JP6692626B2 - Working device using parallel link mechanism - Google Patents

Description

  The present invention relates to a working device using a parallel link mechanism which is used in equipment that requires a wide operating range with high speed and high accuracy, such as medical equipment and industrial equipment.

  Patent Documents 1 and 2 propose a parallel link mechanism and a link actuating device used for various working devices such as medical equipment and industrial equipment.

JP, 2000-094245, A US Pat. No. 5,893,296

  The parallel link mechanism of Patent Document 1 has a relatively simple structure, but the operating angle of each link is small. Therefore, if the operating range of the traveling plate is set to be large, the link length becomes long, and the size of the entire mechanism becomes large, which causes the size of the device to increase. There is also a problem that the rigidity of the entire mechanism is low, and the weight of the tool mounted on the traveling plate, that is, the weight that can be carried on the traveling plate is small.

  The link actuating device of Patent Document 2 is a parallel link mechanism in which a distal end side link hub is connected to a proximal end side link hub via three or more sets of four-bar linkages so that the posture can be changed. Is used. As a result, it is possible to operate in a wide operating range with high speed and high accuracy while being compact.

  However, since the link actuating device of Patent Document 2 is a mechanism having two degrees of freedom, the link actuating device alone can be applied to a plurality of side surfaces of a cube or a rectangular parallelepiped, or a three-dimensional work object such as a spherical surface of a sphere. You cannot work on it. When performing work on a three-dimensional workpiece, it is usually necessary to add a mechanism having two or more degrees of freedom to the link actuator so that the total number of degrees of freedom is four or more.

  An object of the present invention is to use a parallel link mechanism capable of working on a three-dimensional work piece while having a structure in which a linear motion mechanism having one degree of freedom is added to a link actuator having two degrees of freedom. It is to provide a device.

  A work device using a parallel link mechanism of the present invention is a work device that performs work in a contact state or a non-contact state with a work body, and the posture of the work body or the work body can be changed. A parallel link mechanism that supports the parallel link mechanism, an attitude control actuator that operates the parallel link mechanism, and a linear motion mechanism that relatively moves the work piece and the work piece in one axial direction.

  The parallel link mechanism connects the distal end side link hub to the proximal end side link hub via three or more sets of link mechanisms so that the posture can be changed, and each of the link mechanisms is connected to the proximal end side link hub. One end is rotatably connected to the link hub and the tip-side link hub, and the other is the end link member on the base end side and the tip end side. A center link member rotatably connected is provided, and the link hub on the tip end side is provided with one of the work subject and the work subject whose posture is changed.

  The attitude control actuator is provided in two or more sets of link mechanisms out of the three or more sets of link mechanisms so as to arbitrarily change the attitude of the distal end side link hub with respect to the proximal end side link hub. ing.

  The linear motion mechanism relatively moves the work piece and the work piece coaxially or in parallel with the central axis of the base end side link hub. The "center axis of the link hub" means the center axis of each rotational pair of the link hub and the end link member, and the center axis of each rotational pair of the end link member and the central link member, respectively. When this point is referred to as the "spherical link center" of the link hub, it means a straight line that passes through this spherical link center and intersects the center axis of the rotational pair of the link hub and the end link member at a right angle.

  A portion of the work piece to be operated by the work body is located in an internal space between the base end side link hub and the tip end side link hub, and the base end side link hub and A bottom surface, which is a surface of the outer surface of the work piece opposite to the work piece from the spherical link center of the one of the link hubs on which the work piece is provided, of the distal end side link hubs. Is more than 1/2 of the distance between the spherical link centers of the link hub on the base end side and the link hub on the tip end side.

  The parallel link mechanism includes a base end side link hub, a front end side link hub, and three or more sets of link mechanisms, and the front end side link hub rotates about two axes orthogonal to the base end side link hub. Configure a free 2-DOF mechanism. Although the two-degree-of-freedom mechanism is compact, the movable range of the distal end side link hub can be widened. For example, the maximum bending angle between the center axis of the link hub on the proximal side and the center axis of the link hub on the distal side is about ± 90 °, and the turning angle of the link hub on the distal side with respect to the link hub on the proximal side is It can be set in the range of 0 ° to 360 °.

  A working device using this parallel link mechanism has a total of three degrees of freedom, which is two degrees of freedom of the parallel link mechanism and one degree of freedom of the linear motion mechanism. Even with the three-degree-of-freedom configuration, the portion of the work piece to be worked by the work piece is positioned in the internal space between the base end side link hub and the tip end side link hub, and the work piece is The work is performed in the internal space. In addition to this, the distance from the spherical link center of the link hub on which the work piece is installed to the bottom surface of the work piece is the distance between the center of each spherical link of the base end side link hub and the tip end side link hub. It is set to 1/2 or more.

  As a result, the posture control actuator operates the parallel link mechanism to change the posture of the work body or the work body, and the linear motion mechanism relatively moves the work body and the work body in the uniaxial direction. Thus, it is possible to perform work in a contacting state or a non-contacting state with the work body on each surface of the work body except the bottom surface. Since it has a three-degree-of-freedom structure, it can be made more compact than the conventional four-degree-of-freedom structure. Further, since the posture of the work piece can be changed at high speed and with high precision by the parallel link mechanism, high speed and high precision work can be performed.

The reason why the work body can work on each surface other than the bottom surface of the work body even with the configuration having three degrees of freedom will be described.
The distance between the spherical link centers of the proximal end link hub and the distal end side link hub is L, and the bending angle that is the angle formed by the central axis of the proximal end side link hub and the distal end side link hub is When θ is set, the distance x between the intersection of the central axes of the proximal and distal side link hubs and the center of each spherical link is x = L / (2cos (θ / 2)). The distance x increases as the bending angle θ increases. Therefore, when the distance T from the spherical link center of the link hub on which the work piece is provided to the bottom surface of the work piece is T ≦ L / 2, the work piece as the bending angle θ increases. The position of the bottom surface moves in a direction away from the central axis of the link hub on which the work piece is not provided. When the position of the bottom surface of the work piece is far away from the central axis, the side surfaces of the work piece having a three-dimensional shape such as a plurality of side surfaces of a cube or a rectangular parallelepiped, a side surface of a cylindrical member, or a spherical surface of a sphere can reach the bottom surface position. You cannot approach the working body.

  On the other hand, when T> L / 2, even if the bending angle θ changes, there is always a posture that satisfies T> L / (2cos (θ / 2)). The work body can approach the side. Therefore, even with the configuration having three degrees of freedom, it is possible to perform work in a contact state or a non-contact state with respect to the side surface of the three-dimensionally shaped work body.

  Further, if the portion of the work piece to be worked by the work piece is located in the internal space between the proximal end side link hub and the distal end side link hub, the work piece is Work is performed in the internal space. In this case, as compared with the case where the work is performed outside the internal space, the center of gravity of the work body or the work body provided on the distal end side link hub is at the base end side and the front end side, which are the rotation centers of the parallel link mechanism. It is close to the intersection of the center axes of the link hubs. Therefore, the moment of inertia of the work body or the work body is small, and even when the heavy work body or the work body is provided on the distal end side link hub, high speed operation is possible. Further, it is possible to reduce the output of the posture changing actuator, save energy, and make the actuator compact.

  In the present invention, the center axis of the link hub of the proximal end side link hub and the distal end side link hub on which the work piece is provided passes through at least a part of the work piece, and the other link The central axis of the hub may coincide with the central axis of the working unit, which is a portion of the working body that works on the work piece. With this configuration, it is possible to work on the work piece from a plurality of directions, the area where the central axis of the working portion of the work piece intersects the side surface of the work piece is increased, and the work range is widened. Further, the relational expression for calculating the positions of the work body and the work body has a relatively simple form, and the control of the attitude control actuator and the linear motion mechanism becomes easy.

In the present invention, the distance from the spherical link center of the link hub of the proximal end side and the distal end side of the link hub on which the work piece is provided to the bottom surface of the work piece is T. , L is the distance between the spherical link center of the proximal end side link hub and the spherical link center of the distal end side link hub, and the distance between the proximal end side in the state where the parallel link mechanism operates up to the maximum operable range. When the maximum bending angle that is an angle formed by the center axis of the link hub and the center axis of the link hub on the tip side is θmax,
T ≧ L / (2cos (θmax / 2))
It is good if the relationship of is established.

  When the parallel link mechanism operates up to the maximum operable range, the distance from the center of the spherical link on the distal side or the proximal side to the intersection of the central axes of the distal or proximal side link hubs is L / (2cos (θmax / 2)). If the distance T is set to L / (2cos (θmax / 2)) or more, the area where the central axis of the working portion of the working body intersects the side surface of the working body increases within the working range of the maximum bending angle θmax. The work range becomes wider.

In the present invention, the maximum distance from the central axis of the link hub of the proximal end side link hub and the distal end side link hub on which the workpiece is provided to the outer peripheral surface of the workpiece is M R is the radius of an inner surface orbital circle that is a circle connecting the central portions of the inner side surfaces of the central link members, and T is the distance from the spherical link center of the distal end side link hub to the bottom surface of the work piece. When the maximum bending angle, which is an angle formed by the central axis of the proximal end side link hub and the central axis of the distal end side link hub in a state in which the parallel link mechanism operates up to the maximum operable range, is θmax ,
R ≧ T ・ sin (θmax / 2) + M
It is good if the relationship of is established. Here, the “inner side surface” of the central link member is a surface that faces a midpoint of a straight line that connects the spherical link centers on the proximal end side and the distal end side.

  By configuring each link mechanism of the parallel link mechanism in this way, it is possible to avoid the work body and the work body from interfering with the central link member. As a result, the movable range and working range of the parallel link mechanism can be widened.

  In the present invention, it is preferable that the work body is provided on the distal end side link hub, the linear motion mechanism is installed on the base end side link hub, and the linear motion mechanism moves the working body. For example, in operations such as liquid application, painting, and processing, the work body is often bulkier and heavier than the work body. With this configuration, the load on the posture changing actuator can be reduced by providing the link hub on the proximal end side with a work piece having a bulk and mass larger than that of the work piece. As a result, the working device can be made compact and the cost can be reduced.

  In the case of the above configuration, it is preferable that the parallel link mechanism is installed so that the link hub on the tip side faces downward, and the orthogonal biaxial linear motion mechanism is arranged above the parallel link mechanism. As a result, the posture control actuator, the control device such as the linear motion mechanism, and the work body are not arranged below the work body. Therefore, it is possible to prevent chips and the like generated from the work piece, grease, paint, etc. attached to the work piece from adhering to and adversely affecting the control equipment and the work piece.

  In the present invention, the work body is provided on the distal end side link hub, the work body is installed on a pedestal serving as a fixed portion, and the entire parallel link mechanism is moved by the linear motion mechanism, It is advisable to move the work body and the work body relatively in one axial direction. In this case as well, similarly to the above, by providing a work body having a bulk and mass larger than that of the work body on the base end side link hub, the load of the posture changing actuator can be reduced. As a result, the working device can be made compact and the cost can be reduced.

  In the present invention, the work piece is rotated around an axis orthogonal to the central axis of the link hub of the base end side and the tip end side link hub on which the work piece is provided. A rotating mechanism may be provided. In this case, the parallel link mechanism has two degrees of freedom, the linear movement mechanism has one degree of freedom, and the rotation mechanism has one degree of freedom, so that a total of four degrees of freedom are configured. A linear motion mechanism is added to the two-degree-of-freedom structure such as the link actuating device of the above-mentioned Patent Document 2, and a three-dimensional object such as a plurality of side surfaces of a cube or a rectangular parallelepiped, a side surface of a cylindrical body, a spherical surface of a sphere, or the like is used. It is necessary to add three or more linear motion mechanisms in order to perform work on the entire circumferential surface of the work body (six surfaces in the case of a cube or a rectangular parallelepiped). That is, the mechanism has five or more degrees of freedom.

  According to this configuration, by adding one linear motion mechanism and one rotation mechanism, the rotation mechanism rotates the work piece, and thus the entire peripheral surface of the work piece is formed. Can work against. When the center of rotation of the work piece by the rotating mechanism is an axis orthogonal to the center axis of the link hub of the base end side link hub and the tip end side link hub on which the work piece is provided, The relational expression for calculating the work position of the work piece by means of becomes relatively simple, and the control of the attitude control actuator and the linear motion mechanism becomes easy.

  When the rotating mechanism is provided, one end is fixed to the link hub on which the work piece is provided among the link hub on the base end side and the link hub on the tip end side, and the other end is a space outside the internal space. The rotating mechanism is installed at the other end of the rotating mechanism fixing member extending to the external space, and the workpiece fixing member is installed on the output shaft of the rotating mechanism. It is preferable that the work body is inserted into the internal space through a space between two adjacent sets of the link mechanisms of one set or more and the work body is installed at the tip of the work body fixing member.

  In this way, by disposing the rotating mechanism in the external space of the parallel link mechanism having a sufficient space, it is possible to prevent the link mechanism from interfering with the rotating mechanism and realize a wider operating range.

A work device using a parallel link mechanism of the present invention is a work device that performs work in a contact state or a non-contact state with a work body, and the posture of the work body or the work body can be changed. The parallel link mechanism that supports the parallel link mechanism, the posture control actuator that operates the parallel link mechanism, and the linear motion mechanism that relatively moves the work body and the work body in the uniaxial direction. The mechanism connects the link hub on the distal end side to the link hub on the proximal end side so that the posture can be changed via three or more sets of link mechanisms, and each of the link mechanisms includes a link hub on the proximal end side and a link hub on the proximal end side. One end is rotatably connected to the tip-side link hub, and the other end link members are at the base end side and the tip end side. A center link member that is rotatably connected, and the link hub on the distal end side is provided with one of the work body and the work body whose posture is to be changed. as to arbitrarily change the attitude of the distal end side link hub relative end side link hub, provided in two or more sets of linkage among the three or more sets of link mechanisms, the parallel link mechanism, the group With the end-side link hub, the tip-side link hub, and the three or more sets of link mechanisms, the tip-side link hub is rotatable about two orthogonal axes with respect to the base-end-side link hub. configure the flexibility mechanism, before Symbol translation mechanism, the center axis of each revolute pair of the proximal and distal link hub and the proximal and distal side end link member, and the proximal-side And the tip end phosphorus A point at which the central axes of the respective rotational pairs of the member and the central link member intersect each other is referred to as a spherical link center of the base hub on the proximal side and the distal side, and the spherical link centers on the proximal side and the distal side are referred to. When a straight line that intersects at right angles with the central axes of the rotation pairs of the proximal side and distal side link hubs and the proximal side and distal side end link members is referred to as the central axes of the proximal side and distal side link hubs, A portion for moving the work piece and the work piece relative to each other coaxially or in parallel with the center axis of the link hub on the base end side, and a part of the work piece that is worked by the work piece. Is located in an internal space between the proximal end side link hub and the distal end side link hub, and is provided with the work piece of the proximal end side link hub and the distal end side link hub. Link hub The distance from the center of the spherical link to the bottom surface, which is the surface of the outer surface of the work object that is located on the opposite side to the work body, is the distance between the base end side link hub and the tip end side link hub. Since the distance between the centers of the spherical links is ½ or more, if the work piece is relatively small, the link actuator having 2 degrees of freedom has a structure in which only a linear motion mechanism having 1 degree of freedom is added, but 3 It is possible to work on a three-dimensional object .

The present invention will be understood more clearly from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are for illustration and description purposes only, and should not be used to define the scope of the present invention. The scope of the invention is defined by the appended claims. In the accompanying drawings, the same part number in a plurality of drawings indicates the same or corresponding part.
It is a front view of one state of the working device concerning a 1st embodiment of this invention. It is a front view of the same working apparatus in a different state. It is the front view which abbreviate | omitted a part of link actuating device of the same working device. It is a perspective view of one state of the link operating device. It is a perspective view of the link operating device in a different state. (A) is a cross-sectional view of a link hub on the proximal end side of the link actuating device, an end link member on the proximal end side, etc., and (B) is a partially enlarged view thereof. It is the figure which expressed one link mechanism of the same parallel link mechanism with a straight line. (A), (B) is a top view of a mutually different to-be-processed body. (A) is a plan view of a work body, and (B) is a front view thereof. (A) is a plan view of a different work body, (B) is a front view thereof. It is explanatory drawing which shows the working operation of the same working apparatus. It is a front view of the working device concerning a 2nd embodiment of this invention. It is a front view of the working device concerning a 3rd embodiment of this invention. It is a front view of the working device concerning a 4th embodiment of this invention. It is a front view of the working device concerning a 5th embodiment of this invention. It is a front view of one state of the working device concerning a 6th embodiment of this invention. It is a front view of the same working apparatus in a different state. It is a front view of the working device concerning a 7th embodiment of this invention. It is a front view of the working device concerning an 8th embodiment of this invention. It is a front view of the working device concerning a 9th embodiment of this invention.

  A working device using a parallel link mechanism according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2 are front views showing different states of the working device. The work device 1 is a device for performing work on the work body 2 by the work body 3. A horizontal base member 6 is built on the base 4 and supported by a plurality of columns 5, a link actuator 7 is installed on the base member 6, and a linear motion mechanism 8 is installed on the base 4. Has been done. The link actuating device 7 includes a parallel link mechanism 9 that supports the work piece 2 in a posture changeable manner, and an attitude control actuator 10 that operates the parallel link mechanism 9. The linear motion mechanism 8 is a mechanism that moves the work body 3 in one axis direction with respect to the work body 2.

  FIG. 3 is a front view of the link operating device, and FIGS. 4 and 5 are perspective views showing different states of the link operating device. The parallel link mechanism 9 of the link actuating device 7 is formed by connecting the distal end side link hub 13 to the proximal end side link hub 12 via three sets of link mechanisms 14 so that the posture can be changed. Note that only one set of link mechanisms 14 is shown in FIG. The number of link mechanisms 14 may be four or more.

  Each link mechanism 14 is composed of an end link member 15 on the base end side, an end link member 16 on the tip end side, and a center link member 17, and forms a four-bar linkage chain mechanism composed of four rotating pairs. The end link members 15 and 16 on the base end side and the tip end side are L-shaped, and one ends thereof are rotatably connected to the link hub 12 on the base end side and the link hub 13 on the tip end side, respectively. The center link member 17 is rotatably connected at its opposite ends to the other ends of the end link members 15 and 16 on the base end side and the tip end side, respectively.

  The parallel link mechanism 9 has a structure in which two spherical link mechanisms are combined. The center axes of the rotational pairs of the proximal end side link hub 12 and the proximal end side end link member 15 and the rotational pairs of the proximal end side end link member 15 and the central link member 17 are They intersect at the spherical link center PA (FIG. 3). Similarly, the center axes of the rotational pairs of the distal end side link hub 13 and the distal end side end link member 16 and the rotational pairs of the distal end side end link member 16 and the central link member 17 are spherical surfaces on the distal end side. They intersect at the link center PB (Fig. 3).

  Further, the distances between the rotational pairs of the proximal end side link hub 12 and the proximal end side end link member 15 and the proximal end side spherical link center PA are the same, and the proximal end side end link member 15 is the same. Also, the distance between each rotational pair of the central link member 17 and the spherical link center PA on the base end side is the same. Similarly, the distances between the rotational pairs of the tip-side link hub 13 and the tip-side end link member 16 and the tip-side spherical link center PB are the same, and the tip-side end link member 16 and the center link are the same. The distance between each rotational pair of the member 17 and the spherical link center PB on the tip side is also the same. The central axes of the rotating pairs of the end link members 15 and 16 on the proximal end side and the distal end side and the central link member 17 may have a certain intersection angle γ (FIG. 3) or may be parallel to each other. Good.

  6A is a cross-sectional view of the base end side link hub 12, the base end side end link member 15, and the like, and FIG. 6B is an enlarged view of FIG. 6A. FIG. 6A shows the relationship between the center axis O1 of each rotational pair of the proximal end side link hub 12 and the proximal end side end link member 15 and the spherical link center PA. The shape and positional relationship of the tip-side link hub 13 and the tip-side end link member 16 are similar to those in FIGS. 6A and 6B (not shown). In FIG. 6A, the central axis O1 of each rotational pair of the base end side link hub 12 and the base end side end link member 15, the base end side end link member 15, and the center link member 17 are shown. The angle α formed by the central axis O2 of each rotation pair is 90 °. However, the angle α may be other than 90 °.

  The three sets of link mechanisms 14 have the same geometrical shape. The geometrically identical shape is represented by a geometric model in which each link member 15, 16, 17 is represented by a straight line, that is, each rotational pair and a straight line connecting these rotational pairs, as shown in FIG. It is said that the model has a shape in which the base end side portion and the tip end side portion with respect to the center portion of the center link member 17 are symmetrical. FIG. 7 is a diagram in which the set of link mechanisms 14 is represented by a straight line. The parallel link mechanism 9 of this embodiment is a rotationally symmetric type, and includes a proximal end side link hub 12 and a proximal end side end link member 15, and a distal end side link hub 13 and a distal end side end link member 16. The positional relationship is rotationally symmetrical with respect to the center line C of the center link member 17. The central portion of each central link member 17 is located on a common orbital circle D.

  With the link hub 12 on the base end side, the link hub 13 on the tip end side, and the three sets of link mechanisms 14, the link hub 13 on the tip end side is orthogonal to the link hub 12 on the base end side, and is freely rotatable about two axes. The degree mechanism is configured. In other words, it is a mechanism in which the link hub 13 on the tip end side can change its posture with two degrees of freedom in rotation with respect to the link hub 12 on the base end side. Although the two-degree-of-freedom mechanism is compact, the movable range of the distal end side link hub 13 with respect to the proximal end side link hub 12 can be widened.

  For example, through the spherical link centers PA and PB on the base end side and the front end side, the respective rotation pairs of the link hubs 12 and 13 on the base end side and the front end side and the end link members 15 and 16 on the base end side and the front end side. When a straight line that intersects the central axis O1 (FIG. 6) at a right angle is used as the central axes QA and QB of the proximal and distal side link hubs 12 and 13, the central axis QA of the proximal side link hub 12 and the distal side are The maximum value of the bending angle θ (FIG. 7) with the central axis QB of the link hub 13 can be about ± 90 °. Further, the turning angle φ (FIG. 7) of the distal end side link hub 13 with respect to the proximal end side link hub 12 can be set in the range of 0 ° to 360 °. The bending angle θ is a vertical angle at which the central axis QB of the distal end side link hub 13 is inclined with respect to the central axis QA of the proximal end side link hub 12. On the other hand, the turning angle φ is a horizontal angle at which the central axis QB of the distal end side link hub 13 is inclined with respect to the central axis QA of the proximal end side link hub 12.

  The attitude of the distal-side link hub 13 with respect to the proximal-side link hub 12 is changed with the intersection O between the central axis QA of the proximal-side link hub 12 and the central axis QB of the distal-side link hub 13 as the center of rotation. Be seen. FIG. 4 shows a state where the central axis QA of the proximal end side link hub 12 and the central axis QB of the distal end side link hub 13 are on the same line, and FIG. 5 shows the central axis QA of the proximal end side link hub 12. Shows a state in which the central axis QB of the distal end side link hub 13 has a certain operating angle. Even if the posture changes, the distance L (FIG. 7) between the spherical link centers PA and PB on the proximal side and the distal side does not change.

  In the parallel link mechanism 9, when all of the following conditions 1 to 4 are satisfied, the center link member 17 and the end link members 15 and 16 on the base end side and the tip end side with respect to the plane of symmetry of the center link member 17 are If the angular positional relationship is made the same on the base end side and the tip end side, the link hub 12 on the base end side and the end link member 15 on the base end side, and the link hub 13 on the tip end side and the tip end side are considered due to geometrical symmetry. The side end link member 16 moves the same.

(Condition 1) The angle of the central axis O1 of the rotation pair of the proximal and distal end side link members 15 and 16 and the proximal and distal end side link members 15 and 16 of each link mechanism 14 and the proximal end side and The lengths from the spherical link centers PA and PB on the tip side are equal to each other.
(Condition 2) The center axes O1 of the rotational pairs of the link hubs 12 and 13 on the proximal and distal ends of the link mechanism 14 and the end link members 15 and 16 on the proximal and distal ends, and the proximal and distal ends. The center axes O2 of the rotational pairs of the side end link members 15 and 16 and the center link 7 intersect the proximal and distal spherical link centers PA and PB on the proximal and distal sides.
(Condition 3) The end portion link member 15 on the base end side and the end portion link member 16 on the tip end side have the same geometric shape.
(Condition 4) The center link member 17 also has the same shape on the base end side and the front end side.

  As shown in FIGS. 1 to 6B, the link hub 12 on the base end side is composed of the base member 6 and three rotary shaft connecting members 21 integrally provided with the base member 6. ing. The base member 6 has a circular through hole 6a (FIG. 6 (A)) in the center, and three rotary shaft connecting members 21 are arranged at equal intervals in the circumferential direction around the through hole 6a. .. The center of the through hole 6a is located on the link hub center axis QA on the base end side. A rotary shaft 22 having an axis intersecting the base end side link hub central axis QA is rotatably connected to each rotary shaft connecting member 21. One end of the proximal end side link member 15 is connected to the rotary shaft 22.

  As shown in FIG. 6 (B) in which one end link member 15 on the proximal end side and both end peripheral portions thereof are enlarged, the rotary shaft 22 has a large diameter portion 22a, a small diameter portion 22b, and a male screw portion 22c. The small diameter portion 22b is rotatably supported by the rotary shaft connecting member 21 through two bearings 23. The bearing 23 is a ball bearing such as a deep groove ball bearing or an angular ball bearing. These bearings 23 are installed in an inner diameter groove 24 provided in the rotary shaft connecting member 21 in a fitted state, and are fixed by a method such as press fitting, adhesion, or caulking. The same applies to the types and installation methods of bearings provided on other rotating pairs.

  The rotating shaft 22 is arranged concentrically with the output shaft 52a of the speed reduction mechanism 52, which will be described later, at the large diameter portion 22a. Details of the connection structure will be described later. Further, one end of the end link member 15 on the base end side is connected to the rotary shaft 22 so as to rotate integrally with the rotary shaft 22. A cutout portion 25 is formed at one end of the end link member 15 on the base end side, and both side portions of the cutout portion 25 constitute a pair of inner and outer rotary shaft support portions 26 and 27. Through holes 26a and 27a are formed in the pair of rotary shaft support portions 26 and 27, respectively. The rotary shaft connecting member 21 is arranged in the notch 25, and the small diameter portion 22b of the rotary shaft 22 is inserted through the through holes 26a and 27a and the inner ring of the bearing 23. The male screw portion 22c of the rotary shaft 22 projects more inward than the inner rotary shaft support portion 27.

  A spacer 28 is fitted around the large-diameter portion 22a of the rotary shaft 22, and the end link member 15 on the base end side and the output shaft 52a of the reduction mechanism 52 are fixed by a bolt 29 via the spacer 28. .. Further, a nut 30 is screwed onto the male screw portion 22c of the rotary shaft 22. Spacers 31 and 32 are interposed between the inner ring of the bearing 23 and the pair of rotary shaft support portions 26 and 27, and preload is applied to the bearing 23 when the nut 30 is screwed.

  A rotary shaft 35 rotatably connected to one end of the center link member 17 is connected to the other end of the base end side end link member 15. The rotating shaft 35 of the central link member 17 has a large diameter portion 35a, a small diameter portion 35b, and a male screw portion 35c, like the rotating shaft 22 of the link hub 12, and the small diameter portion 32b has two bearings 36 interposed therebetween. Is rotatably supported at one end of the center link member 17. A notch portion 37 is formed at the other end of the base end side end link member 15, and both side portions of the notch portion 37 constitute a pair of inner and outer rotating shaft support portions 38 and 39. Through holes 38a and 39a are formed in the rotary shaft support portions 38 and 39, respectively. The male screw portion 35c of the rotary shaft 35 projects more inward than the inner rotary shaft support portion 39.

  One end of the center link member 17 is arranged in the cutout portion 37, and the small diameter portion 35b of the rotary shaft 35 is inserted through the through holes 38a and 39a and the inner ring of the bearing 36. Further, a nut 40 is screwed onto the male screw portion 35c of the rotary shaft 35. Spacers 41 and 42 are interposed between the inner ring of the bearing 36 and the pair of rotary shaft support portions 38 and 39, and preload is applied to the bearing 36 when the nut 40 is screwed.

  As shown in FIGS. 1 to 5, the distal end side link hub 13 has a flat plate-shaped tip member 40 and three rotary shaft connecting members 41 provided on the bottom surface of the tip member 40 at equal intervals in the circumferential direction. It consists of and. The center of the circumference on which each rotary shaft connecting member 41 is arranged is located on the link hub central axis QB on the tip side. A rotary shaft 43 whose axis intersects the link hub central axis QB is rotatably connected to each rotary shaft connecting member 41. One end of the end link member 16 on the tip side is connected to the rotary shaft 43 of the link hub 13 on the tip side. A rotary shaft 45, which is rotatably connected to the other end of the central link member 17, is connected to the other end of the end link member 16 on the tip end side.

  The rotary shaft 43 of the distal end side link hub 13 and the rotary shaft 45 of the central link member 17 also have the same shape as the rotary shaft 35, and the rotary shaft connecting member 41 and the rotary shaft connecting member 41 via two bearings (not shown). The other ends of the central link members 17 are rotatably connected to each other.

  The attitude control actuator 10 of the link actuating device 7 is a rotary actuator including a speed reduction mechanism 52, and is installed on the upper surface of the base member 6 of the link hub 12 on the proximal end side so as to be coaxial with the rotary shaft 22. .. The attitude changing actuator 10 and the speed reduction mechanism 52 are integrally provided, and the speed reduction mechanism 52 is fixed to the base member 6 by a motor fixing member 53. In this embodiment, the posture changing actuator 10 is provided in all of the three sets of link mechanisms 14. However, if the attitude changing actuator 10 is provided in at least two of the three link mechanisms 14, the attitude of the distal end side link hub 13 with respect to the proximal end side link hub 12 can be determined.

  In FIG. 6 (B), the reduction mechanism 52 has a flange output and has a large-diameter output shaft 52a. The tip end surface of the output shaft 52a is a flat flange surface 54 orthogonal to the center line of the output shaft 52a. The output shaft 52a is connected to the rotary shaft support portion 26 of the end link member 15 on the base end side with a bolt 29 via the spacer 28. The large-diameter portion 22a of the rotary shaft 22 constitutes a rotating pair of the proximal end side link hub 12 and the proximal end-side end link member 15, and the large diameter portion 22a is the output shaft 52a of the reduction mechanism 52. It fits in the inner diameter groove 57 provided in the.

  As shown in FIGS. 1 and 2, the linear motion mechanism 8 is a moving body 8a that is installed on a bracket 61 fixed to the base 4 and that can move back and forth in the vertical direction, and a drive source that moves this moving body 8a. And a motor 8b. A work body installation member 62 is attached to the moving body 8 a, and the work body installation member 62 penetrates through the through hole 6 a of the base member 6 and extends above the base member 6. A work body fixing member 63 is provided on the upper end of the work body installing member 62, and the work body 3 is fixed to the work body fixing member 63. As a result, by driving the linear motion mechanism 8, the work body 3 moves in the vertical direction, that is, along the central axis QA of the link hub 12 on the base end side.

  The tip member 40 of the tip-side link hub 13 is provided with a rod-shaped workpiece fixing member 65 extending downward along the central axis QB of the tip-side link hub 13, and the lower end of the workpiece fixing member 65 is provided. The work piece 2 is held by the. The work piece 2 has a three-dimensional shape of, for example, a cylindrical body having a circular planar shape as shown in FIG. 8A or a rectangular parallelepiped shape having a rectangular planar shape as shown in FIG. 8B. The bottom surface 2a (FIGS. 1 and 2), which is the surface opposite to the work body 3, is fixed to the lower end of the work body fixing member 65.

  In FIG. 1 and FIG. 2, in the case of this embodiment, the working body 3 is a cutting machine for working by the working portion 3 a contacting the working body 2. The central axis of the working portion 3a coincides with the central axis QA of the base end side link hub 12. The working unit 3a is composed of, for example, a rotary tool such as an end mill shown in FIGS. 9A, 9B, 10A and 10B. The rotary tool (working part 3a) shown in FIGS. 9A and 9B has a spherical tip and is mainly used for cutting a curved surface. The rotary tool (working part 3a) of FIGS. 10A and 10B has a conical tip, and is used for chamfering the center, for example. The work body 3 may perform work without contacting the work body 2. The work performed by the work body 3 on the work body 2 includes application of liquid, painting, inspection, etc., in addition to cutting.

  The working device 1 using the parallel link mechanism 9 has a total of 3 degrees of freedom, including the parallel link mechanism 9 having two degrees of freedom and the linear motion mechanism 8 having one degree of freedom. Even with a structure having three degrees of freedom, the following conditions A and B are set so that the work body 3 can work on each surface of the work body 2 except the bottom surface 2a.

(Condition A) The internal space S1 of the parallel link mechanism 9 in which the portion of the work piece 2 to be operated by the work piece 3 is the space between the proximal end side link hub 12 and the distal end side link hub 13. Is located in. That is, the work body 3 performs work on the work body 2 in the internal space S1.
(Condition B) The distance T from the spherical link center of the link hub of the proximal end side link hub 12 and the distal end side link hub 13 on which the work piece 2 is provided to the bottom surface 2a of the work piece 2 Is more than 1/2 of the distance L between the spherical link centers PA and PB of the base end side link hub 12 and the tip end side link hub 13. In the case of this embodiment, since the work piece 2 is provided on the tip-side link hub 13, the distance T from the spherical link center PB of the tip-side link hub 13 to the bottom surface 2a of the work piece 2 is It is 1/2 or more of the distance L between the spherical link centers PA and PB.

The reason why the work body 3 can work on each surface of the work body 2 except for the bottom surface 2a will be described below even with the configuration having three degrees of freedom.
The distance x between the intersection O of the central axes QA and QB of the proximal and distal link hubs 12 and 13 and the spherical link centers PA and PB is x = L / (2cos (θ / 2)). .. The distance x increases as the bending angle θ increases. Therefore, when the distance T from the spherical link center PB of the distal end side link hub 13 provided with the work piece 2 to the bottom surface 2a of the work piece 2 is T ≦ L / 2, the bending angle θ becomes large. As a result, the position of the bottom surface 2a of the work piece 2 moves in a direction away from the central axis QB of the link hub 13 on the base end side. When the position of the bottom surface 2a of the work piece 2 is far away from the central axis QA, the work piece 2 having a three-dimensional shape such as a plurality of side surfaces of a cube or a rectangular parallelepiped, side surfaces of a cylindrical member, a spherical surface of a sphere, or the like. The work unit 3 cannot approach the side surface to the bottom position.

  On the other hand, if T> L / 2, even if the bending angle θ changes, there is always a posture that satisfies T> L / (2cos (θ / 2)). The work body 3 can also approach the side surface of the. Therefore, even with the configuration having three degrees of freedom, it is possible to perform work in a contact state or a non-contact state with respect to the side surface of the three-dimensionally shaped work body 2.

Regarding the relationship between the distance T and the distance L, more specifically,
T ≧ L / (2cos (θmax / 2)) ... Equation 1
It is good to make the relationship of. Note that θmax is the maximum bending angle, which is the bending angle θ when the parallel link mechanism 9 operates up to the maximum operable range.

  When the parallel link mechanism 9 operates up to the maximum operable range, the distance L becomes L / (2cos (θmax / 2)). If the distance T is set to L / (2cos (θmax / 2)) or more, the area where the central axis of the working portion 3a of the work body 3 intersects the side surface of the work piece 2 within the working range of the maximum bending angle θmax. Increase and work range is wide.

Further, in order to prevent the work body 2 and the work body 3 from interfering with the central link member 17, the dimensional relationship of each part may be determined as follows. That is, the maximum distance from the central axis QB of the distal end side link hub 13 provided with the work piece 2 to the outer peripheral surface of the work piece 2 is M, and is a circle connecting the central portions of the inner side surfaces of the respective center link members 17. If the radius of a certain inner surface orbital circle is R,
R ≧ T · sin (θmax / 2) + M ... Equation 2
So that the relationship is established. Here, the maximum distance M is a radius when the plane shape of the work piece 2 is circular as shown in FIG. 8A, and is a rectangle when the plane shape of the work piece 2 is rectangular as shown in FIG. 8B. In some cases, it is the distance from the center of the rectangle to the corner. The “inner side surface” of the central link member 17 is a surface that faces the midpoint of a straight line PA-PB that connects the spherical link centers on the proximal end side and the distal end side.

  By configuring each link mechanism 14 of the parallel link mechanism 9 in this way, it is possible to avoid the work body 2 and the work body 3 from interfering with the central link member 17. Thereby, the movable range of the parallel link mechanism 9 and the working range of the link actuator 7 can be widened.

A specific operation of the work apparatus 1 will be described with reference to FIG.
Steps (A) to (C) of FIG. 11 show a process of performing work on the tip surface 2 b of the work piece 2 by the work piece 3, and steps (D) and (E) are steps of the work piece 2. The process of working with the work body 3 on the left side surface 2c is shown. In the step (A) of FIG. 11, the central axis QA of the link hub 12 on the proximal end side and the central axis QB of the link hub 13 on the distal end side coincide with each other, and the working portion of the working body 3 is located at the central position of the distal end surface 2b. 3a is in contact.

  From this state, the posture changing actuator 10 (FIGS. 1 and 2) is driven to tilt the parallel link mechanism 9 to the left side of the drawing, and the linear motion mechanism 8 (FIGS. 1 and 2) is driven to drive the work unit 3 Move upwards. As a result, as in steps (B) and (C) of FIG. 11, the working portion 3a of the working body 3 moves from the central position to the left end while contacting the tip end surface 2b of the work piece 2, and the tip end surface is moved. Work on 2b. The posture changing actuator 10 and the linear motion mechanism 8 are controlled to operate in cooperation with each other.

  From the state of the step (C) of FIG. 11, similarly to the above, by tilting the parallel link mechanism 9 to the left side of the drawing and moving the work body 3 upward, the work portion 3a of the work body 3 causes the work body 3 to move. The left side face 2c is moved from the lower end to the upper end while contacting the left side face 2c, and the left side face 2c is worked (steps (D) and (E) in FIG. 11). By changing the inclination direction of the parallel link mechanism 9, the right side surface and the front and rear side surfaces of the work piece 2 can be similarly worked.

  As shown in step (E) of FIG. 11, when the parallel link mechanism 9 is tilted to the maximum bending angle θmax, the working portion 3a of the working body 3 comes into contact with the upper end of the side surface 2c of the working body 2. Then, the work can be performed on each surface of the work piece 2 except the bottom surface 2a. In this case, the working range is widened by making the relationship of the above expression 1 hold. Further, by satisfying the relationship of the expression 2, the movable range of the parallel link mechanism 9 and the working range of the link operating device 7 can be widened.

  In this way, the working device 1 using the parallel link mechanism 9 operates the link operating device 7 to change the posture of the work piece 2 installed on the link hub 13 on the distal end side, and at the same time, by the linear motion mechanism 8. By moving the work body 3 in the uniaxial direction, the work body 3 can perform contact work or non-contact work on each surface of the work body 2 excluding the bottom surface. Since the posture of the work piece 2 can be changed at high speed and with high precision by the link operating device 7, high speed and high precision work is possible.

  As in this embodiment, the central axis of the working portion 3a of the working body 3 is made to coincide with the central axis QA of the base end side link hub 12, and the working body 3 is moved by the linear motion mechanism 8 to the proximal end side link hub 12. When moved along the central axis QA, the relational expression for calculating the positions of the work body 3 and the work body 2 becomes relatively simple, and the posture control actuator 10 and the linear motion mechanism 8 can be easily controlled.

  For example, in operations such as liquid application, painting, and cutting, the work body 3 often has a larger bulk and mass than the work body 2. Since the work body 3 having a bulk and mass larger than that of the work body 2 is provided on the link hub 12 on the base end side, the load on the posture changing actuator 10 can be reduced. As a result, the working apparatus 1 is downsized and the cost is reduced.

  Further, the work body 3 works on the work body 2 in the internal space S1 of the parallel link mechanism 9. Therefore, as compared with the case where work is performed outside the internal space S1, the center of gravity of the work piece 2 provided on the distal end side link hub 13 is on the base end side and the front end side, which are the rotation centers of the parallel link mechanism 9. It is close to the intersection O of the central axes QA and QB of the link hubs 12 and 13. For this reason, the moment of inertia of the work piece 2 becomes small, and even when the work piece 2 having a large weight is provided on the distal end side link hub 13, high speed operation is possible. Further, it is possible to reduce the output, save energy, and make the posture changing actuator 10 compact.

  Hereinafter, different embodiments of the present invention will be described. In addition, in each of the following embodiments, members having the same configurations as those in the above-described embodiments are denoted by the same reference numerals, and description thereof will be omitted.

  The working apparatus 1 of the second embodiment shown in FIG. 12 employs a configuration using a ball screw mechanism as the linear motion mechanism 8. That is, the elevating table 72 is guided up and down by the plurality of shafts 70 extending downward from the base member 6 via the linear bush 71, and the work body installation member 62 is attached to the elevating table 72. The work body 3 is fixed to a work body fixing member 63 provided at the upper end of the work body setting member 62. A screw shaft 73 extends downward from the base member 6 in parallel with the shaft 70, and a nut 74 provided on the lifting table 72 is screwed onto the screw shaft 73. When the screw shaft 73 is rotated by the motor 75, the lift table 72 moves up and down, and the working body 3 moves along the central axis QA of the link hub 12 on the proximal end side. The linear motion mechanism 8 using this ball screw mechanism has a simpler structure and a lower height position of the base member 6 than the linear motion mechanism 8 of the first embodiment shown in FIGS. 1 and 2. There is an advantage that you can.

  In the working device 1 of the third embodiment shown in FIG. 13, the parallel link mechanism 9 is installed so that the link hub 13 on the tip side is on the lower side, and the linear motion mechanism 8 is arranged above the parallel link mechanism 9. is there. The work piece 2 is installed on the distal end side link hub 12, and the work piece 2 is moved by the linear motion mechanism 8 along the central axis QA of the base end side link hub 12. Although the linear motion mechanism 8 of FIG. 13 has a configuration using a ball screw mechanism, it may be the linear motion mechanism 8 used in the working apparatus 1 of the first embodiment of FIGS. 1 and 2.

  According to the third embodiment, the posture control actuator 10, the control device such as the linear motion mechanism 8 and the work body 3 are not arranged below the work body 2. As a result, it is possible to prevent chips and the like generated from the work piece 2 and grease, paint, etc. attached to the work piece 2 from adhering to and adversely affecting the control equipment and the work piece 3.

  The work device 1 of the fourth embodiment shown in FIG. 14 has the same arrangement of the parallel link mechanism 9 and the linear motion mechanism 8 as the work device 1 of the first embodiment shown in FIGS. Is installed on the distal end side link hub 12, and the work piece 3 is moved by the linear motion mechanism 8 along the central axis QA of the proximal end side link hub 12. That is, as compared with the working apparatus 1 of the first embodiment shown in FIGS. 1 and 2, the work piece 2 and the work piece 3 are arranged in reverse. In this case as well, by operating the link operating device 7 and the linear motion mechanism 8, the work body 3 can work on each surface of the work body 2 except the bottom surface 2a.

  In the working apparatus 1 according to the fifth embodiment shown in FIG. 15, the work piece 2 is provided on the distal end side link hub 13 and is installed on the pedestal 77 that serves as a fixed portion of the work piece 2, and the linear motion mechanism 8 operates the link. By moving the entire device 7, the work body 2 and the work body 3 are relatively moved in the uniaxial direction. Specifically, the work body installation member 62 is attached to the gantry 77, and the work body 3 is fixed to the work body fixing member 63 provided at the upper end of the work body installation member 62.

The linear motion mechanism 8 has a structure using a ball screw mechanism, and guides the base member 6 of the link hub 12 on the proximal end side so as to be able to move up and down through a plurality of shafts 70 extending upward from the base 4 via linear bushes 71. Has been done. A screw shaft 73 extends upward from a motor 75 installed on the base 4 in parallel with the shaft 70, and a nut 74 provided on the base member 6 is screwed onto the screw shaft 73. When the screw shaft 73 is rotated by the motor 75, the base member 6 moves up and down, and the working body 3 moves along the central axis QA of the link hub 12 on the base end side.
In this case as well, similarly to the above, by providing the work body 3 having a larger bulk and mass than the work body 2 on the link hub 12 on the proximal end side, the load of the posture changing actuator 10 can be reduced. As a result, the working apparatus 1 is downsized and the cost is reduced.

  Next, a rotation mechanism for rotating the work piece about an axis orthogonal to the central axis of the link hub of the proximal end side and the tip end side link hub on which the work piece is provided is provided. Another embodiment will be described. However, each of the following embodiments is an example in which the work body 3 is installed on the base end side link hub 12 and the work piece 2 is installed on the front end side link hub 13.

  The working apparatus 1 of the sixth embodiment shown in FIGS. 16 and 17 is provided with a rotating mechanism 90 for rotating the work piece 2 with respect to the working apparatus 1 having the three degrees of freedom shown in FIGS. The structure has four degrees of freedom. While the working apparatus 1 of the first embodiment shown in FIGS. 1 and 2 holds the work piece 2 at the lower end of the work piece fixing member 65 provided on the tip end member 40 of the link hub 13 on the tip end side. In the working device 1 of the sixth embodiment shown in FIGS. 16 and 17, the work piece 2 is installed on the distal end side link hub 13 as described below.

  That is, one end of the rotation mechanism fixing member 91 is fixed to the outer peripheral edge of the tip member 40 of the link hub 13 on the tip side. The rotating mechanism fixing member 91 extends toward the base end side link hub 12 in parallel with the central axis QB of the leading end side link hub 13, and the other end is located in the external space S2 of the parallel link mechanism 9. The external space S2 is a space outside the internal space S1. The rotation mechanism 90 is installed at the other end of the rotation mechanism fixing member 91. The rotating mechanism 90 is, for example, a motor.

  The output shaft 90a of the rotating mechanism 90 projects toward the internal space S1 along an axis 92 orthogonal to the central axis QB of the distal end side link hub 13, and the work to be extended coaxially with the output shaft 90a. The body fixing member 93 is fixed. The workpiece fixing member 93 has its tip inserted into the internal space S1 through between two adjacent sets of the link mechanisms 14 of the three or more sets of the link mechanisms 14. The work piece 2 is installed at the tip of the work piece fixing member 93. The work piece 2 is, for example, a cylindrical body whose central axis is the shaft 92. The work piece 2 may have another shape, such as a cube, a rectangular parallelepiped, or a sphere.

  In the sixth embodiment, the parallel link mechanism 9 has two degrees of freedom, the linear motion mechanism 8 has one degree of freedom, and the rotating mechanism has one degree of freedom of 90, which constitutes a total of four degrees of freedom. Despite having a four-degree-of-freedom structure, of course, as shown in FIG. 17, the end face of the work piece 2 is worked, and by rotating the work piece 2 around the shaft 92 by the rotating mechanism 90, Work can be performed on the entire peripheral surface of the work piece 2.

  Further, since the rotating mechanism 90 is arranged in the external space S2 of the parallel link mechanism 9 which has a sufficient space, it is possible to prevent each link mechanism 14 and the rotating mechanism 90 from interfering with each other, and to realize a wider operating range. .. Since the center of rotation of the work piece 2 by the rotating mechanism 90 coincides with the axis 92 orthogonal to the central axis QB of the link hub 13 on the tip side, the work position of the work piece 3 by the work piece 3 is calculated. The relational expression is relatively simple, and the posture control actuator 10 and the linear motion mechanism 8 can be easily controlled.

  The working apparatus 1 of the seventh embodiment shown in FIG. 18 is the working apparatus 1 of the second embodiment shown in FIG. 12 provided with a rotating mechanism 90 for rotating the work piece 2. The rotating mechanism 90 and the work piece 2 are installed on the distal end side link hub 13 as in the working apparatus 1 according to the sixth embodiment shown in FIGS. 16 and 17. As a result, the same action and effect as those of the working device 1 according to the sixth embodiment shown in FIGS. 16 and 17 can be obtained.

  The working apparatus 1 of the eighth embodiment shown in FIG. 19 is the working apparatus 1 of the third embodiment shown in FIG. 13 provided with a rotating mechanism 90 for rotating the work piece 2. The rotating mechanism 90 and the work piece 2 are installed on the distal end side link hub 13 as in the working apparatus 1 according to the sixth embodiment shown in FIGS. 16 and 17. As a result, the same action and effect as those of the working device 1 according to the sixth embodiment shown in FIGS. 16 and 17 can be obtained.

  In the working device 1 of the ninth embodiment shown in FIG. 20, the work body 3 is fixed in position and the entire link actuating device 7 is moved by the linear motion mechanism 8 similarly to the working device 1 of the fifth embodiment shown in FIG. The rotating mechanism 90 for rotating the work piece 2 is provided in the configuration described above. However, the configurations for moving the link operating device 7 are different from each other. The rotating mechanism 90 and the work piece 2 are installed on the distal end side link hub 13 as in the working apparatus 1 according to the sixth embodiment shown in FIGS. 16 and 17. As a result, the same action and effect as those of the working device 1 according to the sixth embodiment shown in FIGS. 16 and 17 can be obtained.

  A configuration for moving the link operating device 7 of the work device 1 according to the ninth embodiment shown in FIG. 20 will be described. A plurality of columns 5 are built on the base 4, and a horizontal frame 77 is supported by the plurality of columns 5. The work body installation member 62 is attached to the gantry 77, and the work body 3 is fixed to a work body fixing member 63 provided at the upper end of the work body installation member 62.

  The linear motion mechanism 8 is configured using a ball screw mechanism, and guides the base member 6 of the base end side link hub 12 so as to be able to ascend and descend via a linear bush 71 to a plurality of shafts 70 extending upward from the gantry 77. Has been done. A screw shaft 73 extends upward in parallel with the shaft 70 from a motor 75 installed on the bottom surface of the gantry 77, and a nut 74 provided on the base member 6 is screwed onto the screw shaft 73. When the screw shaft 73 is rotated by the motor 75, the base member 6 moves up and down, and the working body 3 moves along the central axis QA of the link hub 12 on the base end side.

  As described above, the preferred embodiments have been described with reference to the drawings, but a person skilled in the art will easily think of various changes and modifications within the obvious range by viewing the present specification. Therefore, such changes and modifications shall be construed as being within the scope of the present invention defined by the appended claims or equivalent thereto.

DESCRIPTION OF SYMBOLS 1 Working device 2 Workpiece 2a Bottom surface 3 Workpiece 3a Working part 8 Direct acting mechanism 9 Parallel link mechanism 10 Posture changing actuator 12 Base end side link hub 13 Tip side link hub 14 Link mechanism 15 Base end side end Part link member 16 End link member 17 on the front end side Central link member 90 Rotating mechanism 90a Output shaft 91 Rotating mechanism fixing member 92 Shaft 93 Workpiece fixing member O1 Central axis O2 of the rotating pair of the link hub and the end link member Center axes PA and PB of the rotational pairs of the partial link member and the center link member, center axes of spherical link QA and QB link hubs S1 inner space S2 outer space

Claims (7)

A work device for performing work in a contact state or a non-contact state with a work body with respect to a work body,
A parallel link mechanism that supports the work body or the work body so that the posture can be changed, an attitude control actuator that operates the parallel link mechanism, and the work body and the work body relative to each other in one axial direction. With a direct acting mechanism to move,
The parallel link mechanism connects the distal end side link hub to the proximal end side link hub via three or more sets of link mechanisms so that the posture can be changed, and each of the link mechanisms is connected to the proximal end side link hub. One end is rotatably connected to the link hub and the tip-side link hub, and the other is the end link member on the base end side and the tip end side. A center link member that is rotatably connected, and the link hub on the distal end side is provided with one of the work piece and the work piece whose posture is changed,
The attitude control actuator is provided in two or more sets of link mechanisms out of the three or more sets of link mechanisms so as to arbitrarily change the attitude of the distal end side link hub with respect to the proximal end side link hub. In the parallel link mechanism, the proximal end side link hub, the distal end side link hub, and the three or more sets of link mechanisms include a distal end side link hub with respect to the proximal end side link hub. A two-degree-of-freedom mechanism that can rotate around two orthogonal axes is configured,
The linear motion mechanism includes central axes of the rotating pairs of the proximal and distal end side link hubs and the proximal and distal end side link members, and the proximal and distal end side link members. And the point where the central axes of the rotational pairs of the central link member intersect with each other is referred to as the spherical link center of the base hub on the proximal side and the distal side, and the base passes through the spherical link centers on the proximal side and the distal side. When a straight line that intersects at right angles with the center axes of the rotation pairs of the end side and tip side link hubs and the base side and tip side end link members is referred to as the center axes of the base side and tip side link hubs, To relatively move the work piece and the work piece coaxially or in parallel with the central axis of the link hub on the base end side,
A portion of the work piece to be operated by the work body is located in an internal space between the base end side link hub and the tip end side link hub, and the base end side link hub and A bottom surface, which is a surface of the outer surface of the work piece opposite to the work piece from the spherical link center of the one of the link hubs on which the work piece is provided, of the distal end side link hubs. To the base end side link hub and the tip end side link hub is a working device using a parallel link mechanism that is ½ or more of the distance between the spherical link centers.   In the working device using the parallel link mechanism according to claim 1, the central axis of the link hub of the proximal end side link hub and the distal end side link hub on which the workpiece is provided is A working device using a parallel link mechanism that passes through at least a part of a work body, and has a central axis of the other link hub that matches a central axis of a working portion that is a portion of the working body that works on the work piece. The working device using the parallel link mechanism according to claim 1 or 2, wherein a link hub of the one of the base end side link hub and the tip end side link hub provided with the work piece is provided. The distance from the spherical link center to the bottom surface of the work piece is T, the distance between the spherical link center of the proximal end side link hub and the distal end side link hub is L, and the parallel link mechanism is When the maximum bending angle, which is the angle formed by the central axis of the proximal end side link hub and the central axis of the distal end side link hub in the state of operating up to the maximum operable range, is θmax,
T ≧ L / (2cos (θmax / 2))
A work device using a parallel link mechanism in which In the working device using the parallel link mechanism according to any one of claims 1 to 3, the work object of the base end side link hub and the tip end side link hub is provided. The maximum distance from the central axis of one of the link hubs to the outer peripheral surface of the work piece is M, the radius of the inner surface orbital circle that is the circle connecting the central portions of the inner surface of each central link member is R, and the tip end The distance from the spherical link center of the link hub to the bottom surface of the work piece is T, and the central axis of the proximal end side link hub and the tip end in a state in which the parallel link mechanism is operated to the maximum operable range. When the maximum bending angle, which is the angle formed by the center axis of the side link hub, is θmax,
R ≧ T ・ sin (θmax / 2) + M
A work device using a parallel link mechanism in which   The working device using the parallel link mechanism according to any one of claims 1 to 4, wherein the work piece is provided on the distal end side link hub, and the linear motion mechanism is provided on the proximal end side. A working device using a parallel link mechanism which is installed on a link hub and moves the working body by this linear motion mechanism.   In the working device using the parallel link mechanism according to claim 5, the parallel link mechanism is installed so that the link hub on the tip side faces downward, and the linear motion mechanism is arranged above the parallel link mechanism. A work device using a parallel link mechanism.   The working apparatus using the parallel link mechanism according to claim 1, wherein the work body is provided on the distal end side link hub, and the work body serves as a fixed portion. A working device using a parallel link mechanism, which is installed in a vehicle and is moved in the uniaxial direction relative to the work body by moving the entire parallel link mechanism by the linear motion mechanism.

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