JPWO2020158352A1 - Servo valve unit and equipment - Google Patents

Abstract

A unit body (10) having a first end portion (61a) and a second end portion (61b), a first valve portion (20R), a second valve portion (20L), and a first valve portion (20R). The first seal member (22) that opens and closes, the second seal member (22) that opens and closes the second valve portion (20L), and the first seal member (22) that drives the first seal member (22) by the first electric pulse (S1). A drive mechanism, a second drive mechanism for driving the second seal member (22) by a second electric pulse (S2), and a supply extending between the first end portion (61a) and the first valve portion (20R). The flow path (12), the exhaust flow path (13) extending between the second end (61b) and the second valve (20L), the first valve (20R) and the second valve (20L). ), A common flow path (11) connected to the supply flow path (12) and the exhaust flow path (13), and a drive flow path (14) connected to the pneumatic actuator (40). (20).

Description

The present invention relates to a servo valve unit, and more particularly to a servo valve unit for driving a pneumatic cylinder used for a humanoid robot or the like and a device using the same.

Many large companies and talented researchers have been researching robots for at least 50 years, but practical humanoid robots that can actually work in place of humans at disaster sites, nursing care sites, homes, etc. Has not yet been realized.

[Conditions for realizing a humanoid robot]
In order to realize a humanoid robot, it is necessary to design a large number of actuators and related parts according to the number of joints with the same weight as humans, and to accommodate them in the same volume as humans. Each actuator is required to have strong power according to the work.

[Actuator method]
There are three types of actuators: electric, hydraulic, and pneumatic, but for the reasons described below, no actuator that satisfies the above conditions has been realized.

[Electric servo motor control technology]
It is the most advanced control technology and is widely used in industry. Many researchers are developing humanoid robots that use electric servomotors, and robots that perform like humans have also been developed by making full use of AI and the like. On the other hand, since the motor and reducer are very heavy, the power per actuator unit volume is small. If you try to increase the power, the actuator will become larger and heavier, and the effect will be offset. When a large current is passed through a small actuator to generate power, the amount of heat generated increases and damage occurs. To prevent this, cooling is required, which eventually increases the weight and volume. Considering only the problems of weight and volume, it is impossible to realize a humanoid robot that makes heavy use of electric servomotors. In addition, a servo amplifier is required for operation control, torque detection and protection circuits are required to prevent damage when overload and reaction force are applied, and there is a problem that the structure becomes complicated and expensive. ..

[Flood servo servo control technology]
It is widely used in the industrial world as well as electric servo motor control technology, and is an indispensable technology for machine tools and industrial machines. The biggest advantage is the large power per actuator unit volume. There are abundant control devices, and hydraulic servo technology is also highly evolving. On the other hand, from the viewpoint of application to humanoid robots, the biggest drawback is that a hydraulic source must be installed. Since the hydraulic source is driven by a motor or engine, the weight and volume are extremely large. You also need a servo amplifier. Therefore, it is very difficult to realize a humanoid robot by a hydraulic drive system. In addition, flood control has poor compressibility, and there is a risk of damaging surrounding objects and people due to overload, and there is a possibility of polluting the surroundings due to oil leakage, making it difficult to use for interpersonal purposes.

[Pneumatic servo control technology]
Pneumatic cylinders (pneumatic actuators) can be made lighter because aluminum can be used for the main parts, and have the advantage of having a large power per unit volume, and are widely used as drive sources in various fields. However, servo control of pneumatic cylinders is a very difficult technique. The purpose of the servo is to control the piston position and / or speed, but since the drive of the pneumatic cylinder basically involves compressibility and friction, accurate control is difficult compared to the electric or hydraulic system.

FIG. 11 shows a block diagram of the conventional pneumatic servo control. This block diagram is basically the same for the electric servo and the hydraulic servo. Here, the output signal of the position sensor may be digital or analog. Usually, the command signal will be a digital signal.

The pneumatic servo amplifier generally detects the difference between the command signal and the position sensor information, and controls the pneumatic servo valve based on digital arithmetic processing such as PID, which is the optimum control. However, currently available pneumatic servo valves are limited to analog systems. The pneumatic servo valves currently available are mainly spool type servo valves (Patent Document 1) and flapper type servo valves (Patent Document 2), both of which are analog type.

FIG. 12 is a spool type servo valve of Patent Document 1, which includes a sleeve 16 having a supply flow path 40, an exhaust port 42, and a load flow path 44, and a spool 14 having three land portions 20, 22, and 24, and is a solenoid. The spool 14 is driven in the X direction by the linear motor 50 of the formula. When the land 22 is moved in the + X direction from the state where it matches the load flow path 44, air Pa is supplied from the pneumatic source Ps to the pneumatic cylinder (not shown), and when it is moved in the −X direction, air is supplied from the pneumatic cylinder. Is exhausted, and when the land 22 is aligned with the load flow path 44, the supply and exhaust stops. The position or speed of the pneumatic cylinder is adjusted by the opening degree of the load flow path 44 due to the movement of the land 22.

FIG. 13 is a flapper type servo valve of Patent Document 2, in which the exhaust port 32 is opened and closed by the movement of the flapper 22 in the X direction by the solenoid type linear motor 14, and the back pressure is reduced according to the opening degree of the exhaust port 32. The position of the movable body 6 is controlled by supplying Pa to the pneumatic cylinder 2.

Each servo valve is an analog system in which the valve opening degree is adjusted by controlling the spool 14 or the flapper 22 by a solenoid, and a servo amplifier is indispensable. In addition, since the valve opening must be controlled precisely, extremely advanced processing technology and control technology are required. Further, since each servo valve needs to be operated while bleeding air in order to reduce friction and the like, the amount of compressed air used becomes enormous as the number of servo valves increases. It seems that these are the reasons why pneumatic cylinders have hardly been studied so far in fields such as humanoid robots where position control is required with a certain degree of accuracy.

The above-mentioned drawbacks of electric servos and hydraulic servos are fundamental and inevitable in principle no matter how hard you try. Humanoid robots that use electric servo control will continue to be studied due to the ease of precision control, etc., but the present invention states that even with a huge budget and a large number of human resources, it is impossible to realize them. Is thinking. In the case of an electric servo, it is first converted into a magnetic force by the action of a coil, and then the motor is rotated by the magnetic force and the repulsion of the magnetic force. At this time, the flowing current value itself is the source of output power. When an electric current flows, heat is generated and a part of it becomes thermal energy, and the rotational energy rotated at a higher speed is decelerated again. Therefore, the more the deceleration is performed in an attempt to exert force, the more the energy efficiency drops at an accelerating rate. The more power is reduced by heat generation and the more decelerated, the less energy can be used.

If a high-power actuator that can be called an artificial muscle is developed, I think there will be new developments. Since human muscles are actually present, it should soon be possible to artificially create equivalents. However, in the present situation where such an actuator does not exist, the present inventor considers that the pneumatic servo control method is the only option for realizing a humanoid robot.

Compressed air is created by rotating a compressor for a certain period of time with an electric motor. At this time, there is no limit to the size and power upper limit of the electric motor and compressor. In other words, compressed air is high-density energy itself and acts directly on the drive of the cylinder. Therefore, it is possible to generate the power required for the humanoid robot without increasing the volume and weight. The drawbacks of the pneumatic method are as described above, but none of them are fundamental. Compressibility is unavoidable in pneumatic servos, but cylinder friction can be reduced to the limit depending on the design. In addition, humanoid robots do not require accurate control like machine tools and industrial machines. This is because humans do not make such precise movements at all. In the conventional pneumatic servo valve, a servo amplifier and extremely advanced processing technology are required because the pneumatic control method is an analog method.

JP-A-2007-187296 Japanese Unexamined Patent Publication No. 2006-057719

Based on the above considerations, the present inventor has made diligent development to realize a servo valve unit that solves all the drawbacks of the above-mentioned pneumatic servo control technology, or at least the serious drawbacks, and completes the present invention. I arrived.

The present invention provides a servo valve unit capable of controlling the position of a pneumatic cylinder without using a servo amplifier, and / or relaxing the requirement for machining accuracy, and / or not requiring air bleeding. It is an object of the present invention to provide a compact and lightweight servo valve unit capable of driving a pneumatic cylinder with a large power. By achieving these objectives, the conditions described in the above [Conditions for realizing a humanoid robot] can be achieved.

In this application,
A servo valve unit for driving a pneumatic actuator.
A unit body having a first end and a second end,
1st valve and
2nd valve and
A first seal member that opens and closes the first valve portion, and
A second seal member that opens and closes the second valve portion, and
A first drive mechanism that drives the first seal member by a first electric pulse,
A second drive mechanism that drives the second seal member by a second electric pulse,
A supply flow path extending between the first end portion and the first valve portion,
An exhaust flow path extending between the second end and the second valve,
A common flow path connected to the supply flow path and the exhaust flow path via the first valve portion and the second valve portion, and
It has a drive flow path connected to the pneumatic actuator and has
The first drive mechanism and the second drive mechanism are arranged in a drive mechanism arrangement portion located between the first end portion and the second end portion.
The drive flow path is
A branch portion located between the drive mechanism arrangement portion and the first end portion branches from the common flow path and extends to the first end portion, or
A servo valve unit that branches from the common flow path at a branch portion located between the drive mechanism arrangement portion and the second end portion and extends to the second end portion is disclosed.

In a preferred embodiment, the branch portion is located between the drive mechanism arrangement portion and the first end portion, and the supply flow path and the drive flow path are axially oriented at the first end portion of the unit body. It is postponed.

In addition to this application
It is a unit body composed of multiple body parts arranged in the axial direction.
1st valve,
2nd valve,
A first seal member that opens and closes the first valve portion,
A second seal member that opens and closes the second valve portion,
A first drive mechanism that drives the first seal member in the axial direction by a first electric pulse,
A second drive mechanism that drives the second seal member in the axial direction by a second electric pulse,
A supply flow path extending in the axial direction between one end of the unit body and the first valve portion,
An exhaust flow path extending in the axial direction between the other end of the unit body and the second valve portion,
A common flow path connected to the supply flow path and the exhaust flow path via the first valve portion and the second valve portion, and
The unit body having a drive flow path connected to the pneumatic actuator and
A servo valve unit for driving a pneumatic actuator, which has a fastener for tightening the plurality of body parts in the axial direction, is disclosed.

In a preferred embodiment, in each of the inventions, the two unit bodies are opposed to each other.
The supply flow paths of the two unit bodies are connected to each other, and the supply flow paths and the two drive flow paths of the two unit bodies are drawn out from the side surfaces of the unit body.

In a preferred embodiment, in each of the above inventions, the frequencies of the first electric pulse and the second electric pulse are 100 Hz or more.

In a preferred embodiment, in each of the above inventions, the first drive mechanism and the second drive mechanism have a solenoid, and the solenoids of the first drive mechanism and the second drive mechanism are arranged adjacent to each other with a single magnetic plate portion interposed therebetween. Has been done.

The present application further discloses a device having the servo valve unit according to any one of the above, the pneumatic actuator, and a movable member operated by the pneumatic actuator.

In the above invention, the position of the pneumatic cylinder can be controlled without using a servo amplifier, and / or the requirement for machining accuracy is relaxed, and / or air bleeding is unnecessary, and / or. A servo valve unit capable of driving a pneumatic cylinder with a large power can be realized, and further, a remarkable reduction in size and / or an improvement in durability performance of the servo valve unit can be achieved.

FIG. 1 shows a servo valve unit 2 according to an embodiment of the present invention and a pneumatic control device 1 using the servo valve unit 2. FIG. 2 shows the servo valve unit 2A of another embodiment. FIG. 3 shows the servo valve unit 2B of another embodiment. FIG. 4 shows the servo valve unit 2C of another embodiment and the pneumatic control device 1C using the servo valve unit 2C. FIG. 5 shows the servo valve unit 2D of another embodiment. FIG. 6 shows the servo valve unit 2E of another embodiment. FIG. 7 shows the servo valve unit 2F of another embodiment. FIG. 8 shows the servo valve unit 2G of another embodiment. FIG. 9 shows the servo valve unit 2H of another embodiment. FIG. 10 shows exemplary body parts 72-74. FIG. 11 shows a block diagram of a conventional pneumatic servo control. FIG. 12 shows a conventional spool type servo valve. FIG. 13 shows a conventional flapper type servo valve.

FIG. 1 shows a servo valve unit 2 according to an embodiment of the present invention and a pneumatic control device 1 using the servo valve unit 2. The pneumatic control device 1 includes a servo valve unit 2, a pneumatic cylinder 40, and a controller 50. The servo valve unit 2 has a valve body 10 in which a hollow space such as a common flow path 11, a supply flow path 12, an exhaust flow path 13, and a drive flow path 14 is formed. The unit body 10 can be an assembly of a plurality of parts made of metal or plastic.

One end of the supply flow path 12 is connected to the common flow path 11 via a first valve portion 20R capable of a pulse-type opening / closing operation according to the first electric pulse S1. The other end may have a connecting portion (joint or the like) 12a for connecting to a high pressure air source such as a compressor or a cylinder for supplying the high pressure air S. The connecting portion 12a may be formed at the first end portion 10a of the unit body 10. One end of the exhaust flow path 13 is connected to the common flow path 11 via a second valve portion 20L capable of a pulse-type opening / closing operation according to the second electric pulse S2. The other end of the exhaust flow path 13 is connected to the outside (for example, atmospheric pressure) through the opening 13a of the outer wall 10b of the unit body 10. One end of the drive flow path 14 is connected to the common flow path 11 at a branch point 64 described later. The other end of the drive flow path 14 may have a connecting portion (joint or the like) 14a for connecting to one cylinder chamber 41 of the pneumatic cylinder 40. The connecting portion 14a may be formed at the first end portion 10a of the unit body 10. In the figure, the common flow path 11, the supply flow path 12, and the exhaust flow path 13 extend in the axial direction X of the unit body 10, and the drive flow path 14 is drawn out in the radial direction from an appropriate position of the common flow path 11. There is.

The first valve portion 20R and the second valve portion 20L of the present embodiment have the same symmetrical structure (line symmetry). In the figure, for the sake of simplicity, the reference numerals of some members of the second valve portion 20L are omitted. In the following, when it is not necessary to distinguish between the first valve portion 20R and the second valve portion 20L, it is simply referred to as the valve portion 20. The valve portion 20 of the present embodiment comes into contact with / is separated from the nozzle (valve seat) 21 formed at the tips of the supply flow path 12 and the exhaust flow path 13 and the tip (valve seat) of the nozzle 21. A seal member (valve body) 22 that opens and closes 20, a magnetic body 23 that can move in the axial direction X integrally with the seal member 22, and a spring or the like that urges the seal member 22 and the magnetic body 23 in the axial direction X. It has a force member 24, a fixed magnetic core 25 arranged apart from the nozzle 21 in the axial direction X, and a solenoid 26 for exciting the fixed magnetic core 25. The magnetic body 23 may have a side wall 23a complementary to the outer shape of the nozzle 21 in order to guide the axial movement of the magnetic body 23.

When the solenoid 26 is not energized, the sealing member 22 comes into contact with the nozzle 21 by the force of the urging member 24, so that the valve portion 20 is OFF (closed state). When the solenoid 26 is energized, the magnetic force of the fixed magnetic core 25 is applied. The seal member 22 is separated from the nozzle 21 and the valve portion 20 is turned ON (open state).

The space between the nozzle space 11a around the seal member 22 of the first valve portion 20R and the nozzle space 11a around the seal member 22 of the second valve portion 20L is always connected by the common flow path 11. That is, the nozzle space 11a and the outer peripheral space 11b around the fixed magnetic core 25 are connected via a through groove 11c formed in the side surface of the nozzle 21 in the axial direction X, and the outer peripheral space 11b and the spring space 11d accommodating the urging member 24 are , Connected by a radial through hole 11e. A plurality of through grooves 11c and through holes 11e may be formed at intervals in the circumferential direction of the nozzle 21. The spring spaces 11d of the left and right valve portions 20R and 20L are connected by a connecting passage 11f.

As shown in FIG. 1, the unit body 10 has a first end portion 61a and a second end portion 61b located at both ends in the X direction, and a first end portion 61a and a second end portion 61b located between the first end portion 61a and the second end portion 61b. It has a drive mechanism arrangement portion 62a and a second drive mechanism arrangement portion 62b, and an intermediate portion 63 located between the first drive mechanism arrangement portion 62a and the second drive mechanism arrangement portion 62b.

In the present application, the structure, elements, and members (for example, the urging member 24, the fixed magnetic core 25, and the solenoid 26 of the present embodiment) for driving the seal member 22 are referred to as a "drive mechanism", and the first valve portion 20R and the first valve portion 20R The drive mechanisms of the two valve portions 20L are referred to as a "first drive mechanism" and a "second drive mechanism", respectively. The portion of the unit body 10 from the first drive mechanism arrangement portion 62a to the second drive mechanism arrangement portion 62b (that is, the portion of the first drive mechanism arrangement portion 62a, the intermediate portion 63, and the second drive mechanism arrangement portion 62b) is "driven." It is called "mechanism arrangement part". In the present embodiment, the first drive mechanism and the second drive mechanism are arranged in the first drive mechanism arrangement portion 62a and the second drive mechanism arrangement portion 62b, respectively. Preferably, the drive mechanism is housed in the space formed in the first drive mechanism arrangement portion 62a and the second drive mechanism arrangement portion 62b.

As shown in FIG. 1, the drive flow path 14 of the servo valve unit 2 branches from the common flow path 11 at a branch point 64 on the common flow path 11. The branch point 64 is located between the first drive mechanism accommodating portion 62a and the first end portion 61a (or between the first drive mechanism accommodating portion 62a and the tip of the nozzle 21). The drive flow path 14 of the present embodiment extends from the branch point 64 to the first end surface 10a (or the first end portion 61a).

In the present embodiment, the common flow path 11 extends through the drive mechanism accommodating portion in the X direction, and the supply flow path 12 and the drive flow path 14 penetrate the first end portion 61a in parallel in the X direction and are parallel to each other. The exhaust flow path 13 extends through the second end portion 61b in the X direction. The drive flow path 14 branches from the common flow path 11 at a predetermined position (branch point 64) on the path of the common flow path 11, and extends from the branch point 64 to the first end portion 61a (or the first end surface 10a). Exists. The branch point 64 is preferably located between the first end portion 61a (or the first end surface 10a) and the first drive mechanism accommodating portion 62a. Additionally or additionally, the branch point 64 is preferably located between the tip of the nozzle 21 of the first valve portion 20R and the first drive mechanism accommodating portion 62a on the path of the common flow path 11.

In another aspect, the branch point 64 is located between the second end portion 61b (or the second end surface 10b) and the second drive mechanism accommodating portion 62b, or the nozzle 21 of the second valve portion 20L on the path of the common flow path 11. It can be arranged between the tip and the second drive mechanism accommodating portion 62b. In this case, the drive flow path 14 preferably extends from the branch point 64 to the second end portion 61b (or the second end surface 10b), and the exhaust flow path 13 and the drive flow path 14 are inside the second end portion 61b. Is preferably extended in parallel with the X direction.

The position of the branch point 64, the arrangement of the drive flow path 14, and the extending direction of the supply flow path 12 and the drive flow path 14 at the first end portion 61a shall be the same for the servo valve units 2A to 2H described later. Can be done.

Hereinafter, the left half and the right half of the servo valve unit 2 may be referred to as servo valve elements 3A and 3B.

The pneumatic cylinder 40 has cylinder chambers 41 and 42, a piston 43, and an urging means 44 such as a spring that urges the piston 43, and the axial position of the piston 43 can be detected by the position sensor 45. The shapes of the cylinder chambers 41 and 42 are arbitrary, and may be a shape other than a cylindrical shape. The controller 50 generates the first and second electric pulses (DC pulses) S1 and S2. The first and second electric pulses S1 and S2 can be signals according to the position of the piston 43, a desired speed, and the like. The first and second electric pulses S1 and S2 may have a duty ratio depending on the position or speed of the piston 43. The controller 50 can be configured by, for example, a computer.

When the electric pulse S1 is turned on and the electric pulse S2 is turned off, the first valve portion 20R is turned on and the second valve portion 20L is turned off, and the high-pressure air S moves from the supply flow path 12 to the common flow path 11 and the drive flow path 14. It is supplied to the cylinder chamber 41 and the piston 43 can be moved to the left. When the electric pulse S1 is turned off and the electric pulse S2 is turned on, the first valve portion 20R is turned off and the second valve portion 20L is turned on, and the air in the cylinder chamber 41 is sent to the drive flow path 14, the common flow path 11, and the exhaust flow path. It is discharged to the outside through the opening 13a through the opening 13, and the piston 43 moves to the right by the force of the urging means 44. When both electric pulses S1 and S2 are turned off, the supply and exhaust to the cylinder chamber 41 is stopped.

In this way, by opening and closing the valve portions 20R and 20L in a pulsed manner by controlling the electric pulses S1 and S2, air pressure can be digitally supplied and / or the cylinder chamber 41 can be supplied and exhausted in a pulsed manner. it can. Precise and smooth position control of the piston 43 is achieved by speeding up the air supply / exhaust switching (air supply / stop switching, exhaust / stop switching). Basically, increasing the duty ratio of the electric pulses S1 or S2 increases the driving speed (or driving force) of the piston 43, and decreasing the duty ratio decreases the driving speed of the piston 43. Therefore, when the difference Δd between the current position and the target position of the piston 43 is large, the duty ratio is increased to move the piston 43 at high speed, and when the difference Δd is small, the duty ratio is decreased to decelerate the piston 43, and the duty ratio is zero ( The piston 43 can be stopped by setting the signal stop). However, for quick positioning and follow-up control, the speed of movement start is slow, and it is necessary to control such as gradually accelerating, decelerating, and stopping. In addition, it is necessary to control the speed to be freely changed according to the work contents of the robot. In these controls, it is essential to increase the speed of air supply / exhaust switching, and the maximum frequency of air supply / exhaust switching is preferably 100 Hz or higher, preferably 300 Hz or higher, more preferably 500 Hz or higher, and particularly preferably 1000 Hz or higher. The servo valve unit 2 of the present embodiment realizes high-speed switching of 300 to 500 Hz at the prototype stage, and is a humanoid robot arm unit prototype having a built-in pneumatic cylinder driven by the servo valve unit 2. It has been confirmed that the operation close to is possible. The inventor of the present application believes that 1000 Hz can be achieved by future improvements.

In the servo valve unit 2, it is not necessary to provide a branch point 64 or a drive flow path 14 in the drive mechanism arrangement portion. Since the drive mechanism arrangement portion (particularly, the intermediate portion 63) has a complicated structure due to the shape of the drive mechanism, wiring routing, etc., a branch point 64 and a drive flow path 14 are provided in the portion where such a structure is complicated. By not having it, it is possible to easily process and assemble the drive mechanism arrangement portion, and it is possible to reduce the dimension of the intermediate portion 63 (particularly the dimension in the X direction). As a result, the entire servo valve unit 2 can be miniaturized. Further, since the supply flow path 12 and the drive flow path 14 (or the exhaust flow path 13 and the drive flow path 14) are parallel to each other, it is easy to form the first end portion 61a (or the second end portion 61b). Become. In the servo valve units 2A to 2H described later, the position of the branch point 64, the arrangement of the drive flow path 14, the extending direction of the supply flow path 12 and the drive flow path 14 at the first end 61a, etc. are the same as those of the servo valve unit 2. Even in this case, the same effect as in the case of the servo valve unit 2 can be achieved.

The servo valve unit 2 may further have a muffling plate 16 for reducing exhaust noise. The sound deadening plate 16 is attached to the valve body 10 at a position overlapping the opening 13a (a position closing the opening 13a) with a gap G from the outer wall of the first end portion 10b. It is desirable that the sound deadening plate 16 has a sufficiently larger area than the opening 13a and is parallel to the first end portion 10b. The exhaust flow path 13 may have a hollow portion 13b having a large cross-sectional area on the opening 13a side. Since the air exhausted from the nozzle 21 through the cavity 13b and toward the outer periphery of the gap G gradually expands, the plosive sound at the time of opening to the atmosphere can be effectively alleviated. When the circumference of the cavity 13b is L, the gap is G, and the opening area of the nozzle 21 is SA1, it is desirable that L × G is approximately equal to SA1. The cross-sectional area of the exhaust flow path 13 may be increased in multiple steps or continuously from the nozzle 21 toward the opening 13a. If the gap G is increased or decreased according to the exhaust pressure by fixing the sound deadening plate 16 with the elastic body 16a having a spring property, the exhaust pressure is further leveled and the sound deadening effect is improved. Although the above configuration is not 100% muffling, it is possible to achieve a considerable muffling effect while achieving the space saving which is a major object of the present invention.

FIG. 2 shows the servo valve unit 2A of another embodiment, and the members common to the servo valve unit 2 are designated by the same reference numerals, or some reference numerals are omitted for the sake of brevity. The servo valve unit 2A may have the same structure as the servo valve unit 2 except for the left and right valve portions 20A. Each valve portion 20A may have the same symmetrical structure.

In the valve portion 20A, a disk-shaped elastic body 22A and a magnetic body 23A are used instead of the seal member 22 and the magnetic body 23 of the valve portion 20. In the disk-shaped elastic body 22A, the outer peripheral portion 22A1 is fixed to the unit body 10, the central portion constitutes a seal member 22A2 capable of closing the nozzle 21, and a plurality of openings 22A3 are formed in the middle thereof. The opening 22A3 is for connecting the nozzle space 11a and the outer peripheral space 11b. The disk-shaped elastic body 22A can be formed of the same material as the diaphragm. The magnetic body 23A is integrally formed with the disk-shaped elastic body 22A.

When the solenoid 26 is not energized, the sealing member 22A2 comes into contact with the nozzle 21 by the force of the urging member 24 and the valve portion 20A is turned off. When the solenoid 26 is energized, the sealing member 22A2 is ejected by the magnetic force of the fixed magnetic core 25. The valve portion 20A is turned on apart from the 21. The valve portion 20A can open and close the nozzle 21 reliably and at high speed in the same manner as the valve portion 20. Since the outer peripheral portion 22A1 is fixed to the unit body 10, the movement of the seal member 22A2 can be limited in the axial direction.

The servo valve unit 2A can also be opened and closed at the same high speed as the servo valve unit 2, and the use of the disc-shaped elastic body 22A can be expected to improve the durability of the valve portion 20A.

FIG. 3 shows the servo valve unit 2B of another embodiment. The servo valve unit 2B has a common flow path 11B, a supply flow path 12B, an exhaust flow path 13B, a drive flow path 14B, and two symmetrical valve portions 20B. Each valve portion 20B has a common flow path 11B, a nozzle 21B at the tip of the exhaust flow path 13B, a seal member 22B, and a telescopic member 23B.

The expansion / contraction member 23B is a material that expands / contracts depending on an applied voltage or the like. The elastic member 23B can be made of a piezoelectric element or a conductive resin. The elastic member 23B may use a single piece of elastic material having a certain dimension in the axial direction, but the amount of expansion and contraction can be increased by laminating a plurality of elastic materials.

When the telescopic member 23B expands, the seal member 22B abuts on the nozzle 21B and the valve portion 20B is turned off. When the telescopic member 23B contracts, the seal member 22B separates from the nozzle 21B and the valve portion 20B turns ON. The servo valve unit 2B can also achieve the same high-speed opening / closing operation as the servo valve unit 2.

FIG. 4 shows the servo valve unit 2C of another embodiment and the pneumatic control device 1C using the servo valve unit 2C. The servo valve unit 2C has a structure in which two servo valve units 2R and 2L are arranged so that the supply flow paths 12 face each other and are housed in a single unit body 10, and the four servo valve elements 3AL, 3AR, It is composed of 3BL and 3BR. The servo valve units 2R and 2L have the same configuration as the servo valve unit 2, but the two supply flow paths 12 are connected at the center and are drawn out from the side surface of the unit body 10. Each of the drive flow paths 14 is drawn out from the side surface of the valve body 10 and connected to each cylinder chamber of the pneumatic cylinder 40. It is preferable that the connecting portions 12a and 14a of the supply flow path 12 and the drive flow path 14 are provided on the same side surface and / or adjacent positions of the valve body 10.

The controller 50 applies electric pulses S1 and S2 according to the piston position of the pneumatic cylinder 40, a desired piston speed, and the like to the left and right servo valve units 2R and 2L. In this example, the electric pulse S1 is applied to the servo valve elements 3AL and 3BR, and the electric pulse S2 is applied to the servo valve elements 3BL and 3AR. As a result, the servo valve units 2R and 2L operate in the same manner as the servo valve unit 2 to drive the piston 43 to the left and right. In the wiring shown in the figure, the servo valve element 3AL and the servo valve element 3BR, the servo valve element 3BL and the servo valve element 3AR are excited at the same time, but they may be excited independently, and the servo valve elements 3AL, 3AR, respectively. The number of pulses of each electric pulse to 3BL and 3BR may be changed.

The servo valve unit 2C of FIG. 4 has a valve portion 20 similar to the servo valve unit 2, but servo valve units 2D and 2E (FIGS. 5 and 6) in which this is changed to a valve portion 20A or 20B are also possible. Any of the valve portions 20A to 20C may be used for one of the servo valve units 2R and 2L, and a different valve portion 20A to 20C may be used for the other. If high-speed opening and closing is possible, a valve portion of another embodiment may be used.

FIG. 7 shows the servo valve unit 2F of still another embodiment. In the servo valve unit 2F, two servo valve units 2F1 and 2F2 are arranged on one surface of the plate-shaped unit body 10F. The arrangement of the servo valve elements 3AL, 3AR, 3BL, and 3BR is an example, and other arrangements are possible. Servo valve unit 2F1 may be arranged on one surface and servo valve unit 2F2 may be arranged on the other surface. Servo valve elements 3AL and 3AR may be arranged on one surface and servo valve elements 3BL and 3AR may be arranged on the other surface. 3BR may be arranged. Communication of each flow path can be performed according to each of the above-described embodiments.

In the servo valve units 2 and 2A to 2F, since the extending directions of the common flow path 11, the supply flow path 12, the exhaust flow path 13, and the drive flow path 14 are all in the X direction, the servo valve units 2, 2A to 2F The action direction of the load generated inside is mainly the X direction. Therefore, the durability and failure resistance of the servo valve units 2, 2A to 2F can be improved only by increasing the strength in the X direction (load resistance and impact resistance). The above effect is remarkable when the unit body 10 is composed of a plurality of body parts, for example.
1. 1. When the common flow path 11, the supply flow path 12, the exhaust flow path 13 and / or the drive flow path 14 extends over a plurality of body parts.
2. 2. When the ends of the common flow path 11, the supply flow path 12, the exhaust flow path 13 and / or the drive flow path 14 are located at the boundary of adjacent body parts.
3. 3. The above effect is particularly remarkable when a force acts between adjacent body parts by the urging member 24, the seal member 26, or the like.

8 and 9 show servo valve units 2G and 2H in which the unit body 10 is composed of a plurality of body parts. (A) is a front view and (b) is a side sectional view. The servo valve units 2G and 2H are composed of body parts 71, 72L, 72R, 73L, 73R, 74L, 74R, 75L, 75R having a plurality of valve bodies (nine in the figure), and each body part is tightened with bolts or the like. It has the same configuration as the servo valve units 2C and 2D except that it is tightened in the X direction by the attachment 76. Since the servo valve units 2G and 2H are symmetrical, only the left half of the servo valve units 2G and 2H is shown in FIGS. 8 (a) and 9 (a), and a part of the right side of the body part 71 and a part on the right side of the body part 71. The body parts 72R, 73R, 74R, 75R on the right side are not shown. Hereinafter, when it is not necessary to distinguish between the left and right, the body parts 71, 72, 73, 74, 75 and the like are described.

In the servo valve units 2G and 2H, the unit body 10 is divided into a plurality of body parts to simplify the shape of each body part, which facilitates manufacturing. Then, by tightening the fastener 76 in the X direction, vibration between the unit parts during operation can be prevented, and durability and failure resistance can be improved.

As shown in FIG. 10, the body parts 72 and 74 may be a tubular bobbin case that houses the solenoid 26 wound around the bobbin 26a. The body parts 72 and 74 may have openings 72a and 74a on the body part 73 side. The body part 73 may have a magnetic wall portion 73a that closes the openings 72a and 74a, and a rod portion 73b in which the spring space 11d and the through hole 11e are formed. The body parts 72 to 74 may be made of a magnetic material. By surrounding the solenoid 26 with a magnetic body (body part 72 (74), magnetic wall portion 73a, rod portion 73b, and magnetic body 23), the driving force of the magnetic body 23 can be increased. In the servo valve units 2G and 2H, since the two solenoids 26 are arranged adjacent to each other with the single magnetic wall portion 73a interposed therebetween, further miniaturization, a small number of parts, easy assembly, and the like can be achieved.

In FIGS. 8 to 10, an example in which the unit body 10 is composed of a plurality of body parts is shown, but the servo valve units 2, 2A, 2B, 2E, and 2F of other embodiments are also substantially the same as the servo valve units 2C and 2D. In the same manner, the unit body 10 is composed of a plurality of body parts and tightened in the X direction with a fastener to achieve the same effect as the servo valve units 2G and 2H.

In the servo valve unit of the above embodiment, the pneumatic cylinder can be controlled with high accuracy without using a servo amplifier, and the machining accuracy of the conventional pneumatic servo valve is not required, and air bleeding is not required. is there. In particular, by setting the ON / OFF switching speed of the valve portion or the switching speed of air supply / exhaust to the pneumatic cylinder to 100 Hz or higher, the smooth moving speed and stop position control of the piston 43 becomes possible. By setting the switching speed to 300 Hz or higher, more preferably 500 Hz or higher, and even more preferably 1000 Hz or higher, the controllability of the piston moving speed and the stop position can be further improved. Since each cylinder chamber and flow path have a certain volume and a moment of inertia and some friction act on the piston, the piston operates smoothly without any trouble even if the supply and exhaust are switched in a pulse shape.

Of the above embodiments, prototypes of the servo valve units 2D and 2E are actually created in a small size of 20 × 25 × 70 mm, stable operation at a switching speed of up to 300 to 500 Hz, and a diameter of φ30 to 80 mm (stroke). It was confirmed that smooth and highly accurate control of a pneumatic cylinder (length 50 mm) can be realized. Furthermore, we actually created an arm unit of a humanoid humanoid robot that drives articulated joints with eight prototype servo valve units and eight pneumatic cylinders, and weighs up to 12.5 kg at the tip (palm). It was confirmed that it is possible to raise and lower freely with a weight. The actual operation was shot on video (not posted due to violation of public order and morals) (URL: https://youtu.be/mAEVIudfmno, https://youtu.be/7cVjNuoC_w8, https://youtu.be /FxbWDoIcv_k, https://youtu.be/5XO8cX9oREA, https://youtu.be/0qnxH6PFCwo). In this arm unit, all the above eight servo valve units are housed in the upper arm portion.

The signal of the position sensor may be digital or analog, but in order to achieve a certain degree of resolution with ultra-small size, it is better to perform AD conversion in the controller using an ultra-small analog sensor, which requires less space and wiring. Since it can be reduced, it is effective in designing a complicated articulated robot.

Since the motive for the development of the present invention is a humanoid robot (humanoid disaster robot), the application to the humanoid robot has been mainly described, but the present invention has various robots other than the humanoid robot (for example, lizard and mukade). It can also be applied to molds, multi-legged robots, four-legged animal robots, etc.). It can also be applied to robots other than disaster robots, such as nursing care assist and work assist robots. Since pneumatic pressure is compressible, it has the characteristic of being able to flexibly deal with reaction forces, so it can be in gentle contact with people. Furthermore, the present invention can be applied to fields other than robots. It is widely applicable to drive moving members in industrial equipment and household equipment.

The dimensions, shape, arrangement, number, materials, characteristics, etc. of the servo valve unit or the pneumatic control device or the elements constituting them described in the above embodiment are examples, and these are the scope of the invention described in the claims. And it can be changed as appropriate without changing its essence.

1,1C ... Pneumatic control device 2 (2R, 2L), 2A to 2F ... Servo valve unit 3A, 3B, 3AL, 3AR, 3BL, 3BR ... Servo valve element 10, 10F ... Unit Body (housing)
10a ... 1st end 10b ... 2nd ends 11, 11B ... Common flow path 11a ... Nozzle space 11b ... Outer space 11c ... Groove 11d ... Spring space 11e ... Through holes 11f ... Communication passages 12, 12B ... Supply flow paths 12a ... Connections 13, 13B ... Exhaust flow paths 13a ... Openings 13b ... Cavities 14, 14B ...・ ・ Drive flow path 14a ・ ・ ・ Connection part 16 ・ ・ ・ Sound deadening plate 16a ・ ・ ・ Elastic bodies 20, 20A, 20B ・ ・ ・ Valve part 20R ・ ・ ・ First valve part 20L ・ ・ ・ Second valve part 21 , 21B ... Nozzle 22, 22B, 22A2 ... Seal member 22A ... Disc-shaped elastic body 23, 23A ... Magnetic material 23a ... Side wall 23B ... Telescopic member 24 ... Biasing member 25 ... Fixed magnetic core 26 ... Solenoid 40 ... Pneumatic cylinders 41, 42 ... Cylinder chamber 43 ... Piston 44 ... Biasing means 45 ... Position sensor 50 ... Controller S1 , S2 ・ ・ ・ Electric pulse

In addition to this application
It is a unit body composed of multiple body parts arranged in the axial direction.
1st valve,
2nd valve,
A first seal member that opens and closes the first valve portion,
A second seal member that opens and closes the second valve portion,
A first drive mechanism that drives the first seal member in the axial direction by a first electric pulse,
A second drive mechanism that drives the second seal member in the axial direction by a second electric pulse,
A supply flow path extending in the axial direction between one end of the unit body and the first valve portion,
An exhaust flow path extending in the axial direction between the other end of the unit body and the second valve portion,
A common flow path connected to the supply flow path and the exhaust flow path via the first valve portion and the second valve portion, and
The unit body having a drive flow path connected to a pneumatic actuator and
A servo valve unit for driving a pneumatic actuator, which has a fastener for tightening the plurality of body parts in the axial direction, is disclosed.

Claims (7)

A servo valve unit for driving a pneumatic actuator.
A unit body having a first end and a second end,
1st valve and
2nd valve and
A first seal member that opens and closes the first valve portion, and
A second seal member that opens and closes the second valve portion, and
A first drive mechanism that drives the first seal member by a first electric pulse,
A second drive mechanism that drives the second seal member by a second electric pulse,
A supply flow path extending between the first end portion and the first valve portion,
An exhaust flow path extending between the second end and the second valve,
A common flow path connected to the supply flow path and the exhaust flow path via the first valve portion and the second valve portion, and
It has a drive flow path connected to the pneumatic actuator and has
The first drive mechanism and the second drive mechanism are arranged in a drive mechanism arrangement portion located between the first end portion and the second end portion.
The drive flow path is
A branch portion located between the drive mechanism arrangement portion and the first end portion branches from the common flow path and extends to the first end portion, or
A servo valve unit that branches from the common flow path at a branch portion located between the drive mechanism arrangement portion and the second end portion and extends to the second end portion. The branch portion is located between the drive mechanism arrangement portion and the first end portion.
The servo valve unit according to claim 1, wherein the supply flow path and the drive flow path extend in the axial direction of the unit body at the first end portion. It is a unit body composed of multiple body parts arranged in the axial direction.
1st valve,
2nd valve,
A first seal member that opens and closes the first valve portion,
A second seal member that opens and closes the second valve portion,
A first drive mechanism that drives the first seal member in the axial direction by a first electric pulse,
A second drive mechanism that drives the second seal member in the axial direction by a second electric pulse,
A supply flow path extending in the axial direction between one end of the unit body and the first valve portion,
An exhaust flow path extending in the axial direction between the other end of the unit body and the second valve portion,
A common flow path connected to the supply flow path and the exhaust flow path via the first valve portion and the second valve portion, and
The unit body having a drive flow path connected to the pneumatic actuator and
A servo valve unit for driving a pneumatic actuator, which has a fastener for tightening the plurality of body parts in the axial direction. The two unit bodies are arranged facing each other.
The supply channels of the two unit bodies are interconnected and
The servo valve unit according to any one of claims 1 to 3, wherein the supply flow path and the two drive flow paths of the two unit bodies are drawn out from the side surfaces of the unit body. The servo valve unit according to any one of claims 1 to 4, wherein the frequencies of the first electric pulse and the second electric pulse are 100 Hz or more. The first drive mechanism and the second drive mechanism have a solenoid.
The servo valve unit according to any one of claims 1 to 5, wherein the solenoids of the first drive mechanism and the second drive mechanism are arranged adjacent to each other with a single magnetic plate interposed therebetween. The servo valve unit according to any one of claims 1 to 6 and
With the pneumatic actuator
A device having a movable member operated by the pneumatic actuator.

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