Robot arm, manufacturing method thereof and robot

Abstract

The invention provides a robot arm, a method for manufacturing the same, and a robot, which can maintain strength, realize light weight and reduce production cost. A robot arm (1) is provided with an arm main body (2) and a mounting interface section (3) provided on the arm main body (2), at least a part of the outer surfaces of the arm main body (2) and the mounting interface section (3) are made of resin, and a first component (21) having one mounting interface section (3) and a part of the arm main body (2) and a second component (20) having one mounting interface section (3) and a part of the arm main body (2) are integrally formed by being non-detachably joined to each other. The second component (20) is provided with the other mounting interface part (3) and a part of the arm main body (2), and the non-separable joint part is provided with a concave-convex structure for preventing movement in the long axis direction or rotation around the long axis.

Description

[0001] This application is a divisional application of a Chinese invention patent with an application date of July 22, 2019, a priority date of July 25, 2018, an application number of "201910661539.4", and an invention name of "Robot arm, its manufacturing method, and robot". Technical Field

[0002] The invention relates to a robot arm, a manufacturing method thereof and a robot. Background Art

[0003] Generally, the arm of an industrial robot is made of metal such as aluminum alloy in order to reduce weight while maintaining strength (see, for example, Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2013-018058 Summary of the invention

[0007] Problem that the invention aims to solve

[0008] However, metal robot arms have limitations in terms of weight reduction, and in order to manufacture the mounting surface of the actuator with high precision, the mounting surface needs to be processed with high precision, which disadvantageously increases the production cost.

[0009] The present invention is made in view of the above situation, and its object is to provide a robot arm and a manufacturing method thereof and a robot that can maintain strength while further achieving lightness and reduce production costs.

[0010] Solutions for solving problems

[0011] One embodiment of the present invention is a robot arm, which has a long cylindrical arm body and mounting interface parts fixed on both sides of the arm body and used for mounting on other components, at least a portion of the outer surface of the arm body and the mounting interface part is made of resin, a first part and a second part are joined to each other, the first part has one mounting interface part and a part of the arm body, and the second part has another mounting interface part and another part of the arm body.

[0012] According to this scheme, at least a part of the arm body and the mounting interface part constituting the robot arm is made of resin, so that it can be significantly lightened compared with the conventional robot arm using metal materials. In this case, the shape of the mounting interface part is provided at both ends of the long cylindrical arm body, and it cannot be formed at one time using a forming mold.

[0013] In contrast, according to this solution, the first part and the second part, which are divided along the length direction of the arm body and whose internal space is open in at least one direction, can be simply formed by a forming die, and can be easily manufactured by joining the formed first part and the second part. Thus, the production cost can be reduced. By simply changing the length of the arm body, various arm variations can be easily configured.

[0014] In the above scheme, each of the mounting interface parts may further include: a metal component constituting a mounting surface for mounting on the other component; and a resin connecting part embedded in and connected to the arm body in a state where at least the mounting surface of the metal component is exposed.

[0015] According to this structure, the metal parts are pre-machined with high precision and respectively embedded in the resin of the mounting interface parts at both ends of the arm body, thereby realizing a robot arm with two mounting surfaces that are not machined but aligned with high precision, and can keep the production cost low.

[0016] In the above scheme, the metal component can also be formed into an annular plate shape having a central hole penetrating in the center along the plate thickness direction, and the connecting portion has an internal space, which is connected to the inner hole of the arm body and is open to the outside in the central hole of the metal component.

[0017] According to this structure, the internal space can be connected to the mounting surfaces at both ends through the inner hole of the arm body.

[0018] In the above aspect, the mounting surface may be arranged in parallel with the long axis of the arm body.

[0019] According to this configuration, a robot arm is configured that rotates around the central axis of the metal member at one end of the arm body.

[0020] In the above aspect, the metal component may further include a through hole penetrating in the plate thickness direction and allowing the mounting screw to pass therethrough, and the mounting surface and the back side of the mounting surface may expose the mounting screw support surface around the through hole and be buried in the resin constituting the connection portion.

[0021] According to this structure, when the robot arm is fixed to a mounted body such as an actuator using a mounting screw that passes through a through hole in a metal component provided in the mounting interface, the surface of the metal component is exposed as a supporting surface for the mounting screw, so that the mounting screw can be tightened without resin being interposed between the head of the mounting screw and the mounted body, and the mounting screw can be prevented from loosening due to repeated stress, thereby further effectively fixing the robot arm.

[0022] In the above aspect, the resin constituting each of the mounting interface portions and each of the metal members may be fixed to each other by fitting a recessed portion provided in one of them with a protruding portion provided in the other.

[0023] According to this structure, when the metal component is embedded in the resin constituting the mounting interface, the concave portion and the convex portion are engaged, thereby preventing the metal component from being displaced relative to the resin even when an external force is applied. In this case, the concave portion and the convex portion formed by mechanical processing can be engaged, or the molten resin can be made to flow into the concave and convex formed on the metal component by chemical treatment and engaged.

[0024] In the above solution, the two metal parts can also be electrically conductive.

[0025] According to this configuration, it is possible to easily perform electrical grounding of electric machine parts and the like attached to the tip of the robot arm.

[0026] In the above aspect, the metal component may be made of a metal material having higher corrosion resistance than aluminum in combination with carbon fiber.

[0027] According to this structure, even when a resin containing carbon fiber is used, corrosion of metal parts can be prevented and durability can be improved.

[0028] In the above solution, the first part and the second part may also have the same shape.

[0029] According to this structure, it is sufficient to mold two parts of one type and join them to each other, and the production cost can be reduced by reducing the types of parts.

[0030] In the above aspect, the second part may be a fourth part obtained by joining a third part having the same shape as the first part and a portion of the arm body extending from the third part.

[0031] According to this structure, by making the first part and the third part have the same shape, two parts of the same type are formed and joined together, and the production cost can be reduced by reducing the types of parts. The length of the arm body can be adjusted by adjusting the length of the fourth part joined to the third part.

[0032] In the above scheme, the fourth part may also be a cylinder made of resin with a uniform cross section.

[0033] According to this structure, the production cost of the robot arm can be reduced by using the fourth part that can be easily formed. By making the fourth part a cylinder with a uniform cross section, the arm body with different lengths can be easily formed.

[0034] In the above solution, the fourth part may also be a cylinder having a uniform cross-section formed by coating the outer surface of a metal tube with resin.

[0035] According to this structure, the production cost of the robot arm can be reduced by using the fourth part that can be easily formed. By making the fourth part a cylinder with a uniform cross section, it is possible to easily form arm bodies of different lengths. By arranging a metal pipe on the inner surface, the rigidity of the robot arm can be improved. Since at least a part of the surface is covered with a resin that is softer than metal, when it comes into contact with a person, the force applied to the human body can be reduced more than in the case of metal.

[0036] In the above scheme, the first part and the second part can also be joined by a mechanical joining element.

[0037] According to this structure, the bonding strength can be improved compared to the case of bonding with an adhesive, and electrical conduction can be easily achieved by bonding the first component and the second component. As the mechanical bonding element, for example, bolts or rivets can be used.

[0038] In the above aspect, the resin constituting the arm body and the mounting interface portion may also have flame retardancy such that even if arranged in a vertical direction and ignited for 10 seconds, the flame duration is less than 10 seconds and cannot burn more than 127 mm.

[0039] According to this structure, the self-extinguishing property of the robot arm can be ensured.

[0040] In the above scheme, the outer surface of the resin constituting the arm body and the mounting interface portion can also be coated with the following flame-retardant coating: even if arranged in a vertical direction and ignited for 10 seconds, the flame duration is less than 10 seconds and cannot burn more than 127 mm.

[0041] According to this structure, the self-extinguishing property of the robot arm can be ensured by the highly flame-retardant paint.

[0042] Another embodiment of the present invention is a method for manufacturing a robot arm, which has mounting interface portions for mounting on other components at both ends of a long cylindrical arm body. In the method for manufacturing the robot arm, at least a portion of the molded outer surface is a first part made of resin, the first part having an mounting interface portion and a portion of the arm body, and at least a portion of the molded outer surface is a second part made of resin, the second part having another mounting interface portion and another portion of the arm body. The first part and the second part after molding are joined in a state where they are positioned relative to each other.

[0043] In the above solution, the first part and the second part may also be formed by injection molding or stamping.

[0044] Another embodiment of the present invention is a method for manufacturing a robot arm, which has mounting interface portions for mounting on other components at both ends of a long cylindrical arm body. In the method for manufacturing the robot arm, a first part and a third part of the same shape whose outer surfaces are at least partially formed as resin, the first part and the third part having the mounting interface portion and a portion of the arm body, a cylindrical fourth part of a portion of the arm body extending from the first part is formed, and the fourth part is arranged between the formed first and third parts and joined when they are positioned relative to each other.

[0045] In the above scheme, the first part, the third part, and the fourth part may also be formed by injection molding or stamping.

[0046] In the above scheme, after the first part, the third part and the fourth part are fixed in a positioned state in the same forming mold, they can be integrally joined in a manner to form a final shape of the robot arm.

[0047] Another aspect of the present invention is a robot including any of the above-mentioned robot arms.

[0048] In the above solution, there may be more than two robot arms.

[0049] In the above solution, the mounting interface portion of each of the robot arms may also be of the same shape, and the arm body of each of the robot arms may have different lengths.

[0050] In the above solution, the plurality of robot arms may also be of the same length.

[0051] Effects of the Invention

[0052] According to the present invention, it is possible to further reduce weight while maintaining strength, and to reduce production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 It is a perspective view showing a robot arm according to one embodiment of the present invention.

[0054] Figure 2 Viewed from the mounting surface Figure 1 A stereoscopic view of the robot arm.

[0055] Figure 3 Viewed from the mounting surface Figure 1 Figure 1. A diagram of a robotic arm.

[0056] Figure 4 yes Figure 1 Top view of the robot arm.

[0057] Figure 5 yes Figure 1 Side view of the robotic arm.

[0058] Figure 6 Yes means Figure 1 A longitudinal section view of the robot arm.

[0059] Figure 7 yes Figure 1 A partial enlarged longitudinal sectional view of the mounting interface portion of the robot arm.

[0060] Figure 8 This is a flowchart showing a method for manufacturing a robot arm according to one embodiment of the present invention.

[0061] Fig. 9 It means that Figure 1 A front view of the robot arm assembled to the joint axis portion of the robot with a reducer.

[0062] Fig.10 Yes means Fig. 9 A stereoscopic view of the joint shaft portion.

[0063] Fig.11 yes Figure 7 An enlarged longitudinal sectional view of part A.

[0064] Fig.12 Yes means Fig.11 A perspective view of a modified example of a metal plate.

[0065] Fig.13 Yes means Figure 1 A longitudinal sectional view of a modified example of a method for joining an end part and a central part of a robot arm.

[0066] Fig.14 Yes means Figure 1 A longitudinal cross-sectional view of an example of a method for electrically connecting metal plates of a robot arm to each other.

[0067] Fig.15 Yes means Figure 1 A perspective view of a modified example of a robot arm.

[0068] Fig.16 Yes means Figure 1 A perspective view of another variation of the robot arm.

[0069] Fig.17 Yes means Figure 1 A perspective view of another variation of the robot arm.

[0070] Fig.18 Yes means Figure 1 A perspective view of another variation of the robot arm.

[0071] Description of reference numerals:

[0072] 1: Robotic Arm

[0073] 2: Arm body

[0074] 2a: Inner hole

[0075] 3: Install the interface

[0076] 5: Metal plates (metal parts)

[0077] 5a: Mounting surface

[0078] 6: Central hole

[0079] 7: Through hole

[0080] 9: Mounting screws

[0081] 10: Cover parts

[0082] 15: convex part

[0083] 16: Concave

[0084] 20: The Second Part

[0085] 21, 22: End parts (first part, third part)

[0086] 23: Central part (fourth part)

[0087] 100: Robot DETAILED DESCRIPTION

[0088] Hereinafter, a robot arm 1 and a method for manufacturing the same, and a robot 100 according to an embodiment of the present invention will be described with reference to the drawings.

[0089] like Figures 1 to 5 As shown, the robot arm 1 of the present embodiment includes: a cylindrical tubular arm body 2; and two mounting interface portions 3 provided at both ends of the arm body 2 in the longitudinal direction.

[0090] The arm body 2 is made of resin.

[0091] The mounting interface portion 3 includes a resin connection portion 4 connected to the arm body 2 and a flat metal plate (metal member) 5 embedded in the resin constituting the connection portion 4. The connection portion 4 is arranged at a position shielding the inner hole 2a of the arm body 2 at both ends and has a substantially truncated cone shape extending in a direction perpendicular to the long axis of the arm body 2.

[0092] The metal plate 5 is disposed in parallel with the long axis of the arm body 2 at a portion corresponding to the bottom surface of the truncated cone-shaped connection portion 4 , and is embedded in the resin constituting the connection portion 4 by, for example, insert molding.

[0093] like Figure 2 as well as Figure 3 As shown, the metal plate 5 is formed in an annular plate shape having a central hole 6. The metal plate 5 is provided with a plurality of through holes 7 penetrating in the plate thickness direction at intervals in the circumferential direction.

[0094] like Figure 6 As shown, each connecting part 4 is hollow, and the inner hole of the connecting part 4 is connected to the inner hole 2a of the arm body 2 connected to the side wall of the connecting part 4. Thus, the inner hole 2a of the arm body 2 is bent in the connecting part 4 and opens to the central hole 6 of the two metal plates 5. Figure 6 In the embodiment, the outer peripheral surface of the arm body 2 is fitted with the inner peripheral surfaces of the first part 21 and the third part 22 , but the outer peripheral surfaces of the first part 21 and the third part 22 may be fitted with the inner peripheral surface of the arm body 2 .

[0095] The metal plate 5 has one surface in the plate thickness direction as a mounting surface 5a, and the mounting surface 5a is entirely exposed.

[0096] like Figure 7 As shown, the other side of the metal plate 5 in the plate thickness direction is covered with the resin constituting the connection portion 4 while partially exposing the peripheries of the through holes 7. The surface of the metal plate 5 exposed around the through holes 7 is made of a resin having a thickness greater than that of the mounting screws (see Fig.10 ) The outer diameter of the head of 9 is exposed in a slightly larger manner and functions as a supporting surface for the mounting screw 9 inserted into the through hole 7.

[0097] The through hole 7 arranged at a position overlapping with the arm body 2 is blocked by covering the through hole 7 with the resin constituting the connection part 4 so that the metal plate 5 is not exposed as a support surface. With such a structure, when a positioning pin is inserted, it is possible to prevent the positioning pin from falling off due to the movement of the robot 100, etc.

[0098] The mounting surface 5a of the metal plate 5 is arranged at a position protruding from the resin constituting the connection portion 4. Furthermore, the mounting surfaces 5a of the metal plates 5 of the two connection portions 4 are arranged in the same plane.

[0099] The connection portion 4 is provided with an opening 8 at a position different from the central hole 6 of the metal plate 5 so as to open the space in the connection portion 4 to the outside. Figure 1 In the embodiment, the opening 8 is provided on the opposite side of the central hole 6, but the invention is not limited thereto and may be provided on the side surface of each connecting portion 4. The opening 8 can be closed by a cover member 10 described below.

[0100] In this embodiment, if Figures 1 to 6 As shown, the robot arm 1 is formed by mutually joining two end parts (first part, third part) 21, 22, the two end parts (first part, third part) 21, 22 having a mounting interface portion 3 on one side and a part of the arm body 2 connected to the mounting interface portion 3, and a simple cylindrical central part (fourth part) 23, and the central part (fourth part) 23 is arranged between the two end parts 21, 22 and constitutes the central part of the arm body 2. Here, the second part 20 is constituted by the end part 21 on one side and the central part 23.

[0101] A method for manufacturing the robot arm 1 of the present embodiment configured as described above will be described below.

[0102] like Figure 8 As shown, in the manufacturing method of this embodiment, two end parts 21, 22 are formed (step S1), a central part 23 is formed (step S2), the two end parts 21, 22 are arranged at both ends of the central part 23 and the three parts 21, 22, 23 are joined to each other (step S3).

[0103] The end parts 21 and 22 can be easily manufactured by resin insert molding while positioning the metal plate 5 manufactured with high precision by machining or the like in the molding die. That is, the end parts 21 and 22 can be easily molded by injection molding or press molding using the molding die.

[0104] Here, since the robot arm 1 of this embodiment has the mounting interface parts 3 at both ends of the cylindrical arm body 2, the inner hole 2a of the arm body 2 is shielded at both ends by the connecting parts 4. Therefore, the entire robot arm 1 cannot be molded at one time in the molding method using a molding die.

[0105] In contrast, in the present embodiment, the robot arm 1 is divided into the central part 23 and the two end parts 21 and 22, so that the inner hole 2a of the arm body 2 and the inner hole of the connecting part 4 are opened in one direction in the end parts 21 and 22. That is, by studying the division structure of the forming mold, the end parts 21 and 22 can be easily manufactured using the forming mold.

[0106] Since the central piece 23 is a simple cylindrical member, it can be easily formed by drawing or extrusion.

[0107] The use of parts having the same shape as the two end parts 21 and 22 can reduce the types of parts used. Reducing the types of parts used can facilitate parts management and reduce the types of molding dies, which can effectively reduce production costs.

[0108] There is also the advantage that a simple cylindrical member is used as the central member 23 connecting the two end members 21 and 22 of the same shape, so that the length in the long axis direction can be easily adjusted, and robot arms 1 of different lengths can be easily manufactured. Thus, robot arms 1 of various lengths can be constructed in which only the length of the arm body 2 is different.

[0109] Moreover, in step S3, after the two end parts 21, 22, especially the surfaces on one side of the mounting surfaces 5a of the two metal plates 5 which will become the end parts 21, 22, are fixed in the same plane with high precision using a clamp, etc., they are integrally joined in a manner to form the final shape of the robot arm 1 according to any joining method such as injection molding or stamping, thereby manufacturing the robot arm 1 of this embodiment having two mounting interface parts 3 at both ends of the arm body 2.

[0110] According to the robot arm 1 of the present embodiment manufactured in this manner, since it is almost entirely made of resin, it is possible to significantly reduce the weight compared to a case where the robot arm 1 is made of metal such as aluminum alloy.

[0111] Since the metal plates 5 having a high-precision structure are manufactured by insert molding, the mounting surfaces 5a of the two metal plates 5 can be arranged with high precision without machining. Thus, machining is not required, and production costs can be reduced.

[0112] In particular, there is an advantage that, since the mounting surface 5 a of the metal plate 5 is made to protrude from the resin constituting the connection portion 4 , the resin does not become an obstacle when the robot arm 1 is mounted on the speed reducer output shaft 110 .

[0113] Moreover, if Fig. 9 as well as Fig.10 As shown, by fixing such a robot arm 1 to the speed reducer output shaft 110 or the like of the robot 100 , the joint axis of the robot 100 can be easily configured.

[0114] In this case, the mounting screw 9 is passed through the through hole 7 provided in the metal plate 5 and fastened to the threaded hole of the speed reducer output shaft 110 , so that the head of the mounting screw 9 can be pressed against the surface opposite to the mounting surface 5 a of the metal plate 5 , i.e., the supporting surface.

[0115] That is, when there is resin between the head of the mounting screw 9 and the reducer output shaft 110, sufficient tightening cannot be performed, so the robot 100 performs repeated movements, and there is a risk of the mounting screw 9 loosening. However, in the present embodiment, since only the metal plate 5 is arranged between the head of the mounting screw 9 and the reducer output shaft 110, it is possible to tighten with sufficient tightening force, and there is an advantage of being able to effectively prevent the mounting screw 9 from loosening.

[0116] However, it is necessary to pay attention so that the metal plate 5 itself does not peel off from the resin member of the connecting portion 4 due to the load. Fig.11 As shown, if this is taken into consideration, it is preferable to provide a convex portion 15 protruding in the radial direction at a position spaced apart from the mounting surface 5a in the thickness direction on the side surface of the metal plate 5. By so configuring, the cross-sectional shape of the metal plate 5 is formed in a concave-convex shape in the longitudinal direction, so that the convex portion 15 can be hung on the connecting portion 4, and the metal plate 5 will not be peeled off without damaging the resin component of the connecting portion 4.

[0117] The structure in which the convex portion 15 is provided on the metal plate 5 is described as an example, but instead, a concave portion 16 recessed in the radial direction may be provided in the side surface of the metal plate 5 at a midway position in the thickness direction. Fig.12 As shown, a radially recessed concave portion 16 may be provided at one or more circumferential locations. Thus, even if torque acts on the metal plate, positional misalignment with the resin constituting the connection portion can be prevented. In order to further increase strength and enhance rigidity, a structural adhesive may be used in combination.

[0118] According to the robot arm 1 of the present embodiment, the arm body 2 is formed into a hollow tubular shape having an inner hole 2a, the metal plate 5 is formed into a ring plate shape having a central hole 6, and the connecting portion 4 is formed hollow in such a manner that the inner hole 2a opens toward the central hole 6, so that a space from the mounting surface 5a of one mounting interface portion 3 through the inner hole 2a of the arm body 2 to the mounting surface 5a of another mounting interface portion 3 is formed in the robot arm 1. As a result, there are advantages that a line body such as a cable can be passed through the space, and the line body can be wired without being exposed to the outside.

[0119] An opening portion 8 is provided on the side opposite to the central hole 6 of the metal plate 5 so as to open the space in the connecting portion 4 to the outside. Therefore, when the mounting surface 5a is fixed to the mounted body such as the actuator 120, the internal space of the robot arm 1 can be approached through the opening portion 8 while the central hole 6 of the metal plate 5 is blocked, which has the advantage of facilitating the fixing operation and wiring operation of the line body.

[0120] like Fig.10 As shown in FIG. 1 , when the cover member 10 for closing the opening 8 is fixed to the connecting portion 4 by screws, as shown in FIG. Figure 7 As shown, a metal plate 12 formed into a ring-shaped plate is embedded in the central hole 14 connected to the molding port 8 on the connecting portion 4 side, and a threaded hole 13 is pre-set in the metal plate 12, so that the cover member 10 can be fixed in a manner that does not loosen. By firmly fastening the cover member 10, the strength of the robot arm 1 can be improved.

[0121] The through hole 7 that exposes the surface of the metal plate 5 serving as the supporting surface can be used when fixed to the reducer output shaft 110, etc. using the mounting screws 9 as described above, but the through hole 7 that overlaps with the arm body 2 and is sealed with resin can be used as a pin hole for engaging a positioning pin that is positioned circumferentially between the reducer output shaft 110.

[0122] As the robot arm 1 of this embodiment, an example of a robot arm manufactured in a state where the mounting surfaces 5a of the two metal plates 5 are positioned in the same plane is described, but alternatively, it can also be manufactured in a state where the mounting surfaces 5a of the two metal plates 5 are positioned parallel to each other.

[0123] In the present embodiment, a metal plate 5 which is an annular plate-shaped component having a central hole 6 and a plurality of through holes 7 around the central hole 6 is illustrated as a metal component, but alternatively, a plurality of gasket-shaped metal components having a single through hole 7 may be arranged around the central hole 6 and buried in the resin constituting the connecting portion 4.

[0124] In this embodiment, the arm body 2 made of resin is described, but instead, a thin-walled cylindrical member made of metal such as aluminum may be coated with resin on its surface. By using metal in combination, the rigidity of the arm body 2 can be increased, and by using metal and resin in combination, the amount of metal used can be reduced, thereby achieving weight reduction. By forming the outer surface with resin, the robot arm 1 can be formed with a relatively soft surface.

[0125] Preferably, the resin constituting the arm body 2 and the connecting portion 4 preferably has a flame duration of less than 10 seconds even if it is arranged in the vertical direction and ignited for 10 seconds, and has a flame retardancy that cannot burn more than 127 mm. In addition, the test piece ((125±5)×(13±0.5)×t) mm is directly mounted on the clamp, and the 10-second contact flame of a 20 mm flame is used twice. The burning time of each test piece is less than 10 seconds, the total burning time of five pieces is less than 50 seconds, and the burning + luminescence time of each test piece is less than 30 seconds. There is no burning to the clamp, and no ignition of the cotton arranged below the test piece occurs. According to this structure, there is the following advantage: even if the robot arm 1 is overheated for some reason, self-extinguishing properties can be guaranteed. Even if the flame retardant performance does not meet the conditions as described above and is at a slightly lower level, it is self-evident that the function of the robot arm 1 can be satisfied.

[0126] In addition to the case where the flame-retardant resin described above is used as the resin itself, even if the flame retardancy of the resin itself is low, a coating material having a higher flame retardancy than the resin may be applied to the entire outer surface of the resin.

[0127] As the resin, any thermosetting resin or thermoplastic resin can be adopted.

[0128] As the resin, any fiber-reinforced resin such as glass fiber-reinforced resin can be used. In glass fiber-reinforced resin, since the fiber is colorless and transparent, color can be added to the base material, thereby reducing the painting cost.

[0129] Preferably, when a resin containing carbon fibers is used as the resin, the carbon fibers are oriented in the long axis direction of the arm body 2, and the carbon fibers are arranged in contact with each other, and the carbon fibers are in contact with the metal plate 5. Thus, the metal plates 5 arranged at both ends of the robot arm 1 can be electrically connected to each other. That is, when an electric machine material such as an electric tool is mounted on the front end of the robot arm 1, the electric machine material can be electrically grounded without providing a separate ground wire.

[0130] Furthermore, when using a resin containing carbon fibers, the metal plate 5 embedded in the resin is preferably made of a metal material having higher corrosion resistance than aluminum for the combination with the carbon fibers. This can prevent corrosion of the metal plate 5 and improve durability.

[0131] The joining of the end parts 21, 22 and the central part 23 can be any joining method, but instead, as Fig.13 As shown, the cylindrical parts of the end parts 21 and 22 can also be fitted with the central part 23, and in the fitted part, the end parts 21 and 22 and the central part 23 are mechanically fixed by a shaft 24 penetrating in the radial direction and a fixing bolt 25. According to this structure, it is possible to prevent the end parts 21 and 22 and the central part 23 from falling off in the long axis direction or rotating around the long axis and being displaced from each other.

[0132] As a mechanical fixing method, mechanical combining elements such as bolts and rivets can be used. In this case, in order to prevent the support surface from being dented and strengthen the internal thread, it is preferred to use metal parts such as washers and spacers. Since bolts and rivets are metal, electrical conduction can be easily ensured.

[0133] As a mechanical fixing method, a key, a keyway, a spline connection, etc. that meshes in the circumferential direction may also be used. In order to further increase the strength and strengthen the rigidity, a structural adhesive may also be used in combination.

[0134] The end parts 21, 22 and the central part 23 are formed of a non-conductive resin. Fig.14 As shown, the metal plates 5 at both ends of the robot arm 1 may be connected to each other by using cables 26 so as to be electrically conductive.

[0135] In this embodiment, a simple cylindrical central part 23 is used to connect two end parts 21 and 22 of the same shape, but instead, as shown in FIG. Fig.15 As shown, the robot arm 1 can also be manufactured by dividing the arm body 2 in the center and directly joining two end parts 21, 22 of the same shape to each other.

[0136] like Fig.16 As shown, two types of end parts 21 and 22 of different lengths constituting a part of the arm body 2 are prepared, and the robot arm 1 can be manufactured by directly joining these end parts 21 and 22. In this case, it is possible to manufacture the robot arm 1 of three types of lengths by combining shorter end parts 21 and 22, combining longer end parts 21 and 22, and combining longer end parts 21 and shorter end parts 22, and various arm extension changes can be achieved. By preparing two or more types of end parts 21 and 22 of different lengths, more arm extension changes can be achieved.

[0137] The robot 100 of this embodiment may also include two or more of the above-mentioned robot arms 1. For example, the robot arms 1 described above may be used for the forearm and the upper arm of the robot 100, so that the robot 100 can be constructed with light weight and low cost. By using two or more robot arms 1 of the same length, the cost can be further reduced. By using two or more robot arms 1 of different lengths due to different lengths of the arm body 2, the robot 100 of various extension lengths can be constructed.

[0138] In this embodiment, the mounting interface portion 3 is provided at both ends of the arm body 2 so that the inner hole 2a of the arm body 2 is bent in an orthogonal direction, but instead, as the mounting interface portion 3, Fig.17 as well as Fig.18 As shown, the following mounting interface can also be used: having a mounting surface 5a extending in a direction perpendicular to the long axis of the arm body 2, and making the inner hole 2a of the arm body 2 open in the long axis direction. The longer the arm body 2 is, the more difficult it is to make a mold, so the structure of the present invention is effective.

[0139] As the robot arm 1, Figure 1 or Fig.17 As shown, at least one side of the two ends of the arm body 2 is provided with a mounting interface portion 3 that bends the inner hole 2a of the arm body 2 in an orthogonal direction, as shown in FIG. Fig.18 As shown, the arm body 2 has a mounting surface 5a extending in a direction perpendicular to the long axis, and the inner hole 2a of the arm body 2 is opened in the long axis direction. Figure 1 or Fig.17 The robot arm 1 shown is Fig.18 The robot arm 1 shown can more effectively utilize the segmentation structure of the present invention.

[0140] In this embodiment, as the robot arm 1, Figure 6 In the example, a robot arm is illustrated in which the end parts 21, 22 and the center part 23 overlap. The overlap amount can be any length as long as the arm strength can be ensured. However, in order for the line body to pass through the robot arm 1, the center hole 6 and the inner hole 2a must be connected.

Claims

1. A robot arm, characterized in that: The robot arm comprises an arm body and a mounting interface portion provided on the arm body. At least a portion of the outer surface of the arm body and the mounting interface portion is made of resin. The first part and the second part are integrally formed by being inseparably joined to each other, the first part having one of the mounting interface portions and a portion of the arm body, and the second part having another of the mounting interface portions and another portion of the arm body, The inseparable joint portion has a concave-convex structure that prevents movement in the longitudinal direction or rotation around the longitudinal axis.

2. A robot arm, characterized in that: The robot arm comprises an arm body and a mounting interface portion provided on the arm body. At least a portion of the outer surface of the arm body and the mounting interface portion is made of resin. The first part and the second part are integrally formed by being inseparably joined to each other, the first part having one of the mounting interface portions and a portion of the arm body, and the second part having another of the mounting interface portions and another portion of the arm body, The resin portion contains reinforcing metal inside.

3. A robot arm, characterized in that: The robot arm comprises an arm body and a mounting interface portion provided on the arm body. At least a portion of the outer surface of the arm body and the mounting interface portion is made of resin. The first part and the second part are integrally formed by being inseparably joined to each other, the first part having one of the mounting interface portions and a portion of the arm body, and the second part having another of the mounting interface portions and another portion of the arm body, The mounting interface portion includes: a mounting surface for mounting other components; and an opening portion provided at a position different from a central portion of the mounting surface.

4. The robot arm according to claim 1, characterized in that: The concavo-convex structure is also used with a structural adhesive.

5. The robot arm according to claim 3, characterized in that: A cover member for closing the opening is provided.

6. The robot arm according to any one of claims 1 to 5, characterized in that: The second part engages a third part and a fourth part extending a portion of the arm body of the third part, the third part having the other mounting interface portion and another portion of the arm body.

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