Methods for holding robotic arms and wire harnesses with connectors

Abstract

The aim is to hold the connector in a specific position and orientation, and to insert the connector into a connector port located in a confined space. The robotic arm 1 includes: a hand base 11; a push-press mechanism 20, freely movable and supported on the hand base, for pressing the connector from above; a front wire clamping mechanism 30, freely lifting and moving back and forth and supported on the hand base, for clamping a wire harness; a rear wire clamping mechanism 50, freely lifting and supporting on the hand base, for clamping a wire harness; and a pair of abutments 41, 42, with a pair of fingers 31, 32 of the front wire clamping mechanism pressed against the connector from the rear.

Description

Technical Field

[0001] This invention relates to a robotic arm and a method for holding a harness with a connector. Background Technology

[0002] The automation of various assembly processes is being carried out using robots. One of the more challenging processes is inserting connectors into connector ports. In order for a robotic arm to hold the wire harness and connector and insert it correctly into the connector port, the robotic arm needs to hold the connector in a specific position and in a specific orientation.

[0003] To supply connectors and wiring harnesses to a specific position relative to a robotic arm in a defined orientation, complex grippers are required. Alternatively, a camera can be used to capture images of the connectors and wiring harnesses being supplied in a relatively free state. Based on these camera images, the approach direction, orientation, and posture of the hand relative to the connector can be controlled in a manner that holds the connector in a defined orientation and position. However, challenges also exist regarding the posture of the robotic arm and the structure of the hand.

[0004] Patent Document 1 discloses a robotic arm that directly grips a coupler (connector) using a pair of clamping discs. However, in such a structure that directly grips the connector, the hand is wider than the connector when holding it. Therefore, when the connector port is located in a narrow space, the hand may sometimes interfere with the surrounding environment and be unable to insert the connector into the connector port.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 06-188061 Summary of the Invention

[0008] Problems to be solved by the invention

[0009] The desired feature is a hand that can hold the connector in a specific position and orientation and insert the connector into a connector port located in a confined space.

[0010] means for solving problems

[0011] One aspect of the disclosed robotic arm for holding wire harnesses includes: a hand base; a push-press mechanism supported on the hand base and movable back and forth for pressing a connector from above; a front wire clamping mechanism supported on the hand base and movable back and forth for clamping a wire harness; a rear wire clamping mechanism supported on the hand base and movable back and forth for clamping a wire harness; and a pair of abutments, a pair of fingers of the front wire clamping mechanism being pressed against the connector from the rear. The push-press mechanism presses the connector onto a mounting platform, making the connector parallel to the platform. The rear wire clamping mechanism clamps the wire harness. With the front wire clamping mechanism moving forward to press the abutments against the connector, the front wire clamping mechanism clamps and holds the wire harness.

[0012] The effects of the invention

[0013] It can hold the connector in a specific position and direction, and can insert the connector into a connector port located in a narrow space. Attached Figure Description

[0014] Figure 1 This is a side view showing a robot with the robotic arm of this embodiment installed.

[0015] Figure 2 It is shown Figure 1 A 3D diagram of an example robotic arm.

[0016] Figure 3 It was omitted. Figure 2 A side view of a portion of the robotic arm.

[0017] Figure 4 It was omitted. Figure 2 A top view of a portion of the robotic arm.

[0018] Figure 5 It is shown Figure 2 The diagram shows the first stage of the gripping action of the robotic arm.

[0019] Figure 6 It is shown Figure 2 The diagram shows the second stage of the robotic arm's grasping action.

[0020] Figure 7 It is shown Figure 2 The diagram shows the third stage of the gripping action of the robotic arm.

[0021] Figure 8 It is shown Figure 2 The diagram shows the fourth stage of the gripping action of the robotic arm.

[0022] Figure 9 It is shown Figure 2 The diagram shows the fifth stage of the gripping action of the robotic arm.

[0023] Figure 10 This is a diagram showing another example of the pressing part of the robotic arm in this embodiment.

[0024] Figure 11 This is a diagram illustrating another example of the first finger of the robotic hand in this embodiment.

[0025] Figure 12 This is a side view showing another example of the mounting position of the camera of the robotic arm in this embodiment.

[0026] Explanation of reference numerals in the attached figures

[0027] 1: Robotic arm; 11: Hand base; 13: Clamping plate base; 15: Base lifting mechanism; 20: Push-press mechanism; 21: Pad; 23: Push-press pin; 25: Pin lifting mechanism; 27: First forward and backward movement mechanism; 30: Front wire clamping plate mechanism; 31, 32: First finger; 35: First opening and closing mechanism; 37: Second forward and backward movement mechanism; 41, 42: Pressing part; 50: Rear wire clamping plate mechanism; 51, 52: Second finger; 55: Second opening and closing mechanism; 61: Connector detection camera; 63: Camera bracket; 71: Overall detection camera; 73: Camera bracket. Detailed Implementation

[0028] The robotic arm of this embodiment will now be described with reference to the accompanying drawings. The robotic arm of this embodiment is used to grasp a wire harness with a connector attached to its front end. Typically, it is mounted on the arm end of various types of robotic arm mechanisms, such as vertical multi-joint type, horizontal multi-joint type, and polar coordinate type. In the following description, structural elements having substantially the same function and structure will be given the same reference numerals and will be described repeatedly only where necessary.

[0029] like Figure 1 As shown, the robotic arm 1 is mounted on the wrist at the front end of the robotic arm mechanism 3 for use. Both the robotic arm mechanism 3 and the robotic arm 1 are controlled by a control device 5. The control device 5 includes a storage device such as an HDD (hard disk drive) storing a gripping program for controlling the gripping actions of the robotic arm 1, and a processing unit such as a CPU (central processing unit) that executes the program stored in the storage device. By executing the gripping program through the processing unit, the robotic arm 1 and the robotic arm mechanism 3 move together according to the gripping sequence specified by the hand control program, enabling them to grip a wire harness with connectors.

[0030] (robotic arm)

[0031] The following is for reference Figures 2 to 4The structure of the wire harness holding robot 1 will be described. Figure 2 This is a 3D view of the front side of robotic arm 1. Figure 3 This is a side view of robotic arm 1. Figure 4 This is a top view of robotic arm 1. Figure 3 In order to clearly define the main structural elements of the robotic arm 1, the connector inspection camera 61 and the overall inspection camera 71 have been omitted. Figure 4 In order to clarify the positional relationship between the pad 21 of the pressing mechanism 20, the pair of first fingers 31 and 32 on the front side, and the pair of second fingers 51 and 52 on the rear side, structural elements other than them are omitted.

[0032] like Figure 2 , Figure 3 As shown, the robotic arm 1 has a rectangular plate-shaped hand base 11. In the following description, the long side direction of the hand base 11 is appropriately used as the front-back direction, the short side direction of the hand base 11 is used as the left-right direction, and the thickness direction of the hand base 11 is used as the up-down direction.

[0033] A connector detection camera 61 for photographing the connector and an overall inspection camera 71 for overhead photographing of the wiring harness with connectors are provided on the hand base 11. The connector detection camera 61 is mounted in front of the hand base 11 with the shooting direction facing downward via a camera bracket 63. The overall inspection camera 71 is mounted on the side of the hand base 11 with the shooting direction facing downward via a camera bracket 73.

[0034] The hand base 11 supports a push-press mechanism 20 for pressing the connector placed on the mounting platform 7 from above, and two wire clamping mechanisms 50 and 30 for holding the wire harness.

[0035] The push-button mechanism 20 has a cylindrical push pin 23 and a pin lifting mechanism 25 that moves the push pin 23 up and down in the vertical direction. Typically, a resilient resin pad 21 for contacting the connector is installed at the front end of the push pin 23. The push-button mechanism 20 is connected to the front portion of the hand base 11 via a first forward and backward movement mechanism 27. The push-button mechanism 20 may also be fixed to the hand base 11 without the first forward and backward movement mechanism 27.

[0036] A rectangular plate-shaped clamp base 13 is connected to the hand base 11 via a base lifting mechanism 15. The clamp base 13 is positioned below the hand base 11 and parallel to it. Two wire clamping mechanisms 30 and 50 are supported on the clamp base 13. The two wire clamping mechanisms 30 and 50 are respectively positioned in a front-to-back separated position. The two wire clamping mechanisms 30 and 50 can also be connected to separate lifting mechanisms.

[0037] The front wire clamp mechanism 30 is connected to the clamp base 13 via a second forward / backward movement mechanism 37. The front wire clamp mechanism 30 has a pair of first fingers 31, 32 and a first opening / closing mechanism 35 that opens and closes the pair of first fingers 31, 32 in the left-right direction. Typically, the pair of first fingers 31, 32 each has an L-shaped outer shape and is mounted on the first opening / closing mechanism 35 in a manner that is parallel to each other in the vertical and forward / backward directions and with the front end pointing forward. A pair of abutting portions 41, 42 are integrally formed on each of the pair of first fingers 31, 32, which press against the connector from the rear of the connector. Typically, the pair of abutting portions 41, 42 each has an outwardly expanding L-shaped planar shape and is connected to the front end of the pair of first fingers 31, 32 in a manner that forms a U-shaped or U-shaped planar shape as a whole.

[0038] The rear wire clamp mechanism 50 has a pair of second fingers 51, 52 and a second opening and closing mechanism 55 that opens and closes the pair of second fingers 51, 52 in the left and right direction. Typically, the pair of second fingers 51, 52 each have a rod-shaped shape and are mounted parallel to each other in the up and down direction on the second opening and closing mechanism 55.

[0039] like Figure 4 As shown, the push-press mechanism 20, the front wire clamping mechanism 30, and the rear wire clamping mechanism 50 are positioned such that the center position of the pad surface of the pad 21 that contacts the connector, the opening and closing center position of the pair of first fingers 31, 32 of the front wire clamping mechanism 30, and the opening and closing center position of the pair of second fingers 51, 52 of the rear wire clamping mechanism 50 are arranged on the reference line LF of the robot arm 1 extending in the front-rear direction.

[0040] (Sequence of control)

[0041] The following is for reference Figures 5 to 9 The gripping sequence of the robotic arm 1 using this embodiment for gripping the wire harness A with connector will be explained. First, based on the overall image captured by the overall inspection camera 71, the connector B and the wire harness C are inspected, and the robotic arm 1 is moved by the robotic arm mechanism 3 with the opening and closing centers of the two clamping mechanisms 30 and 50 positioned above the wire harness C.

[0042] like Figure 5As shown, the two wire clamping mechanisms 30 and 50 are lowered by the base lifting mechanism 15. This allows the front portion of the wire harness C to be surrounded by a pair of first fingers 31 and 32 of the front wire clamping mechanism 30, and the rear portion of the wire harness C to be surrounded by a pair of second fingers 51 and 52 of the rear wire clamping mechanism 50. At this time, connector B is located on the reference line LF. Next, connector B is detected based on the connector image captured by the connector detection camera 61, and the forward and backward position of the push-press mechanism 20 is adjusted by the first forward and backward movement mechanism 27.

[0043] like Figure 6 As shown, after the position of the push-button mechanism 20 is adjusted, the push-button pin 23 is lowered by the pin lifting mechanism 25. As a result, connector B is pressed against the mounting platform 7 by the pad 21 (push-button pin 23). The lower surface of connector B, pressed against the mounting platform 7, is parallel to the mounting surface of the mounting platform 7.

[0044] like Figure 7 As shown, the second opening and closing mechanism 55 of the rear wire clamping mechanism 50 is closed, and the wire harness C is clamped and held by a pair of second fingers 51, 52.

[0045] like Figure 8 As shown, with the wire harness C held by a pair of second fingers 51 and 52, the front wire clamping mechanism 30 is moved forward using the second forward and backward moving mechanism 37, and a pair of pressing parts 41 and 42 are pressed against the rear end face of the connector B. This allows the position and orientation of the connector B relative to the clamping position of the wire harness C by the pair of second fingers 51 and 52 to be fixed.

[0046] like Figure 9 As shown, the first opening and closing mechanism 35 of the front wire clamping mechanism 30 is closed, and the wire harness C is clamped by a pair of first fingers 31 and 32.

[0047] Using the gripping sequence described above, robot arm 1 can grip the wire harness A with connectors using two wire clamping mechanisms 30 and 50. Sometimes, the orientation of connector B of the wire harness A with connectors gripped by robot arm 1 deviates from the prescribed direction. Therefore, it is desirable to have connector detection camera 61 capture an image of connector B of the wire harness A with connectors gripped by robot arm 1, and detect the amount of deviation of connector B's orientation from the prescribed direction based on the captured image. Based on the detected amount of deviation of connector B's orientation, the orientation of robot arm 1 is corrected when inserting the wire harness A with connectors gripped by robot arm 1 into the connector port, thereby enabling high-precision insertion of connector B of the wire harness A with connectors into the connector port.

[0048] (Effect)

[0049] The robotic arm 1 of this embodiment described above can hold a wire harness with a connector by clamping the wire harness with a pair of first fingers 31, 32 of the front wire clamping mechanism 30 and a pair of second fingers 51, 52 of the rear wire clamping mechanism 50, while pressing a pair of abutting portions 41, 42 connected to the front pair of first fingers 31, 32 against the rear end face of the connector. The connector is almost entirely exposed except for its rear end face, and can be held in a state where it protrudes towards the front ends of the first fingers 31, 32. Since the sides of the connector are not clamped, the first fingers 31, 32 do not protrude beyond the width of the connector, or even if they do, the protrusion is suppressed to a slight degree. According to the robotic arm 1 of this embodiment, a connector can be inserted into a connector port located in a narrow area. Furthermore, in the process of holding the wire harness with a connector, the connector placed on the mounting table is temporarily fixed by pressing the push pin 23 from above. With the outer surface of the connector in contact with the surface of the mounting stage horizontal, the holding operation of the wire harness with the connector begins. That is, the holding operation of the wire harness with the connector is performed while the connector remains in the same position, thus enabling the connector to be held in a defined position and direction. Even if the connector's direction deviates from the specified direction, the effect of the deviation can be easily eliminated by detecting the amount of deviation and correcting the direction of the robot 1 when inserting the connector into the connector port.

[0050] The shapes of the pair of abutments 41 and 42 can be made into any shape according to the size and shape of the connector. For example... Figure 10 As shown, for example, a pair of pressing parts 81, 82 can also be formed into a Y-shaped planar shape that expands forward as a whole.

[0051] Additionally, to ensure that the wire harness C, which is curved upwards relative to the surface of the mounting platform 7, is arranged as straight as possible, a pair of covers 91, 92 can be provided on a pair of first fingers 31, 32. For example... Figure 11 As shown, for example, a pair of covers 91, 92 are configured as a comb shape that interlocks with each other. As a result, the bulge of the wire harness C can be suppressed within the height of a pair of first fingers 31, 32, which can improve the gripping accuracy of the robot arm 1 on the wire harness with connector.

[0052] In this embodiment, the robotic arm 1 is configured to be equipped with two cameras 61 and 71, but it can also be configured to have only one camera. Additionally, as... Figure 12 As shown, not only can a camera be equipped on the robotic arm 1, but it can also be configured to place a camera at the location of the cable harness with connector on the mounting platform 7, overlooking it.

[0053] Furthermore, as long as the pair of abutting portions 41 and 42 can be pressed against the rear end face of the connector while the wire harness is being held, the structure is not limited to this embodiment. For example, in this embodiment, the robot arm 1 is configured to have two wire clamping mechanisms 30 and 50, but it may also be configured to have three or more wire clamping mechanisms. Alternatively, it may be configured to have a single wire clamping mechanism for holding the wire harness and a mechanism for pressing the abutting portions against the rear end face of the connector.

[0054] While several embodiments of the invention have been described, these embodiments are given by way of example and do not constitute a limitation on the scope of the invention. These embodiments can be implemented in a wide variety of other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments, their variations, and those contained in the scope and spirit of the invention are included within the scope of the invention as described in the claims and their equivalents.

Claims

1. A robotic arm that holds a wire harness with a connector attached to its front end, wherein, have: Hand base, The push-button mechanism, which allows for flexible lifting and lowering, supports the hand base and is used to press the connector onto the mounting platform from above. The front wire clamping mechanism, located behind the push-button, is supported on the hand base and can move freely up and down and back and forth, for clamping the wire harness. The rear wire clamping mechanism, which is freely raised and lowered and supported on the hand base, is used to clamp the wire harness. A pair of abutting parts, a pair of fingers of the wire clamping mechanism located on the front side, are pressed against the connector from the rear; The connector is pressed against the mounting platform by the push-button, thereby making the connector parallel to the mounting platform. The wire harness is held by the wire clamping mechanism on the rear side. With the front wire clamping mechanism moved forward to press the abutment against the connector, the wire harness is clamped and held by the front wire clamping mechanism. When the connector is inserted into the connector port, the push pin is pushed away.

2. The robotic arm according to claim 1, wherein, A connector detection camera is also mounted on the hand base for photographing the connector.

3. The robotic arm according to claim 1 or 2, wherein, An overall inspection camera is also mounted on the hand base for overhead photography of the wiring harness and the connector.

4. The robotic arm according to claim 1 or 2, wherein, The pressing part has a Y-shaped shape that expands forward.

5. The robotic arm according to claim 1 or 2, wherein, The pressing part has a U-shape.

6. The robotic arm according to claim 1 or 2, wherein, In order to suppress the bending of the wire harness within the height of the fingers, a pair of comb-shaped covers that interlock with each other are installed on a pair of fingers of the wire clamping mechanism on the front side.

7. A method for holding a wire harness with a connector, wherein the wire harness is held at its front end with a connector connected thereto, wherein, The position of the wiring harness is detected based on images captured by a camera mounted on the hand base or externally located. The hand base is moved according to the position of the detected wire harness, and the detected wire harness is surrounded by a pair of fingers from the wire clamping mechanism on the front side and the wire clamping mechanism on the rear side of the hand base. The position of the connector is detected based on images captured by the camera, or by another camera mounted on the hand base or located externally. Based on the detected position of the connector, the push-press mechanism supported by the hand base moves forward and backward, causing the push-press pin of the push-press mechanism to descend and press the connector on the mounting platform. The wire harness is held by a pair of fingers of the wire clamping mechanism on the rear side. The front wire clamp mechanism is moved forward, causing a pair of abutments of a pair of fingers on the front wire clamp mechanism to press against the connector being held from behind. The wire harness is held by a pair of fingers of the wire clamping mechanism on the front side. The push-button and the rear wire clamp mechanism are made to avoid the connector and the wire harness.

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