JP5217482B2 - Joint structure of fiber reinforced plastic link structure - Google Patents

Description

  The present invention relates to a joint structure of a link structure suitable for use in a robot or the like capable of transmitting high torque from drive parts such as a motor and a reduction gear in a link structure made of FRP (fiber reinforced plastic).

  Robots, especially robots that move like human hands and feet, have little time to move at a constant speed, and most of the time is accelerated and decelerated. When accelerating or decelerating, it is necessary to transmit torque from a driving source such as a motor or a speed reducer to the basic structure. Moreover, it is necessary to have a structure that can repeatedly transmit this torque. Further, when the link structure collides with the surroundings or falls due to an unexpected movement other than the normal operation, a torque larger than usual may be generated. Further, as the performance of the robot improves in the future, it is required for the link structure to transmit a larger torque.

  When the basic structural part is made of metal, it is common to produce the structural part with a metal integral structure and attach the drive source directly.

  On the other hand, a robot is required to have a basic structural portion that is lightweight and highly rigid from the viewpoints of improvement in operability and vibration suppression, miniaturization of a drive source, and the like. Therefore, lightweight and high-rigidity FRP has been adopted for the basic structural portion. In the FRP link structure, as in the case of metal for torque transmission, if the drive source is fixed directly to the FRP using bolts, nuts, etc., the necessary dimensional accuracy is difficult to obtain, and the required dimensional accuracy Even if it can be produced, when it is repeatedly used, there is a problem that the FRP is worn and the dimensional accuracy is deteriorated. Therefore, when attaching a drive source to a link structure made of FRP, a method of arranging a metal in a joint portion has been used (Patent Document 1).

In Patent Document 1, in order to transmit a large torque, a metal mounting seat for attaching a drive source or the like to a joint portion and a metal thin plate on an arm portion are connected by a method such as welding, and the inside and outside of the metal The hybrid structure is covered with FRP. However, because of the hybrid structure, the weight is heavy and the structure becomes complicated.
JP-A-10-202561

  Therefore, an object of the present invention is to provide a joint structure of a link structure made of FRP that is lightweight and highly rigid and capable of transmitting a large torque.

The present invention for solving the above-described problems has the following configuration. That is,
(1) In the arm portion configured link structure from fiber-reinforced plastic having a joint on both ends of a parallel two rotation center shaft provided on the joint portion of the both end, the arms, the the surface B facing the plane perpendicular to the two rotation center axis, are connected from one of the rotation center axis to an end of the surface B along a direction toward the other of the rotation center axis, parallel to said rotation axis A surface A that faces the flat surface, the joint portion faces the plane perpendicular to the central axis of rotation, and extends from the surface B, and the flange surface D rises at an angle with the surface C. becomes a, the flange surface D has a cylindrical surface E centered on the rotational center axis, the surface F to be connected to the end portion of the end portion and the surface a of the cylindrical surface E, collar space capable of attaching the metal mounting seat having a section that the surface C Is formed in a portion surrounded by the surface E and surface F Rutotomoni, articulated structure of the metal mounting seat said surface C, the link is bonded to the surface E and surface F structure.

  (2) The link structure according to claim 1, wherein a metal mounting seat bonded to the surface C, the surface E, and the surface F is attached to a portion surrounded by the surfaces C, E, and F. Joint structure.

  (3) The joint structure of the link structure used in an industrial robot.

(4) The joint structure of the link structure used for a service robot.
It is.

In configured link structure from fiber-reinforced plastic having a joint on both ends of the arm portions are parallel two rotation center shaft provided on the joint portion of the both ends, the arms, the two the surface B facing the plane perpendicular to the rotation center axis, are connected from one of the rotation center axis to an end of the surface B along a direction toward the other of the rotation center axis, and a plane parallel to the central axis of rotation it has opposing surfaces a, joint has a flange surface D which rises with plane C and the plane C and the angle formed by extending from the surface B with facing the plane perpendicular to the central axis of rotation becomes Te, the flange surface D has a face F that connects the cylindrical surface E centered on the rotation center axis, an end portion of the end portion and the surface a of the cylindrical surface E, has a collar The space where the metal mounting seat can be mounted is the surface C, surface E. Is formed on a portion surrounded by and surface F Rutotomoni, the metal mounting seat said surface C, since it is bonded to the surface E and surface F, the torque from the driving source such as a metal mounting seat disposed in the space Is input, the load transmitted from the metal mounting seat to the FRP can be handled not only on the surface C and the surface E of the FRP but also in the out-of-plane direction of the surface F, so that a large torque can be transmitted. It becomes possible.

  When the link structure according to the present invention is applied to a joint structure of a robot member such as an industrial robot or a service robot, it is possible to realize a structure that is light and highly rigid and can transmit a large torque. It becomes.

Link structure according to the present invention, in the link structure composed of fiber-reinforced plastic having a joint on both ends of the arm portions, two of the rotation center shaft provided on the joint portion of the both ends are parallel , the arm portion is connected to an end portion of the surface B along the surface B facing the plane perpendicular to the two rotation center axis, in a direction toward the other rotation center axis from one of the rotation center axis, A surface A that faces a plane parallel to the rotation center axis; and a joint C that faces the plane perpendicular to the rotation center axis and extends from the surface B ; it has a flange surface D which rises at an angle, the flange surface D is a cylindrical surface E centered on the rotational center axis, the end and the surface F to be connected to the end of the surface a of the cylindrical surface E has, that attach the metal mounting seat having a collar Kill space, the plane C, is formed in a portion surrounded by the surface E and surface F Rutotomoni, the metal mounting seat is characterized in that it is bonded to the said surface C, surface E and surface F.

  As used herein, “arm part” refers to a part connected to a joint part. For example, two joint parts at both ends are connected to transmit a load applied to the joint part, It is a part that plays a role such as incorporating parts.

  In addition, the term “surface facing a plane parallel to the rotation center axis” as used herein means, for example, a plane parallel to a plane parallel to the rotation center axis when the facing surface is a plane. When the opposing surface is a curved surface, a case where the normal line of the plane parallel to the rotation center axis and the normal line at any point on the curved surface are parallel is exemplified. Furthermore, “a surface facing a plane perpendicular to the rotation center axis” means, for example, when the facing surface is a plane, a plane parallel to the plane perpendicular to the rotation center axis, and facing the plane. When the surface is a curved surface, a case where the normal line of the plane perpendicular to the rotation center axis is parallel to the normal line at any point on the curved surface is exemplified.

  In the joint structure of the link structure according to the present invention, a metal mounting seat bonded to the surfaces C, E, and F is attached to a portion surrounded by the surfaces C, E, and F. be able to. By providing the metal mounting seat, it is possible to mount the drive component or the like to the link structure with high accuracy. Moreover, as a method of arranging the metal mounting seat on the FRP, not only adhesion but also mechanical joining such as bolts and rivets may be used in combination.

  The scope of application of the link structure according to the present invention is not particularly limited, and is preferably used for a structural part of an industrial robot or a service robot. In particular, when used for the arm and leg of a service robot, it is particularly effective for the operability and vibration control of the robot as described above. The industrial robot here refers to a welding robot, an assembly robot, or the like that is generally used in a production line. Service robots are all robots used for housework such as cleaning, nursing, rescue and entertainment.

  Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the drawings.

  The link structure of the present invention is composed of FRP and metal. FRP refers to a resin layer reinforced with reinforcing fibers. Examples of reinforcing fibers include inorganic fibers such as carbon fibers and glass fibers, and reinforcing fibers made of organic fibers such as Kevlar fibers, polyethylene fibers, and polyamide fibers. Can be mentioned. Carbon fiber is particularly preferable in terms of lightness and rigidity. The form of the reinforcing fiber is preferably a unidirectional material from the viewpoint of rigidity, but it is also preferable to use a cloth material from the viewpoint of formability. Short fibers can also be used. Examples of the matrix resin of the FRP layer include thermosetting resins such as epoxy resins, unsaturated polyester resins, vinyl ester resins, phenol resins, and further, polyamide resins, polyolefin resins, dicyclopentadiene resins, polyurethane resins. A thermoplastic resin such as can also be used. When high mechanical properties are required, an epoxy resin can be preferably applied.

  Moreover, as a metal used for the joint structure of the link structure according to the present invention, iron-based materials, titanium alloys, light alloys such as aluminum alloys and magnesium alloys can be used. From the viewpoint of weight reduction, it is preferable to use a light alloy.

FIG. 1 shows a perspective view of a link structure according to an embodiment of the present invention. Joint portions 5 and 6 are arranged at both ends of the arm portion 4. The two rotation center axes 2 and 3 provided in the joint parts 5 and 6 are parallel, and the arm part 4 has a surface B facing the plane perpendicular to the two rotation center axes 2 and 3, Connected to the end of the surface B along the direction from the rotation center axis 2 to the other rotation center axis 3, has a surface A facing the plane parallel to the rotation center axes 2, 3, and the joint parts 5, 6 Has a surface C that is opposed to a plane perpendicular to the rotation center axes 2 and 3 and extends from the surface B, and a flange surface D that rises at a right angle from the surface C (rises at an angle of 90 °). The surface D has a cylindrical surface E centered on the rotation center axis, a surface F connected to the end of the cylindrical surface E and the end of the surface A, and the surfaces C, E and F A bonded metal mounting seat is provided.

  When a driving source or the like is connected to the metal mounting seat and torque is input from the driving source to the metal mounting seat, it is necessary to transmit the torque from the metal mounting seat to the FRP. At that time, torque is transmitted from the metal mounting seat to the surface C through an adhesive, but since not only the surface E but also the surface F is bonded, a load is also applied to the surface F in the out-of-plane direction. Since it becomes possible to take charge, it becomes possible to transmit a larger torque. In addition, as an adhesive used for adhering the metal mounting seat to the surfaces C, E, and F, urethane or epoxy adhesive can be used. An agent is preferably used.

  If the metal mounting seat has a simple circular shape, it is possible to transmit the torque generated by normal operation, but if it collides with the surroundings due to unexpected movement or falls, it is larger than usual. Torque is generated and it is difficult to transmit the torque. In order to transmit a large torque with a simple circular shape, it is necessary to increase the radius of the circular circle in order to increase the adhesion area with the surface C. In addition, there are various restrictions such as the space relationship with other parts.

  On the other hand, when the collar portion is provided on the metal mounting seat as in the present invention, there is little restriction on the space engagement with other parts, and the increase in weight can be minimized. Further, not only the torque that can be transmitted is increased by the increase in the adhesion area between the metal mounting seat and the surface C, but also the load can be transmitted in the out-of-plane direction of the surface F. It is possible to reduce the stress itself generated in. By reducing the stress generated between the metal mounting seat and the surface C, durability when repeated torque is input is also improved.

  2 and 3 are perspective views of a metal mounting seat used in the link structure shown in FIG. Thus, the thickness and area of the collar portion of the metal mounting seat to be bonded to the surface F may be determined as appropriate depending on the magnitude of torque that needs to be transmitted.

It is a perspective view which shows an example of the link structure which concerns on this invention. It is a perspective view of the metal attachment seat of the link structure shown in FIG. It is a perspective view of the metal attachment seat of the link structure shown in FIG.

Explanation of symbols

1: Link structure 2, 3: Rotation center axis 4: Arm
5, 6: Joint part
7, 8: Metal mounting base 10, 11, 12, 13: Collar A, B, C, D, E, F: Surface

Claims (4)

In configured link structure from fiber-reinforced plastic having a joint on both ends of the arm portions are parallel two rotation center shaft provided on the joint portion of the both ends, the arms, the two the surface B facing the plane perpendicular to the rotation center axis, are connected from one of the rotation center axis to an end of the surface B along a direction toward the other of the rotation center axis, and a plane parallel to the central axis of rotation it has opposing surfaces a, joint has a flange surface D which rises with plane C and the plane C and the angle formed by extending from the surface B with facing the plane perpendicular to the central axis of rotation becomes Te, the flange surface D has a face F that connects the cylindrical surface E centered on the rotation center axis, an end portion of the end portion and the surface a of the cylindrical surface E, has a collar The space where the metal mounting seat can be mounted is the surface C, surface E. Is formed on a portion surrounded by and surface F Rutotomoni, articulated structure of the metal mounting seat said surface C, the link is bonded to the surface E and surface F structure. The joint structure of the link structure according to claim 1, wherein a metal mounting seat bonded to the surface C, the surface E, and the surface F is attached to a portion surrounded by the surface C, the surface E, and the surface F. . The joint structure of the link structure according to claim 1 or 2, which is used for an industrial robot. The joint structure of the link structure according to claim 1 or 2, which is used for a service robot.