JP2022156221A - Robot device - Google Patents

Abstract

To increase a degree of freedom of a robot arm including at least one artificial muscle, while suppressing a robot device from being enlarged in size as a whole.SOLUTION: A robot device according to the disclosure includes: a robot arm including at least one artificial muscle that receives supply of fluid to be activated; a fluid supply source; a pedestal to which the robot arm is fixed; a base part that supports the pedestal so that the pedestal can freely turn around a turning shaft; and a fluid adjustment part, supported by the robot arm or the pedestal, which adjusts pressure or flow volumes of fluid from the fluid supply source and supplies the artificial muscle with the fluid. The fluid adjustment part includes a pressure adjustment valve that has a spool that can move in an axial direction and adjusts pressure of fluid from the fluid supply source by balancing thrust in a plurality of axial directions acting on the spool, which is supported by the robot arm or the pedestal so that the spool of the pressure adjustment valve is in parallel with the turning shaft.SELECTED DRAWING: Figure 5

Description

The present disclosure relates to a robotic device including at least one artificial muscle.

Conventionally, a plurality of elastic expansion/contraction structures (artificial muscles), a plurality of joint shafts rotationally driven by a pair of corresponding elastic expansion/contraction structures, a hand for grasping an object, and a plurality of 3-port flow control electromagnetic 2. Description of the Related Art There is known an elastic actuator drive mechanism, which is a two-degree-of-freedom robot arm including a valve (driving device) (see, for example, Patent Document 1). Each elastic expansion/contraction structure of this elastic actuator drive mechanism includes a hollow tubular elastic body made of a rubber material and a mesh-like deformation direction regulating member covering the outer surface of the tubular elastic body. Both ends of the tubular elastic body are hermetically sealed by sealing members, and a compressible fluid such as air is supplied to the inside of the tubular elastic body through a tubular fluid passage member provided in the sealing member on one end side. be done. When a compressible fluid is supplied to the inside of the tubular elastic body, the tubular elastic body tries to expand mainly in the radial direction. be. Accordingly, by contracting the tubular elastic body by supplying the compressible fluid, the elastic expansion/contraction structure can be used as a direct acting actuator. Furthermore, by rotating the first and second joint shafts forward and backward by antagonistic driving of a pair of corresponding elastic expansion/contraction structures, it is possible to move the hand for grasping an object.

WO2012/081197

By the way, by making the robot arm with two degrees of freedom as described above rotatable with respect to the base portion, the degree of freedom of the robot arm can be increased. However, if the entire robot arm is rotatable with respect to the base part, the hose (piping) for supplying fluid to the artificial muscle will be long and the handling will be complicated, resulting in an increase in the overall size of the device. There is a risk of In addition, when the fluid adjustment unit for adjusting the fluid to the artificial muscle is rotated integrally with the robot arm, the fluid to the artificial muscle cannot be adjusted with high accuracy, and the controllability of the robot arm may deteriorate. be.

Therefore, the main object of the present disclosure is to increase the degree of freedom of a robot arm including at least one artificial muscle while suppressing an increase in the size of the entire robot apparatus, and to ensure good controllability of the robot arm. .

A robotic device of the present disclosure includes a robotic arm including at least one artificial muscle that operates by receiving a supply of fluid, a supply source of the fluid, a pedestal to which the robotic arm is fixed, a base portion that supports the pedestal so as to be rotatable about a rotation axis; and a base portion that is supported by the robot arm or the pedestal, adjusts the pressure or flow rate of the fluid from the supply source, and supplies the fluid to the artificial muscle. and a fluid adjustment unit, wherein the fluid adjustment unit has an axially movable spool, and balances the plurality of axial thrusts acting on the spool to adjust the pressure of the fluid from the supply source side. A regulating pressure regulating valve is included, the spool of the pressure regulating valve being supported by the robot arm or the pedestal so as to extend parallel to the pivot axis.

In the robot apparatus of the present disclosure, a robot arm including at least one artificial muscle is fixed to a pedestal, and the pedestal is rotatably supported by a base portion about a rotation shaft. Additionally, one of the robot arm and the pedestal supports a fluid regulator that regulates the pressure or flow of fluid from the source and supplies it to the artificial muscle. As a result, when the robot arm (and the pedestal) including the artificial muscle rotates with respect to the base, the fluid adjustment unit also rotates together with the robot arm around the rotation axis. Therefore, the fluid passage (piping) connecting the fluid adjustment unit and the artificial muscle can be shortened or routed as compared with the case where the fluid adjustment unit is arranged in the base portion and the fluid adjustment unit does not rotate around the rotation axis. can be facilitated. Further, the fluid adjustment unit includes a pressure adjustment valve that balances a plurality of axial thrusts acting on the axially movable spool to adjust the pressure of the fluid from the supply source side, and the spool of the pressure adjustment valve is supported by the robot arm or pedestal so that it extends parallel to the pivot axis. As a result, when the robot arm (pedestal) rotates about the rotation axis with respect to the base, the influence of the centrifugal force on the axial thrust acting on the spool can be eliminated. The pressure of the fluid to be supplied can be adjusted with high precision by the pressure regulating valve. As a result, it is possible to increase the degree of freedom of the robot arm including at least one artificial muscle while suppressing an increase in size of the entire robot apparatus, and to ensure good controllability of the robot arm.

1 is a schematic configuration diagram showing a robot device of the present disclosure; FIG. 1 is an enlarged view of a robotic device of the present disclosure; FIG. 1 is a schematic configuration diagram showing a liquid supply device of a robotic device of the present disclosure; FIG. FIG. 4 is a schematic configuration diagram showing another liquid supply device in the robot apparatus of the present disclosure; FIG. 4 is a schematic configuration diagram showing still another liquid supply device in the robot apparatus of the present disclosure; FIG. 6 is a system diagram showing a fluid adjustment unit of the liquid supply device of FIG. 5;

Next, embodiments for carrying out the invention of the present disclosure will be described with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing a robot device 1 of the present disclosure, and FIG. 2 is an enlarged view showing the robot device 1. As shown in FIG. A robot device 1 shown in these drawings includes a robot arm (robot body) 2 and a liquid supply device 10 (fluid supply device). The robot arm 2 includes a plurality of arms 3, a plurality of hydraulic actuators M as artificial muscles provided for each arm 3, and a hand portion (robot hand) 4 attached to the tip portion of the arm 3 on the tip side. and a multi-joint arm. Further, the liquid supply device 10 supplies hydraulic oil (liquid) to each hydraulic actuator M to hydraulically drive the robot arm 2 .

Each hydraulic actuator M of the robot arm 2 includes a tube T that expands under the pressure of hydraulic fluid and a braided sleeve S that covers the tube T, as shown in FIG. The tube T is formed in a cylindrical shape from an elastic material such as a rubber material having high oil resistance. An inlet/outlet IO for hydraulic oil is formed in a sealing member C on the base end side of the tube T (liquid supply device 10 side, lower end side in FIG. 2). The braided sleeve S is formed in a cylindrical shape by weaving a plurality of cords oriented in a predetermined direction so as to intersect each other, and is contractible in the axial and radial directions. As the cords forming the braided sleeve S, fiber cords, high-strength fibers, metal cords composed of ultrafine filaments, and the like can be used. Hydraulic fluid is supplied from the inlet/outlet IO into the tube T of the hydraulic actuator M to increase the pressure of the hydraulic fluid in the tube T, whereby the tube T expands radially and axially due to the action of the braided sleeve S. direction.

As shown in FIGS. 1 and 2, a plurality of arms (links) 3 are rotatably connected to each other via corresponding joints (pin joints). are arranged parallel to the corresponding arm 3 one by one. In this embodiment, each arm 3 is hollow, and a plurality of hoses H (see broken lines in FIG. 2) as liquid supply pipes are arranged inside each arm 3 . Each hose H is connected to an inlet/outlet IO formed in a sealing member C on the base end side of the corresponding hydraulic actuator M. As shown in FIG.

Further, as shown in FIG. 2, the arm 3 on the most proximal side (the side closest to the liquid supply device 10) is rotatably supported by a support member (link) 5 via a joint (pin joint). The support member 5 rotatably supports the sealing member C on the proximal side of each hydraulic actuator M corresponding to the arm 3 on the most proximal side. Furthermore, a connecting member 6 is fixed to the tip of the arm 3 on the most proximal side, and the connecting member 6 seals the distal end of each hydraulic actuator M corresponding to the arm 3 on the most proximal side. The stop member C is rotatably supported. As a result, the hydraulic pressures in the tubes T of the pair of hydraulic actuators M corresponding to the arm 3 on the proximal end side are made different from each other, thereby changing the rotation angles of the arm 3 and the connecting member 6 with respect to the support member 5. , force can be transmitted from the pair of hydraulic actuators M to the arm 3 and the connecting member 6 .

The connecting member 6 fixed to the arm 3 on the most proximal side rotates the sealing member C on the proximal side of each hydraulic actuator M corresponding to the arm 3 on the distal side connected to the arm 3. Freely support. Furthermore, connecting members 6 are also fixed to the distal end portions of the arms 3 other than the arm 3 on the most proximal side, and each connecting member 6 serves as the sealing member C on the distal end side of the corresponding pair of hydraulic actuators M. is rotatably supported. By making the hydraulic pressures in the tubes T of the pair of hydraulic actuators M corresponding to the arms 3 other than the arm 3 on the most proximal side different from each other, the arm 3 and the connecting member on the distal end side with respect to the connecting member 6 on the proximal side. 6 can be changed, and force can be transmitted from the pair of hydraulic actuators M to the arm 3 and the connecting member 6 on the tip side. A pair of hydraulic actuators M corresponding to each arm 3 are antagonistically driven with a state in which they are contracted in the axial direction by a predetermined amount as an initial state.

As shown in FIG. 3, the liquid supply device 10 includes a tank 11 as a pedestal including a liquid reservoir (fluid reservoir), and a rotation shaft RA (see the dashed line in FIG. 2) extending vertically through the tank 11. , a pump 14 as a fluid supply source arranged inside the tank 11, and a first hydraulic control device as a fluid adjustment unit arranged inside the tank 11, respectively. 15 and a second hydraulic control device 16 . The tank 11 is, for example, a cylindrical body with closed upper and lower ends, and can store hydraulic oil therein. In this embodiment, as shown in FIG. 2, the support member 5 of the robot arm 2 is fixed to the upper wall portion 11u of the tank 11 via bolts (not shown) or the like. That is, the robot arm 2 is supported by the tank 11 (upper wall portion 11 u) of the liquid supply device 10 .

The base part 12 is fixed to an installation location of the robot device 1 so as to be positioned below the robot arm 2 and the tank 11, or is mounted (fixed) on a carrier such as an automatic guided vehicle (AGV) (not shown). . Further, the base portion 12 is provided with a swing motor (rotating unit) that receives supply of hydraulic oil from a first hydraulic control device (another hydraulic control device) 15 and rotates the tank 11 around the rotation axis RA. I support 13. The swing motor 13 converts the energy of the liquid into rotary motion, and swings (rotates) the vane (piston) about its axis according to the pressure difference of the liquid supplied to both sides of the vane. . Accordingly, by operating the swing motor 13 with the hydraulic pressure from the first hydraulic control device 15, the robot arm 2 and the tank 11 can be integrally rotated around the rotation axis RA.

The pump 14 includes a pump portion 140 arranged in the tank 11, and an electric motor 141 and a reduction gear mechanism 142 as driving portions for driving the pump portion 140 so as to suck and discharge hydraulic oil in the tank 11. include. A pump unit 140 of the pump 14 includes a rotor connected to an electric motor 141 via a reduction gear mechanism 142, an external gear (drive gear) having a plurality of external teeth and rotating integrally with the rotor, and an external gear. and an internal gear (driven gear) that has a plurality of internal teeth that are one more than the total number of external teeth meshing with the external teeth of the gear pump mechanism and that is arranged eccentrically with respect to the external gear (any are also omitted). As shown in FIG. 3, the pump unit 140 pumps the hydraulic oil when the liquid level of the hydraulic oil in the tank 11 is at a predetermined lowest liquid level (the lowest liquid level during operation of the robot arm 2). It is fixed inside the tank 11 so as to be positioned below the surface. Further, the pump part 140 includes a suction port 14 i that opens downward below the fluid level (minimum fluid level) of the hydraulic oil in the tank 11 .

Further, in the present embodiment, the reduction gear mechanism 142 of the pump 14 is configured such that at least a portion of the hydraulic oil in the tank 11 is immersed in the hydraulic oil when the liquid level of the hydraulic oil in the tank 11 is at a predetermined maximum liquid level. 11. Further, the electric motor 141 is arranged in the tank 11 so as to be positioned above the liquid level of the hydraulic oil (highest liquid level) when the liquid level of the hydraulic oil in the tank 11 is the highest liquid level. This makes it possible to further reduce the stirring resistance when the electric motor 141 rotates. The pump section 140 of the pump 14 may include vanes and impellers. Also, the reduction gear mechanism 142 may be omitted from the pump 14 . Furthermore, when the electric motor 141 and the reduction gear mechanism 142 are configured to be submersible, both may be arranged below the liquid level (minimum liquid level) of the hydraulic oil in the tank 11 . As a result, the heat dissipation of the pump 14 can be further accelerated, and the noise of the pump 14 can be blocked by the working oil and the wall of the tank 11 .

As shown in FIG. 3, the first hydraulic control device 15 is arranged in the tank 11 so as to be positioned below the liquid level of the hydraulic oil when the liquid level of the hydraulic oil in the tank 11 is the minimum liquid level. , and connected to the discharge port of the pump portion 140 of the pump 14 via a pipe. As shown, the first hydraulic control device 15 includes a source pressure generation valve RV, a signal pressure generation valve (not shown) that generates a signal pressure, and the hydraulic pressure from the source pressure generation valve RV. and a solenoid valve SL0 that generates hydraulic pressure to the swing motor 13.

The original pressure generating valve RV adjusts the pressure of the hydraulic oil discharged from the pump section 140 according to the signal pressure from the signal pressure generating valve to generate the original pressure. As the signal pressure generating valve of the original pressure generating valve RV, for example, a linear solenoid valve that is energized and controlled by a control device (not shown) according to a request to the robot arm 2 is used. Further, in the present embodiment, the solenoid valve SL0 is a linear solenoid valve that regulates the hydraulic pressure (original pressure) from the original pressure generation valve RV in accordance with the current applied to the electromagnetic section. Further, the first hydraulic control device 15 includes a drain pipe L<b>1 that opens below the liquid level (minimum liquid level) of the hydraulic oil in the tank 11 . Drain oil generated as the oil pressure is adjusted by the original pressure generating valve RV and the solenoid valve SL0 is discharged into the tank 11 through the drain pipe L1.

As shown in FIGS. 2 and 3, the second hydraulic control device 16 is attached (fixed) to the inside of the tank 11, that is, to the inner surface of the upper wall portion 11u, and has a pipe L0 extending vertically inside the tank 11. , to the output port of the original pressure generating valve RV of the first hydraulic control device 15 . The second hydraulic control device 16 also includes the same number (plurality) of solenoid valves SLm as the hydraulic actuators M in the robot arm 2 . In this embodiment, each solenoid valve SLm is a linear valve that adjusts the hydraulic pressure (original pressure) from the original pressure generating valve RV in accordance with the current applied to the electromagnetic section to generate the hydraulic pressure to the corresponding hydraulic actuator M. Solenoid valve. A corresponding hose H is connected to the output port of each solenoid valve SLm via an oil passage or the like formed in the valve body of the second hydraulic control device 16 . Further, the second hydraulic control device 16 includes a drain pipe L2 that extends toward the liquid level of the hydraulic oil in the tank 11 and opens below the liquid level (minimum liquid level). Drain oil generated as the hydraulic pressure is adjusted by each solenoid valve SLm is also discharged into the tank 11 through the drain pipe L2.

A cable Kp for supplying electric power is connected to the electric motor 141 of the pump 14, and the cable Kp is opened above the liquid level (highest liquid level) of the hydraulic oil in the tank 11. It is pulled out from the cable hole 11h formed in the tank 11 concerned. Furthermore, a cable K1 for supplying power is also connected to the signal pressure generating valve and the solenoid valve SL0 of the first hydraulic control device 15, and the cable K1 is formed in the tank 11 in the same manner as the cable Kp of the pump 14. It is pulled out to the outside from the cable hole 11h. A cable K2 for supplying electric power is also connected to each solenoid valve SLm of the second hydraulic control device 16, and the cable K2 is connected to a cable hole formed in the tank 11 similarly to the cables Kp and K1. It is pulled out from 11h. Further, each cable Kp, K1, K2 is connected to a domestic power source, a battery, or the like via a control device (not shown). In this embodiment, a seal member for sealing gaps between the wall of the tank 11 and the cables Kp, K1, K2 is provided in the cable hole 11h. However, when the liquid supply device 10 is fixed to the installation location, the seal member may be omitted.

As described above, in the robot device 1, the robot arm 2 including a plurality of hydraulic actuators M as artificial muscles is supported by the tank 11 that stores hydraulic oil (liquid). Further, inside the tank 11, there are provided a pump portion 140 of the pump 14 for sucking and discharging hydraulic oil, and a second pump portion 140 for regulating (adjusting) the pressure of the hydraulic oil from the pump portion 140 and supplying it to each hydraulic actuator M. A hydraulic control device 16 is arranged. This eliminates the need for a housing that houses the tank 11, and eliminates the piping that connects the tank 11, the pump 14, and the second hydraulic control device 16. Therefore, the liquid supply device 10 can be downsized, and the robot device 1 can be used. It is possible to make the whole compact. Furthermore, by arranging the pump part 140 of the pump 14 in the tank 11 (hydraulic oil), the hydraulic oil in the tank 11 promotes the heat dissipation of the pump 14 and the like, and the noise is blocked by the tank 11 and the hydraulic fluid. can do. As a result, it is possible to reduce heat generation and noise while making the robot apparatus 1 more compact.

Further, in the robot device 1, the robot arm 2 is fixed to the tank 11 as a base, and the tank 11 is supported by the base portion 12 so as to be rotatable about the rotation axis RA. Furthermore, the tank 11 supports a second hydraulic control device 16 as a fluid adjustment unit that adjusts the pressure of hydraulic fluid from a pump 14 as a fluid supply source and supplies it to a plurality of hydraulic actuators (artificial muscles) M. ing. As a result, when the robot arm 2 (and the dunk 11) including the plurality of hydraulic actuators M rotates with respect to the base portion 12, the second hydraulic control device 16 including the plurality of solenoid valves SLm is also integrated with the robot arm 2. , rotates around the rotation axis RA. Therefore, compared to the case where the second hydraulic control device 16 is arranged on the base portion 12 and the second hydraulic control device 16 does not rotate around the rotation axis RA, the second hydraulic control device 16 and the hydraulic actuators It is possible to shorten the length of the hose H (piping) or the like that forms a fluid passage connecting M and facilitate the handling. As a result, it is possible to increase the degree of freedom of the robot arm 2 including the plurality of hydraulic actuators M while suppressing an increase in the overall size of the robot apparatus 1 .

Furthermore, in the robot device 1 , the second hydraulic control device 16 is supported by the upper wall portion 11 u of the tank 11 so as to be positioned above the liquid reservoir and the pump 14 . As a result, it is possible to drain the hydraulic fluid leaking from the plurality of solenoid valves SLm and the control valve PCV directly into the tank 11 from the valve body via the drain pipe L2. It is possible to simplify the structure for suppressing liquid leakage from the body) and the structure for guiding the leaked hydraulic oil into the tank 11 . As a result, it is possible to suppress the size and complexity of the structure of the liquid supply device 10 (robot device 1) and to reduce the cost.

Further, in the above-described embodiment, the electric motor 141 and the reduction gear mechanism 142 as the driving portion of the pump 14 are arranged inside the tank 11 so as to be positioned above the pump portion 140 . By arranging the driving portion of the pump 14 including the electric motor 141 in the tank 11 in this manner, the operating sound of the pump 14 can be effectively blocked by the tank 11 .

However, like the liquid supply device 10B shown in FIG. 4, the electric motor 141 and the reduction gear mechanism 142 serving as the driving portion of the pump 14B may be arranged outside the tank 11B. As a result, it is possible to secure a sufficient amount of hydraulic oil that can be stored in the tank 11B while reducing the size of the tank 11B. Further, the liquid supply device 10B can eliminate the influence of the liquid shaking in the tank 11B on the electric motor 141, and is preferably applied particularly to the robot device 1 mounted on the automatic guided vehicle. Furthermore, in the robot apparatus 1, the entire pump 14 (pump section 140 and driving section) may be arranged outside the tanks 11 and 11B.

In the above embodiment, the robot arm 2 is supported by the upper wall portion 11u of the tank 11, and the second hydraulic control device 16 is attached to the inner surface of the upper wall portion 11u. As a result, the hose (liquid supply pipe) H for supplying hydraulic fluid from the second hydraulic control device 16 to each hydraulic actuator M can be further shortened and the handling of each hose H can be made extremely easy. Become. However, the second hydraulic control device 16 may be attached to the inner surface of the wall portion of the tank 11 that supports the robot arm 2. For example, when the robot arm 2 is supported by the side wall portion of the tank 11, the side wall portion may be attached to the inner surface of the

Further, the liquid supply devices 10 and 10B include a base portion 12 that rotatably supports the tank 11, a swing motor 13 that is supported by the base portion 12 and serves as a rotating unit that rotates the tank 11, and the tank 11. A first hydraulic pressure that is arranged in the tank 11 so as to be positioned below the liquid level (minimum liquid level) of the hydraulic oil in the tank 11 and that regulates the pressure of the hydraulic oil from the pump section 140 and supplies it to the swing motor 13 and a controller 15 . Thereby, the robot arm 2 can be rotated integrally with the tank 11 . In addition, as in the above embodiment, the primary pressure is generated by the first hydraulic control device 15 (original pressure generation valve RV) arranged below the liquid level (minimum liquid level) of the hydraulic oil in the tank 11. By supplying the pressure to the second hydraulic control device 16 above, the original pressure can be efficiently generated and the load on the pump 14 can be reduced.

In addition, the first and second hydraulic control devices 15 and 16 each include a drain pipe L1 or L2 that opens below the liquid level (minimum liquid level) of the hydraulic oil in the tank 11, and regulates the pressure of the hydraulic oil, respectively. Drain oil (surplus liquid) generated along with the above is discharged into the tank 11 from the drain pipe L1 or L2. As a result, it is possible to prevent air bubbles from being generated when hydraulic oil flows out from the drain pipes L1 and L2, thereby preventing the pump section 140 from sucking air. However, the drain pipe L<b>2 of the second hydraulic control device 16 may open above the liquid surface of the hydraulic oil in the tank 11 . In addition, in the liquid supply devices 10 and 10B, the suction port 14i of the pump portion 140 opens downward below the liquid level (minimum liquid level) of the hydraulic oil in the tank 11 . As a result, it is possible to better prevent the pump portion 140 from sucking air.

Further, the first and second hydraulic control devices 15, 16 each include a solenoid valve SL0 or SLm powered via a cable K1 or K2, respectively, from outside the tank 11, the cables K1, K2 is pulled out from a cable hole 11h formed in the tank 11 so as to open above the liquid level (highest liquid level) of the hydraulic oil. In addition, a cable Kp for supplying electric power is connected to the electric motor 141 of the pump 14, and the cable Kp is also pulled out from the cable hole 11h of the tank 11 to the outside. As a result, leakage of hydraulic oil from the cable hole 11h through which the cables Kp, K1, and K2 are inserted can be suppressed satisfactorily.

FIG. 5 is a schematic configuration diagram showing another liquid supply device 10C applicable to the robot device 1, and the figure is a system diagram showing a second hydraulic control device 16C of the liquid supply device 10C. Among the constituent elements of the liquid supply device 10C, the same elements as those of the liquid supply device 10 and the like are denoted by the same reference numerals, and overlapping descriptions are omitted.

As shown in FIG. 5, the liquid supply device (fluid supply device) 10C also includes a tank 11 as a pedestal for the robot arm 2 including a liquid reservoir (fluid reservoir) and a rotation shaft extending vertically through the tank 11. A base portion 12 which supports a swing motor 13 as a rotating unit and which is rotatably supported around the RA; a pump 14 as a fluid supply source disposed inside the tank 11; includes a first hydraulic control device 15 and a second hydraulic control device 16C as fluid adjustment units arranged in the .

The second hydraulic control device 16C of the liquid supply device 10C is also mounted (fixed) inside the tank 11, that is, on the inner surface of the upper wall portion 11u, and receives the first hydraulic pressure via a pipe L0 extending vertically inside the tank 11. It is connected to the output port of the original pressure generating valve RV of the control device 15 . The second hydraulic control device 16C also includes, as fluid control valves (pressure control valves), the same number of solenoid valves SLm as the hydraulic actuators M in the robot arm 2 (eg, six), and control valves PCV.

The plurality of solenoid valves SLm are linear solenoid valves having a configuration common to those included in the liquid supply device 1, and are housed (held) in a valve body (valve holding member) B2 of the second hydraulic control device 16C. and controlled by a control device (not shown). As shown in FIG. 6, the solenoid valve SLm includes an electromagnetic portion 50e that is energized and controlled by the control device, a spool 50s that is axially movably disposed within a sleeve held by the valve body B2, and a spool 50s. toward the electromagnetic portion 50e side (from the output port 50o side to the input port 50i side, the upper side in FIG. 6). Further, the solenoid valve SLm includes an input port 50i, an output port 50o, a feedback port 50f communicating with the output port 50o, and a drain port 50d communicating with the input port 50i and the output port 50o.

An input port 50i of each solenoid valve SLm communicates with the pipe L0 via an oil passage formed in the valve body B2. A signal pressure to the control valve PCV is output from the output port 50o of one solenoid valve SLm among the plurality of solenoid valves SLm. In addition, the output ports 50o of the remaining five solenoid valves SLm communicate with hydraulic fluid inlets and outlets IO of the corresponding hydraulic actuators M (tube T) via oil passages and hoses H formed in the valve body B2. . Furthermore, the drain port 50d of each solenoid valve SLm communicates with the drain pipe L2 via an oil passage formed in the valve body B2.

In this embodiment, the solenoid valve SLm is a normally closed valve that opens when current is supplied to the electromagnetic part 50e. Axially move spool 50s into communication with. As a result, the thrust force acting on the spool 50s toward the electromagnetic portion 50e side due to the thrust generated by the power supply to the electromagnetic portion 50e (coil), the biasing force of the spring 50sp, and the hydraulic pressure supplied from the output port 50o to the feedback port 50f. By balancing , the hydraulic oil from the pump 14 side supplied to the input port 50i is accurately adjusted to the desired pressure, and the signal pressure from the output port 50o to the control valve PCV or the drive to the hydraulic actuator M It becomes possible to flow out as pressure.

In addition, by feeding back the hydraulic pressure (signal pressure or driving pressure) supplied to the plurality of hydraulic actuators M to the solenoid valve SLm, the robot arm 2 driven by the hydraulic actuator M as an artificial muscle is fed back to the hydraulic pressure. When an external force is applied from a source other than the actuator M, it is possible to absorb fluctuations in hydraulic pressure according to changes in the volume of the tube T of the hydraulic actuator M caused by the external force. In addition, after the external force disappears, it is possible to quickly supply hydraulic pressure (driving pressure) to the hydraulic actuator M according to the demand.

The control valve PCV adjusts the pressure of the working oil from the pipe L0 according to the signal pressure from the corresponding solenoid valve SLm and supplies it to the tube T of the hydraulic actuator M determined in advance. The control valve PCV is a spool valve that includes a spool 60s that is axially movably disposed within the valve body B2 and a spring 60sp that biases the spool 60s. 6, the control valve PCV includes an input port 60i, an output port 60o, a feedback port 60f, a signal pressure input port 60c, and a drain port 60d.

The input port 60i communicates with the pipe L0 via an oil passage formed in the valve body B2. The output port 60o communicates with the hydraulic fluid inlet/outlet IO of the corresponding hydraulic actuator M (tube T) via an oil passage formed in the valve body B2, a hose H, and the like. The feedback port 60f communicates with the output port 60o through an oil passage formed in the valve body B2. The signal pressure input port 60c communicates with the output port 50o of the one solenoid valve SLm through an oil passage formed in the valve body B2. The drain port 60d communicates with the drain pipe L2 via an oil passage formed in the valve body B2.

The spool 60s of the control valve PCV moves in the axial direction against the biasing force of the spring 60sp by the action of the signal pressure from the one solenoid valve SLm corresponding to the current applied to the electromagnetic part 50e. . This balances the thrust applied to the spool 60s by the action of the signal pressure, the biasing force of the spring 60sp, and the thrust acting on the spool 60s by the hydraulic pressure (driving pressure) supplied from the output port 60o to the feedback port 60f. As a result, a portion of the hydraulic oil supplied to the input port 60i from the pump 14 side is drained appropriately through the drain port 60d and supplied from the output port 60o to the tube T of the corresponding hydraulic actuator M. Hydraulic oil can be precisely adjusted to a desired pressure.

As shown in FIG. 5, the second hydraulic control device 16C (valve body B2) has a plurality of solenoid valves SLm, which are pressure regulating valves, and spools 50s and 60s of control valves PCV. It is supported by the upper wall portion 11u of the tank 11 so as to extend parallel to the driving axis RA. That is, the plurality of solenoid valves SLm are held by the valve body B2 (tank 11) so that the axial direction of the spool 50s (see the dashed line in FIG. 5) is parallel to the robot arm 2 and the rotation axis RA of the tank 11. be (supported) The control valve PCV is also held (supported) by the valve body B2 (tank 11) so that the axial direction of the spool 60s (see the dashed line in FIG. 5) is parallel to the rotation axis RA of the robot arm 2 and the tank 11. be done.

As described above, in the liquid supply device 10C as well, the tank 11 as a pedestal to which the robot arm 2 (support member 5) is fixed is supported by the base portion 12 so as to be rotatable about the rotation axis RA. Furthermore, the tank 11 supports a second hydraulic control device 16C as a fluid adjustment unit that adjusts the pressure of hydraulic fluid from a pump 14 as a fluid supply source and supplies it to a plurality of hydraulic actuators (artificial muscles) M. ing. As a result, when the robot arm 2 (and the dunk 11) including the plurality of hydraulic actuators M rotates with respect to the base portion 12, the second hydraulic control device 16C including the plurality of solenoid valves SLm is also integrated with the robot arm 2. , rotates around the rotation axis RA. Therefore, compared to the case where the second hydraulic control device 16C is arranged in the base portion 12 and the second hydraulic control device 16C does not rotate around the rotation axis RA, the second hydraulic control device 16C and the hydraulic actuators It is possible to shorten the length of the hose H (piping) or the like that forms a fluid passage connecting M and facilitate the handling.

The second hydraulic control device 16C of the liquid supply device 10C has axially movable spools 50s and 60s, and balances a plurality of axial thrusts acting on the spools 50s and 60s so that the pressure from the pump 14 side is reduced. It includes a plurality of linear solenoid valves SLm and control valves PCV that adjust the pressure of hydraulic fluid, and spools 50s and 60s are supported by tank 11 so as to extend parallel to pivot axis RA. As a result, when the robot arm 2 (and the tank 11) rotates about the rotation axis RA with respect to the base portion 12, the influence of the centrifugal force on the axial thrust acting on the spools 50s and 60s is eliminated. Therefore, the pressure of hydraulic fluid supplied to each hydraulic actuator (artificial muscle) M can be adjusted with high precision by the plurality of solenoid valves SLm and control valves PCV.

As a result, in the robot apparatus 1, it is possible to increase the degree of freedom of the robot arm 2 including the plurality of hydraulic actuators M and to ensure good controllability of the robot arm 2 while suppressing an increase in the size of the entire apparatus. can.

Further, the second hydraulic control device 16C (valve body B2) of the liquid supply device 10C is supported by the upper wall portion 11u of the tank 11 as a pedestal. As a result, when the robot arm 2 (tank 11) rotates about the rotation axis RA with respect to the base portion 12, regardless of the posture of the robot arm 2, the axial direction acting on the spools 50s and 60s is It is possible to eliminate the influence of centrifugal force on thrust.

Further, by attaching the second hydraulic control device 16C to the inner surface of the upper wall portion 11u of the tank 11, a hose (liquid supply pipe) H for supplying hydraulic fluid from the second hydraulic control device 16C to each hydraulic actuator M can be further shortened and the handling of each hose H can be made extremely easy. However, if the robot arm 2 is supported by the side wall of the tank 11, for example, the second hydraulic control device 16C may be attached to the inner surface of the side wall.

Furthermore, the second hydraulic control device 16C may be supported by the arm 3 of the robot arm 2, the support member 5, the connecting member 6, and the like. Furthermore, the plurality of solenoid valves SLm and control valves PCV may be supported by the arm 3 of the robot arm 2, the support member 5, the connecting member 6, etc. so as to be positioned near the corresponding hydraulic actuators M. FIG.

Incidentally, in the liquid supply device 10-10C, at least one of the solenoid valves SLm and SL0 may be a normally open valve. In this case, the normally open valve balances the thrust from the electromagnetic section and the thrust from the hydraulic pressure supplied to the feedback port so as to act in the same direction as the thrust from the electromagnetic section with the biasing force of the spring. There may be. Furthermore, at least one of the solenoid valves SLm and SL0 does not have a dedicated feedback port, and is configured so that the output pressure (driving pressure) acts on the spool as feedback pressure inside a sleeve that accommodates the spool. (See, for example, Japanese Unexamined Patent Application Publication No. 2020-41687). Similarly, the control valve PCV may also be configured such that the output pressure (driving pressure) acts on the spool as feedback pressure inside the spool. Furthermore, in the liquid supply device 10C, the control valve PCV may be omitted, and hydraulic pressure (driving pressure) may be supplied to all the hydraulic actuators M from the corresponding solenoid valves SLm.

In addition, the liquid supply device 10-10C functions as a fluid adjustment valve (fluid adjustment unit) to supply the liquid to the hydraulic actuator M so that the fluid pressure (fluid pressure) detected by a pressure sensor, for example, becomes the required pressure. It may include a flow control valve for controlling the flow rate of (fluid). Further, the liquid supply device 10-10C may supply the hydraulic actuator M with a liquid other than hydraulic oil such as water or a gas such as air. Also, the liquid supply device 10-10C may include an accumulator (pressure accumulator) that stores the hydraulic pressure generated by the pump 14. FIG.

Furthermore, the robot apparatus 1 may include only one joint, or may include only one or two hydraulic actuators M as artificial muscles. Further, the robot device 1 is not limited to one including the robot arm 2 having at least one hydraulic actuator M and the hand portion 4, and includes at least one hydraulic actuator M, a tool such as a drill bit, a switch, or the like. It may also include a robot arm to which an element other than the hand unit 4, such as a pressing member that presses, is attached to the hand. Furthermore, the robot device 1 may be a walking robot, a wearable robot, or the like.

Further, the robot arm 2 of the robot device 1 may include a swing motor (for example, a swing motor that rotates the base (wrist portion) of the hand portion 4) as an actuator that drives the arm 3. FIG. That is, the robot main body of the robot apparatus 1 may include at least one of the hydraulic actuator M as an artificial muscle and the swing motor. Furthermore, the robot arm 2 of the robot device 1 may include a hydraulic cylinder such as a hydraulic cylinder as an actuator for driving the arm 3 . Moreover, it is not always necessary to provide a plurality of pairs of hydraulic actuators (artificial muscles) M for all of the two arms 3 and the like that are connected via a joint. One or a plurality of hydraulic actuators may be connected to an elastic body such as a spring or rubber material arranged to oppose the hydraulic actuators. Additionally, in the robot apparatus 1 , the tanks 11 and 11B may be supported by a robot body such as the robot arm 2 . In this case, the second hydraulic control devices 16, 16C are preferably attached to the inner surfaces of the walls of the tanks 11, 11B supported by the robot arm 2. As a result, the length of the hose H as the liquid supply pipe can be shortened, and the handling of each hose H can be facilitated.

Furthermore, in the above-described embodiment, the hydraulic actuator M as an artificial muscle includes a tube T that is supplied with hydraulic oil and expands in the radial direction and contracts in the axial direction in response to an increase in the hydraulic pressure inside the tube T; Although it is a McKibben-type artificial muscle including a braided sleeve S covering the tube T, the configuration of the hydraulic actuator M in the robot device 1 is not limited to this. That is, the hydraulic actuator M may include a tube that expands in the radial direction and contracts in the axial direction when supplied with fluid. and comprising an outer tubular member coaxially disposed outside the inner tubular member and a fiber layer disposed between the inner tubular member and the outer tubular member. It may be a pressure actuator (see, for example, JP-A-2011-137516).

As described above, the robotic device of the present disclosure is a robot that includes a robotic arm (2) that includes at least one artificial muscle (M) that operates when supplied with fluid, and a fluid supply source (14). A device (1), comprising a pedestal (11) to which the robot arm (2) is fixed, and a base (12) to support the pedestal (11) so as to be rotatable about a rotation axis (RA). and a fluid adjustment unit (16) supported by the robot arm (2) or the pedestal (11), adjusting the pressure or flow rate of the fluid from the supply source (14) and supplying it to the artificial muscle (M) , 16C, SLm, PCV), wherein the fluid adjustment portion (16C) has axially movable spools (50s, 60s) and a plurality of the axially moving spools (50s, 60s) acting on the spools (50s, 60s). including a pressure regulating valve (SLm, PCV) that balances the thrust of and regulates the pressure of the fluid from the supply source (14) side, the spool (50s, 60s) of the pressure regulating valve (SLm, PCV) is supported by the robot arm (2) or the pedestal (11) so as to extend parallel to the rotation axis (RA).

In the robot apparatus of the present disclosure, a robot arm including at least one artificial muscle is fixed to a pedestal, and the pedestal is rotatably supported by a base portion about a rotation shaft. Additionally, one of the robot arm and the pedestal supports a fluid regulator that regulates the pressure or flow of fluid from the source and supplies it to the artificial muscle. As a result, when the robot arm (and the pedestal) including the artificial muscle rotates with respect to the base, the fluid adjustment unit also rotates together with the robot arm around the rotation axis. Therefore, the fluid passage (piping) connecting the fluid adjustment unit and the artificial muscle can be shortened or routed as compared with the case where the fluid adjustment unit is arranged in the base portion and the fluid adjustment unit does not rotate around the rotation axis. can be facilitated. Further, the fluid adjustment unit includes a pressure adjustment valve that balances a plurality of axial thrusts acting on the axially movable spool to adjust the pressure of the fluid from the supply source side, and the spool of the pressure adjustment valve is supported by the robot arm or pedestal so that it extends parallel to the pivot axis. As a result, when the robot arm (pedestal) rotates about the rotation axis with respect to the base, the influence of the centrifugal force on the axial thrust acting on the spool can be eliminated. The pressure of the fluid to be supplied can be adjusted with high precision by the pressure regulating valve. As a result, it is possible to increase the degree of freedom of the robot arm including at least one artificial muscle while suppressing an increase in size of the entire robot apparatus, and to ensure good controllability of the robot arm.

Further, the fluid adjustment parts (16, 16C) may be supported by the base (11).

As a result, when the robot arm (pedestal) rotates about the rotation axis with respect to the base, the influence of the centrifugal force on the axial thrust acting on the spool is reduced regardless of the posture of the robot arm. It is possible to eliminate it.

Further, the pressure regulating valve may be a linear solenoid valve (SLm) having an electromagnetic part (50e) that generates thrust to move the spool (50s) in the axial direction.

Further, the pressure regulating valve has an input port (60i), an output port (60o) and a signal pressure input port (60c), and at least by the action of the signal pressure supplied to the signal pressure input port (60c) By balancing the force applied to the spool (60s) and the force applied to the spool (60s) by the action of the pressure of the fluid at the output port (60o), It may be a control valve (PCV) that adjusts the pressure of the fluid and outputs it from the output port (60o). The control valve (PCV) has a spool (50s) movable along the extending direction of the shaft (RA) and an electromagnetic part (50e) for generating thrust to move the spool (50s) in the extending direction. may include a linear solenoid valve (SLm) for supplying the signal pressure to the signal pressure input port (60c).

Further, the robot body (2) may be supported by the upper wall (11u) of the tanks (11, 11B), and the liquid adjustment unit (16) is mounted on the inner surface of the upper wall (11u). may be attached.

Furthermore, the liquid adjustment units (15, 16) include drain pipes (L1, L2) that open below the liquid surface in the tanks (11, 11B), and are used to adjust the pressure or the flow rate. The surplus liquid generated along with this may be discharged from the drain pipes (L1, L2) into the tanks (11, 11B). As a result, it is possible to prevent air bubbles from being generated when the liquid flows out from the drain pipe, thereby suppressing the suction of air by the pump section.

Further, the pump section (140) may include a suction port (14i) that opens below the liquid level in the tank (11, 11B). As a result, it is possible to better prevent the pump section from sucking air.

Further, the drive section of the pump (14) may include an electric motor (141) and may be arranged in the tank (11) so as to be positioned above the pump section (140). By arranging the drive unit including the electric motor inside the tank in this way, it is possible to satisfactorily block the operation noise of the pump by the tank.

Further, the liquid adjustment unit (15, 16) includes at least one electromagnetic valve (SL0, SLm) to which power is supplied from the outside of the tank (11, 11B) via cables (K1, K2). and the cables (K1, K2) are routed from holes (11h) formed in the tanks (11, 11B) so as to open above the liquid surface in the tanks (11, 11B). It may be pulled out to the outside. As a result, it is possible to satisfactorily suppress leakage of liquid from the hole through which the cable is inserted.

Further, the robot body (2) includes a plurality of the hydraulic actuators (M), the liquid adjusting unit (16) and the ends of the corresponding hydraulic actuators (M) on the tank (11, 11B) side. It may also include a plurality of liquid supply pipes (H) connected to the portions (C, IO).

Further, the liquid supply device (10, 10B) includes a base portion (12) that rotatably supports the tanks (11, 11B), and is supported by the base portion (12) to receive the supply of the liquid. a rotating unit (13) for rotating the tanks (11, 11B) by means of a rotating unit (13) arranged in the tanks (11, 11B) so as to be positioned below the liquid surface in the tanks (11, 11B); and another liquid adjustment unit (15) that adjusts the pressure or flow rate of the liquid from the pump section (140) and supplies it to the rotating unit (13). This makes it possible to rotate the robot main body and the liquid supply device (tank) integrally.

Further, the hydraulic actuator (M) may comprise a tube (T) that radially expands and axially contracts when supplied with the liquid.

It goes without saying that the invention of the present disclosure is not limited to the above-described embodiments, and various modifications can be made within the scope of the present disclosure. Furthermore, the above-described embodiment is merely one specific form of the invention described in the Summary of the Invention column, and does not limit the elements of the invention described in the Summary of the Invention column.

INDUSTRIAL APPLICABILITY The invention of the present disclosure can be used in the manufacturing industry of robot devices including at least one artificial muscle.

1 robot device, 2 robot arm, 11 tank (pedestal), 12 base part, 14 pump (supply source), 16, 16C second hydraulic control device, 50e electromagnetic part, 50s, 60s spool, 60i input port, 60o output port , 60c signal pressure input port, M fluid actuator (artificial muscle), PCV control valve, RA pivot shaft, SLm solenoid valve.

Claims (4)

A robotic device comprising a robotic arm including at least one artificial muscle supplied with a fluid to operate; and a source of the fluid,
a pedestal to which the robot arm is fixed;
a base portion that supports the pedestal so as to be rotatable around a rotation shaft;
a fluid adjustment unit that is supported by the robot arm or the pedestal, adjusts the pressure or flow rate of the fluid from the supply source, and supplies the fluid to the artificial muscle;
with
The fluid adjustment unit has an axially movable spool and includes a pressure adjustment valve that balances the plurality of axial thrusts acting on the spool to adjust the pressure of the fluid from the supply source side. , a robot device supported by the robot arm or the pedestal so that the spool of the pressure regulating valve extends parallel to the pivot axis. 2. The robot apparatus according to claim 1, wherein said fluid adjustment section is supported by said base. The robot device according to claim 1 or 2,
The robot device, wherein the pressure regulating valve is a linear solenoid valve having an electromagnetic section that generates a thrust for moving the spool in the axial direction. In the robot apparatus according to any one of claims 1 to 3,
The pressure regulating valve has an input port, an output port and a signal pressure input port, and at least the force applied to the spool by the action of the signal pressure supplied to the signal pressure input port and the A control valve that adjusts the pressure of the fluid from the supply source side and outputs it from the output port by balancing the force applied to the spool by the action of the pressure of the fluid,
In addition to the control valve, the fluid adjustment unit has a spool movable along the extension direction of the rotation shaft and an electromagnetic unit that generates thrust to move the spool in the extension direction. A robotic device including a linear solenoid valve that supplies the signal pressure to the signal pressure input port of the valve.

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