JP5080207B2 - Actuator device and robot device using the same - Google Patents

Description

  The present invention relates to an actuator device and a robot device using the same, and more particularly to a variable stiffness actuator device and a human-type or animal-type robot device using the same.

  2. Description of the Related Art Conventionally, for example, in a joint drive of a humanoid robot, a rotary actuator that combines an electric motor and a reduction gear using a gear, a hydraulic device, and the like are used. Among these, combinations of an electric motor such as a DC motor and a speed reducer that are easy to downsize and control are widely used.

  Such human-type and animal-type robots may generate a large force continuously, such as holding an object with a hand or maintaining a state in which a heavy object is lifted. In addition, it is important not only to give power, but also to respond flexibly by adjusting the power according to the conditions of the outside world and sometimes removing the power to receive the external force. For example, when considering the action of opening the door, after pulling the door with great force, the arm must be moved without going against the opening trajectory. That is, in order to bring the robot operation closer to humans, it is important to be able to generate a large force continuously, to operate quickly, and to reproduce a relaxed state in which a force that does not resist external force is removed.

As a technology related to a drive mechanism using centrifugal force, a drive motor has been proposed that adjusts the braking force so that the permanent magnet moves in the axial direction by centrifugal force when the rotational speed becomes excessive (for example, Patent Document 1). Further, there has been proposed a speed control mechanism that adjusts the position of the motor rotor by centrifugal force to change the characteristics of the motor itself (for example, Patent Document 2).
JP 2001-8407 (particularly FIG. 6) JP 2004-215454 A

  In the conventional hydraulic system, it is easy to generate a large force continuously, but there is a problem that the operation speed is reduced accordingly. In addition, in the conventional combination of an electric motor and a speed reducer, for example, in an operation in which a load is constantly applied to a joint, such as an operation in which a robot lifts a load, the electric motor is stopped and the efficiency is low. There's a problem. That is, when the same voltage is applied to the electric motor, the maximum current flows in a stationary state where the rotation is stopped, and all the electric power supplied to the electric motor is consumed as heat in the coil, which is very inefficient. In addition, if this state continues when the current is large, the electromagnetic coil of the electric motor may be burned out. In this case, it is conceivable to reduce the load on the electric motor by using a reduction gear with a high reduction ratio, but in the stationary state, all the input power is consumed as heat in the coil, and the joint operating speed Is disadvantageous.

  Further, the conventional apparatus has a problem in that it cannot perform an operation that removes force or flexibly responds to external force. That is, a separate device is required to reproduce the operation of pulling out the force with the hydraulic device, and the larger the generated force of the device, the larger the scale and the bulky. Moreover, in the combination of an electric motor and a speed reducer, it is difficult to move the joint from the outside when a speed reducer with a large reduction ratio is used. In order to avoid this, it is conceivable to use a high-power electric motor or a transmission, but there is a problem that the energy consumption is remarkably increased or the structure becomes complicated and the apparatus is enlarged.

  For example, in a human shoulder joint, a plurality of muscles are curvedly arranged along the joint portion, and the muscles are individually curved and contracted to realize a wide range of movable functions of the shoulder portion. If there is an actuator that reproduces the function of a muscle that is curved and contracted in this way, the degree of freedom of actuator placement will be increased, and it will be possible to faithfully reproduce the movement of human muscles. This is convenient for constructing the robot.

  Furthermore, in order to improve the power utilization rate, even if an electric motor is used to distribute a large amount of power to multiple axes, as in a hydraulic system, the electromagnetic clutch that controls the distribution can transmit only a small torque, and the reduction mechanism Therefore, in terms of weight and space, eventually, the electric motor is arranged on each drive shaft. It would be convenient if there was a system that could distribute the motor's high-speed, small-torque power to multiple axes with a simple configuration and use it with a large torque.

  In view of the above problems, the present invention provides an actuator device that can easily move a joint or the like by an external force when power is stopped, and that does not impair efficiency even when a large load is constantly applied, and a robot device using the actuator device. The purpose is to provide. It is another object of the present invention to provide an actuator and a robot apparatus that can be flexibly arranged so that the actuator can be installed in a curved manner.

  In order to achieve the above object, an actuator device according to an aspect of the present invention is an actuator device that converts rotation of a motor into linear motion, and is a rotation base portion that rotates directly or indirectly connected to the motor. 12 or 15), a sliding base (15 or 16) provided so as to be slidable on the rotation shaft of the rotating base, and one or more weight members (rotating together with the rotating base and movable outward by centrifugal force) 14) and one or more units having a link mechanism (13) for changing the distance between the rotating base and the sliding base using the centrifugal force.

  In one embodiment of the present invention, a plurality of the units are connected on the rotating shaft.

  In the actuator device according to the embodiment in which a plurality of units are continuously provided, it is preferable that the link mechanism is a ranging tong type link mechanism that connects weight members on the opposite side of adjacent units.

  An actuator device according to another aspect of the present invention is an actuator device that converts rotation of a motor into an operation in a substantially linear direction, and is a rotation base (51 or 57) that rotates by being directly or indirectly connected to the motor. ) And a sliding base portion (57) provided such that the distance from the rotation base portion can be changed, one or more weight members (54) that rotate together with the rotation base portion and can move outward by centrifugal force, and the centrifugal A link mechanism (55) that changes the distance between the rotating base and the sliding base using force, and a flexible that connects the rotating base and the sliding base without interfering with the rotation of the weight member and the link mechanism. One or more units having a cover (56) are provided, and they are expanded and contracted in a state where the rotation axes of the rotation base and the sliding base do not necessarily coincide with each other.

  In an actuator device according to another embodiment of the present invention, each unit is connected by a universal joint.

  A further embodiment of the present invention is an actuator device that performs multi-axis driving, and a plurality of actuator devices according to any one of claims 1 to 5 are connected to a single rotary motor for powering them. The present invention relates to an actuator device characterized by being distributed.

  Furthermore, the present invention relates to a robot apparatus in which any one of the actuator apparatuses described above is applied to joint driving.

  In this robot apparatus, it is preferable that a plurality of actuator apparatuses according to any one of claims 1 to 6 are provided in a joint having one or more degrees of freedom of rotation.

  In the actuator device according to the present invention, the weight member is rotated by the rotation of the motor, and the space between the rotating base and the sliding base is narrowed by the centrifugal force and the link mechanism. As a result, a force for pulling the output end in the axial direction is generated. This actuator device has a spring characteristic in which the contraction force increases in proportion to the extension of the actuator, and its rigidity is proportional to the square of the rotational speed. Therefore, even a small electric motor can obtain a large force with a simple mechanism. Further, for example, when this actuator device is used for an operation in which the robot holds an object with the object lifted up, the electric motor maintains high speed rotation and generates tension even when the robot itself is in a stationary state. Therefore, it is possible to generate a large force continuously without burning the electromagnetic coil. Further, even when such a large force is continuously generated, the energy consumed is only for maintaining the rotation of the electric motor, so that there is little energy loss. Further, since it has a spring characteristic mechanically, its movement is flexible, and the actuator itself can absorb an impact or the like, so that the durability of the apparatus or system is improved. Furthermore, when the motor is stopped, it can be easily moved with an external force, and for example, a state in which the force in a humanoid robot is removed can be reproduced. In addition, when an external force exceeding the generated force is received even during power generation, the motor can be operated in accordance with the external force while maintaining the rotation (centrifugal force), that is, in the direction opposite to the traction direction. In addition, since the motor does not stop or reversely rotate, the mechanism is not damaged. Therefore, it is possible to obtain an actuator particularly suitable for the operation required for a humanoid robot.

  Further, in another actuator device according to the present invention, the rotation base and the sliding base are not connected by the shaft member, and the rotation base and the sliding base are formed from the outside without interfering with the rotation of the weight member and the link mechanism. By providing a flexible cover for connecting the actuators, the actuator device itself can be contracted in a curved state. As a result, it can be contracted while being curvedly arranged like human or animal muscles, and the degree of freedom of arrangement and the naturalness of operation can be improved.

  In addition, if a single actuator unit takes a long movable range, the device becomes large. However, if an actuator device is configured by connecting a plurality of small actuator units, the device can be kept small while ensuring a desired movable range. Can do.

  Further, when a plurality of actuator units are connected in series and the weight members are connected by a ranging tong type link mechanism, the amount of contraction for each unit becomes constant and stable operation and output can be obtained.

  On the other hand, when an actuator device is configured by connecting a plurality of actuator units with a universal joint that transmits rotation, the entire actuator unit can be arranged in a freely bent state and contracted along its extending direction. It can be placed along the angle even on irregularly bent parts such as legs and feet, contributing to convenience and space saving.

  Further, when power is distributed to a plurality of actuator devices by a single motor, a plurality of movable parts can be driven by a single motor, and space saving and power saving can be achieved.

  As described above, the robot apparatus according to the present invention employing the actuator can realize an operation close to a human operation, and can perform a natural operation that does not oppose an external force while applying a force. Also, by providing a plurality of actuator devices for joints with one or more degrees of freedom of rotation, it is possible to achieve a fine operation by controlling the actuators and / or both actuators by antagonizing forces. It becomes. This includes, for example, providing one actuator device in each of two rotation directions in a single-axis joint, or using three or more actuator devices in an antagonistic manner in a multi-axis joint such as a shoulder or a hip joint. It is.

  The best mode for carrying out the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a diagram showing a first embodiment of an actuator device according to the present invention. The actuator device 100 according to the present embodiment obtains a contraction operation in the axial direction of the output end 18 using a centrifugal force generated by the rotational output of the electric motor 11. The actuator device 100 is configured by connecting three actuator units 100a to 100c in series. The upstream unit 100 a is directly connected to the electric motor 11, and the downstream unit 100 c is connected to the output end 18. All the units 100a to 100c and the output end 18 are arranged coaxially, and the main shaft 17 passes through them. The electric motor 11 is controlled by a control unit (not shown), and can be adjusted by rotating speed and stopped by an electromagnetic brake in addition to on / off switching.

  The unit 100a will be described. The most upstream rotation base 12 is connected to the output shaft of the electric motor 11 and the main shaft 17, and these rotate integrally with the rotation of the electric motor 11. On the other hand, the sliding base 15 is configured to be slidable with respect to the main shaft 17. Here, the main shaft 17 is used as a spline shaft, or the key / groove structure is used to pass the sliding base 15 through the main shaft 17. The main shaft 17 transmits the rotation to the sliding base 15 and the sliding base 15 is connected to the main shaft 17. Be able to slide freely in the axial direction. However, in this embodiment, since the rotation is transmitted from the rotation base 12 to the sliding base 15 by the link mechanism 13, this spline engagement is not essential, and the main shaft 17 may be a simple round bar. Further, as long as the sliding base 15 is slidable on the main shaft 17, various other configurations may be used. For example, the cross-section of the main shaft 17 is a polygonal shape and the through hole of the sliding base 15 has a corresponding shape. Also good.

  As shown in FIG. 1, the rotation base 12 and the sliding base 15 are connected by a pantograph type link mechanism 13, and a weight member 14 is provided at a bent portion of the link mechanism 13. The link mechanism 13 can freely rotate with respect to any of the rotation base 12, the sliding base 15, and the weight member 14, and is provided symmetrically with respect to the main shaft 17. In the case of the present embodiment, two sets of link mechanisms 13 are provided symmetrically. However, if the configuration has a center of gravity in the cross section (that is, the rotation axis), the cross section is a Mitsubishi type cross section, a cross section having a cross section, or more. It may be.

  The operation of the actuator unit 100a configured as described above will be described. When the electric motor 11 is not rotating, the sliding base 15 is freely slidable within a predetermined range determined by the relationship with other elements. Next, when the electric motor 11 is operated, the rotation base 12 rotates, and accordingly, the link mechanism 13 and the weight member 14 rotate around the main shaft 17. At this time, a centrifugal force proportional to the square of the rotational speed is generated in the weight member 14 and moves in a direction away from the main shaft 17. As a result, the link mechanisms 13a and 13b are pulled in a direction perpendicular to the main shaft 17, and the sliding base 15 moves toward the rotating base 12 to generate a contraction force.

  Next, when paying attention to the unit 100b, the sliding base 15 in the unit 100a can be regarded as the rotation base of the unit 100b. The same applies to the unit 100c. That is, when the motor 11 is operated, the upstream base 15 is rotated, the link mechanism 13 is rotated to generate centrifugal force, and the downstream base 16 is pulled upstream. The sliding base 16 of the unit 100c is rotatably connected to an output end 18 via a bearing 19 such as a bearing, and the output end 18 is rotated by a spline engagement or key / groove structure with the housing 20 of the actuator device. Limited. Thereby, the rotation of the output end 18 is prevented, and only the contraction force in the axial direction can be taken out. The actuator device of the present invention may have a configuration in which only one unit 100 is provided, but the slide distance of the most downstream output end can be increased by connecting a plurality of actuator units in this way. . At this time, if the contraction of each unit becomes uneven because only some of the units are stretched, the overall operation may be impaired. However, since the actuator device of this embodiment has a spring characteristic, a plurality of units are connected. Even so, the shrinkage amount of each unit is made uniform.

  When the output end 18 is fixed or stretched in the extension direction by an external force during the operation of the actuator device, the movement in the contraction direction is hindered, but the motor 11 and the weight member 14 rotate without being obstructed and correspond to the input voltage. Increase the speed to the rotational speed and stabilize. At this time, the contraction force also increases according to the rotation speed, and when the contraction force exceeds the external force, the output end 18 starts moving in the contraction direction.

  The contraction force is proportional to the axial length of the actuator due to the geometric relationship of the link mechanism. It functions as a linear spring in which the contraction force increases as the actuator becomes longer. The rigidity of this spring increases in proportion to the square of the rotational speed. Due to this spring characteristic, the actuator device is almost uniform in the amount of contraction of the individual units as in the case of a plurality of springs connected in series, and does not vary extremely.

  Further, when the output end 18 is pulled from the outside in a state where the rotation speed of the electric motor 11 is stable, the angle of the link mechanism 13 is opened and the rotation radius of the weight member 14 is reduced. Also at this time, since the tangential speed of the rotational movement of the weight member 14 does not substantially change, the weight 14 rotates faster, the centrifugal force increases, and the contraction force acting on the output end 18 in addition to the contraction force due to the original spring characteristics. Will increase. Since the rotational speed returns to the original rotational speed due to friction and the rotation of the electric motor 11 with the passage of time, the contracting force acting on the output end 18 returns to the contracting force due to the original spring characteristics. Therefore, the actuator device acts like a drag force of the oil damper against the external force pulling the output end 18. This drag characteristic can be adjusted by controlling the rotational speed of the electric motor 11.

  In the illustrated actuator device, the link mechanism and the weight member are configured as separate members, but the link mechanism may also serve as the weight member. That is, for example, without providing the weight member 14 as a separate member in the embodiment of FIG. 1, the material, size, weight, etc. of the link mechanism 13 are adjusted and pulled outward by centrifugal force at the time of rotation. The space between the moving bases 15 can be narrowed.

  FIG. 2 is a diagram showing the configuration of the second embodiment of the present invention. In the actuator device according to the present embodiment, the link mechanism 22 that connects the weight members 24 of the adjacent units 200a to 200c is a storage tong type (so-called magic hand-like expansion and contraction bark) that connects the weight members on the opposite side of the adjacent units. It is a link mechanism. That is, the center of each link member 22b is rotatably attached to the sliding base 15, and weight members 24 are provided at both ends thereof. Thereby, the movement of the weight member 24 of each unit 200a-c is interlocked, the contraction amount for each unit becomes constant, and a stable operation and output can be obtained. The elements other than the link mechanism are basically the same as those in the first embodiment shown in FIG.

  FIG. 3 is a diagram showing the configuration of the third embodiment of the present invention. In the actuator of the present embodiment, a bendable hinge member 32 is provided at each end of each weight member 33, and the hinge member 32 connects the rotating base 32 and the sliding base 35. As shown in the sectional view of FIG. 3b, the weight member extends in four directions instead of two directions in the cross section. Even if the actuator device is configured in this way, when the rotation base 31 is rotated by the rotation of the motor, the weight member 33 is rotated around the axis, the centrifugal force acts, and the hinge element 32 is pulled in the direction away from the axis. The contraction motion can be generated.

  FIG. 4 is a diagram showing the configuration of the fourth embodiment of the present invention. The actuator device of the present embodiment realizes a flexible arrangement by connecting individual actuator units 300a to 300c with universal joints. As shown in the figure, the individual units 300a to 300c have a substantially independent configuration, and are connected by a universal joint 41 that transmits rotation. When the electric motor 11 is rotated, the most upstream unit 300a rotates and contracts while rotating the output end provided with the universal joint 41, that is, the sliding base. The universal joint 41 transmits the rotation while pulling the next actuator unit 300b, whereby the weight member of the unit 330b rotates and contracts. If the actuator device is configured in this manner, for example, the device can be arranged at a bent arm or leg of a humanoid robot, and space can be saved. In order to install in a curved portion, it is desirable to cover each unit 300 with a casing or a flexible cover described later so that the rotating elements of the unit do not come into contact with other members.

  FIG. 5 is a diagram showing the configuration of the fifth embodiment of the present invention. The actuator device according to the present embodiment achieves strong protection by a protective cover while enabling a curved arrangement. As shown in a partial cross-sectional view of each actuator unit 500 in FIG. 5B, the rotation base 51 and the sliding base 57 are respectively held on the support plate 53 via bearings 52. One end of the link mechanism 55 is attached to the rotation base 51 via a ball joint, and the other end is rotatably connected to the weight member 54. As a result, the entire actuator mechanism can be bent with respect to the rotation axis direction. As shown in FIG. 5C, the link mechanism 55 of the present embodiment is configured by arranging the weight members 54 in a cross shape, but as described above, this is not an essential configuration. Further, in this embodiment, the rotating base 51 and the sliding base 57 are the same as parts, but are distinguished and referred to for convenience in that the former is connected to power and the latter is connected to the output end.

  On the other hand, the support plates 53 are connected by a plurality of outer shell links 56 in addition to the actuator mechanism. The outer shell link 56 of this embodiment connects the portions of the circular outer periphery of the support plate 53 that are equally divided into eight parts, and each outer shell link 56 has a rotation shaft at the center thereof and swells outward. It is arranged in a letter shape. FIG. 5D shows only the support plate 53 and the outer shell link 56. The outer shell link 56 has a function of protecting the rotating element of the actuator unit while preventing the entire mechanism from contracting, enabling bending in the rotation axis direction. If the outer shell link 56 is covered with a cover made of an elastic body such as rubber or a net-like material such as polymer fiber, the rotating body can be protected more reliably. By connecting a plurality of actuator units 500 configured in this way, an actuator device that can bend and contract freely can be constructed.

  FIG. 6 is a diagram showing the configuration of the sixth embodiment of the present invention. The actuator device of the present embodiment is a modification in which a hinge mechanism is applied to the fifth embodiment shown in FIG. As shown in the sectional view of FIG. 6B, the rotation base 61 and the sliding base 67 are supported by the support plate 63 via bearings 62. A weight member 65 is held between the rotation base 61 and the sliding base 67 by a hinge mechanism 64 arranged in a cross shape as shown in FIG. Since the hinge mechanism 64 serves as a link and allows torsion, the actuator unit can be bent with respect to the rotation axis direction.

  On the other hand, the support plates 63 are connected by a plurality of outer shell hinges 66 in addition to the actuator mechanism. The outer shell hinge 66 of the present embodiment is provided with hinge members that can be bent at important points at equal intervals to protect the rotating element of the actuator unit from being obstructed from the outside and to bend the actuator device. To play a role. As shown in detail in FIGS. 6B and 6D, the outer shell hinge 66 of the present example is configured as a parallel link on the rotating base 61 side. It is devised to move in parallel and not to enter the internal rotation mechanism. If the outer shell hinge 66 is covered with an elastic cover such as rubber or a net material such as polymer fiber, the rotating element can be more reliably protected.

  FIG. 7 is a view showing an embodiment of a robot joint to which the actuator device of the present invention is applied. As shown in this figure, one actuator 300a, 300b is provided in each of two rotational directions of a joint having a single rotational shaft 72, and these are antagonized to drive the joint. Here, both the actuators 300a and 300b may be any of the actuator devices described above, and the number of actuator units included in each actuator device can be appropriately determined in consideration of the installation location and the required stroke.

  FIG. 8 is a diagram showing a further preferred embodiment of the actuator device according to the present invention, which is intended to drive a plurality of actuator devices with one electric motor. As shown in the figure, the power of a single electric motor 11 is distributed to a plurality of actuator devices using a gear mechanism 81 and a universal conductive wire 83. Since each actuator generates force depending on speed, power can be distributed even with an electromagnetic clutch having a small transmission torque.

  FIG. 9 is a view showing a modification of the actuator device according to the present invention. The actuator device of the present embodiment also pushes the weight member outward by centrifugal force by the rotation of the electric motor, and extracts only the force in the contraction direction using this separating force.

  As shown in a sectional view in FIG. 9, a rotation base (main shaft) 91 is connected to the electric motor 11, and a support column 93 is fixed to the rotation base (main shaft) 91. The weight member 95 is slidable on the pillars 93a and 93b, and is normally urged outward by a spring 94. One end of the wire 96 is fixed to the main shaft, and from here through the main shaft and the weight member 95 via the pulley 92, it is finally connected to the output shaft 98. The output shaft 98 is connected to the main shaft 91 with a gradient key 97 or is spline-engaged so that the output shaft 98 can rotate with the main shaft 91 and slide in the axial direction. The output end 99 is rotatably attached to the output shaft 98 by a ball bearing or the like so that only the movement in the contraction direction can be taken out.

  When the output end 99 is pulled in the extending direction while the electric motor 11 is stopped, the weight member 95 is pulled in the direction of the main shaft 91 by the wire, and the entire mechanism is extended. Also in this case, the contraction force by the spring 94 is generated. When the electric motor 11 is rotated in this state, the main shaft 91 and the weight member 94 rotate integrally, and the weight member 95 tends to move outward by centrifugal force, so that the wire 96 is pulled and the output shaft 98 is pulled back. Accordingly, the rotation is canceled by a ball bearing or the like, and only the contraction force is obtained at the output end 99. By changing the arrangement and number of the wires 96 and pulleys 92, desired stroke and contraction force generation characteristics can be adjusted.

  FIG. 10 is a view showing a further modification of the actuator device according to the present invention. In the actuator device according to the present embodiment, the movement of the weight member 103 is not defined by the link mechanism but by the slit plate 102 provided with a guide slit. The slit plate 102a is attached to the rotation base 101 and rotates together therewith. The other slit plate 102 b is fixed to the sliding base 105. The output end 107 is attached to the sliding base 105 via a rotary bearing 106 such as a bearing, and is configured to take out the rotational force and extract only the contraction force. The weight member 103 is engaged with the guide slit of the slit plate 102 by a pin 104. As shown in FIG. 10, the slits of the slit plate 102 are formed such that the distance closer to the rotation axis is narrower and the distance is wider when moving away from the rotation axis.

  When the electric motor 11 starts rotating, the slit plate 102 and the weight member 103 guided thereby also rotate together, and the weight member 103 moves outward by centrifugal force. Accordingly, the interval between the slit plates 102 is narrowed due to the relative relationship between the pin 104 and the slit, and the output end 107 moves in the contraction direction. In the actuator device having this configuration, if the slits of the slit plate 102 are arranged opposite to that shown in FIG. 10, for example, the output end 107 can be moved in the extension direction instead of the contraction direction during rotation. Further, the output characteristics can be adjusted by changing the gradient and curvature of the slit.

  FIG. 11 is a view showing a further modification of the actuator device according to the present invention. The actuator device according to the present embodiment connects a weight member to a rotation shaft, and extracts linear motion by a rack and pinion mechanism using the rotation associated with the movement of the weight member due to centrifugal force. . As shown in the figure, an electric motor 11 is connected to a rotation base 111 (input shaft), and a flat plate 118 having a rotation point symmetrically with respect to the rotation shaft is connected. A gear 114 is attached to the disengagement point, and a weight member 112 is connected from the gear 114 via the shaft 113. These elements are rotated together by the electric motor 11. The gear 114 meshes with a rack shaft 115 that can slide on the rotation shaft. The rack shaft 115 is connected to the output end 117 via a bearing mechanism such as a bearing.

  When the electric motor 11 starts to rotate, the weight member 112 also rotates and spreads in the outer peripheral direction by centrifugal force. Along with this, the gear 114 rotates, the rack shaft 115 is drawn to the rotation base 111 side, and the output end 117 contracts. The generated force with respect to the contraction length at this time has a parabolic characteristic, which is close to the generated force characteristic of the muscle. In addition, when the initial position of the weight member 112 in FIG. 11 is set to the opposite side, the gear 114 can be rotated in reverse to realize the operation in the extending direction.

  As described in detail above, according to the actuator mechanism of the present invention, the weight member is rotated by the rotation of the motor, and the centrifugal force and the link mechanism narrow the space between the rotating base and the sliding base, resulting in the output end. A force is generated that pulls in the axial direction. Since the force obtained by the centrifugal force is proportional to the square of the rotational speed, even a small electric motor can obtain a large force with a simple mechanism. Further, for example, when this actuator device is used for an operation in which the robot holds an object with the object lifted up, the electric motor maintains high speed rotation and generates tension even when the robot itself is in a stationary state. Therefore, it is possible to generate a large force continuously without burning the electromagnetic coil. Further, even when such a large force is continuously generated, the energy consumed is only for maintaining the rotation of the electric motor, so that there is little energy loss. In addition, as the rotational speed increases from zero, for example, the generated force increases in proportion to the square thereof, so that the force does not act suddenly not only on the actuator device but also on various parts to which the mechanism is applied. Therefore, the operation is essentially soft and the durability of the apparatus and system is improved. Furthermore, when the motor is stopped, it can be easily moved with an external force, and for example, a state in which the force in a humanoid robot is removed can be reproduced. In addition, when an external force exceeding the generated force is received even during power generation, the motor can be operated in accordance with the external force while maintaining the rotation (centrifugal force), that is, in the direction opposite to the traction direction. In addition, since the motor does not stop or reversely rotate, the mechanism is not damaged. Therefore, it is possible to obtain an actuator particularly suitable for the operation required for a humanoid robot.

  In addition, this invention is not limited to the form of the said Example, Those skilled in the art can consider various modifications and changes from description of this specification. It should be understood that the scope of the present invention encompasses such modifications and changes, and the extension thereof should be interpreted only by the appended claims.

  The actuator device according to the present invention can be applied to various power mechanisms that require axial contraction or expansion. For example, taking advantage of the feature of the present invention that allows the spring characteristics to be changed electrically, the suspension characteristics can be changed in response to changes in the vehicle conditions and the running surface to keep the vehicle stable. It can be used for necessary automobile and train suspensions and seismic isolation devices that absorb various vibrations quickly.

  In addition, even if a large force is generated, the power consumption is small and the generated force is proportional to the square of the speed, so even a relatively small electric motor can obtain a large generated force continuously. Can be suitably used as power for a brake device that requires a large amount of force or a clamping device that requires a large force continuously.

  In addition, since the force can be released from the external force, it can be used as a power device for automatic doors, preventing excessive tightening even if the door gets caught and improving safety. Can be made.

  Furthermore, the robot apparatus using the actuator device of the present invention can be suitably used in the machine manufacturing industry and the robot industry.

It is a figure which shows the structure of 1st Example of the actuator apparatus concerning this invention. It is a figure which shows the structure of 2nd Example of the actuator apparatus concerning this invention. It is a figure which shows the structure of 3rd Example of the actuator apparatus concerning this invention. It is a figure which shows the structure of 4th Example of the actuator apparatus concerning this invention. It is a figure which shows the structure of 5th Example of the actuator apparatus concerning this invention. It is a figure which shows the structure of 6th Example of the actuator apparatus concerning this invention. It is a figure which shows the structure of 7th Example of the actuator apparatus concerning this invention. It is a figure which shows the structure of 8th Example of the actuator apparatus concerning this invention. It is a figure which shows the structure of 9th Example of the actuator apparatus concerning this invention. It is a figure which shows the structure of 10th Example of the actuator apparatus concerning this invention. It is a figure which shows the structure of 11th Example of the actuator apparatus concerning this invention.

Explanation of symbols

11 Electric motor 12 Rotating base 13 Link mechanism 14 Weight member 15 Sliding base 18 Output end 100, 200, 300 Actuator unit 56 Outer shell link 84 Clutch 94 Spring 96 Wire 102 Slit plate 104 Pin 114 Gear 115 Rack shaft

Claims (4)

An actuator device that converts rotation of a motor into linear motion,
A rotating base (12 or 15) that rotates directly or indirectly connected to a motor, a sliding base (15 or 16) that is slidably provided on a rotating shaft of the rotating base, and rotates together with the rotating base. A plurality of units having one or more weight members (14) movable outward by centrifugal force and a link mechanism (13) for changing the distance between the rotating base and the sliding base using the centrifugal force. An actuator device characterized in that the link mechanism is a ledge tong type link mechanism that connects weight members on opposite sides of adjacent units . An actuator device for multi-axis driving, wherein a plurality of actuator devices according to claim 1 are connected to a single rotary motor and power is distributed to these actuator devices. 3. A robot apparatus, wherein the actuator apparatus according to claim 1 is applied to joint driving. 4. The robot apparatus according to claim 3, wherein a plurality of actuator apparatuses according to claim 1 or 2 are provided at a joint having one or more degrees of freedom of rotation.

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