JPH0733590U - Robot gripping device - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention relates to a gripping device for a robot that conveys a conveyed object such as a wheel having an outer peripheral surface having a slippery contact surface with a holding claw by sandwiching it on both outer peripheral surfaces. [Structure] The wheel 10 is attached to the sandwiching arms 1 facing each other.
The holding rollers 3 are provided above the holding claws 2 that sandwich the outer peripheral surface of the transported object. The holding roller 3 is elastically supported by an air cylinder 5 or a spring so that it can project from the front surface of the holding claw 2, and is pressed against the outer peripheral surface of the conveyed product at a position above the contact point of the holding claw. When the holding claw 2 slides, the holding roller 3 slowly slides while pressing the holding surface, and the holding roller 3 engages at the stepped portion of the holding surface to correct the pinching of the holding claw 2.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a gripping device for a robot, which has various shapes of holding surfaces and is slippery, and which conveys a conveyed object such as a wheel by sandwiching it from both sides.

[0002]

[Prior art]

 Conventionally, the gripping device of a robot is sandwiched by holding claws that open and close from both sides, but it is circular and slippery like a tire wheel, and a concave part is formed between the large diameter parts on both sides. If the diameter and shape differ depending on the model, it is necessary to prepare a large number of holding claws that match each shape, which is complicated and wasteful.

Further, when a robot conveys a circular object having a large diameter on both sides such as a tire wheel, since the type of pinching from the top surface of the wheel is not suitable for the robot, the pinching arm is placed horizontally. The wheel is inserted from the lateral direction and opened and closed laterally at right angles to the insertion direction so that it is sandwiched in the radial direction from both sides.If the diameter of the holding surface is different, face the holding arms on both sides respectively. A holding claw with a V-shaped holding surface that is tilted is attached, and the outer peripheral surface is held at four points by this holding claw.

[0004]

[Problems to be solved by the device]

 For this reason, the contact between the inclined surface of the holding claw and the holding surface such as the wheel outer periphery does not occur on a wide surface, but is point contact, even if a slip stopper such as rubber is provided on the contact surface of the holding claw. Is slippery, especially if it is a vertical surface with the same diameter above and below the sandwiched position, or if it is an inclined surface with a small diameter on the upper side, the object to be transported may be shaken during transportation and the large size of the upper side due to slipping of the holding point. There is a drawback that it slips down to the diameter part, impacts the holding claws, scratches the transported goods, and makes the holding unstable.

Further, when the conveyed object is clamped in a tilted state, as shown in FIG. 5, since the holding claws 2 are horizontally clamped, the distance a between the clamping points becomes larger than the diameter b of the clamping portion, and When the object is lifted, the transported object slips by its own weight, causing the same problem as described above.

[0006]

[Means for Solving the Problems]

 According to the present invention, in such a gripping device of a robot, a holding roller elastically supported so as to project from the front surface of the holding claw is provided above the holding claw, and the holding claw is used to hold the holding claw by a holding arm. When brought into contact with the outer peripheral surface, the holding roller is configured to come into pressure contact with the outer peripheral surface of the conveyed product above the contact point of the holding claw.

[0007]

[Action]

 For this reason, even if there is slippage between the conveyed product and the holding claws due to vibration during conveyance or due to being clamped in an inclined state, the holding roller rolls to the large-diameter step while pressing the outer peripheral surface of the conveyed product under pressure. , Prevents a sudden drop of the transported object and stabilizes the gripped state.

[0008]

【Example】

 This will be described with reference to the embodiment shown in the drawing. Reference numerals 1 and 1 denote sandwiching arms, and holding claws 2 are attached to the front and the rear, respectively. Reference numeral 3 is a holding roller provided above the holding claw, and 4 is a support pin of the holding roller 3, through which the holding arm 1 is slidably inserted and fixed to the connecting plate 5. Reference numeral 6 denotes an air cylinder attached to the holding arm 1. The operation shaft 7 of the air cylinder is fixed to the connecting plate 5, and the front and rear support pins 4 are pushed out at the same time. Reference numeral 8 is a guide pin attached to the connecting plate 5, and 9 is an opening / closing device for the holding arm 1, which is attached to the robot arm.

Reference numeral 10 denotes a wheel, which has large-diameter portions 11 on both sides of the outer peripheral surface thereof and concave portions 12 between the large-diameter portions, and the concave portions 12 are configured in various shapes. A step portion 14 is provided at 13 and its end.

The opening / closing operation device 9 is operated to draw the holding arms 1 and 1, and the holding claws 2 are brought into contact with the recesses 12 of the wheel 10 to hold them. By this operation, for example, as shown in FIG. 3, each holding claw 2 comes into contact with the inclined surface 13 of the wheel 10 and holds it at four places, and each holding roller 3 is positioned above the holding claw 2 and the inclined surface 13 is held. Is pressed by the pulling force of the air cylinder 6.

When the contact point of the holding claw 2 is slipped, the clamping operation of the holding arms 1 and 1 by the opening / closing operation device 9 cannot be performed in time and the tightening is loosened, but the holding roller 3 is located above the contact point. Since it is pressed against the inclined surface 13 separately from, the holding roller 3 rotates and slides at a low speed while holding the pressing force due to the pulling force of the air cylinder 6, and is stopped and held by the step portion 14. During this time, the holding claw 2 operates the clamping arm 1 to correct and move the holding claw 2 in response to the decrease in the contact pressure with the inclined surface 13, and the holding claw 2 is brought into contact with the inclined surface to move the wheel 10. To support.

Further, when the holding claws hold the wheel 10, if the wheel 10 is inclined as shown in FIG. 5, the right side of the drawing falls when the holding claws hold only the holding claws. Since the holding roller 3 is pressed against the outer peripheral surface of the wheel, the wheel 10 is prevented from being suddenly dropped due to the slip of the holding claw 2 and is smoothly moved to the stepped portion to be held in a horizontal state.

FIG. 4 shows another supporting device for the holding roller 3, in which the holding claw 2 is formed integrally with the holding piece 20, and is supported by the bracket 21 of the holding arm 1 by the pivot 22 to support the wheel 10. It rotates according to the size so that the contact surface of the holding claw is in the cutting line direction of the wheel, the support pin 4 of the holding roller 3 inserts the holding piece 20, and the spring receiver 23 and the holding piece 20 A spring 24 is interposed between the holding roller 3 and the holding roller 3 so as to be pressed against the outer peripheral surface of the wheel. 25 is a retaining piece.

In this embodiment, the holding rollers 3 are individually pressed into contact with the outer peripheral surface of the wheel by the springs 24 and are not connected to other holding rollers. Depending on the diameter of the wheel, the holding roller 3 is rotated together with the holding claw 2 so that the holding roller is always pressed toward the center of the wheel even if the diameter of the wheel, which is the conveyed object, is different from that of the wheel outer peripheral surface. To improve the contact condition.

[0015]

[Effect of device]

 As described above, the present invention elastically supports the holding claws attached to the opposing holding arms so that the holding claws can project from the front surface of the holding claw, and conveys the objects above the contact point between the conveyed object and the holding claw. Since the holding roller is provided on the outer peripheral surface of the object separately from the holding claw, the holding roller presses the conveyance roller even if the conveyed item and the holding claw slip at the contact part and the conveyed item falls. Sliding at a low speed to the stepped portion of the object recess to prevent impact on the holding claws and damage to the conveyed object, and the holding roller engages with the stepped portion to support the conveyed object for stable holding, and the outer periphery of the conveyed object. Even if the shape of the surface changes, the gripping device can be securely held by the common gripping device, and the versatility of the gripping device can be obtained.

Further, even when the position of the conveyed product is inclined when the conveyed product is clamped, the holding roller operated separately from the holding claw at the upper part of the holding claw is always in pressure contact with the outer peripheral surface of the conveyed product. Thus, there is an effect that a sudden fall of the conveyed object due to the slip of the holding claw when lifted up can be prevented, and the holding claw can be held securely in a horizontal state.

If the holding roller is brought into pressure contact with the conveyed product with a spring, the structure for elastically supporting the holding roller can be simplified and integrated with the holding claws to hold the conveyed product even when the diameter of the conveyed product is different. The roller can be pressed against the center of the conveyed product to ensure the holding.

[Brief description of drawings]

FIG. 1 is a top view showing an embodiment of the present invention, a part of which is shown in section.

FIG. 2 is an enlarged side sectional view taken along the line AA of FIG.

FIG. 3 is an explanatory diagram showing an example of a contact state with a wheel.

FIG. 4 is a partial side view showing another embodiment.

FIG. 5 is an explanatory diagram showing a gripped state when a wheel is tilted.

[Explanation of symbols]

 1 Clamping Arm 2 Holding Claw 3 Holding Roller 4 Support Pin 5 Connecting Plate 6 Air Cylinder 7 Operation Axis 8 Guide Pin 9 Opening / Closing Device 10 Wheel 11 Large Diameter Part 12 Recess 13 Slope 14 Step 20 Clamping Piece 21 Bracket 22 Axis 23 Spring holder 24 Spring 25 retaining piece

Claims (4)

[Scope of utility model registration request] 1. A gripping device of a robot for opening and closing opposing holding arms, and holding a holding claw attached to the holding arm by laterally contacting a holding surface and holding the holding claw, above the holding claw, the front surface of the holding claw respectively. It is elastically supported so that it can protrude from the holding surface, has a holding roller that presses against the holding surface at a position above the holding claw that comes into contact with the holding surface, and a step portion having a diameter larger than the holding surface is provided above the holding surface. A unique robot gripping device. 2. The robot gripping device according to claim 1, wherein the holding roller is supported by a support pin that is inserted into a holding arm, and the holding roller includes an air cylinder that presses the support pin in a contact direction. 3. The robot gripping device according to claim 1, wherein the holding roller includes a spring that presses the support pin in a contact direction. 4. The gripping device for a robot according to claim 1, wherein the holding claw is attached so as to rotate according to the diameter of the conveyed object, and the holding roller is attached integrally with the holding claw.