JP2018194056A - Link operation device - Google Patents

Abstract

To provide a link operation device capable of performing high-speed, high-accuracy and wide-range operation, having a compact radial dimension, and having high degree of freedom for design on arrangement of an actuator for posture control.SOLUTION: A link operation device is configured such that a link hub on a tip side is connected to a link hub 2 on a base end side so as to be able to change a posture through three or more sets of link mechanisms. Each link mechanism 4 has end part link members 5, 6, and a central link member 7. In two or more link mechanisms, an actuator 50 for posture control is provided. The link hub 2 on the base end side has a base end member 10 supporting each link mechanism 4. With respect to the base end member 10, a revolute pair of central axes O1 of the link hub 2 on the base end side and the end part link member 5 on the base end side, and an output shaft 50a of the actuator 50 for posture control are arranged so as to be opposite to each other.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a link actuating device used for equipment requiring a wide operating range with high speed and high accuracy, such as medical equipment and industrial equipment.

  Patent Documents 1 and 2 propose parallel link mechanisms used for various working devices such as medical equipment and industrial equipment.

JP 2000-94245 A US Pat. No. 5,893,296

  The parallel link mechanism of Patent Document 1 is relatively simple in configuration, but since the operating angle of each link is small, if the operating range of the traveling plate is set large, the link length becomes long, so that the dimensions of the entire mechanism are reduced. There is a problem that the size of the device increases and the size of the device increases. There is also a problem that the rigidity of the whole mechanism is low and the weight of the tool mounted on the traveling plate, that is, the weight of the traveling plate is limited to a small weight.

  The parallel link mechanism of Patent Document 2 has a configuration in which the distal end side link hub is connected to the proximal end side link hub through three or more sets of four-bar linkages so that the posture can be changed. Although it is compact, it can operate in a wide range of operation with high speed and high accuracy.

  However, when the parallel link mechanism of Patent Document 2 is provided with a posture control motor, a speed reduction mechanism, and the like to form a link actuating device, the motor and the speed reduction mechanism are disposed outside the parallel link mechanism in the radial direction. There is a problem of becoming larger. There is also a problem that the operating range is limited due to interference between the speed reduction mechanism and the motor and the link mechanism.

  An object of the present invention is to provide a link actuating device that can operate in a wide operating range at high speed and with high accuracy, has a compact radial dimension, and has a high degree of freedom in design of an arrangement of an attitude control actuator. It is.

In the link actuating device according to the present invention, a distal end side link hub is connected to a proximal end side link hub through 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. The link hub and the distal end side link hub have one end rotatably connected to the proximal end side and the distal end side end link member, and both ends at the other end of the proximal end side and the distal end side end link member. A central link member rotatably connected to each other, and the two or more sets of the three or more sets of link mechanisms have a posture of the link hub on the distal end side with respect to the link hub on the proximal end side. An attitude control actuator that is arbitrarily changed is provided.
In this link actuating device, the base end side link hub has base end members that support the link mechanisms, and the base end side link hub and the base end side link hub are in relation to the base end member. The center axis of the rotational pair of the end link member and the output shaft of the attitude control actuator are arranged on opposite sides.

  According to this configuration, when each attitude control actuator is rotationally driven, the rotational power is transmitted to the end link member on the base end side. Thereby, the angle of the end link member on the base end side is changed, and the attitude of the link hub on the front end side with respect to the link hub on the base end side is changed. The parallel link mechanism is configured by connecting the link hub on the distal end side to the link hub on the base end side through three or more sets of four-link chains so that the posture can be changed. High accuracy and wide range of operation is possible.

  In this configuration, the center axis of the rotation pair of the base end side link hub and the base end side end link member and the output shaft of the attitude control actuator are arranged opposite to each other with respect to the base end member. Therefore, the attitude control actuator and the components associated with the attitude control actuator are not arranged around the rotation pair of the base end side link hub and the base end side end link member. For this reason, the attitude control actuator and the parallel link mechanism are unlikely to interfere with each other, and the parallel link mechanism can take a wide operating range while having a compact radial dimension. In addition, since the posture control actuator is arranged at the above position, there is no component of the parallel link mechanism on the surface of the base member opposite to the side where each link mechanism is located, and the posture control actuator is arranged. High design freedom.

In this invention, the base end side link hub has a plurality of rotation support members that protrude from the base end member toward the front end side and rotatably support the base end side end link members. The output shaft of the attitude control actuator may be parallel to an arrangement surface of the plurality of rotation support members in the base end member.
In this case, the output shaft of the attitude control actuator can be provided close to the base end member as a whole. Thereby, the dimension of the direction along the central axis of the link hub of the base end side of the whole link actuator can be made compact.
The central axis of the link hub on the base end side is the central axis of each rotation pair of the link hub on the base end side and the end link member on the base end side, and the end link member on the base end side and the When the central axis of each rotation pair of the central link member intersects with the spherical link center on the base end side, the base link side hub and the base end pass through this spherical link center on the base end side. It refers to a straight line that intersects the central axis of each rotation pair of the side end link member at a right angle.

In this invention, the base end side link hub has a plurality of rotation support members that protrude from the base end member toward the front end side and rotatably support the base end side end link members. The central axis of the rotation pair of the base end side link hub and the base end side end link member may be parallel to the arrangement surface of the plurality of rotation support members in the base end member.
In this case, the central axis of the rotation pair of the base end side link hub and the base end side end link member can be provided close to the base end member as a whole. Thereby, the dimension of the direction along the central axis of the link hub of the base end side of the whole link actuator can be made compact.

In this invention, the base end member may have a through hole in a central portion of the row of the plurality of rotation support members.
When the through-hole is provided, the through-hole can be provided through the wiring or the like, and the wiring or the like can be easily handled.

In the present invention, the attitude control actuator may be disposed inward with reference to the output shaft.
With this configuration, the radial dimension of the portion where the attitude control actuator is disposed is reduced, and a compact configuration can be realized. In addition, the size in the direction along the central axis of the link hub on the base end side is compact as compared with the configuration in which the attitude control actuator is arranged in the direction along the central axis of the link hub on the base end side.

When the posture control actuator is disposed inward with respect to the output shaft, the output shaft of the posture control actuator is connected to the proximal end side link hub and the proximal end side link. You may arrange | position offset in parallel with respect to the plane which the center axis | shaft of each rotation pair of a member and the center axis | shaft of the said link end side link hub comprise.
By arranging the posture control actuators offset, it is possible to avoid the posture control actuators from interfering with each other. In addition, a space for wiring and the like can be widened in the central portion in the radial direction of the portion where the attitude control actuator is disposed.

In the present invention, the proximal-side end link member includes a curved portion that is curved at an arbitrary angle, and a rotational coupling portion that is provided at one end of the curved portion and includes a pair of rotationally coupled bodies arranged at intervals. A reduction mechanism that decelerates the rotational power of the attitude control actuator and transmits it to the base end side end link member may be disposed between the pair of rotary coupling bodies.
In this case, since the end link member on the base end side is curved at the bending portion, the radial dimension of the entire link operating device can be reduced, and a compact configuration can be realized. Further, by disposing the speed reduction mechanism between the pair of rotating coupling bodies, the speed reduction mechanism can be installed without projecting radially outward, and a more compact configuration can be realized. In addition, when the speed reduction mechanism is disposed between the pair of rotation coupling bodies, the speed reduction mechanism is connected to the pair of rotation coupling bodies, which is advantageous in improving the rigidity.

  In the link actuating device according to the present invention, a distal end side link hub is connected to a proximal end side link hub through 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. The link hub and the distal end side link hub have one end rotatably connected to the proximal end side and the distal end side end link member, and both ends at the other end of the proximal end side and the distal end side end link member. A central link member rotatably connected to each other, and the two or more sets of the three or more sets of link mechanisms have a posture of the link hub on the distal end side with respect to the link hub on the proximal end side. In the link actuating device provided with the posture control actuator to be arbitrarily changed, the link hub on the base end side includes base end members that support the link mechanisms, and the base end member is connected to the base end member. end Because the central axis of the rotational pair of the link hub and the end link member on the base end side and the output shaft of the attitude control actuator are arranged on opposite sides, high speed, high accuracy and wide range of operation A range of operations can be performed, the radial dimension is compact, and the degree of freedom in design of the position control actuator arrangement is high.

It is the front view which omitted a part of link operating device concerning a 1st embodiment of this invention. It is a figure which shows one state of the parallel link mechanism of the link actuating device. It is a figure which shows the different state of the parallel link mechanism. It is IV-IV sectional drawing of FIG. It is VV sectional drawing of FIG. It is VI-VI sectional drawing of FIG. It is VII-VII sectional drawing of FIG. It is VIII-VIII sectional drawing of FIG. It is the figure which expressed one link mechanism of the parallel link mechanism with a straight line. It is the front view which abbreviate | omitted some link actuating devices concerning 2nd Embodiment of this invention. It is XI-XI sectional drawing of FIG. It is the front view which abbreviate | omitted some link actuating devices concerning 3rd Embodiment of this invention. It is XIII-XIII sectional drawing of FIG. It is XIV-XIV sectional drawing of FIG. It is XV-XV sectional drawing of FIG. It is the front view which abbreviate | omitted some link actuating devices concerning 4th Embodiment of this invention. It is XVII-XVII sectional drawing of FIG. It is XVIII-XVIII sectional drawing of FIG. It is the front view which abbreviate | omitted some link actuating devices concerning 5th Embodiment of this invention. It is XX-XX sectional drawing of FIG. FIG. 21 is a partial cross-sectional view of FIG. 20. It is XXII-XXII sectional drawing of FIG.

An embodiment of the present invention will be described with reference to the drawings.
[First Embodiment]
1 to 9 show a first embodiment. FIG. 1 is a front view in which a part of the link operating device is omitted. The link actuating device includes a parallel link mechanism 1 and a plurality of attitude control actuators 50 that actuate the parallel link mechanism 1. In the link actuating device shown in FIG. 1, the parallel link mechanism 1 is supported vertically on the upper ends of a plurality of columns 101 installed on a base plate 100.

FIG. 2 is a diagram showing one state of the parallel link mechanism 1, and FIG. 3 is a diagram showing different states of the parallel link mechanism 1. 2 and 3 show a state seen from the opposite direction to FIG. The parallel link mechanism 1 is configured such that a distal end side link hub 3 is connected to a proximal end side link hub 2 via three sets of link mechanisms 4 so that the posture can be changed. In FIG. 1, only one set of link mechanisms 4 is shown. The number of link mechanisms 4 may be four or more.
2 and 3 show the basic configuration of the parallel link mechanism 1. When the attitude control actuator 50 or the like is attached to form a link operating device, a part of the parallel link mechanism 1 is different from the drawing. It becomes.

  1 to 3, each link mechanism 4 is composed of a base end side end link member 5, a front end side end link member 6, and a central link member 7, and is a four-bar chain consisting of four rotating pairs. The link mechanism is made. The end link members 5 and 6 on the proximal end side and the distal end side are L-shaped, and one ends thereof are rotatably connected to the link hub 2 on the proximal end side and the link hub 3 on the distal end side, respectively. The center link member 7 is rotatably connected to both ends of the end link members 5 and 6 on the proximal end side and the distal end side, respectively.

  The parallel link mechanism 1 has a structure in which two spherical link mechanisms are combined, and each rotation pair of the link hubs 2 and 3 and the end link members 5 and 6, and the end link members 5 and 6 and the central link member 7. The center axis of each rotation pair of the two crosses at the spherical link centers PA and PB (FIG. 1) on the proximal end side and the distal end side. In addition, on the proximal end side and the distal end side, the distances from the rotary pairs of the link hubs 2 and 3 and the end link members 5 and 6 and the respective spherical link centers PA and PB are the same. The distances from the rotary pairs of 6 and the central link member 7 and the spherical link centers PA and PB are also the same. The central axis of each rotational pair of the end link members 5 and 6 and the central link member 7 may have a certain crossing angle γ (FIG. 1) or may be parallel.

4, which is a cross-sectional view taken along the line IV-IV in FIG. 1, shows a central axis O1 of each rotation pair of the link hub 2 on the base end side and the end link member 5 on the base end side, the center link member 7 and the base end side The relationship between the center axis O2 of each rotation pair of the end link member 5 and the spherical link center PA on the base end side is shown. That is, the point where the central axis O1 and the central axis O2 intersect is the spherical link center PA on the base end side.
FIG. 7, which is a cross-sectional view taken along the line VII-VII in FIG. The relationship between the center axis O2 of each rotation pair of the partial link member 6 and the spherical link center PB on the tip side is shown. That is, the point where the central axis O1 and the central axis O2 intersect is the spherical link center PB on the tip side.
In the example of FIGS. 4 and 7, the central axis O1 of each rotation pair of the link hubs 2 and 3 and the end link members 5 and 6, and each rotation pair of the end link members 5 and 6 and the center link member 7. Although the angle α formed by the central axis O2 of the angle α is 90 °, the angle α may be other than 90 °.

  The three sets of link mechanisms 4 have the same geometric shape. As shown in FIG. 9, the geometrically identical shape is a geometric model in which the link members 5, 6, and 7 are expressed by straight lines, that is, a model that is expressed by each rotation pair and a straight line connecting these rotation pairs. However, it says that the base end side part with respect to the center part of the center link member 7 and a front end side part are the shapes which make symmetry. FIG. 9 is a diagram in which a set of link mechanisms 4 is expressed by a straight line. The parallel link mechanism 1 of this embodiment is a rotationally symmetric type, and includes a base end side link hub 2 and a base end side end link member 5, a front end side link hub 3 and a front end side end link member 6. The positional relationship is such that it is rotationally symmetric with respect to the center line C of the central link member 7. The center part of each center link member 7 is located on a common track circle.

  With the link hub 2 on the proximal end side, the link hub 3 on the distal end side, and the three sets of link mechanisms 4, the link hub 3 on the distal end side is rotatable about two orthogonal axes with respect to the link hub 2 on the proximal end side. A degree mechanism is configured. In other words, it is a mechanism that can freely change the posture of the link hub 3 on the distal end side with respect to the link hub 2 on the proximal end side with two degrees of freedom of rotation. Although this two-degree-of-freedom mechanism is compact, the movable range of the link hub 3 on the distal end side with respect to the link hub 2 on the proximal end side can be widened.

  For example, a straight line that passes through the spherical link centers PA and PB and intersects the link hubs 2 and 3 and the central axis O1 (FIGS. 4 and 7) of the rotation pairs of the end link members 5 and 6 at right angles is linked hubs 2 and 3. Center axes QA and QB, the maximum value of the bending angle θ (FIG. 9) between the center axis QA of the link hub 2 on the proximal end side and the center axis QB of the link hub 3 on the distal end side is about ± 90 °. be able to. Further, the turning angle φ (FIG. 9) of the distal end side link hub 3 with respect to the proximal end side link hub 2 can be set in a range of 0 ° to 360 °. The bending angle θ is a vertical angle in which the central axis QB of the distal end side link hub 3 is inclined with respect to the central axis QA of the proximal end side link hub 2, and the turning angle φ is the proximal end side link hub. This is a horizontal angle at which the central axis QB of the link hub 3 on the distal end side is inclined with respect to the central axis QA of the second axis.

  The posture change of the link hub 3 on the distal end side with respect to the link hub 2 on the proximal end side is performed with the intersection O between the center axis QA of the link hub 2 on the proximal end side and the center axis QB of the link hub 3 on the distal end side as a rotation center. . 2 shows a state in which the central axis QA of the link hub 2 on the proximal end side and the central axis QB of the link hub 3 on the distal end side are on the same line, and FIG. 3 shows the central axis QA of the link hub 2 on the proximal end side. In contrast, a state in which the central axis QB of the link hub 3 on the distal end side takes a certain operating angle is shown. Even if the posture changes, the distance L (FIG. 9) between the spherical link centers PA and PB on the proximal end side and the distal end side does not change.

When each link mechanism 4 satisfies the following conditions, the link hub 2 on the proximal end side and the end link member 5 on the proximal end side, the link hub 3 on the distal end side, and the end portion on the distal end side due to geometric symmetry It moves in the same way as the link member 6. Therefore, the parallel link mechanism 1 functions as a constant velocity universal joint that rotates at a constant speed with the same rotation angle on the proximal end side and the distal end side when transmitting rotation from the proximal end side to the distal end side.
Condition 1: The angle and length of the central axis O1 of the rotational pair of the link hubs 2 and 3 and the end link members 5 and 6 in each link mechanism 4 are equal to each other.
Condition 2: The central axis O1 of the rotational pair of the link hubs 2 and 3 and the end link members 5 and 6 and the central axis O2 of the rotational pair of the end link members 5 and 6 and the central link member 7 are on the proximal side. And at the front end side, they intersect at spherical link centers PA and PB.
Condition 3: The geometric shapes of the proximal end side end link member 5 and the distal end side end link member 6 are equal.
Condition 4: The geometric shapes of the proximal end portion and the distal end portion of the central link member 7 are equal.
Condition 5: With respect to the symmetry plane of the central link member 7, the angular positional relationship between the central link member 7 and the end link members 5 and 6 is the same on the proximal end side and the distal end side.

  As shown in FIGS. 1 to 4, the link hub 2 on the base end side is provided with a flat plate-like base end member 10 that supports each link mechanism 4, and is equally distributed on the circumference of the base end member 10. And three rotation support members 11. In the example of the figure, a flat base end member 10 is provided such that the upper and lower surfaces are horizontal, and each rotation support member 11 protrudes upward from the upper surface of the base end member 10. As shown in FIG. 1, the parallel link mechanism 1 is supported by the base member 100 by connecting the upper end of the support column 101 to the bottom surface of the base end member 10. In addition, the base end member 10 does not need to be flat.

  As shown in FIG. 4, the center of the circumference where the three rotation support members 11 are arranged is located on the central axis QA of the link hub 2 on the proximal end side. In the base end member 10, a through hole 10 a is formed at the center of the rotation support members 11. The center of the through hole 10a is also located on the central axis QA of the link hub 2 on the proximal end side.

  As shown in FIG. 5 which is a VV sectional view of FIG. 1, one end of an end link member 5 on the base end side is rotatably connected to each rotation support member 11. Specifically, the rotation shaft 12 is rotatably supported by the rotation support member 11 via the two bearings 13, and one end of the end link member 5 on the proximal end side is connected to the rotation shaft 12.

  Further, the other end of the end link member 5 on the base end side is connected to one end of the central link member 7. Specifically, the rotation shaft 15 is rotatably supported by the central link member 7 via two bearings 16, and the other end of the end link member 5 on the proximal end side is connected to the rotation shaft 15. .

  The bearings 13 and 16 are ball bearings such as a deep groove ball bearing and an angular ball bearing. These bearings 13 and 16 are fixed to the rotation support member 11 or the central link member 7 by a method such as press fitting, adhesion, or caulking. Instead of using the bearings 13 and 16 as in this example, the rotary shafts 12 and 15 are rotatably contacted with the rotary support member 11 or the central link member 7 so that the rotary shafts 12 and 15 are rotatably supported. Also good. The same applies to the types and installation methods of the bearings provided in other rotating pairs.

  As shown in FIG. 1 to FIG. 3 and FIG. 7, the link hub 3 on the distal end side is composed of a flat-shaped distal end member 20 and three rotational supports provided equally on the circumference of the distal end member 20. It is comprised with the member 21. FIG. The center of the circumference where the three rotation support members 21 are arranged is located on the central axis QB of the link hub 3 on the distal end side. The tip member 20 may not be flat.

  As shown in FIG. 8 which is a VIII-VIII sectional view of FIG. 1, one end of an end link member 6 on the distal end side is rotatably connected to each rotation support member 21. Specifically, the rotation shaft 22 is rotatably supported by the rotation support member 21 via two bearings 23, and one end of the end link member 6 on the distal end side is connected to the rotation shaft 22.

  Further, the other end of the end-side end link member 6 is connected to the other end of the central link member 7. Specifically, the rotary shaft 25 is rotatably supported by the central link member 7 via two bearings 26, and the other end of the end link member 6 on the distal end side of the rotary shaft 25 is connected.

  Next, the configuration of the end link members 5 and 6 will be described with reference to FIGS. Since the end link members 5 and 6 on the proximal end side and the distal end side have the same configuration except for a part, the end link member 5 on the proximal end side will be described as a representative here, and the end link on the distal end side will be described. For 6, the code of the corresponding location is shown in parentheses. The parts having different configurations of the end link members 5 and 6 on the proximal end side and the distal end side will be described as needed.

  As shown in FIG. 5 (FIG. 8), the end link member 5 (6) is composed of one bending portion 30 and each rotation connecting portion on the link hub side and the central link side located at both ends of the bending portion 30. 31A and 31B. In this embodiment, each rotation connection part 31A, 31B consists of a pair of rotation connection body 31a, 31b each fixed to the outer surface and inner surface of the edge part of the bending part 30. As shown in FIG.

  The curved portion 30 is, for example, a cast product of a metal material, and has a shape curved at a predetermined angle α (see FIGS. 4 and 7; in this example, 90 °). The bending angle α can be arbitrarily determined. At both ends of the curved portion 30, one bolt screw hole 32 penetrating between the outer surface and the inner surface and two positioning holes 33 positioned on both sides of the bolt screw hole 32 are provided.

The rotary coupling bodies 31a and 31b of the rotary coupling portions 31A and 31B are made into a predetermined shape by processing a plate-like member having a constant thickness such as a metal plate. The shape of the rotary coupling bodies 31a and 31b is, for example, an elongated straight line, and one bolt insertion hole 34 corresponding to the bolt screw hole 32 of the bending portion 30 and two positioning positions corresponding to the positioning hole 33 of the bending portion 30. A hole 35 and a through hole 36 through which any one of the rotary shafts 12, 15, 22, and 25 is inserted are provided.
If a plate-like member having a simple shape and a constant thickness is used as the material of the rotary coupling bodies 31a and 31b, it can be manufactured at low cost and is excellent in mass productivity. In particular, when the material is a metal plate, the contour shape and the processing of the holes 34, 35, and 36 are easy.

When fixing the bending portion 30 and the rotary connecting bodies 31a and 31b, the positioning pins 37 are inserted into the positioning holes 33 of the bending portion 30 and the positioning holes 35 of the outer and inner rotary connecting bodies 31a and 31b. To do. In this state, the bolts 38 are inserted into the bolt insertion holes 34 of the rotary coupling bodies 31 a and 31 b from the outside and the inside, respectively, and the screw portions of the bolts 38 are screwed into the bolt screw holes 32 of the bending portion 30. That is, the outer and inner rotary coupling bodies 31 a and 31 b are individually fixed to the bending portion 30 by different bolts 38 while being positioned by the common positioning pin 37.
By using the positioning pin 37 in this way, the assembly becomes easy and the variation in the assembly accuracy by the operator is reduced. In addition, since the accuracy of the positional relationship between the bending portion 30 and the rotary coupling bodies 31a and 31b is improved, a smooth operation of the parallel link mechanism 1 can be realized.

  As shown in FIG. 5, the rotation support member 11 is disposed between the outer and inner rotation coupling bodies 31a and 31b in the link hub side rotation coupling portion 31A of the proximal end side end link member 5. The The end link member 5 and the rotation support member 11 are connected to each other via the rotation shaft 12 so as to be rotatable. Specifically, they are connected as follows.

  The rotary shaft 12 has a pulley attachment portion 12a for attaching a timing pulley 55 described later to the outer diameter end, and has a male screw portion 12b at the inner diameter end. The rotary shaft 12 is inserted from the male screw portion 12b side into the outer rotary coupling body 31a, the spacer 45, the inner ring of the two bearings 13, the spacer 46, and the through holes of the inner rotary coupling body 31b in order. A nut 47 is screwed to 12b. As a result, the timing pulley 55 and the nut 47 sandwich the pair of rotary coupling bodies 31a and 31b, the inner ring of the two bearings 13, and the two spacers 45 and 46 so that a preload is applied to the bearing 13. The end link member 6 and the rotation support member 21 are rotatably connected to each other. However, the timing pulley 55 is rotatable with respect to the outer rotary coupling body 31a.

  As shown in FIG. 8, the rotation support member 21 is disposed between a pair of outer and inner rotation coupling bodies 31a and 31b in the rotation coupling section 31A on the link hub side of the end link member 6 on the distal end side. . Then, the end link member 6 and the rotation support member 21 are rotatably connected to each other via the rotation shaft 22. Specifically, they are connected as follows.

  The rotating shaft 22 has a head portion 22a having a larger diameter than other portions at the outer diameter end, and has a male screw portion 22b at the inner diameter end. The rotary shaft 22 is inserted from the male screw portion 22b side into the outer rotary coupling body 31a, the spacer 45, the inner ring of the two bearings 23, the spacer 46, and the through holes of the inner rotary coupling body 31b in order. A nut 47 is screwed onto 22b. As a result, the head 22a of the rotating shaft 22 and the nut 47 sandwich the pair of rotary coupling bodies 31a and 31b, the inner ring of the two bearings 23, and the two spacers 45 and 46, thereby preloading the bearing 23. In the applied state, the end link member 6 and the rotation support member 21 are rotatably connected to each other.

  As shown in FIG. 5 (FIG. 8), the rotation link 31B on the center link side of the end link member 5 (6) is between the pair of rotation links 31a and 31b on the outside and inside. One end (the other end) is arranged. Then, the end link member 5 (6) and the central link member 7 are rotatably connected to each other via the rotary shaft 15 (25). Specifically, the connections are made as follows.

  The rotating shaft 15 (25) has a head portion 15a (25a) having a larger diameter than other portions at the outer diameter end, and has a male screw portion 15b (25b) at the inner diameter end. From the male screw portion 15b (25b) side, the rotary shaft 15 (25) is connected to the outer rotary coupling body 31a, the spacer 45, the inner ring of the two bearings 16 (26), the spacer 46, and the inner rotary coupling body 31b. The nuts 47 are inserted through the through holes in order, and the nuts 47 are screwed into the male screw portions 15b (25b). Thus, the head 15a (25a) of the rotary shaft 15 (25) and the nut 47 sandwich the pair of rotary coupling bodies 31a and 31b, the inner ring of the two bearings 16 (26), and the two spacers 45 and 46. By attaching, the end link member 5 (6) and the central link member 7 are rotatably connected to each other in a state where a preload is applied to the bearing 16 (26).

  6 is a cross-sectional view taken along the line VI-VI in FIG. An actuator support member 52 is provided projecting downward from the outer peripheral edge of the bottom surface of the base end member 10, and the posture control actuator 50 and the accompanying speed reduction mechanism 51 are attached to the outer surface of the actuator support member 52. Yes. Specifically, the attitude control actuator 50 and the attached speed reduction mechanism 51 are attached to the actuator support member 52 at the speed reduction mechanism 51.

  The attitude control actuator 50 is a rotary motor, and its output shaft 50 a extends horizontally through the actuator support member 52 to the inside of the actuator support member 52. Then, rotation is transmitted from the output shaft 50 a of the attitude control actuator 50 to the rotating shaft 12 by the belt-type power transmission mechanism 53. The belt-type power transmission mechanism 53 includes a driving side timing pulley 54 attached to the output shaft 50a, a driven side timing pulley 55 attached to the pulley attaching portion 12a of the rotating shaft 12, and both timing pulleys 54, 55. And a timing belt 56 hung on the belt. The timing belt 56 is passed through an opening 10 b opened in the base end member 10.

  This link actuating device operates the parallel link mechanism 1 by rotationally driving each attitude control actuator 50. Specifically, when the attitude control actuator 50 is rotationally driven, the rotational power is reduced by the speed reduction mechanism 51, and the reduced rotational power is transmitted to the rotary shaft 12 through the power transmission mechanism 53. Thereby, the angle of the end link member 5 on the base end side is changed, and the attitude of the link hub 3 on the distal end side with respect to the link hub 2 on the base end side is changed. The parallel link mechanism 1 has a compact structure because the distal end side link hub 3 is connected to the proximal end side link hub 2 via three sets of four-link chains 3 so that the posture can be changed. Nevertheless, it can operate in a wide range of operation with high speed and high accuracy.

  Since the end link members 5 and 6 are bent by the bending portion 30, the radial dimension of the entire link operating device can be reduced, and a compact configuration can be realized. Each of the rotation coupling portions 31A and 31B of the end link members 5 and 6 includes a pair of rotation coupling bodies 31a and 31b. Since the rotation coupling bodies 31a and 31b are made of a metal plate that is detachably attached to the bending portion 30, the rotation coupling bodies 31a and 31b can be manufactured at low cost and with high productivity by sheet metal processing. The rotary coupling bodies 31a and 31b can be made to correspond to the difference in the size of the link actuator only by changing the size of the metal plate as the material. For this reason, it is possible to easily change the size of the link operating device.

  Further, when the end link members 5 and 6 are divided into two types of parts, that is, the curved part 30 and the rotary connecting parts 31A and 31B, each part can be made into a simple shape, the processing cost can be suppressed, and the mass productivity can be suppressed. Will improve. If the rotary coupling bodies 31a and 31b of the rotary coupling portions 31A and 31B have the same shape, the parts can be shared, and the cost is low and the mass productivity is good. However, the thickness and shape of the rotary coupling bodies 31a and 31b may be varied depending on the location where the rotary coupling bodies 31a and 31b are used and the required strength.

  This link actuating device is configured such that the proximal end side link hub 2 and the proximal end side end link member 5 have a rotational axis of the central axis O1 and the attitude control actuator 50 output shaft 50a. Are disposed on opposite sides of each other. As a result, the posture control actuator 50 and the components associated with the posture control actuator 50 are not arranged around the rotation pair of the base end side link hub 2 and the base end side end link member 5. The For this reason, the attitude control actuator 50 and the parallel link mechanism 1 are unlikely to interfere with each other, and the parallel link mechanism 1 can take a wide operating range while having a compact radial dimension. Further, since the posture control actuator 50 is arranged at the above position, there is no component of the parallel link mechanism 1 on the surface of the base member 10 opposite to the side where each link mechanism 4 is located. The degree of freedom in designing the arrangement of the actuator 50 is high.

  Since the base end member 10 has a flat plate shape, the base end member 10 is provided with a plurality of rotation support members 11 without increasing the dimension in the direction along the central axis QA of the base end side link hub 2. Can be provided. In addition, since the output shaft 50 a of the attitude control actuator 50 is parallel to the base end member 10, the output shaft 50 a of the attitude control actuator 50 can be provided close to the base end member 10 as a whole. Further, since the central axis O1 of the rotating pair of the base end side link hub 2 and the base end side end link member 5 is parallel to the base end member 10, the central axis O1 is entirely connected to the base end member. 10 can be provided. From these things, the dimension of the direction in alignment with the central axis QA of the link hub 2 of the base end side of the whole link actuator can be made compact.

  Since the through-hole 10a is provided in the center part of the arrangement of the plurality of rotation support members 11 in the base end member 10, the through-hole 10a can be provided through the wiring and the like, and the wiring and the like can be easily routed.

[Second Embodiment]
10 and 11 show a second embodiment of the present invention. In this link actuating device, a power transmission mechanism 61 that transmits rotation from the output shaft 50a of the attitude control actuator 50 to the rotary shaft 12 is constituted by a gear train. That is, the power transmission mechanism 61 includes a drive gear 62 attached to the output shaft 50a, a counter gear 63 rotatably supported on the actuator support member 52, and a driven gear 64 attached to the rotary shaft 12. The A part of the counter gear 63 and the driven gear 64 is disposed in the opening 10 b opened in the base end member 10. In the example shown in the figure, each of the gears 62, 63, and 64 is a spur gear, but a gear train may be constituted by a gear other than the spur gear. Others are the same as the first embodiment.

  Thus, even when the power transmission mechanism 61 is a gear type, the same operation and effect as in the belt type can be obtained. The power transmission mechanism 61 in the figure has three gears, but it may be other than three. In the power transmission mechanism 61 shown in the figure, the rotation is transmitted in the same direction from the output shaft 50a of the attitude control actuator 50 to the rotating shaft 12, but it may be transmitted in the opposite direction.

[Third Embodiment]
12 to 15 show a third embodiment of the present invention. This link actuating device differs from the first embodiment in the arrangement of each attitude control actuator 50. In other words, in the first embodiment, each attitude control actuator 50 is arranged outward with respect to the output shaft 50a, whereas in the third embodiment, each attitude control actuator 50 has an output shaft. It is arranged inward with respect to 50a.

Specifically, an actuator support member 52 is provided at a position slightly inside the outer peripheral edge of the bottom surface of the base end member 10, and the attitude control actuator 50 and the speed reduction mechanism 51 are attached to the inner side surface of the actuator support member 52. ing. The output shaft 50a of the attitude control actuator 50 extends to the outer diameter side. An actuator rotation support member 66 is provided on the outer peripheral edge of the bottom surface of the base end member 10, and the output shaft 50 a is rotatably supported by the actuator rotation support member 66 via a bearing 67.
Others are the same as the first embodiment.

  If each attitude control actuator 50 is arranged inward in this manner, the radial dimension of the portion where the attitude control actuator 50 is arranged becomes small, and a compact configuration can be realized. Specifically, each posture control actuator 50 can be accommodated within a range below the base end member 10 so that it does not protrude outward from the base end member 10.

  Even if the attitude control actuator 50 is arranged vertically along the central axis QA of the link hub 2 on the base end side, the radial dimension can be made compact. The vertical dimension along the central axis QA of the link hub 2 on the side increases. On the other hand, the arrangement of the third embodiment can make both the radial dimension and the longitudinal dimension compact.

[Fourth Embodiment]
16 to 18 show a fourth embodiment of the present invention. In this link actuating device, the output shaft 50a of the attitude control actuator 50 is different from the third embodiment in that the center axis O1 of the rotational pair of the base end side link hub 2 and the base end side end link member 5 is O1. And the plane formed by the central axis QA of the link hub 2 on the base end side is offset in parallel.
Others are the same as the third embodiment.

  By arranging the posture control actuators 50 so as to be offset in this way, even if the posture control actuators 50 are long in the axial direction of the output shaft 50a, the posture control actuators 50 can be prevented from interfering with each other. it can. In addition, a space 68 for passing wiring or the like can be widened in the central portion in the radial direction of the portion where the attitude control actuator 50 is disposed. Accordingly, the through hole 10a of the base end member 10 is also enlarged.

[Fifth Embodiment]
19 to 22 show a fifth embodiment of the present invention. In this link operating device, the position of the speed reduction mechanism 51 is different from that in the fourth embodiment. That is, in the fourth embodiment, an attitude control actuator with a speed reducer in which the attitude control actuator 50 and the speed reduction mechanism 51 are combined together is used, but the link actuator of the fifth embodiment is As shown in FIG. 21, the speed reduction mechanism 51 is disposed between the pair of rotation coupling bodies 31 a and 31 b of the rotation coupling portion 31 </ b> A in the end link member 5 on the proximal end side.

  The pair of rotary coupling bodies 31a and 31b are bent by bending, and the mutual interval between the portions connected to the rotation support member 11 is wider than the mutual interval between the portions fixed to the bending portion 30. ing. And the reduction mechanism 51 is arrange | positioned in the part with a large mutual space | interval between a pair of rotation coupling bodies 31a and 31b. The speed reduction mechanism 51 is fixed to the rotation support member 11.

  The speed reduction mechanism 51 is composed of, for example, a planetary gear mechanism, and has an input shaft 51a and an output shaft 51b on the same axis. The input shaft 51a and the output shaft 51b are on the same axis as the central axis O1 of the rotational pair of the link hub 2 on the base end side and the end link member 5 on the base end side. The input shaft 51a and the output shaft 51b are rotatably supported on the housing of the speed reduction mechanism 51 by bearings 72 and 73, respectively.

  An input shaft 51a of the speed reduction mechanism 51 protrudes outward through the outer rotary coupling body 31a, and a driven timing pulley 55 of the belt-type power transmission mechanism 53 is rotatably attached to the tip thereof. . The input shaft 51a is rotatably supported by the outer rotary coupling body 31a by a bearing 71. A spacer 74 is interposed between the housing of the speed reduction mechanism 51 and the outer rotary coupling body 31a.

A flange 75 is fixed to the tip of the output shaft 51 b of the speed reduction mechanism 51, and a cylindrical member 76 is fixed to the outer periphery of the flange 75. The cylindrical member 76 extends inwardly through the inner diameter hole 77 of the rotation support member 11, and a tip end surface thereof is coupled to the inner rotation coupling body 31 b by a plurality of bolts 78.
Others are the same as the fourth embodiment.

  Thus, by arranging the speed reduction mechanism 51 between the pair of rotary coupling bodies 31a and 31b, the speed reduction mechanism 51 can be installed without projecting radially outward, and a more compact configuration can be realized. . In addition, if the speed reduction mechanism 51 is disposed between the pair of rotation coupling bodies 31a and 31b, the speed reduction mechanism 51 has a structure for connecting the pair of rotation coupling bodies 31a and 31b, which is advantageous in improving rigidity.

  As mentioned above, although the form for implementing this invention based on the Example was demonstrated, embodiment disclosed here is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 ... Parallel link mechanism 2 ... Base end side link hub 3 ... Front end side link hub 4 ... Link mechanism 5 ... Base end side end link member 6 ... End side end link member 7 ... Central link member 10 ... Base end member 10a ... through hole 11 ... rotation support member 30 ... curved portions 31A, 31B ... rotation connecting portions 31a, 31b ... rotation connecting body 50 ... position control actuator 50a ... output shaft 51 ... deceleration mechanism O1 ... on the base end side Center axis PA of rotation pair of link hub and base end side end link member PA: spherical link center QA of base end side: center axis of base link hub

Claims (7)

The link hub on the distal end side is connected to the link hub on the proximal end side through three or more sets of link mechanisms so that the posture can be changed, and each link mechanism includes the link hub on the proximal end side and the link hub on the distal end side. End link members on the base end side and the tip end side, one end of which is rotatably connected to the link hub, and a center on which both ends are rotatably connected to the other ends of the end link members on the base end side and the tip end side, respectively. A posture control actuator that has two or more link mechanisms out of the three or more link mechanisms and arbitrarily changes the posture of the distal link hub with respect to the proximal link hub. In the link actuating device provided with
The link hub on the base end side has a base end member that supports the link mechanisms,
With respect to the base end member, a central axis of a rotation pair of the base end side link hub and the base end side end link member and an output shaft of the attitude control actuator are arranged on opposite sides. A link actuating device characterized in that: 2. The link actuating device according to claim 1, wherein the base-side link hub is provided so as to protrude from the base end member toward the front end side and rotatably supports the base end-side end link members. A rotation support member of
The link actuating device, wherein the output shaft of the attitude control actuator is parallel to an arrangement surface of the plurality of rotation support members in the base end member.   3. The link actuating device according to claim 1, wherein the base end side link hub projects from the base end member to the front end side, and each base end side end link member is freely rotatable. A central axis of a rotation pair of the base end side link hub and the base end side end link member is an arrangement of the plurality of rotation support members in the base end member. Link actuator that is parallel to the surface.   4. The link operating device according to claim 1, wherein the base end member has a through hole in a central portion of the plurality of rotation support members.   The link actuator according to any one of claims 1 to 4, wherein the attitude control actuator is disposed inward with reference to an output shaft thereof. 6. The link actuating device according to claim 5, wherein a central axis of each rotation pair of said proximal end side link hub and said proximal end side end link member, and said proximal end side end link member and said central link. The point at which the central axis of each rotation pair of the member intersects is referred to as the spherical link center on the base end side, passes through the center of the spherical link on the base end side, and the link hub on the base end side and the end link on the base end side When a straight line that intersects with the central axis of each rotating pair of members at right angles is referred to as the central axis of the link hub on the base end side,
The output shaft of the attitude control actuator is a plane formed by the central axis of the rotation pair of the base end side link hub and the base end side end link member, and the central axis of the base end side link hub In contrast, a link actuating device arranged offset in parallel.   7. The link actuating device according to claim 1, wherein the base end side end link member is provided at a curved portion bent at an arbitrary angle and at one end of the curved portion. A rotation connecting portion composed of a pair of rotary connecting bodies arranged at intervals, and the base end side end link between the pair of rotary connecting bodies by decelerating the rotational power of the attitude control actuator A link operating device in which a speed reduction mechanism for transmitting to a member is arranged.

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