JP4803462B2 - manipulator - Google Patents

Description

  The present invention relates to a manipulator used for assembly of minute mechanical parts or electronic parts, a manipulator for biological manipulation, position control for observation with a precision microscope, position control for precision measurement, position control for a tool for micromachining, and the like.

  Conventionally, a displacement generating mechanism with a high resolution and good controllability in a very narrow range has been demanded for assembling work of minute parts and minute operations related to biotechnology. In response to this requirement, a hydraulic or electric displacement mechanism is used as a manipulator.

  There are two types of electric displacement mechanisms, which are based on the same principle as general positioning mechanisms, and obtain linear motion by a screw feed mechanism or linear actuator, or directly use rotational motion, but basically have a single degree of freedom. Multi-degree-of-freedom translational displacement is generated at the manipulator tip by stacking mechanisms with For example, Patent Document 1 describes a hydraulic manipulator.

  When rotation of the manipulator tip is required, a rotation mechanism is mounted on the linear motion mechanism or the linear motion mechanism is mounted on the turning mechanism.

  Another method uses a pantograph mechanism. As such a manipulator, for example, Patent Document 2 discloses, for example, a handling unit that grips a minute object by bringing a tip of a gripping finger close thereto, and an XY driving unit that displaces a pantograph mechanism and drives the X and Y directions. , A θz drive unit that changes the posture direction of the handling unit so that the gripping finger swings around the tip of the gripping finger of the handling unit by displacing the pantograph mechanism, and a Z drive unit that drives the handling unit in the Z direction The XY drive unit and the θz drive unit are configured integrally, the Z drive unit is supported by the output link of the pantograph mechanism, and the handling unit is a micromanipulator supported by the Z drive unit. It is disclosed. A manipulator using a parallel link mechanism is disclosed in Patent Document 3, for example.

JP 2001-330781 A JP 2007-030137 A JP 2003-062773 A

  However, in the conventional technology, particularly a micro assembly device, a compact mechanism is required, and the force acting on the manipulator in micro work is very small, but it is the same as the mechanism that handles large displacement and large acting force. A mechanism is used.

  For example, a stack of linear motion or rotational single degree-of-freedom mechanism elements each having a guide mechanism and an actuator is an obstacle to downsizing and cost reduction. Further, the motion error of each mechanism element is accumulated, and it is difficult to obtain the desired motion accuracy at the manipulator tip. Furthermore, it is difficult to reduce the size of a device using a parallel link mechanism as compared with the operating range.

  An object of the present invention is to provide a manipulator having a compact and simple mechanism that gives a small translational displacement in a direction perpendicular to the axis and a rotational displacement around the axis.

In order to solve the above-described problems, the present invention includes an arm unit that performs work, a rotation angle control unit that controls a rotation angle of the arm unit, and a displacement control unit that controls the displacement of the arm unit. In the manipulator, the rotation angle control unit includes a rotation angle application unit that applies a rotational driving force, and the arm unit is connected to the rotation angle application unit and is rotatable and bendable. And a working shaft that is connected to the bending shaft portion and moves when the bending shaft portion is bent, and a working portion that is installed at a tip of the working shaft and performs various operations, and the displacement control portion Comprises a displacement applying means for applying a force to the action shaft, and an output member for transmitting a driving force of the displacement applying means and always abutting on the action shaft.
In addition, the displacement control unit includes an urging unit that applies an urging force that always brings the output member into contact with the action shaft.
Further, the displacement applying means is constituted by a rotation drive motor, and the output member is constituted by a cam having a rotation axis in a direction perpendicular to the action axis.
In addition, the cam has a groove on an outer peripheral surface that is in contact with the action shaft.
Further, the cam has a flange on an outer peripheral surface in contact with the action shaft.
The displacement control unit may include a support spring that applies an urging force so that the operating shaft always contacts the flange.
Further, the displacement applying means is composed of a linear actuator.
The displacement control unit includes a first displacement control unit and a second displacement control unit that applies a force to the action axis in a direction perpendicular to the first displacement control unit.

  According to the manipulator of the present invention, it is possible to generate a high-resolution multi-degree-of-freedom displacement in a minute range. In addition, there is no guide mechanism for each degree of freedom, and the simple structure enables compactness and low cost. Furthermore, the generated displacement of each degree of freedom can be accurately controlled.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a view showing main components constituting the manipulator 1 according to the first embodiment of the present invention. FIG. 1A is a view from the top, and FIG. 1B is a view from the side.

  The manipulator 1 includes an arm unit 2, a rotation angle control unit 3, and a first displacement control unit 4.

  The arm unit 2 is connected to the rotation angle control unit 3, is rotatable, is connected to the bending shaft portion 21 that can be bent, and the bending shaft portion 21. The arm portion 2 is bent by receiving a force from the first displacement control unit 4. It has an action shaft 22 that moves when the shaft portion 21 is bent, and a gripper 23 that is installed at the tip of the action shaft 22 and performs various operations. In addition, what is installed in the front-end | tip of the action shaft 22 is not restricted to the gripper 23, A thing of another structure may be sufficient, and it is preferable when it is set as the structure which can be replaced | exchanged according to the intended purpose.

  The bending shaft portion 21 may be selected from a material that is flexible and has high torsional rigidity. An elastic body may be used. For example, a spring steel material, a shape memory alloy, a fiber-containing synthetic resin, a universal joint, or the like is preferable. Since the action shaft 22 rotates while being in contact with other members, it is preferable that the action shaft 22 has a circular cross section and a smooth surface. The gripper 23 may have a conventionally used structure, but it is desirable that the gripper 23 can be expanded and contracted in the action axis direction.

  The rotation angle control unit 3 includes a rotation angle application motor 31 as a rotation angle application means such as a servo motor or a step motor that applies a rotation drive force, an output shaft 31a that outputs the drive force of the rotation angle application motor 31, and a joint. 32, a rotating shaft 33 that transmits the driving force output from the output shaft 31 a to the arm portion 2, and a bearing 34 that rotatably supports the rotating shaft 33.

  In addition, when transmitting a driving force from the output shaft 31a to the rotating shaft 33, you may transmit indirectly via transmission mechanisms, such as a speed reducer and a link mechanism. The rotating shaft 33 preferably has high bending rigidity.

  The first displacement control unit 4 outputs a first displacement applying motor 41 as a first displacement applying means such as a servo motor or a step motor for applying a driving force, and a driving force of the first displacement applying motor 41, and a working shaft A first cam 42 as a first output member that has a rotating shaft in a direction perpendicular to 22 and always contacts the working shaft 22, and a first biasing means that biases the working shaft 22 toward the first cam 42. As a first preload spring 43.

  Next, the operation of the manipulator 1 of the first embodiment will be described. First, an operation for rotating the gripper 23 will be described. In order to rotate the gripper 23, the rotation angle giving motor 31 may be operated. By operating the rotation angle application motor 31 to a desired angle, the gripper 23 rotates to a desired angle via the output shaft 31a, the joint 32, the rotation shaft 33, the bending shaft portion 21, and the action shaft 22.

  Next, an operation for displacing the gripper 23 will be described. FIG. 2 is a diagram illustrating a state in which the action shaft 22 is displaced. In order to displace the gripper 23 in the Y direction, the first displacement applying motor 41 is operated to rotate the first cam 42. When the first cam 42 rotates, the contact point P between the first cam 42 and the action shaft 22 is displaced in the Y direction, the action shaft 22 is inclined from the bending point 21a of the bending shaft portion 21, and the gripper 23 is moved in the Y direction. Displace. The gripper 23 at the tip of the action shaft 22 is displaced with the movement distance of the contact point P between the first cam 42 and the action shaft 22 being enlarged by the lever ratio B / A. Since the displacement of the gripper 23 is uniquely determined by the curved shape and the rotation angle of the first cam 42, the displacement of the gripper 23 can be precisely controlled by precisely controlling the rotation angle of the first cam 42. .

  When the rotation angle imparting motor 31 is operated with the gripper 23 displaced as shown in FIG. 2, the bending shaft portion 21 can rotate without changing the bending direction. It is possible to rotate with. That is, the rotation and displacement of the gripper 23 can be applied independently without interference.

  3 and 4 are views showing a structure for restraining the displacement of the action shaft 22 in the X direction.

  3A is a view seen from the direction of the action axis, and FIG. 3B is a view seen from the side. In the structure of FIG. 3, a flange 42 a is provided on one side of the circumferential surface of the first cam 42, and pressed against the flange 42 a side by a support spring 44 from the other side in a state in which the circumferential surface is in contact with the action shaft 22. . Alternatively, the first preload spring 43 may be installed in an inclined state, and the action shaft 22 may be pressed against both the circumferential surface of the first cam 42 and the flange 42a only by the first preload spring 43.

  4A is a view seen from the direction of the action axis, and FIG. 4B is a view seen from the side. In the structure of FIG. 4, a groove 42 b is provided on the circumferential surface of the first cam 42, the action shaft 22 is disposed in the groove 42 b having an arcuate cross section, and the action shaft 22 is attached to the first cam 42 by a first preload spring 43. It is structured to be pressed against the circumferential surface. As shown in FIG. 5, the groove 42b may have a V-shaped cross section.

  FIG. 6 is a diagram showing a structure using the first linear actuator 141 as the first displacement applying means. The first linear actuator 141 is preferably disposed so as to abut against the action shaft 22 from the X direction via the first output member and be displaced in the X direction. As the first linear actuator 141, an electric micrometer head or a piezoelectric actuator is preferably used. The first output member may be a part of the first linear actuator 141 or may be a separate body.

  Next, an embodiment in which the gripper 23 is movable in a plane orthogonal to the action shaft 22 will be described. FIG. 7 is a view showing main components constituting the manipulator 1 according to the second embodiment of the present invention, and FIG. 8 is an enlarged view of the first displacement control unit 4 and the second displacement control unit 5.

  FIG. 7A is a view from the top, and FIG. 7B is a view from the side. As shown in FIG. 7, the manipulator 1 according to the second embodiment has a structure in which a second displacement control unit 5 is added to the first embodiment.

  Similar to the first displacement control unit 4, the second displacement control unit 5 includes a second displacement applying motor 51 as a second displacement applying unit such as a servo motor or a step motor for applying a driving force, and a second displacement applying motor. The second cam 52 as a second output member that outputs a driving force 51 and has a rotation axis in a direction perpendicular to the action shaft 22 and abuts on the action shaft 22, and the action shaft 22 on the second cam 52 side. And a second preload spring 53 as a second urging means for urging the power.

  Since other structures are the same as those in the first embodiment, description thereof is omitted.

  Next, the operation of the manipulator 1 of the second embodiment will be described. First, an operation for rotating the gripper 23 will be described. In order to rotate the gripper 23, the rotation angle giving motor 31 may be operated. By operating the rotation angle application motor 31 to a desired angle, the gripper 23 rotates to a desired angle via the output shaft 31a, the joint 32, the rotation shaft 33, the bending shaft portion 21, and the action shaft 22.

  Next, an operation for displacing the gripper 23 will be described. In order to displace the gripper 23 in the Y direction, the first displacement applying motor 41 is operated to rotate the first cam 42. When the first cam 42 rotates, the first contact point P between the first cam 42 and the action shaft 22 is displaced in the Y direction, the action shaft 22 is inclined from the bending point 21a of the bending shaft portion 21, and the gripper 23 is Displace in the direction. In order to displace the gripper 23 in the X direction, the second displacement applying motor 51 is operated to rotate the second cam 52. When the second cam 52 rotates, the second contact point Q between the second cam 52 and the action shaft 22 is displaced in the X direction, the action shaft 22 is inclined from the bending point 21a of the bending shaft portion 21, and the gripper 23 is X Displace in the direction. Further, in order to displace the gripper 23 in the XY plane, the displacement in the X direction and the displacement in the Y direction may be performed simultaneously.

  Since the displacement of the gripper 23 is uniquely determined by the curved shape and the rotation angle of the first cam 42 and the second cam 52, the gripper 23 is controlled by precisely controlling the rotation angle of the first cam 42 and the second cam 52. Can be controlled precisely.

  When the rotation angle giving motor 31 is operated with the gripper 23 displaced, the bending shaft portion 21 can rotate without changing the bending direction, so that the gripper 23 can rotate at the displaced position. It is. That is, the rotation and displacement of the gripper 23 can be applied independently without interference.

  In the present embodiment, the first preload spring 43 presses the action shaft 22 against the circumferential surface of the first cam 42, and the second preload spring 53 presses the action shaft 22 against the circumferential surface of the second cam 52. The shaft 22 can be moved to a desired displacement without shaking. As shown in FIG. 9, the first preload spring 43 or the second preload spring 53 is inclined and installed, and only one of the first preload spring 43 or the second preload spring 53 is used to move the working shaft 22 to the first position. It is good also as a structure pressed against both the surrounding surfaces of the 1 cam 42 and the 2nd cam 52. FIG. Further, the first preload spring 43 and the second preload spring 53 may not be installed, and another preload spring may be installed at any position.

  FIG. 10 is a diagram showing a structure using the first linear actuator 141 and the second linear actuator 151 as the first displacement applying unit and the second displacement applying unit. FIG. 10A is a view as seen from above, and FIG. 10B is an enlarged view of the vicinity of the first linear motion actuator 141 and the second linear motion actuator 151 as seen from the direction of the action axis.

  The first linear actuator 141 abuts the action shaft 22 from the X direction perpendicular to the action shaft 22 via the first output member, and is displaced in the X direction. It is preferable that they are arranged so as to contact each other through the second output member from the vertical Y direction and be displaced in the Y direction. As the first linear actuator 141 and the second linear actuator 151, it is preferable to use an electric micrometer head or a piezoelectric actuator. Further, the first output member may be a part of the first linear actuator 141 or a separate body, and the second output member may be a part of the second linear actuator 151 or a separate body. It may be.

  According to the manipulator of the present embodiment, it is possible to generate a high resolution multi-degree-of-freedom displacement in a minute range. In addition, there is no guide mechanism for each degree of freedom, and the simple structure enables compactness and low cost. Furthermore, the generated displacement of each degree of freedom can be accurately controlled.

  It can be used for assembly of minute mechanism parts or electronic parts, biological manipulators, position control for precision microscope observation, position control for precision measurement, or position control of tools for micromachining, etc., and high resolution in a minute range It is possible to generate multi-degree-of-freedom displacement, and it is possible to reduce the size and price because of a simple configuration, and it is possible to accurately control the generated displacement of each degree of freedom.

It is the figure which showed the manipulator which concerns on 1st Embodiment. It is a figure which shows the state which displaced the action shaft. It is a figure which shows the structure which restrains the displacement of the X direction of an action shaft. It is a figure which shows the structure which restrains the displacement of the X direction of an action shaft. It is a figure which shows the structure which restrains the displacement of the X direction of an action shaft. It is a figure which shows the structure using a linear motion actuator. It is the figure which showed the manipulator which concerns on 2nd Embodiment. It is the figure which expanded the 1st displacement control part and the 2nd displacement control part. It is the figure which expanded the 1st displacement control part and the 2nd displacement control part. It is a figure which shows the structure using the 1st linear motion actuator and the 2nd linear motion actuator.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Manipulator, 2 ... Arm part, 21 ... Bending shaft part, 22 ... Action axis, 23 ... Gripper (working part), 3 ... Rotation angle control part, 31 ... Rotation angle provision motor (rotation angle provision means), 31a ... Output shaft 32... Joint 33. Rotating shaft 34. Bearing 4. First displacement control unit 41. First displacement applying motor (first displacement applying means) 42. First cam (first output member) 43 ... first preload spring (first biasing means), 44 ... support spring, 5 ... second displacement control unit, 51 ... second displacement imparting motor (second displacement imparting means), 52 ... second cam (second 2 output members), 53 ... second preload spring (second biasing means), 141 ... first linear motion actuator (first displacement applying means), 151 ... second linear motion actuator (second displacement applying means)

Claims (8)

In a manipulator comprising: an arm unit that performs work; a rotation angle control unit that controls a rotation angle of the arm unit; and a displacement control unit that controls the displacement of the arm unit.
The rotation angle control unit has a rotation angle applying means for applying a rotation driving force,
The arm portion is connected to the rotation angle providing means and is rotatable and bendable, and a bending shaft portion that is bendable, and an action shaft that is connected to the bending shaft portion and moves when the bending shaft portion is bent. And a working unit that is installed at the tip of the working shaft and performs various operations,
The displacement control unit includes: a displacement applying unit that applies a force to the action shaft; and an output member that transmits a driving force of the displacement applying unit and always contacts the action shaft.   2. The manipulator according to claim 1, wherein the displacement control unit includes an urging unit that applies an urging force that always causes the output member to abut against the action shaft. 3.   3. The manipulator according to claim 1, wherein the displacement applying unit includes a rotation drive motor, and the output member includes a cam having a rotation axis in a direction perpendicular to the operation axis.   The manipulator according to claim 3, wherein the cam has a groove on an outer peripheral surface that abuts on the action shaft.   The manipulator according to claim 3, wherein the cam has a flange on an outer peripheral surface in contact with the action shaft.   The manipulator according to claim 5, wherein the displacement control unit includes a support spring that applies a biasing force so that the working shaft always abuts on the flange.   The manipulator according to claim 1, wherein the displacement imparting unit includes a linear motion actuator.   The said displacement control part has a 1st displacement control part and a 2nd displacement control part which provides force to the direction perpendicular | vertical to the said 1st displacement control part with respect to the said action axis. The manipulator according to claim 7.

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