ROBOTIC ARM
FIELD
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Embodiments of the present disclosure generally relate to an industrial robot, and more specifically, to a robotic arm made of plastic material.
BACKGROUND
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Industrial robots are widely used in various industry fields. An industrial robot typically comprises a robotic arm formed by a plurality of axial joints, each joint including a casing and an actuator arranged therein, and a plurality of structural arms connecting the adjacent joints. An end effector may be fixed to an end flange of the robotic arm and are designed to perform various tasks. The casing of the joint and the structural arms are load bearing members and are designed with sufficient strength to withstand loads. Typically, these structural members are made of lightweight metals, such as aluminum alloys, to ensure sufficient structural strength.
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There is an increasing trend of using plastic material to replace the metal to construct these structural members. This may bring about a number of advantages. Since load bearing structural members of the robotic arm are made of plastic material, they can be manufactured via injection molding, which significantly reduces the manufacturing costs of the industrial robot, obviates need to painting their outer surfaces while it can ensure its lightweight.
SUMMARY
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Example embodiments of the present disclosure provide an arm body mainly made of plastic material, a robotic arm and an industrial robot with improved connection strength.
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In a first aspect of the present disclosure, there is provided an arm body for a robotic arm. The arm body comprises a body part made of plastic material and comprising a mounting opening; and a mounting interface provided at the mounting opening and comprising a flange portion made of the plastic material and extending radially inward from an inner wall surface of the body part to partially block the mounting opening, the flange portion comprising a plurality of holes circumferentially distributed around the mounting opening, and a plurality of metal members arranged within a respective hole of the plurality of holes, the metal member comprising a mounting hole configured to receive a screw fastener. With this arrangement, the connection strength at the mounting interface can be improved.
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In some embodiments, an inner or outer axial end surface of the flange portion with respect to an inner chamber of the body part forms an attaching surface configured to be connected to a second component of a robot. With this arrangement, components can be easily positioned and connected to the flange portion.
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In some embodiments, the metal member may extend in a direction parallel to a direction in which the mounting opening opens. With this arrangement, the metal member can be easily formed for example by insert molding.
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In some embodiments, the flange portion may be arranged within the mounting opening at a distance from a terminal end of the body part.
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In some embodiments, the metal member may be a metal sleeve and the mounting hole may be a through hole.
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In some embodiments, the mounting hole may be a thread hole for engaging the screw fastener.
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In some embodiments, the metal members may be integrally formed with the body part and the flange portion by insert molding.
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In some embodiments, the body part may be a tubular form being curved in an L-shape, or may be in a straight arm form.
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In a second aspect of the present disclosure, there is provided an arm body for a robotic arm. The arm body comprises a body part made of plastic material and comprising a mounting opening; and a mounting interface provided at the mounting opening and comprising a connecting portion extending lengthwise along the body part, the connecting portion comprising a plurality of holes circumferentially distributed around the mounting opening, wherein the connecting portion comprises a metal connecting portion, and the hole is configured to receive a screw fastener; or the connecting portion comprises a plastic material connecting portion and a plurality of metal members is arranged within a respective hole of the plurality of holes, the metal member comprising a mounting hole configured to receive a screw fastener. With this arrangement, the connection strength at the mounting interface can be improved.
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In some embodiments, an inner or outer circumferential surface of the connecting portion may form an attaching surface configured to be connected to a second component of a robot.
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In some embodiments, the metal member may extend in a direction perpendicular to a direction in which the mounting opening opens.
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In some embodiments, the connecting portion may extend from a terminal end of the body part around the mounting opening.
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In some embodiments, the metal member may be a metal sleeve and the mounting hole may be a through hole.
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In some embodiments, the mounting hole may be a thread hole for engaging the screw fastener.
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In some embodiments, the metal members may be integrally formed with the first body part and the connecting portion by insert molding.
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In some embodiments, the body part may be a tubular form being curved in an L-shape, may be in a straight arm form.
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In a third aspect of the present disclosure, there is provided a robotic arm. The robotic arm comprises an arm body according to any of preceding claims; and an actuator at least partially arranged within the body part and comprising a fixed mounting portion and a movable mounting portion, wherein the fixed mounting portion of the actuator is configured to abut against of the mounting interface of the arm body and fixed to the mounting interface of the first arm body via the screw fastener.
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In some embodiments, the fixed mounting portion may comprise a through hole for passage of the screw fastener, or a thread hole for engaging the screw fastener
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In some embodiments, the robotic arm may further comprise a second arm body, wherein the second arm body is fixed to the movable mounting portion of the actuator, or to the mounting interface of the first arm body.
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In some embodiments, the second arm body may comprise a second body part made of the plastic material and comprising a second mounting opening; and a second mounting interface provided at the second mounting opening and comprising a second connecting portion, the second connecting portion comprising a plurality of second holes around the second mounting opening and an attaching surface configured to engage a corresponding attaching surface of the movable mounting portion or of the mounting interface of the first arm body; wherein the second connecting portion is made of metal, the second hole being configured to receive a screw fastener, or the second connecting portion is made of the plastic
material and a plurality of second metal members is arranged within a respective hole of the plurality of holes and is configured to receive a screw fastener.
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In a fourth aspect of the present disclosure, there is provided an industrial robot comprising a base, and a robotic arm comprising an arm body according to the first and second aspects of the present disclosure.
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It would be appreciated that this summary is not intended to identify key features or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become evident through the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
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Through the following detailed descriptions with reference to the accompanying drawings, the above and other objectives, features and advantages of the example embodiments disclosed herein will become more comprehensible. In the drawings, several example embodiments disclosed herein will be illustrated in an example and in a non-limiting manner, wherein:
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Fig. 1 is an overall view of an industrial robot according to an example embodiment of the present disclosure;
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Fig. 2 is a perspective view of a robotic arm including one arm body according to a first example embodiment of the present disclosure;
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Fig. 3 is a sectional view of Fig. 2;
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Fig. 4 is a sectional view of the robotic arm of Fig. 2, with an actuator being provided within the arm body and an outer axial end surface of a mounting interface with respect to an inner chamber being used as a attaching surface;
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Fig. 5 is a sectional view of a robotic arm including one arm body according to a second example embodiment, with an actuator being provided within the arm body and an inner axial end surface of a mounting interface with respect to an inner chamber being used as a attaching surface;
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Fig. 6 is a perspective view of a robotic arm including one arm body according to a third example embodiment of the present disclosure;
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Fig. 7 is a sectional view of a robotic arm including two arm bodies according to one
example embodiment of the present disclosure;
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Fig. 8 is a perspective view of a robotic arm including one arm body according to a fourth example embodiment of the present disclosure;
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Fig. 9 is a sectional view of a robotic arm including three arm bodies according to one example embodiment of the present disclosure;
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Fig. 10 is an enlarged sectional view of a circled portion of Fig. 9;
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Fig. 11 is a perspective view of a robotic arm including one arm body according to a fifth example embodiment of the present disclosure.
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Throughout the drawings, the same or similar reference symbols are used to indicate the same or similar elements.
DETAILED DESCRIPTION OF EMBODIMENTS
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Principles of the present disclosure will now be described with reference to several example embodiments shown in the drawings. Though example embodiments of the present disclosure are illustrated in the drawings, it is to be understood that the embodiments are described only to facilitate those skilled in the art in better understanding and thereby achieving the present disclosure, rather than to limit the scope of the disclosure in any manner.
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The term “comprises” or “includes” and its variants are to be read as open terms that mean “includes, but is not limited to. ” The term “or” is to be read as “and/or” unless the context clearly indicates otherwise. The term “based on” is to be read as “based at least in part on.” The term “being operable to” is to mean a function, an action, a motion or a state that can be achieved by an operation induced by a user or an external mechanism. The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The terms “first, ” “second, ” and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below. A definition of a term is consistent throughout the description unless the context clearly indicates otherwise.
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Fig. 1 is an overall view of an industrial robot 100 according to one example embodiment of the present disclosure. As shown in Fig. 1, the industrial robot 100 comprises a base 30, a plurality of joints (only its casing being shown and labeled as 10a, 10b, 10c, 10d) , and a plurality of connecting arms 20 (labeled as 20a, 20b in the shown example) connecting
two adjacent joints. Each joint may include a casing. One or more actuators 50 (labeled as 50a, 50b, 50c, 50d in the shown example) are provided within the casing. The actuator, among the others, may include a motor, a sensor, a reduction gear, and the like which is generally well known in the art. A controller may be provided in the base 30. The actuators within the casing can be controlled by the controller so as to control a posture of the robotic arm and/or a movement path of an end effector provided at the distal end of the robotic arm. In the shown example, each casing 10a, 10b, 10c, 10d may include work openings (show as an inclination line in Fig. 1) and the work openings may be covered by a cover. Through the work openings, an engineer can access an inner side of the casing so as to fix the actuators in position within the casing or to perform maintenance work. Instead of provision of work openings, in some example embodiments (not shown) , the casing and the connecting arms 20 may be substantially closed without provision of the work openings.
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The casing of the joint and the connecting arms 20 are load bearing members and are designed with sufficient strength. As mentioned above, due to the fact that the plastic member can be manufactured by injection molding, which means lower manufacturing costs and many complex steps that are needed in processing conventional metal members can be omitted, there thus is technical trend that using plastic material to manufacture the arm body and the connecting arms. However, when two components made of plastic material are fixed together, there is a high risk that connection between the two plastic components becomes loose or connection strength between the components becomes insufficient when the robot operates over time. That is because plastic material has a creep risk when the plastic components of the robot operate under stress over a long time. According to the present disclosure, a novel connection means is proposed to ensure strong connection strength at a connection interface of two plastic components.
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Figs. 2-4 show a robotic arm including one arm body 10 according to a first example embodiment of the present disclosure. As shown in Figs. 2-4, the arm body 10 includes a body part 11 made of plastic material. The body part 11 may be curved in an L shape. The body part 11 defines an inner chamber. Two mounting openings 13 may be provided at two opposite ends of the body part 11. Components of an actuator may be arranged within the inner chamber. In the shown example, a work opening 15 may be provided in the body part 11. Through the work opening 15, the inner chamber of the body part 11 can be accessed by an engineer. The work opening 15 may be closed by a cover. In the shown example, the body part 11 is wholly in a form of tube. In some other embodiments, the body part 11 may only
partial be formed as a tube, for example, at the positions to be connected and other part of the body 11 may be formed into other shapes. It is to be understood that there is merely illustrative and the body part 11 may be formed as any other proper shapes.
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The body part 11 may include one or two mounting interface 12 provided at the respective mounting opening 13. The mounting interface 12 provides an interface for connecting the arm body to other components constituting the robot, such as the actuator or other arm bodies. In the shown example, since the two mounting interfaces 12 are substantially the same, only one of the two mounting interfaces 12 is detailed in the following description. It is to be understood that the two mounting interfaces 12 may be different from teach other.
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The mounting interface 12 may include a flange portion 122. The flange portion 122 extends radially inward from an inner wall surface of the body part 11. The mounting opening 13 is partially blocked by the flange portion 122. The flange portion 122 is made of the plastic material. Accordingly, the flange portion 122 and the body part 11 may be integrally formed by injection molding. The inner or outer axial end surface of the flange portion 122 may be used as an attaching surface. In the shown example, as shown in Figs. 2-4, the outer axial end surface 128 with respect the inner chamber of the body part 11 is used as the attaching surface for connecting another component. The flange portion 122 may include a plurality of holes 124 circumferentially distributed around the mounting opening 13. The holes 124 extends axially in parallel with a direction that the mounting opening 13. The holes 124 may be evenly distributed around the mounting opening 13. The number of holes 124 may be proper numeric value and the patterns of the holes may by any other proper forms as long as the connection strength can be achieved. A plurality of metal members 126 may be arranged within a respective hole of the plurality of holes 124. The metal member 126 may include a mounting hole 127 configured to receive a screw fastener 40. The metal member 126 may be of various shapes. In the shown example, the metal member 126 is of a cylindrical shape. It is to be understood that the metal member 126 may be of any other proper shapes. The metal members 126 may be integrally formed with the flange portion 122 by insert molding. Due to use of the metal members 126, the screw fastener 40 is configured to contact the metal member 126 rather than the plastic material. Thus, the creep risk of the plastic material can be avoided during operation of the robot. Even if the robot operates over a long time, there is no risk that the screw fastener 40 becomes loose. Moreover, the hole 124 extends axially. This is advantageous for injection molding the body part 11 since it is easy to realize a draft angle for
injecting molding.
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As shown in Figs. 3 and 4, the mounting hole 127 in the metal member 126 is a thread hole which is configured to engage a screw fastener 40. The actuator 50 may include a mounting portion 52. The mounting portion 52 of the actuator 50 is configured to abut against the attaching surface 128. In the shown example embodiment, the mounting portion 52 may be a fixed part of the actuator. The fixed part, among the others, includes a stator of a motor. The mounting portion 52 may include a plurality of mounting holes 57. The mounting hole 57 may be a through hole. When the actuator 50 is placed in position within the body part 11, the mounting holes 57 align with the mounting hole 127. The screw fastener 40 axially passes through the mounting hole 57 in the mounting portion 52 and further goes into the mounting hole 127. The screw fastener 40 engages the inner thread provided in the mounting hole 127. In this way, the actuator 50 is fixed to the body part 11.
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In the shown example, the flange portion 122 may be arranged within the mounting opening 13 and is at a distance from a terminal end of the body part. The flange portion 122 may be used as a location portion that can locate the actuator 50. It is advantageous when assembling the actuator. In some other embodiments, the flange portion 122 may be arranged at other proper positions, for example at the mounting opening 13.
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In the shown example embodiment, one actuator 50 is provided within the body part 11 at one end. The other end of the body part 11 is used for connecting other components constituting the robot, for example, a connecting arm 20. Alternatively or in addition, in other example embodiment (not shown) , two actuators 50 may be provided at the respective end of the body part 11.
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In some example embodiments, the flange portion 122 may be configured to be fixed to a fixed part of the actuator 50. In other example embodiment, the flange portion 122 may be configured to be fixed to a movable part of the actuator 50. The movable part, among the others, includes a rotor of the motor. The rotor is configured to rotate around an axial direction. A reduction gear may be connected to the rotor. Components to be driven, for example, an adjacent connecting arm, may be further connected to the reduction gear. Thus, the adjacent connecting arm may be driven to rotate around the axial direction.
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Fig. 5 shows a sectional view of another robotic arm including one arm body. The embodiment of Fig. 5 is analogous to that shown in Figs. 2-4. The following description of the Fig. 5 mainly focuses on their differences. As shown in Fig. 5, the body part 11 may include a
flange portion 122 which is used as a mounting interface. The flange portion 122 extends radially inward from an inner wall surface of the body part to partially block the mounting opening. The flange portion 122 is made of the plastic material. Thus, the flange portion 122 can be integrally formed with the body part 11 by injection molding. A plurality of metal members 126 are provided in the flange portion 122. Different from the embodiment shown in Figs. 2-4, in the arm body 10 of Fig. 5, an inner axial end surface 128 with respect to the inner chamber of the body part is used as an attaching surface, and the metal member 126 is a metal sleeve and is embedded in the flange portion 122. The metal member 126 is provided a mounting hole 127 for passage of the screw fastener 40. In some embodiments, the metal members 126 may be integrally formed with the body part 11 and the flange portion 122 by insert molding.
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As shown in Fig. 5, the mounting portion 52 of the actuator 50 is configured to abut against the attaching surface 128 of the flange portion 122. The mounting portion 52 of the actuator 50 may be a fixed part of a movable part of the actuator. The mounting portion 52 may include a plurality of mounting holes 57. The mounting holes 57 may be thread holes. When the actuator 50 is placed in position within the body part 11, the mounting holes 57 of the mounting portion 52 align with the mounting holes 127 in the flange portion 122. The screw fastener 40 axially passes through the mounting hole 127 in the flange portion 122 and further goes into the mounting holes 57 in the mounting portion 52. The screw fastener 40 engages the inner thread provided in mounting holes 57 in the mounting portion 52. In this way, the actuator 50 is fixed to the body part 11.
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Fig. 6 is a perspective view of a robotic arm including one arm body 20 according to a second example embodiment of the present disclosure. The arm body 20 may be corresponding to the connecting arm shown in Fig. 1. In Fig. 6, the arm body 20 is formed as a long straight arm form and is provided with an opening 25 at one lengthwise side. The opening 25 may be covered by a cover (not shown) so as to enclosure the opening 25. The arm body 20 may have two opposite longitudinal ends. The arm body 20 is made of the plastic material and may include a body part 21 at its two opposite longitudinal end portions. The body part 21 defines a mounting opening 23 and a mounting interface 22 is provided at the mounting opening 23. In the shown example, the two mounting interfaces 22 are substantially the same. It is to be understood that the two mounting interfaces 22 may be different from teach other.
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The mounting interfaces 22 may include a flange portion 222. The flange portion 222
extends radially inward from an inner wall surface of the body part. The mounting opening 23 is partially blocked by the flange portion 222. The flange portion 222 is made of the plastic material. Accordingly, the flange portion 222 and the body part 21 may be integrally formed by injection molding. The inner or outer end surface of the flange portion 122 may be used as an attaching surface.
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The flange portion 222 may include a plurality of holes 224 circumferentially distributed around the mounting opening 23. The holes 224 may be evenly distributed around the mounting opening 13. A plurality of metal members 226 (shown in Fig. 7) may be arranged within a respective hole of the plurality of holes 224. The metal member 226 may include a mounting hole configured to receive a screw fastener 40. The metal member 226 may be of various shapes. In the shown example, the metal member 226 is of a cylindrical shape. In one example, the metal members 226 may be integrally formed with the flange portion 222 by insert molding. Due to use of the metal members 226, the screw fastener 40 is configured to contact the metal member 226 rather than the plastic material. Thus, the creep risk of the plastic material can be avoided.
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The arm body 20 may be connected other components constituting the robot, such as another arm body or a movable prat of another arm body. In some embodiments, an actuator may be provided within the arm body 20. The actuator (for example, a fixed part of the actuator) may be fixed to the arm body 20 at the flange portion 222.
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Fig. 7 is a sectional view of a robotic arm including two arm bodies 10, 20 according to one example embodiment of the present disclosure. The arm body 10 shown in Fig. 7 may be substantially the same as that shown in Figs. 2-4. The arm body 20 shown in Fig. 7 may be substantially the same as that shown in Fig. 6. Fig. 7 shows how the first arm body 10 is connected to the second arm body 20.
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As shown in Fig. 7, the actuator 50 is provided within the body part 11. The actuator 50 may include a first mounting portion 52 (for example, a fixed part of the actuator) and a second mounting portion 54 (for example, a movable part of the actuator) . The first mounting portion 52 may include a mounting hole 57 (for example, a through hole) . The first mounting portion 52 may engage an outer radial axial end surface (i.e., attaching surface) of the flange portion 122. The flange portion 122 may include a mounting hole 127 (for example a thread hole provided in a metal member, also referring to Figs. 3 and 4) . A screw fastener 40 axially passes through the mounting hole 57 in the first mounting portion 52 and engages the
mounting hole 124. In this way, the actuator 50 is fixed to the body part 11 via the screw fastener 40
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The second mounting portion 54 may include a mounting hole (not shown) which extend axially. The mounting hole provided in the second mounting portion 54 may be a thread hole. The second mounting portion 54 may engage an outer axial end surface 228 (i.e., attaching surface) of the flange portion 222. The flange portion 222 may include a mounting hole 224 (for example a through hole provided in a metal member) . A screw fastener 40 axially passes through the mounting hole 224 in the flange portion 222 and engages the mounting hole in the second mounting portion 54. In this way, the arm body 20 is fixed to the second mounting portion 54 of the actuator 50 via the screw fastener 40. With this arrangement, due to the arrangement of the metal member 226 with in the flange portion 222, the creep risk of the plastic material can be avoided.
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As shown in Fig. 7, the flange portion 222 may be arranged within the mounting opening 23 and is at a distance from a terminal end of the body part. An extension 28 of the terminal end of the body part may be used as a location means during assembly. The extension 28 may partially engage a corresponding extension 18 of the body part 11. When the arm body 10 and arm body 20 are placed in position, the arm body 10 can align with the arm body 20 easily.
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Fig. 8 shows a perspective view of a robotic arm including one arm body 10 according to a fourth example embodiment of the present disclosure. As shown in Fig. 8, the arm body 10 includes a body part 11 made of plastic material. The body part 11 may be re curved in an L shape and may include two opposite ends. The body part 11 defines an inner chamber. Two mounting openings 13 may be provided at each end of the body part 11. Components of an actuator may be arranged within the inner chamber. In the shown example, the body part 11 is substantially closed beside the mounting openings 13. The body part 11 is curved in an L shape. It is to be understood that there is merely illustrative and the body part 11 may be formed as any other proper shapes.
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The body part 11 may include one or two mounting interface 12 provided at the respective mounting opening 13. The body part 11 is attached to other components, constituting the robot such as the actuator or the connecting arm 20 via the mounting interface 12. In the shown example, the two mounting interfaces 12 are substantially the same. It is to be understood that the two mounting interfaces 12 may be different from teach other.
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The mounting interface 12 may include a connecting portion 122. The connecting portion 122 extends lengthwise along a wall surface of the body part. The mounting opening 13 may not block the mounting opening 13. The connecting portion 122 may be made of the plastic material. The connecting portion 122 and the body part 11 may be integrally formed, for example, by injection molding.
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The connecting portion 122 may comprise a plurality of holes 124 circumferentially distributed around the first mounting opening 13. In the shown example, the whole outer circumferential surface of the connecting portion 122 is evenly provided with holes 124. This is merely illustrative. The holes may be provided at certain circumferential zone. This may be advantageous for a draft angle during manufacturing. The inner or outer circumferential surface of the connecting portion 122 may be used as an attaching surface 128. This is advantageous in many applications. Since the circumferential surface of the connecting portion 122 is used as the attaching surface 128, the engineer can realize assembly of the arm bodies without need to access the inner chamber.
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A plurality of metal members 126 (referring to Figs. 9 and 10) may be arranged within a respective hole of the plurality of holes 124. The metal member 126 may comprise a mounting hole 127 configured to receive a screw fastener 40. The metal member 126 may be of various shapes. In the shown example, the metal member 126 is of a cylindrical shape. It is to be understood that the metal member 126 may be of any other proper shapes. In one example, the metal members 126 may be integrally formed with the connecting portion 122 by insert molding. Due to use of the metal members 126, the screw fastener 40 is configured to contact the metal member 126 rather than the plastic material. Thus, the creep risk of the plastic material can be avoided. Even if the robot operates over a long time, there is no risk that the screw fastener 40 becomes loose.
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Fig. 9 is a sectional view of a robotic arm including three arm bodies according to one example embodiment of the present disclosure. Fig. 10 is an enlarged sectional view of a circled portion of Fig. 9. As shown in Fig. 9, three arm bodies 10a, 10b, 20 are connected as a whole to form the robotic arm. The arm body 10a is substantially the same as the arm body 10b and is corresponding to the arm body 10 shown in Fig. 8. The arm body 20 is analogous to the arm body 10a, 10b but is of different shape. In Fig. 9, the arm bodies 10a, 10b are curved in an L shape while the arm body 20 is of a straight cylindrical shape.
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Within each body part, an actuator 50 may be provided. Fig. 9 shows how an actuator
50 is fixed to a body part 11a, 11b of the arm body 10a, 10b respectively. As shown in Fig. 9, the actuator 50 is provided within a body part 11a of the arm body 10a. The actuator 50 may include a first mounting portion 52 (for example, a fixed part of the actuator) and a second mounting portion 54 (for example, a movable part of the actuator) . As shown in Figs. 9 and 10, the first mounting portion 52 may include a mounting hole 57 which extends radially. The mounting hole 57 may be a thread hole. The mounting portion 52 may engage an inner circumferential surface 128 (i.e., attaching surface) of the connecting portion 122a. The connecting portion 122a may include a mounting hole 127. The mounting hole 127 may be a through hole provided in the metal member 126. A screw fastener 40 radially passes through the mounting hole 127 of the connecting portion 122a and engages the mounting hole 57 in the first mounting portion 52. In this way, the actuator 50 is fixed to the arm body 10a via the screw fastener 40. With the same manners, the actuator 50 is fixed to the arm body 10b and its description is omitted.
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Fig. 9 also shows how the arm body 10b is fixed to the arm body 10a. As shown in Fig. 9, the second mounting portion 54 may include a mounting hole which extends radially and may be a thread hole. The second mounting portion 54 may engage an inner circumferential surface (i.e., attaching surface) of the connecting portion of the arm body 10b. The connecting portion of the arm body 10b may include a mounting hole. The mounting hole may be a through hole provided in the metal member. A screw fastener 40 radially passes through the mounting hole of the connecting portion 122b of the arm body 10b and engages the mounting hole in the second mounting portion 54. In this way, the arm body 10b is fixed to the second mounting portion 54 of the actuator 50 via the screw fastener 40.
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As shown in Fig. 9, the arm body 20 may be corresponding to the connecting arm 20 shown in Fig. 1. In Fig. 9, the arm body 20 is formed as a long arm form. The arm body 20 may have two opposite longitudinal ends (only one end is shown in Fig. 9) . The arm body 20 is made of the plastic material and may include a body part 21. The body part 21 defines a mounting opening 23 and a mounting interface 22 is provided at the mounting opening 23. The mounting interfaces 22 may include a connecting portion 222. The connecting portion 222 extends lengthwise along a wall surface of the body part 21. The connecting portion 222 may be made of the plastic material. The connecting portion 222 and the body part 21 may be integrally formed, for example, by injection molding.
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The connecting portion 222 may comprise a plurality of holes 224 circumferentially distributed around the mounting opening 23. The inner or outer circumferential surface of the
connecting portion 122 may be used as an attaching surface. A plurality of metal members may be arranged within a respective hole of the plurality of holes. The metal member may comprise a mounting hole configured to receive a screw fastener 40.
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As shown in Fig. 9, a connecting portion 122c extends lengthwise along a wall surface of the body part 10a at an opposite end to the connecting portion 122a. The connecting portion 122c may be made of the plastic material. The connecting portion 122c and the body part 10a may be integrally formed, for example, by injection molding. The connecting portion 122c may include a mounting hole. The mounting hole may be a through hole provided in the metal member. A screw fastener 40 radially passes through the mounting hole of the connecting portion 122c and engages the mounting hole in the connecting portion 222. In this way, the arm body 20 is fixed to the arm body 10a via the screw fastener 40.
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In the shown embodiment, the connecting portions 122a, 122b, 200 are made of plastic material and metal inserts for screw connection are embedded in the plastic material. In some other embodiments, the connecting portions 122a, 122b, 200 may be made of metallic material and the meal inserts can be omitted.
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Fig. 11 shows is a perspective view of a robotic arm including one arm body 10 according to a fifth example embodiment of the present disclosure. As shown in Fig. 11, the arm body 10 includes a body part 11 made of plastic material. At a first end, a first mounting interface 12a is provided at a first axial opening 13a and may include a connecting portion 122a. The connecting portion 122a extends lengthwise along a wall surface of the body part. The connecting portion 122a may be made of metal and a plurality of holes 124a may be provided therein to receive a screw fastener. Alternatively, the connecting portion 122a may be made of the plastic material and a plurality of second metal members may be embedded in the connecting portion 122a for screw connection.
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At a second end, a second mounting interface 12b is provided at a second axial opening 13b and may include a flange portion 122b. The flange portion 122b extends radially inward from an inner wall surface of the body part. The flange portion 122b may be made of metal and a plurality of holes 124b may be provided in the flange portion 122b to receive a screw fastener. Alternatively, the flange portion 122b may be made of the plastic material and a plurality of second metal members may be embedded in the connecting portion 122a for screw connection.
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Through the teachings provided herein in the above description and relevant
drawings, many modifications and other embodiments of the disclosure given herein will be appreciated by those skilled in the art to which the disclosure pertains. Therefore, it is understood that the embodiments of the disclosure are not limited to the specific embodiments of the disclosure, and the modifications and other embodiments are intended to fall within the scope of the disclosure. In addition, while exemplary embodiments have been described in the above description and relevant drawings in the context of some illustrative combinations of components and/or functions, it should be realized that different combinations of components and/or functions can be provided in alternative embodiments without departing from the scope of the disclosure. In this regard, for example, it is anticipated that other combinations of components and/or functions that are different from the above definitely described will also fall within the scope of the disclosure. While specific terms are used herein, they are only used in a general and descriptive sense rather than limiting.