KR20030046499A - Air balance device - Google Patents

Abstract

It is easy to operate, and the air balance device which can balance with a to-be-carried body by a simple structure is obtained. The pressure adjusting valve 50 which adjusts the pressure of the supply-discharge channel | path 10 to the pressure taut against the weight of the to-be-transferred body 1 is provided. At the time of balance, the supply-discharge flow path 10 and the control flow path 18 are communicated, and at the time of a lift drive, the switching valve 14 which connects the supply-discharge flow path 10 and the pilot flow path 16 is provided. The cylinder 2 with which the to-be-carried body 1 was attached to the lever member 38 supported by the support point pin 44 is attached. A restoring force mechanism 48 for providing the lever member 38 with an acting force in the same direction as the load of the conveyed body 1 is provided near the support pin 44, and the load and restoring force of the conveyed body 1 are provided. The force force mechanism 74 which provides the lever member 38 with the action force balanced with the action force of the mechanism 48 is provided. In addition, the pressure regulating valve 50 supplies the supply / discharge channel 10 and the compressed air in accordance with the action force by the swing of the lever member 38 and the action force by the introduction of the pilot pressure from the control channel 18.

Description

Air balance device {AIR BALANCE DEVICE}

Conventionally, as disclosed in Japanese Unexamined Patent Application Publication No. 10 (1998) -30609, the load of the conveyed body is configured to act on the pressure chamber partitioned by the diaphragm, and the pressure fluctuation of the pressure chamber due to the change of the load Accordingly, the main valve is switched to supply compressed air to the working chamber of the cylinder from a pressure source, or open the working chamber to the atmosphere to control the pressure inside the working chamber to balance the load of the conveyed object and the working force of the cylinder. In accordance with this, it is known to be configured to suspend the carrier.

However, in such a conventional case, when lifting and lowering the conveyed body, the opening and closing of the male valve is not performed unless the volume of the working chamber is increased by overcoming the slide resistance of the packings of the cylinder and sliding the piston. There was a problem that operation was heavy and it was difficult to operate. In addition, the opening and closing of the main valve made by sensing the pressure change in the related art bleeds to prevent the occurrence of hysteresis (the difference in the resistance of the rising and falling at the time of balancing) and the opening and closing of the main valve By bleeding the two-position two-port valve, the effect of hysteresis was largely reduced), and there was a problem that the energy loss was large because air was constantly leaked. In addition, there has been a problem that a variety of valves have to be provided, which complicates the apparatus.

This invention relates to the air balance apparatus which hangs a to-be-carried body by facing the load of a to-be-carried body and supply pressure to a cylinder.

1 is a configuration diagram schematically showing an air balance device as an embodiment of the present invention;

2 is a configuration diagram schematically showing a main part of an air balance device as a second embodiment;

3 is a configuration diagram schematically showing a main part of an air balance device as a third embodiment;

4 is a configuration diagram schematically showing a main part of an air balance device as a fourth embodiment;

5 is a cross-sectional view of the pressure regulating valve of the present embodiment;

6 is a sectional view of a pressure regulating valve as another embodiment;

7 is a sectional view of a pressure regulating valve as another embodiment.

An object of the present invention is to provide an air balance device that is easy to operate and that can be balanced with a conveyed object with a simple configuration.

In order to achieve such a problem, the present invention has taken the following means to solve the problem. In other words,

And a pressure regulating valve for adjusting the pressure of the supply and discharge flow path connected to the working chamber of the cylinder for lifting and lowering the conveyed body to a pressure that tightly confronts the weight of the conveyed object, and the action force of the cylinder and the weight of the conveyed object. In the air balancer which balances

At the time of balancing, the supply and discharge flow path and the control flow path are communicated, and during the lifting and lowering operation, a switching valve is formed to communicate the supply and discharge flow path and the pilot flow path.

During the lifting and lowering operation, a lifting valve mechanism is provided for raising and lowering the conveyed object by supplying or discharging compressed air to the supply and discharge flow path through a variable throttle valve,

In addition, the cylinder is attached to a lever member that is swingably supported around the support pin.

Furthermore, a restoring force mechanism is provided near the support point pin that imparts an acting force to the lever member in the same direction as the load of the conveyed body by introduction of the pilot pressure from the control flow passage, Providing a force force mechanism for imparting a force acting on the lever member by introduction of compressed air from a tank in communication with the pilot flow path, which balances the action force of the restoring force mechanism,

The pressure regulating valve further supplies compressed air through the supply / discharge flow path, the control flow path and the switching valve in accordance with the action force caused by the swing of the lever member and the introduction force of the pilot pressure from the control flow path. It is an air balance apparatus made into.

The lift valve mechanism includes a lift valve for communicating a pressure source and the supply and discharge flow path through a variable throttle valve by introduction of a pilot pressure, and an air supply and supply and discharge flow path through the variable throttle valve by introduction of a pilot pressure. A descending valve for communicating may be provided. In addition, the biasing force mechanism may be provided with a biasing chamber communicated with the tank, and may apply an acting force to the lever member by the acting force of the compressed air pressure introduced into the biasing chamber.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail based on drawing.

As shown in FIG. 1, the code | symbol 1 is a to-be-carried body, and is suspended by the cylinder 2, and is supported. The piston 6 is slidably inserted into the cylinder tube 4 of the cylinder 2. When compressed air is supplied to the action chamber 8 formed by the cylinder tube 4 and the piston 6, it is comprised so that the action force which raises the piston 6 may act | act. Moreover, the hook 9 is attached to the rod 6a which is integral with the piston 6, and the to-be-carried body 1 can be suspended by this hook 9. As shown in FIG.

One end of the supply / discharge channel 10 is connected to the working chamber 8, and the auxiliary tank 12 is connected to the supply / discharge channel 10. The other end of the supply / discharge flow path 10 is connected to the switching valve 14. The switching valve 14 is a pilot operation type and balances the elevating drive position 14a for communicating the supply / discharge channel 10 and the pilot channel 16 with the supply / discharge channel 10 and the control channel 18. The position 14b is provided.

The high pressure oil passage 22 in communication with the pressure source 20 is connected to the supply / discharge oil passage 10, and the low pressure oil passage 24 opened in the air is connected. In the high pressure flow passage 22, a rising valve 26 and a variable throttle valve 28 are provided between the high pressure passages 22. The rising valve 26 has an open position 26a for communicating the high pressure flow passage 22 when the pilot pressure is introduced through the rising pilot flow passage 27 and a high pressure flow passage for evacuating the pilot pressure without introducing the pilot pressure. The closing position 26b which cuts off 22 is provided.

In the low pressure flow passage 24, a lowering valve 30 and a variable throttle valve 32 are provided therebetween. The lowering valve 30 has an open position 30a for communicating the low pressure passage 24 when the pilot pressure is introduced through the lowering pilot passage 31 and a low pressure passage for evacuating the pilot pressure without introducing the pilot pressure. The closed position 30b which interrupts | blocks 24 is provided. On the other hand, in this embodiment, the lifting valve 26, the variable throttle valve 28, the falling valve 30, and the variable throttle valve 32 comprise the lifting valve mechanism.

The rising pilot flow passage 27 and the falling pilot flow passage 31 are connected to the driving pilot flow passage 36 through the shuttle valve 34. The driving pilot oil passage 36 is connected to introduce a pilot pressure into the switching valve 14 so as to switch the switching valve 14 to the lifting driving position 14a. Moreover, the balance pilot flow path 37 which introduces the pilot pressure which switches the switching valve 14 to the balanced position 14b is also connected to the switching valve 14.

The cylinder tube 4 of the cylinder 2 is attached to one end of the lever member 38 so as to be able to swing through the pin 40 and to be adjustable in position. The lever member 38 is swingably attached to the suspension member 42 attached to the ceiling or the like through the support point pin 44.

The suspension body 42 is attached with a valve body 51 of the pressure regulating valve 50. The restoring force mechanism 48 is also integrally provided in the valve main body 51. The pressure regulating valve 50 includes an open position 50a for opening the control flow path 18 to the atmosphere, a cutoff position 50b for blocking the control flow path 18, and a control flow path 18. The communication position 50c which communicates with the high pressure flow path 49a connected to is provided. The high pressure flow path 49a is provided with a check valve 49b to prevent backflow.

Hereinafter, the specific structure of the pressure regulation valve 50 mentioned above is demonstrated by FIG. FIG. 1: is a case where the pressure regulating valve 50 is shown by JIS symbol, and FIG. 5 is sectional drawing which shows a specific structure.

The pressure adjusting chamber 52, the air supply chamber 54, and the exhaust chamber 56 are formed in the valve body 51 of the pressure regulating valve 50. The control flow path 18 is connected to the pressure adjustment chamber 52, and the high pressure flow path 49a is connected to the air supply chamber 54.

The pressure adjusting chamber 52 and the air supply chamber 54 communicate with each other, and the pressure adjusting chamber 52 and the air supply chamber 54 are configured to communicate with and shut off by the air supply valve body 58 slidably supported. In addition, the pressure adjusting chamber 52 communicates with the exhaust chamber 56 open to the atmosphere, and the pressure adjusting chamber 52 and the exhaust chamber 56 communicate with each other by the exhaust valve body 60 which is slidably supported. It is configured to be blocked.

The restoring force mechanism 48 is integrally provided in the valve main body 51, and the restoring force mechanism 48 is provided with the diaphragm 64 which partitions the accommodation hole 62 formed in the valve main body 51. As shown in FIG. The storage hole 62 is partitioned by the diaphragm 64, and the control chamber 66 is formed. The control chamber 66 communicates with the control flow passage 18 through the bypass flow passage 68.

A rod 70 is integrally attached to the diaphragm 64. The rod 70 penetrates through the valve body 51 and protrudes to the outside, and the tip thereof is in contact with the lever member 38. When the hydraulic pressure area of the diaphragm 64 is B and the pressure of the control chamber 66 is p, the action force of Bxp is comprised so that the lever member 38 may act on the position of the distance b from the support pin 44. . In addition, this acting force is comprised so that the acting force by the load of the to-be-carried body 1 may be acting around the support pin 44.

The stem 72 provided in the pressure regulating valve 50 passes through the exhaust valve body 60, and its tip is attached to the diaphragm 64. The rear end of the rod 70 is in contact with the action of the pilot pressure introduced into the control chamber 66. When the rod 70 presses the lever member 38, the rod 70 slides the exhaust valve body 60 through the stem 72 to the open position 50a for communicating the pressure adjusting chamber 52 and the exhaust chamber 56. Configured to switch. In addition, when the rod 70 is pressed by the lever member 38, the communication position which slides the air supply valve body 58 through the stem 72, and communicates the pressure regulation chamber 52 and the air supply chamber 54. It is configured to switch to 50c.

A suspension force mechanism 74 is attached to the suspension member 42 so as to face the restoring force mechanism 48. The biasing force mechanism 74 has a diaphragm 80 which partitions the storage hole 78 formed in the main body 76, and the biasing chamber 82 is provided in one side of the storage hole 78 partitioned by the diaphragm 80. As shown in FIG. Is formed. A rod 84 is integrally attached to the diaphragm 80, the rod 84 penetrates through the main body 76, and the tip thereof is in contact with the lever member 38. In this embodiment, the actuator is comprised by these.

The main body 76 is provided with an introduction port 86 in communication with the gas chamber 82, and one end of the introduction flow path 88 is connected to the introduction port 86. A tank 90 is connected to the other end of the introduction flow path 88, and a check valve 92 and a throttle 94 are provided in parallel between the introduction flow path 88. In addition, the pilot flow path 16 is connected to the introduction flow path 88 on the tank 90 side rather than the check valve 92.

When the hydraulic pressure area of the diaphragm 80 is C and the pressure of the gas chamber 82 is p, the acting force of Cxp is configured to act on the lever member 38 at the position of the distance c from the support pin 44. have. Moreover, this acting force is comprised so that it may act in the opposite direction to the acting force by the load of the to-be-carried body 1 around the support point pin 44.

The distance between the pin 40 and the support pin 44 is a, the hydraulic pressure area of the working chamber 8 is A, the pressure of the working chamber 8 is p, the load or the hook 9 of the conveyed body 1, If the total weight of the lifting object, such as the rod 6a, the piston 6, and the like, is W, when the pressures of the working chamber 8, the control chamber 66, and the biasing chamber 82 are the same, the following equation is formed. do. On the other hand, the spring (between the suspension member 42 and the lever member 38) is balanced between the downwardly weight (weight of the cylinder tube 4 or the like) applied to the pins 40 other than the lifting object. 96) are arranged.

aA + bB = cC... (One)

W = pA… (2)

a ＞ b

Hereinafter, the operation of the air balancer described above will be described.

First, as shown in FIG. 1, the to-be-transported body 9 is suspended by the hook 9. As shown in FIG. At the time of the lift driving, the pilot pressure is supplied to the rising pilot flow passage 27. Therefore, the rise valve 26 is switched to the open position 26a so that the compressed air is driven from the pressure source 20 by the variable throttle valve 28, the rise valve 26, the high pressure flow passage 22, and the exhaust flow passage 10. Through the working chamber (8). By the action of the compressed air pressure supplied to the working chamber 8, the to-be-carried body 1 raises through the piston 6 and the rod 6a. At that time, the conveyed object 1 rises at the speed according to the setting of the variable throttle valve 28.

In addition, the pilot pressure is introduced into the switching valve 14 through the shuttle valve 34 and the driving pilot flow passage 36 by the supply of the pilot fluid to the upward pilot flow passage 27, thereby switching the valve 14. Is switched to the lift drive position 14a. Accordingly, compressed air is supplied to the tank 90 through the supply / discharge channel 10, the switching valve 14, and the pilot channel 16, and compressed air is supplied to the gas chamber 82 through the throttle 94. .

After raising the to-be-transferred body 1 to predetermined height, when supply of the pilot fluid to the upward pilot flow path 27 is stopped and exhausted, the lift valve 26 will switch to the closed position 26b. Therefore, the high pressure flow path 22 is interrupted | blocked, and the working force by the pressure p in the working chamber 8 balances the load of the to-be-carried body 1 (formula (2) is established). In addition, a closed circuit is formed by the working chamber 8, the supply / discharge channel 10, the pilot channel 16, the introduction channel 88, the tank 90, and the gas chamber 82, and the pressures p thereof. Becomes the same.

On the other hand, when the pilot pressure is supplied to the descending pilot oil passage 31 during the lift driving, the lowering valve 30 is switched to the open position 30a. Accordingly, the compressed air in the working chamber 8 is discharged into the atmosphere through the supply / discharge channel 10, the lower valve 30, the variable throttle valve 32, and the low pressure channel 24, so that the conveyed object 1 is lowered. do. At that time, the conveyed object 1 descends at the speed according to the setting of the variable throttle valve 32.

In addition, by supplying the pilot fluid to the descending pilot flow passage 31, the pilot pressure is introduced into the switching valve 14 through the shuttle valve 34 and the driving pilot flow passage 36, thereby switching the valve 14. Is switched to the lift drive position 14a. Therefore, compressed air is also supplied from the tank 90 through the pilot flow path 16, the switching valve 14, the supply / discharge flow path 10, the low pressure flow path 24, the lowering valve 30, and the variable throttle valve 32. Is released during.

After the conveyance body 1 is lowered to a predetermined height, when the supply of the pilot fluid to the descending pilot flow passage 31 is stopped and exhausted, the lowering valve 30 is switched to the closed position 30b. Therefore, the low pressure flow path 24 is interrupted | blocked, and the action force by the pressure p in the working chamber 8 balances the load of the to-be-carried body 1 (formula (2) is established). In addition, a closed circuit is formed by the closing circuit 82 by the working chamber 8, the supply / discharge channel 10, the pilot channel 16, the introduction channel 88, the tank 90, and the gas chamber 82. These pressures p become equal.

The lever member 38 acts on the periphery of the support pin 44 at the same time as the action force according to the load of the conveyed object 1 and the action force of the restoring force mechanism 48, and a force force mechanism 74 opposed thereto. ) Action of the action. When the lever member 38 swings, the pressure regulating valve 50 is switched, and when the pressure in the control chamber 66 is equal to the pressure in the working chamber 8, the above-described equation (1) holds and the lever member ( The acting force around the support pin 44 of 38 is balanced.

The balance pilot flow path 37 is provided to the switching valve 14 when the conveyance body 1 is not raised and lowered by using the compressed air pressure, but the operator raises or lowers the conveyance body 1 or the like directly. Supply pilot pressure through). Therefore, the switching valve 14 is switched to the balance position 14b so that the control flow path 18 and the supply / discharge flow path 10 communicate with each other. However, at this time, if there is a difference between the pressure of the control flow passage 18 and the pressure of the pilot flow passage 16, a malfunction (rising or falling) occurs. At this time, the position of the pin 40 may be changed by moving along a long hole, or the attachment position b of the pressure regulating valve 50 may be changed, and the above formula (1) may be established.

At the time of this balance, when raising the to-be-carried body 1, the to-be-carried body 1, the cylinder 2, etc. are lifted. As a result, the lever member 38 swings around the support pin 44 so that the pressure regulating valve 50 is switched to the communication position 50c via the rod 70. From the pressure source 20, compressed air is supplied to the working chamber 8 through the high pressure flow path 49a, the pressure regulating valve 50, the control flow path 18, and the supply-discharge flow path 10, and the working chamber 8 is carried out. Increases, and the conveyed object 1 rises. At the same time, compressed air is also supplied to the control chamber 66 through the control flow path 18 and the bypass flow path 68, and the pressure rises. When lifting the to-be-carried body 1 etc., it is necessary to lift up against the action force of the restoring force mechanism 48, but can be lifted by the light force of b / a by the lever member 38. As shown in FIG.

When the lifting stops, the lever member 38 swings around the support pin 44 through the rod 70 under the action of the supply pressure p introduced into the control chamber 66. At that time, the pressure regulating valve 50 is switched to the open position 50a so that the compressed air is discharged from the control chamber 66 into the atmosphere.

Therefore, the pressure in the control chamber 66 falls. And when the above-mentioned formula (1) becomes the pressure p which holds, the swing of the lever member 38 will stop, the pressure regulating valve 50 will switch to the cutoff position 50b, and also the action chamber 8 The working force by the pressure p in the inner circle and the load of the conveyed body 1 are balanced, and the ascent is stopped.

On the other hand, when the conveyance body 1, the cylinder 2, etc. are lowered, the lever member 39 swings around the support pin 44 and, by the action of the pressure in the control chamber 66, the pressure regulating valve 50 ) Is switched to the open position 50a, and the compressed air in the working chamber 8 is discharged into the atmosphere through the supply / discharge channel 10, the switching valve 14, the control channel 18, and the pressure regulating valve 50. Then, the conveyed object 1 descends.

When it stops lowering, the lever member 38 swings around the support pin 44 through the rod 84 under the action of the pressure p introduced into the biasing chamber 82 of the biasing mechanism 74. do. At that time, the pressure regulating valve 50 is switched to the cutoff position 50b via the rod 70. Then, the above formula (1) holds, and the swing of the lever member 38 stops, and the total weight such as the action force by the pressure p in the working chamber 8 and the load of the object 1 to be transferred ( W) is balanced, stopping the descent.

By providing the tank 90, when raising and lowering the conveyed body 1 by hand, the pressure change in the biasing chamber 82 of the biasing force mechanism 74 can be made small, and the lever member 38 can be lightly swinged. It is. Moreover, when the check valve 49b is provided in the high pressure flow path 49a, and supply of compressed air from the pressure source 20 stops, the pressure in the control chamber 66 of the pressure regulating valve 50 will fall. It is switched to the communication position 50c side, and the to-be-carried object 1 is prevented from falling by self weight. Furthermore, by providing the auxiliary tank 12 and the throttle 94, it is possible to prevent the occurrence of chatter operation.

Hereinafter, the air balance apparatus of 2nd Embodiment different from embodiment mentioned above is demonstrated by FIG. In addition, about the member same as the air balance apparatus of embodiment mentioned above, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted. The same applies to the following.

In the second embodiment, the cylinder tube 102 of the cylinder 100 is fixed horizontally, and the fixed pulley 104 of the cylinder tube 102 is rotatably supported. A moving pulley 110 is rotatably supported on the rod 108 integral with the piston 106, and a wire 112 for suspending the conveyed body 1 is connected to the fixed pulley 104 and the moving pulley 110. After being placed, the tip of the wire 112 is fastened to the pin 40.

By moving the compressed air through the supply-discharge channel 10 between the working chamber 114 of the cylinder 100, the moving pulley 110 moves, and elevates the conveyed object 10 with twice the action force. You can. Therefore, as shown in the following formulas (1a) and (2a), the hydraulic pressure area of the working chamber 8 is twice the hydraulic pressure area A of the above-described embodiment, so as to balance the conveyed object 1. Can be.

Also in the case of the second embodiment, similarly to the above-described embodiment, by lifting or lowering the transported object 1, the transported object 1 can be lifted with a light force and the transported object ( You can also keep 1) in a balanced state.

(A / 2) x a + b x B = c x C... (1a)

p x A / 2 = W... (2a)

a ＞ b

In addition, as in the third embodiment shown in FIG. 3, the speed increasing mechanism 120 may be provided. The transfer mechanism 1 is attached to the hook 128 attached to the tip of the wire 126 by winding the wire 126 on the drum 124 using the screw mechanism 122. I will. In addition, the cylinder tube 4 is attached to the frame 230 supported by the lever member 38, and the rod 6a is attached to the drum 124 via the thrust bearing 134. Here, if L is a screw lead and D is a drum pitch diameter, the following equation holds. When the speed increasing mechanism 120 is used, speed is increased by driving the cylinder 2.

(L / πD) x A x a + b x B = cC... (1b)

(p × L × A) / (π × D) = W... (2b)

a ＞ b

In addition, as in the fourth embodiment shown in FIG. 4, the object to be conveyed 1 may be hung on the lever 142 that is swingably supported around the pin 140. At that time, the tip of the rod 6a of the cylinder 2 is connected to this lever 142. Here, when E is the distance from the pin 140 to the to-be-transferred body 1, and e is a distance from the pin 140 to the rod 6a, the following formula is satisfied. Therefore, even if the cylinder 2 is pressed, it can balance with the to-be-carried body 1.

(e / E) x A x a + b x B = c x C. (1c)

(e / E) x p x A = W. (2c)

a ＞ b

Hereinafter, the pressure control valve 150 of another embodiment is demonstrated with FIG.

In the pressure regulating valve 150, the valve body 152 is slidably supported by the valve body 151. The valve body 152 is comprised so that the high pressure flow path 49a and the control flow path 18 may be interrupted | blocked and communicated with the seat and the space | separation with respect to the valve seat 154 formed in the valve main body 151. As shown in FIG. The valve body 152 is biased in the direction seated on the valve seat 154 by the coil spring 156.

A storage hole 158 is formed in the valve body 151, and the storage hole 158 is partitioned off by the diaphragm 160, and a control chamber 162 is formed on one side. The front end of the valve body 152 protrudes in the control chamber 162, and the rear end of the valve body 152 protrudes to the outside of the valve body 151.

The exhaust hole 164 penetrates and is formed in the valve body 152 in the axial direction, and the exhaust hole 164 is formed so that the control chamber 162 can communicate with the atmosphere. The diaphragm 160 is in contact with the tip of the valve body 152, and is comprised so that the exhaust hole 164 may be closed or opened. Moreover, the hydraulic pressure area of the diaphragm 160 in the control chamber 162 is formed so that B may become. The pressure adjustment chamber 168 is connected to the control flow path 18, and the control chamber 162 is connected to the control flow path 18 through the bypass path 170.

Also in the case of the pressure regulating valve 150 of this embodiment, when the rod 70 is pressed by the lever member 38, the valve body 152 is slid to be spaced apart from the valve seat 154 and the high pressure flow path 49a is provided. ) And the control flow path 18 are switched to the communication position 50c (refer FIG. 1) which connects through the pressure adjustment chamber 168. FIG. When the pilot pressure introduced into the control chamber 162 rises, the diaphragm 160 is separated from the front end of the valve body 152, and the control flow path 18 is passed through the bypass path 170 and the control chamber 162. A switch is made to the open position 50a (see FIG. 1) in communication with the exhaust hole 164.

Hereinafter, the pressure regulating valve 180 of another embodiment is demonstrated by FIG.

The spool 182 is slidably supported by the valve body 181 of the pressure regulating valve 180, and the communication between the control flow path 18 and the high pressure flow path 49a and the shutoff are performed by the slide of the spool 182. And the communication between the control flow path 18 and the atmosphere and the cutoff are configured.

Moreover, the control chamber 184 is formed in the end of the spool 182, and is comprised so that the acting force which slides the spool 182 may act by the action of the pilot pressure introduce | transduced into the control chamber 184. The control room 184 is formed so that a hydraulic pressure area may become B. The control room 184 is connected to the control flow path 18 through the bypass path 192.

Coil springs 188 and 190 are disposed on both end sides of the spool 182, and the coil springs 188 and 190 are formed so that the spool 182 is in the cutoff position 50b (see FIG. 1). 182) is added from both sides. In addition, what is necessary is just to install these coil springs 108 and 110 as needed, and it is not necessary to necessarily provide them.

The rod 70 is slidably inserted into the valve main body 181 on the opposite side to the control chamber 184. When the rod 70 is pushed in, the spool 182 is slid. Thereby, it switches to the communication position 50c (refer FIG. 1) which communicates the control flow path 18 and the high pressure flow path 49a. The opening position 50a (see FIG. 1) for sliding the spool 182 to open the control flow passage 18 in the atmosphere by the action of the pilot pressure from the control flow passage 18 introduced into the control chamber 184. It is configured to switch to).

As mentioned above, this invention is not limited to these embodiments at all, It can implement in various forms within the range which does not deviate from the summary of this invention.

As described in detail above, the air balance device of the present invention can balance the conveyed material with a small number of parts, and at the same time, by switching the pressure regulating valve with light force by the lever member, the energy due to air leakage due to the bleed Since there is no loss and the influence of the slide resistance of the packings of a cylinder is small, the operation to raise and lower the to-be-carried body can be performed with a small force, and it is easy to operate.

Claims (3)

And a pressure regulating valve for adjusting the pressure of the supply and discharge flow path connected to the working chamber of the cylinder for lifting and lowering the conveyed body to a pressure that tightly confronts the weight of the conveyed body, and the action force of the cylinder and the weight of the conveyed object are provided. In the balancing air balance device, At the time of balancing, the supply and discharge flow path and the control flow path are communicated, and during the lifting and lowering operation, a switching valve is formed to communicate the supply and discharge flow path and the pilot flow path. During the lifting and lowering operation, a lifting valve mechanism is provided for raising and lowering the conveyed object by supplying or discharging compressed air to the supply and discharge flow path through a variable throttle valve, Attaching the cylinder to a lever member that is swingably supported around a support pin; By introducing a pilot pressure from the control flow path, a restoring force mechanism is provided near a support point pin that imparts an acting force to the lever member in the same direction as the load of the conveyed member, and at the same time, the load and the restoring force of the conveyed member. A biasing mechanism is provided which imparts to the lever member the introduction of compressed air from a tank in communication with the pilot flow path to balance the operating force of the mechanism; The pressure regulating valve is configured to rapidly deliver compressed air through the supply and discharge flow path, the control flow path and the switching valve in accordance with the action force by the swing of the lever member and the introduction force by the introduction of the pilot pressure from the control flow path. Air balance device. The lift valve mechanism according to claim 1, wherein the elevating valve mechanism includes an elevating valve that communicates a pressure source and the supply and discharge flow path through the variable throttle valve by introduction of a pilot pressure, and an atmospheric pressure and the supply and discharge by introducing a pilot pressure. And a descending valve for communicating a flow path through the variable throttle valve. The force application mechanism according to claim 1 or 2, wherein the force mechanism includes a tax chamber communicated with the tank, and imparts an acting force to the lever member by an action force of compressed air pressure introduced into the tank. Air balance device.