JPH02125102A - Fluid pressure driving actuator - Google Patents

Abstract

PURPOSE:To prevent the loss of driving rate, make the device suited for remote control, and obtain a large driving rate by connecting one end of an artificial muscle to a driven member through a driving transmission part, and providing the other end with an energizing member and an restricting member at contraction time of the energizing member driven independently by means of a controller. CONSTITUTION:A pulley 17 is driven by a wire 16 which connects each one end of a pair of artificial muscles 11, 12 arranged oppositely to each other, while rods 18, 19 which are connected to tension springs 21, 22 linked to an outer wall 20 are connected to each of the other ends of the artificial muscles 11, 12. Further, air chucks 23, 14 whose air cylinders are composed of pressurizer are arranged on the way of the rods 18, 19 so as to pressurizingly control the rods 18, 19. In a controller 27, pneumatic pressure from a compressor 28 is supplied to the artificial 11, 12 and the air chucks 23, 24 through a solenoid valve 30, for driving them. The loss of driving rate and sag are prevented, and thereby the device is suited for remote control while driving force thereof is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a fluid pressure driven actuator using a fluid pressure driven artificial muscle that can be contracted in the longitudinal direction by applying pressure.

[Conventional technology]

A fluid pressure driven actuator that converts the linear displacement of a flexible actuator that contracts due to the inflow of pressure fluid into rotational displacement is known, for example, from Japanese Patent Laid-Open No. 196410/1983. As shown in FIGS. 10(a) and 10(b), this connects a pair of flexible actuators 1.2 as artificial muscles that are contracted by the inflow of pressure fluid and one end side of these actuators 1.2. The actuator 1.2 is composed of a wire 3, a pulley 4 that converts the linear displacement of the wire 3 into rotational displacement, and a tension spring 5.6 connected to the other end of the actuator 1.2.

Further, a lock nut 7.8 is provided at the connection between the actuator], 2 and the tension spring 5.6, and the amount of movement of the lock nut 7.8 is regulated by a stopper 9.

Therefore, when pressure fluid is supplied to one of the actuators 1.2, for example, actuator 2, actuator 2 contracts in the longitudinal direction, and along with this contraction, wire 3 is pulled in the direction of arrow a and linearly displaced. The linear displacement of the wire 3 causes the bogie 4 to rotate in the same direction, and the linear displacement is converted into a rotational displacement. Next, when the pressure fluid is removed from the actuator 2 and the pressure fluid is supplied to the actuator 1, the actuator 2 expands in the longitudinal direction, and the actuator 1 contracts in the longitudinal direction. With this contraction, the wire 3 is pulled in the direction of the arrow and linearly displaced. wire 3
The linear displacement causes the pulley 4 to rotate in the same direction, and the linear displacement is converted into a rotational displacement. Therefore, by alternately supplying pressure fluid to the actuator 1.2, the pulley 4 can be rotated in forward and reverse directions, and if this pulley 4 is provided with a one-way clutch or the like, only forward rotation can be extracted as driving force. Moreover, according to the configuration, the actuator 1
．． Since the actuator 1.2 is constantly biased by the tension spring 5.6, even if the pressure of the pressurized fluid falls below the preset preset pressure, it can be absorbed by the contraction of the tension spring 5.6. 2, the wire 3, the pulley 4, etc. of the power transmission system can be maintained in a normal posture and arrangement.

However, as described above, when one actuator 2 contracts in the longitudinal direction, the tension spring 6 is pulled and the lock nut 8 comes into contact with the stopper 9. Therefore, the distance between the lock nut 8 and the stopper 9 is 0, and the pulley 4
The amount of rotation of the object in the direction of arrow a is lost by one shell. Therefore,
The lock nut 8 is brought into contact with the stopper 9 in advance so that the wire 3 moves only in the direction of the arrow a, thereby avoiding loss of drive amount.

[Invention or problem to be solved]

However, in the fluid pressure driven actuator configured as described above, in order to obtain a large drive amount, it is necessary to fix the lock nut to the stopper in advance to eliminate the action of the tension spring, and when contracting the other actuator, I had to loosen the lock nut that was tightened and then tighten the other lock nut. therefore,
Using a lock nut requires constant tightening and loosening of the lock nut, which is disadvantageous for remote operation;
In the end, lock nuts could not be used, and a large amount of drive could not be obtained in the past.

This invention was made in view of the above-mentioned circumstances, and its purpose is to provide a fluid pressure-driven actuator that can prevent loss of drive amount, is advantageous for remote control, and can obtain a large drive amount. It's about doing.

[Means and Actions for Solving the Problems] In order to achieve the above object, the present invention provides a plurality of fluid-pressure-driven artificial muscles on one end side, which are arranged in an antagonistic manner and can be contracted in the longitudinal direction by applying pressure. is connected by a drive transmission part, and this drive transmission part is connected to the driven part, while a biasing member for biasing the artificial muscle is connected to the other end side of the artificial muscle, and when the artificial muscle contracts. A restraint means for restraining the biasing member of the artificial muscle and a control means for independently driving the restraint means are provided.

When the artificial muscle contracts, the biasing member on the contracting side is restrained by the restraint means, all of the driving force of the artificial muscle is transmitted to the drive transmission section, and when the artificial muscle is extended, the biasing member is restrained. The reason is that it is made so that you can obtain biasing force by canceling it.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

1 to 5 show a first embodiment, and FIG. 1 shows the entire fluid pressure driven actuator. In FIG. 1, reference numerals 11 and 12 indicate a pair of fluid pressure-driven artificial muscles (hereinafter referred to as artificial muscles), which are arranged in parallel so as to compete with each other.

These artificial muscles 11 and 12 have the same structure, and as shown in FIG. It consists of a base 15.15. One end side of the artificial muscle 11, 12 configured in this way is connected by a wire 16 as a drive transmission section, and this wire 16 is wrapped around a pulley 17 as a driven section. Rods 18.19 are connected to the other ends of the artificial muscles 11.12, respectively, and the ends of these rods 18.19 are connected to tension springs 21.22 as biasing members connected to the outer wall 20. Ill.

Furthermore, air chucks 23 and 24 as restraining means are provided at the midpoints of the rods 18 and 19, respectively, to face each other. As shown in FIG. 3, these air chucks 23 and 24 are formed by a presser 26 that is moved forward and backward by a pair of air cylinders 25, and when moving forward, the presser 26 presses against the rod 18 and 19 to apply braking. is now possible.

Further, in FIG. 1, 27 is a control device, and 28 is a compressor for supplying air pressure as high-pressure fluid. This compressor 28 communicates with the base 15 of the artificial muscle 11.12 and the air cylinder 25 of the air chuck 23.24 via a solenoid valve 30 provided in a conduit 29. The compressor 28 is turned on and off by a switch 31, and the solenoid valve 30 is operated by a control signal from a controller 32 connected to the switch 31. Note that 33 is a pressure switch that communicates with the exhaust port 34 of the solenoid valve 30.

Next, the operation of the fluid pressure driven actuator configured as described above will be explained based on FIGS. 4 and 5.

When the artificial muscles 11.12 arranged in parallel in an antagonistic manner are to be contracted alternately, the switch 31 starts the compressor 28 and selects the artificial muscle 11.12 to be further contracted. As an example, a case will be described in which the command content of the controller 32 is set by the switch 31 so that the artificial muscle 11 is first contracted, and then the artificial muscle 12 is contracted, as shown in the time chart of FIG.

When there is no command from the controller 32, the air chucks 2B and 24 are in an open state as shown in FIG. 3, but as shown in FIG. When activated, air is supplied to the air chuck 23, the presser 26 is advanced by the air cylinder 25, the rod 18 is fixed, and the extension of the tension spring 21 is prevented.

With the tension spring 21 restrained in this way, as shown in FIG.
As shown in (b), the solenoid valve 3
0 is activated and air is supplied to the artificial muscle 11, the artificial muscle 11 contracts in the longitudinal direction. At this time, air chuck 2
Since 3 is closed and 24 is open, the wire 16 is pulled by the artificial muscle 11 in the direction of the arrow. Therefore, the unconstrained tension spring 22 is expanded, causing a linear displacement of the wire 16 and rotation of the pulley 17 in the direction of arrow a.

After supplying the amount of air set by the controller 32 to the artificial muscle 11 in this way, the controller 32 controls the solenoid valve 30.
, and the air in the artificial muscle 11 is passed through the exhaust port 3 of the solenoid valve 30.
Exhaust from 4. When the air in the artificial muscle 11 is expelled, the restoring force of the tension spring 22 returns the artificial muscle 12 to its original position.

At this time, the pressure switch 33 measures the exhaust pressure exhausted from the exhaust port 34, and when the exhaust pressure reaches "0", the pressure switch 33 manually sends a control signal to the controller 32. Next, the solenoid valve 30 is operated according to a command from the controller 32, and the air in the air chuck 23 is exhausted from the exhaust port 34.
Further, the solenoid valve 30 is actuated by a command from the controller 32 to supply air to the air chuck 24. Therefore, as shown in FIG. 5(C), the air chuck 24 is closed, fixing the rod 19 and restraining the tension spring 22. In this state, when the solenoid valve 30 is operated in response to a command from the controller 32 and air is supplied to the artificial muscle 12 as shown in FIG. 5(d), the artificial muscle 12 contracts in the longitudinal direction. At this time, since the air chuck 23 is open and the air chuck 24 is closed, the wire 16 is pulled by the artificial muscle 12 in the direction of the arrow. Therefore, the unrestrained tension spring 21 is expanded, and the wire 16 is linearly displaced, causing the pulley 17 to rotate in the direction indicated by the arrow.

After the amount of air set by the controller 32 is supplied to the artificial muscle 12 in this way, the controller 32 controls the solenoid valve 30.
When activated, the air in the artificial muscle 12 is exhausted from the exhaust port 34 of the solenoid valve 30. When the air in the artificial muscle 11 is expelled, the restoring force of the tension spring 21 returns the artificial muscle 11 to its original position.

Therefore, by repeating the above-described operation, the pulley 17 can be rotated in the forward and reverse directions, and if the pulley 17 is provided with a one-way clutch, it can also be rotated intermittently in one direction. Also, by changing the command of the controller 32, the time chart can be arbitrarily programmed and the pulley 17
can be controlled arbitrarily.

When the artificial muscle 11 or 12 contracts in this way, the corresponding tension spring 21.22 is moved to the air chuck 23.24.
A large drive amount can be obtained by restraining the tension springs 21, 22 so that they do not expand.

It should be noted that a method of connecting a current meter to the exhaust port 34 of the electromagnetic valve 30 as a device for detecting the elongation of the artificial muscle 11.12, and a method of connecting a current velocity meter to the exhaust port 34 of the electromagnetic valve 30, and a method of connecting the elastic cylindrical member 14 for regulation that constitutes the outer periphery of the artificial muscle 11.12 are possible. A method of measuring tension using a strain gauge, etc.
Furthermore, there is a method of measuring the amount of drive of the artificial muscles 11, 12 using an encoder or the like. Further, the pulley 17 may be provided with an angle detection device such as an encoder to perform position control.

Figures 6(a) and 6(b) show the second embodiment.
Components that are the same as those in the embodiment will be given the same reference numerals and their explanation will be omitted. In this embodiment, between the artificial muscle 11 and the tension spring 21 and between the artificial muscle 12 and the tension spring 22,
Rack insertion members 35 and 36 are provided between the two. These rack insertion members 35 and 36 are provided with engagement holes 35a and 36a that open in the vertical direction, respectively. Meanwhile, rack guides 37 and 38 are fixedly installed at the upper and lower parts of the rack insertion members 35 and 36,
These rack guides 37 and 38 support racks 39 and 40 whose tips can be freely engaged and disengaged from the engagement holes 35a and 36a so that they can move forward and backward.

Binions 41.42 are meshed with the racks 39.40, and these pinions 41.42 are pivotally supported on the rotating shaft of a motor 43.44. Binions 41.42 are rotated by the drive of the motors 43.44, and the racks 39.40 advance and retreat due to the rotation of the binions 41.42, and when the racks 39.40 move forward, the tip ends of the rack insertion members 35. 36 engagement holes 35a, 36a to restrain the tension springs 21, 22, and the engagement is released when retracting. And the motor 43.4
4 is connected to the controller 32 of the control device 27.

Therefore, the air chuck 23 in the first embodiment.
Motor 43.44 at the same timing as 24
When the motor 4 is activated, the controller 32 commands the motor 4.
3 is driven. The pinion 41 is driven by the motor 43.
rotates, the rack 39 moves forward, and the rack insertion member 35
It engages with the engagement hole 35a of. Next, the artificial muscle 11 is contracted according to a command from the controller 32. After the pressure switch 33 detects that the exhaust pressure becomes "0",
That is, after the artificial muscle 11 returns to its original position, the motor 43 is reversely rotated in accordance with a command from the controller 32. motor 4
3, the rack 39 retreats and comes out of the engagement hole 35a, and the other motor 44 rotates to rotate the pinion 42.

Therefore, the rack 40 moves forward and engages the engagement hole 36a, and then the artificial muscle 12 contracts.

By moving the racks 39 and 40 back and forth in this manner and engaging and disengaging them from the engagement holes 35a and 36a of the rack insertion members 35 and 36, the fixation is reliable and the strength is excellent.

FIG. 7 shows a third embodiment, in which the same components as those in the first embodiment are given the same numbers and their explanations will be omitted. In this embodiment, the first and second tension springs 21.2
2 is replaced by springs 45 and 46 made of shape memory alloy. These springs 45, 46 are connected to an energizing device 47 controlled by the controller 32, and can be restrained by selectively energizing the springs 45, 46.

Therefore, when the shape memory alloy springs 45 and 46 are energized at the same timing as the air chucks 23 and 24 in the first embodiment, the energizing device 47 is first applied to one of the springs 45 by a command from the controller 32. Turn on electricity. When the spring 45 is heated to a certain temperature or higher by energization, it maintains a pre-memorized shape, for example, a tightly wound state. Next, the artificial muscle 11 is contracted according to a command from the controller 32. At this time, the other spring 4
Since 6 is not energized, it has the property of being easily deformed by external force, and does not affect the contraction of the artificial muscle 11. After the pressure switch 33 detects that the exhaust pressure becomes "0", that is, the artificial muscle 11
After returning to the original position, the energizing device 47 stops energizing the spring 45 and energizes the spring 46 according to a command from the controller 32 . Next, the artificial muscle 12 is contracted as in the first embodiment.

By providing the springs 45 and 46 made of shape memory alloy in this manner, the structure is simple and the size can be reduced.

FIG. 8 shows a fourth embodiment, in which the actuator in the first embodiment is applied to an insertion section bending mechanism of an endoscope, and the same components as in the first embodiment are designated by the same numbers. The explanation will be omitted.

The endoscope 50 includes an operating section 51 and an insertion section 52, and the operating section 51 is provided with an actuator main body 53. A first rotating shaft 54 and a second rotating shaft 55 are coaxially supported on the actuator main body 53. and,
Small pulleys 5 are attached to the first and second rotating shafts 54 and 55, respectively.
6 and a large pulley 57 are fitted, and the first rotating shaft 54
The wire 13 of one artificial muscle 11 is connected to the small pulley 56 of the second rotating shaft 55, and the wire 13 of the other artificial muscle 12 is connected to the small pulley 56 of the second rotating shaft 55.

Further, one end of an angle wire 58.58 is connected to the large pulley 57 fitted on the first and second rotating shafts 54.55, and the other end of the angle wire 58.58 is connected to the tip of the insertion portion 52. It is connected to the component 59.

Therefore, as in the first embodiment, the small pulley 56 can be rotated by alternately contracting the artificial muscles 11 and 12, and the rotation of the small pulley 56 causes the large pulley 57 to rotate integrally. By pulling the angle wire 58, the distal end side of the insertion portion 52 can be bent.

Furthermore, operability is improved by providing the switch 31 of the control device 27 on the operating section 51 of the endoscope 50, and the stroke of the angle wire 58 is amplified by changing the diameter ratio of the small pulley 56 and the large pulley 57. It is also possible to increase the bending angle of the insertion portion 52.

By providing the actuator at the distal end of the insertion section 52 of the endoscope 50, it is possible to angle the long insertion section 52 from the operation section 51, which was conventionally impossible with an angle wire push/pull mechanism. .

FIG. 9 shows a fifth embodiment, in which the same components as those in the first embodiment are given the same numbers and their explanations will be omitted. This embodiment is composed of a first actuator 61 and a second actuator 62, and these first and second actuators 61, 62 are basically the same as in the first embodiment. The first actuator 61 has a first connecting rod 63
An air chuck 2 is provided on this first connecting rod 63.
3.24 and pulley 17 are supported.

Further, a connecting member 64 is provided on the pulley 17 of this first actuator 61, and this connecting member 64 has a second
The connecting rod 65 of the actuator 62 and the tension spring 2
1.22 are connected.

The connecting rod 65 is provided with an air chuck 23, 24 of the second actuator 62 and a pulley 17, and a manipulator 67 driven by a motor is attached to the pulley 17 via a connecting member 66.

With this configuration, the pulley 17 of the first actuator 61 is used as a joint to connect the second actuator 6.
The manipulator 67 can be rotated using the pulley 17 of the second actuator 62 as a joint, and an articulated robot can be constructed by connecting two or more sets of actuators.

〔Effect of the invention〕

As explained above, according to the present invention, when an artificial muscle is contracted, the biasing member side of the artificial muscle is restrained by the restraining means, thereby effectively preventing loss of drive amount and sagging of the artificial muscle. It is also advantageous for remote control and has the effect of being able to obtain a large amount of drive.

[Brief explanation of the drawing]

1 to 5 show a first embodiment of the present invention, in which FIG. 1 is a configuration diagram showing the entire fluid pressure driven actuator, and FIG. 2 is a partially cutaway side view of an artificial muscle. , Fig. 3 is a partially cutaway side view showing an enlarged air chuck, Fig. 4 is a time chart, Figs. 5 (a) to (d) are action explanatory diagrams, and Figs. is an overall configuration diagram of a fluid pressure driven actuator showing a second embodiment of the present invention;
Figure T57 is a configuration diagram showing the entire fluid pressure driven actuator according to the third embodiment of the present invention, and FIG. 8 is a configuration diagram showing the entire fluid pressure driven actuator according to the fourth embodiment of the invention. 9 is an overall configuration diagram of a fluid pressure driven actuator according to a fifth embodiment of the present invention, and FIGS. 10(a) and 10(b) are explanatory diagrams of a conventional pneumatically driven actuator. 11. 12... Fluid pressure driven artificial muscle, 16... Wire (drive transmission part), 17... Boo 9 (driven part),
...Tension spring (biasing member) 24...Air chuck (restraint means)

Claims (1)

[Claims] A plurality of fluid pressure-driven artificial muscles that are arranged to compete with each other and can be contracted in the longitudinal direction by applying pressure, a drive transmission section that connects one end side of these artificial muscles, and a driven section that is connected to this drive transmission section. , a biasing member connected to the other end side of the artificial muscle and biasing the artificial muscle, a restraining means restraining the biasing member of the artificial muscle when the artificial muscle contracts, and each of the restraining means What is claimed is: 1. A fluid pressure driven actuator characterized by comprising a control means for independently driving the actuator.