23' is formed on the outer periphery of the insertion hole 17 'of the boss 16' so as to correspond to the receiving recess 11 'of the intermediate cover 6'.

Also, the boss portion 16 of the rod cover 14 '.
A ring-shaped convex portion 19 'is formed on the outer periphery of the surface on the ′ side, and the outer peripheral side of the convex portion 19 ′ corresponds to the receiving concave portion 12 ′ of the cylinder tube 22 ′ formed on the outer periphery of the intermediate cover 6 ′. Thus, a receiving recess 20 'is formed, and a recess 21' is formed inside. Rod cover 14 formed in this way
A cylinder tube 22 'is provided between the receiving recesses 12' and 20 'of the intermediate cover 6'and the brake metal 23' is provided between the receiving recesses 11 'and 18' of the boss 16 'and the intermediate cover 6'. Is attached. Brake metal 23 '
A split bush 24 'is externally fitted to the outer periphery of the cylinder, and a brake piston 25' is slidably installed in the cylinder tube 22 '.

The brake metal 23 'is made of a soft and wear-resistant material such as a bearing alloy, and has a piston rod 9
′ Is formed in a tubular shape having an inner diameter that can be inserted, and the slit 23a ′ is formed over the entire length in the axial direction.
Is formed so that the inner diameter thereof can be reduced.
The split bush 24 'is made of, for example, a steel material (heat-treatable) or the like, and is formed into a tubular shape that is fitted onto the brake metal 23', and has a slit 24a 'formed along its entire length in the axial direction. , The inner diameter of which can be reduced.

A brake piston 25 'is slidably guided in the piston chamber A formed by the cylinder tube 22' along the cylinder tube 22 'and the boss portion 16'. It is mounted slidably through. This brake piston 25 '
A piston body 26 'that slides between the cylinder tube 22' and the boss portion 16 'and a skirt portion 27' are integrally formed. The piston body 26 'causes the piston chamber A to be a spring chamber A1 and a brake release chamber A2. It is divided into and. In addition, a concave portion 28 'having a predetermined width is formed on the inner peripheral surface of the skirt portion 27'.
Is provided, and a brake actuating portion 29 'is interposed between the recess 28' and the split bush 24 '.

Reference numeral 30 'denotes a holding member of the brake operating portion 29', which is formed in a tubular shape so as to be slidably fitted on the outer periphery of the split bush 24 ', and the holding member 30' has
A plurality of rolling elements 32 'using steel balls are formed in a substantially annular shape in the drawing, and a plurality of rows (the case of three rows is illustrated in this embodiment) r1, r
2 and r3, the rolling element 32 'is divided into the split bushes 24.
A receiving hole 31 'is formed so as to be rollably accommodated while being in contact with the outer circumference of the'. In addition, the inner thickness of the holding member 30 'is equal to the receiving hole 3
When the rolling element 32 'is housed in 1', a part of the rolling element 32 'is formed to have a wall thickness protruding from the outer periphery of the holding member 30' by a predetermined height.

A spring 33 'is interposed between the holding member 30' and the piston body 26 'provided as described above, and the holding member 30' is attached in a direction opposite to the inner peripheral surface 36 'of the later-described expanding direction. It is energized. The urging force of the spring 33 ′ is due to the holding member 30.
′ Is slid in the anti-expansion direction so that the rolling element 32 ′ has an inner peripheral surface 36 ′.
The urging force is such that it can be brought into contact with. Further, a tubular elastic body 34 'made of, for example, synthetic rubber is fitted in the recess 28' formed on the inner peripheral surface of the skirt 27 ', and a plurality of rolling members are provided inside the recess 28'. Moving object 32
A plurality of (three in the present example) tilted rings 35 'are housed in the rows r1, r2, r3 of'.

The inclined ring 35 'is made of, for example, a steel material (which can be heat-treated) and has an outer diameter of a predetermined diameter, and an inner diameter of the brake opening chamber A as shown in the figure.
An inner peripheral surface 36 ′ having a substantially conical shape is formed on the second side so as to expand and incline at a predetermined angle. As will be described later, the angle of inclination of the inner peripheral surface 36 'is such that the static friction coefficient between the split bush 24' and the rolling element 32 'is a tangent value so that the contact state shifts from the large diameter side to the small diameter side. Formed below, also
A slit 37 'is provided in a part of the inclined ring 35' in the width direction so that its diameter can be increased or decreased. The brake piston 25 'having the brake actuating portion 29' thus mounted is slidably mounted by the brake spring 38 'and urged toward the brake release chamber A2.
The spring chamber A1 defined by ′ is vented to the atmosphere through an exhaust hole 39 ′ provided in the intermediate cover 6 ′, and the brake opening chamber A2 communicates with a brake opening port 40 ′ provided in the rod cover 14 ′. Has been done. As shown in FIG. 10, the brake release port 40 'is connected to the air supply source S via a flow path R branched immediately before the check valve B. Through this flow path R, the brake release chamber A
The air pressure is supplied to 2 by being branched from the air supply source S. A speed controller 902 in which a check valve 902a and an orifice (variable throttle valve) 902b are connected in parallel is provided in the middle of the flow path R.

Then, as shown in FIG. 10, a movable pulley 903 is rotatably supported by the tip of the piston rod 9'of the air cylinder 901 having the above-described structure, and is located below the intermediate stop mechanism portion 13 '. A fixed pulley 905 is rotatably supported by the shaft. The rope 11 is hung on both pulleys 903 and 905, one end of which is fixed to the air cylinder 901, and the lifted body W is fixed to its free end.

Next, the operation of the balancing apparatus of the present embodiment having the above structure will be described. At the time of normal operation, similarly to the first reference example , compressed air is supplied to the port 5'of the pneumatic cylinder portion 2 ', and the cylinder pressure adjusting chamber 8a' communicating with the port 5'is set as the lifted body W. By adjusting the pressure that opposes the acting gravity, the piston 8'is stopped and the lifted body W is stopped in a weightless state.

At this time, in the brake release chamber A2 of the intermediate stop mechanism portion 13 ', via the brake release port 40',
Compressed air from the air supply source S is constantly supplied. As a result, the brake piston 25 ′ is pushed toward the intermediate cover 6 ′ against the brake spring 38 ′ and stopped in the state of being in contact with the intermediate cover 6 ′.
The plurality of inclined rings 35 'fitted in the recesses 28' formed on the inner peripheral surface of the skirt portion 27 'of''are also moved integrally.
Further, the holding member 30 'is urged by the spring 33' and similarly abutted on the intermediate cover 6 ',
In this case, each rolling element 32 ′ is in contact with the inner peripheral surface 36 ′ of each inclined ring 35 ′ or in a state of being separated with a slight gap, and the slits of the brake metal 23 ′ and the split bush 24 ′. The widths of 23a 'and 24a' are also maintained in the normal state, and the piston rod 9'is slidable (that is, in the brake released state).

Therefore, in this brake released state, the worker himself / herself can lift and lower the lifting / lowering body to move the lifting / lowering body W up and down with a slight force as in the first reference example. it can. And
When the supply of air from the air supply source S is stopped for some reason, the air pressure in the cylinder pressure regulating chamber 8a 'of the pneumatic cylinder unit 2'decreases, and along with this, the brake release chamber A2. The air inside is also exhausted and the fluid pressure is released. Then, the piston rod 9 ′ is clamped by the operation described below, and the air cylinder 901 is
Becomes a brake state, and the lifted body W is prevented from falling.

When the fluid pressure in the brake release chamber A2 is released, the brake piston 25 'is moved to the brake release chamber A2 side by the brake spring 38', and the inclined ring 35 is moved.
´ is also moved integrally. This brake piston 25 '
The rolling element 32 'comes into contact with the inner peripheral surface 36' of the inclined ring 35 '. Since the inner peripheral surface 36 'abuts when the rolling element 32' is in a stationary state, the inner peripheral surface 36 'is equal to or less than the friction angle whose tangent value is the static friction coefficient between the split bush 24' and the rolling element 32 '. The rolling element 32 ′ rolls and moves from the larger diameter side of the inner peripheral surface 36 ′ to the smaller diameter side while rolling.

In this process, the axial horizontal component of the piston rod 9'and a large diameter due to the wedge effect are applied to the rolling element 32 'via the inner peripheral surface 36' according to the urging force of the brake spring 38 '. The vertical component of force acts in the direction. As a result of the action of this horizontal component force, the rolling element 32 ', as shown in FIG.
It rotates in the direction of arrow D and rolls on the split bush 24 '. Then, the holding member 30 ′ is brought into contact with the holding member 30 ′, and the holding member 30 ′ is slid in the axial direction of the piston rod 9 ′ against the biasing force of the spring 33 ′.

Further, the rolling direction of the rolling element 32 'is a direction in which the rolling element 32' moves in the small diameter direction with respect to the inner peripheral surface 36 ', and the rolling element 32' relatively moves in the small radial direction of the inner peripheral surface 36 '. Move to. As a result, the vertical component force acting on the rolling elements 32 'increases. The vertical component force acting on the rolling element 32 'presses the outer circumference of the split bush 24' in the radial direction.

Then, as the rolling element 32 'moves in the small diameter direction of the inner peripheral surface 36', the vertical component force increases, and the urging force of the brake spring 38 'and the rolling movement of the rolling element 32' in the small diameter direction are increased. When the position is balanced with the resistance, rolling of the rolling elements 32 'stops. The large vertical component force at this time presses the outer circumferences of the split bush 24 'and the brake metal 23' to reduce the widths of the slits 24a ', 23a', so that the piston rod 9'is fixed to the brake metal 23 '.
Clamped by. Therefore, the frictional resistance between the brake metal 23 'and the piston rod 9'at this time stops the movement of the piston rod 9'.

As described above in detail, in the balancing apparatus of this embodiment , even if the supply of compressed air from the air supply source S to the air cylinder 901 is stopped, it is supplied to the intermediate stop mechanism section 13 '. When the air pressure is released, the piston rod 9'is clamped and brought into a braking state, so that it is possible to reliably prevent the lifted body W from falling.

Further, in the present embodiment , the speed controller 902 is provided in the middle of the flow path R, and from the state where the air supply from the air supply source S is stopped, the cylinder pressure adjusting chamber 8a 'is supplied. When the air supply is started again, the compressed air does not flow through the check valve 902a and the orifice 902b
Only will flow. Therefore, the orifice 902b
As a result, the pressure rise in the brake release chamber A2 is delayed,
Since the brake release of the intermediate stop mechanism unit 13 'is delayed, it is possible to prevent the lifted body W from being accidentally dropped at the start of air supply. That is, since the intermediate stop mechanism portion 13 'in the present embodiment is configured so that the brake works at a relatively low supply pressure, the speed controller 9 is temporarily operated.
When there is no 02, the pressure in the brake release chamber A2 immediately rises at the start of air supply, and the brake is released while the pressure in the cylinder pressure regulating chamber 8a 'does not rise sufficiently, and the lifted body W falls. Will end up. Therefore, in the present embodiment, the speed controller 902 is provided to suppress the rate of pressure increase in the brake release chamber A2 and prevent the lifted body W from falling at the start of air supply.
When the supply of compressed air from the air supply source S is stopped, the air in the brake release chamber A2 will immediately escape through the check valve 902a of the speed controller 902, so the intermediate stop mechanism unit 13 ' The braking state is immediately established, and the lifted body W can be quickly prevented from falling.

The air cylinder 901 with the intermediate stop mechanism as described above is not limited to the balance device of the first reference example , but may be used as the cylinder of the balance device of the second to eighth reference examples. Of course.

Although the embodiments have been described above, the present invention is not limited to the above embodiments and can be implemented in various modes. For example, although the air cylinder is used in the above embodiments, the present invention is not limited to this, and another fluid cylinder (for example, a hydraulic cylinder or the like) can be used.

Examples of the cord-like body in the present invention include, but are not limited to, ropes made of synthetic resin, wires made of metal, and the like.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an overall configuration of a balancing device of a first reference example.

FIG. 2 is a cross-sectional view showing a pressure adjusting mechanism of a balance device of a second reference example.

FIG. 3 is a cross-sectional view showing a pressure adjusting mechanism of a balance device of a third reference example.

FIG. 4 is a cross-sectional view showing an air cylinder and a pulley mechanism of a balance device of a fourth reference example.

FIG. 5 is a cross-sectional view showing an air cylinder and a pulley mechanism of a balance device of a fifth reference example.

FIG. 6 is a cross-sectional view showing an air cylinder and a pulley mechanism of a balance device of a sixth reference example.

FIG. 7 is a sectional view showing an air cylinder and a pulley mechanism of a balance device of a seventh reference example.

FIG. 8 is a cross-sectional view showing a pressure adjusting mechanism of a balance device of an eighth reference example.

FIG. 9 is a cross-sectional view showing an air cylinder and a pulley mechanism of a balance device of an eighth reference example.

FIG. 10 is an explanatory diagram showing the overall configuration of the balance device of the present embodiment.

FIG. 11 is a cross-sectional view showing the air cylinder of the present embodiment.

12 is a sectional view taken along line EE of FIG.

FIG. 13 is an enlarged cross-sectional view of a brake operating portion of the air cylinder of this embodiment.

FIG. 14 is an explanatory diagram showing a conventional technique.

[Explanation of symbols] 1 ... Balance device 11 ... Rope 1
3 ... Movable pulley 15 ... Air cylinder 17 ... Main valve 1
9 ... Regulator valve 25 ... Piston 31 ... Piston rod 3
2 ... Constant pulley 901 ... Air cylinder with intermediate stop mechanism 2
′ ... Pneumatic cylinder section 13 ′ ... Intermediate stop mechanism section 2
3 '... Brake metal 29' ... Brake actuating part W
… Elevated body

Claims (2)

(57) [Claims] 1. A fluid cylinder having a pulley attached to the tip of a piston rod, a string-like body having a free end to which a lifted body is fixed and the other end fixed to a predetermined place, and the pulley to be the string-like body. In the suspension path of the object to be lifted by the body, it is incorporated so as to function as a moving pulley, and the cylinder chamber of the fluid cylinder is adjusted to a pressure that opposes the gravity of the object to be lifted and the piston is stopped. Branching from a pressure adjusting means and a fluid supply source for supplying fluid to the fluid cylinder
The fluid pressure is supplied to the
If the fluid pressure is released while the brake is released,
The piston rod is clamped and the brake is applied.
A rake means and a flow path connecting the brake means and the fluid pressure supply source
Supply from the fluid supply source towards the braking means
And a suppressing means for suppressing a rising speed of the fluid pressure . 2. A cylinder chamber of a fluid cylinder is lifted and lowered.
Adjust the pressure to oppose the gravity of the body and stop the piston
From the fluid supply source that supplies fluid to the fluid cylinder.
The fluid pressure is supplied to the
If the fluid pressure is released while the brake is released,
The piston rod will be clamped and it will be in a braking state
And a flow path connecting the brake means and the fluid pressure supply source.
Supply from the fluid supply source towards the braking means
And a suppression means for suppressing rate of increase of the fluid pressure to be
A balance device characterized in that