JP2011073135A - Chuck and robot hand - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a robot hand and a chuck coping with holding of various kinds of workpieces with a relatively simple and lightweight structure. <P>SOLUTION: The chuck is composed of a chuck holder 1, an operation rod 2 and a chuck claw 3, wherein the chuck holder 1 is equipped with: a notch 7 for rockably storing the chuck claw 3 for satisfying the holding opening function of the work; and a rocking fulcrum for supporting a base part 3b back face of the chuck claw 3. The operation rod 2 includes a pressurizing part 8 projecting to the side in its tip part, and is inserted into a hollow part of the chuck holder 1 so as to advance and retreat. A base part 3b of a plurality of chuck claws 3 is sandwiched at a rocking fulcrum between the pressurizing part 8 of the operation rod and the chuck holder 1. A cam part 9 is provided, on an inner surface of the base part 3b of the respective chuck claws 3, which converts an advance-retreat quantity of the pressurizing part 8 caused by an advance-retreat of the operation rod 2 into a rocking quantity in the centrifugal and centripetal direction of the respective chuck claws 3. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a chuck and a robot hand used for an assembly operation, a processing operation, or a conveyance operation by an automatic machine.

The robot hand has a complex structure in which a plurality of various actuators and mechanical parts are combined in order to stably hold the workpiece. For this reason, there is a limit to reducing the size of the robot hand, and it has been difficult to hold a fine workpiece.
Conventionally, there is a method called an air balloon chuck, but there is a great limitation on the size and shape of the workpiece to be chucked.

Further, each time the process is changed, it is necessary to arrange a necessary number of robots or to replace the chuck according to the purpose of the process.
In order to solve this problem, a method in which a plurality of robot hands and mechanical parts are provided, or a method in which an ATC mechanism is provided and the chuck portion is replaced each time has been adopted.

JP 2009-066673 A

However, as the robot arm-related mechanism becomes more complicated, the control mechanism becomes more complicated (see, for example, Patent Document 1 below), and it is necessary to place a controller or the like for controlling them in a portion other than the hand. As a result, not only the housing portion becomes large, but also the wiring and piping increase, and the structure of the joint portion that connects the robot hand and the robot arm becomes complicated, so the entire apparatus inevitably becomes large.
In addition, when the weight of the robot arm increases, it is required to balance the robot arm, resulting in a problem that the movement speed of the robot arm is relatively slow.

  Further, when controlling the holding force of the chuck, a pressure sensor or the like must be attached to the tip of the robot hand, and there is a problem that it is difficult to realize a small, lightweight and inexpensive robot hand.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a robot hand and a chuck that can handle various workpieces and the like with a relatively simple and lightweight structure.

  The chuck according to the present invention, which has been made to solve the above problems, comprises a chuck holder, an operating rod, and a chuck claw, and the chuck holder has a notch in which the chuck claw can be swung so as to satisfy the work holding and releasing function. The rocking fulcrum that supports the back of the base of the chuck claw is provided, and the operation rod has a pressurizing part or magnet core that protrudes laterally at the tip, allowing the operation rod to advance and retreat in the hollow part of the chuck holder. Inserting, holding the base of the plurality of chuck claws at the pressurizing part of the operating rod or the rocking fulcrum of the magnet core and the chuck holder, and the pressurizing part accompanying the advancement and retraction of the operating rod on the inner surface of the base of each chuck claw A cam portion is provided that converts the amount of advancement and retraction of the magnet core into a swing amount of each chuck claw in the centrifugal direction and the centripetal direction.

  The chuck holder has a notch that allows the base of the chuck claw to be swingable. One or a plurality of desired angular intervals along the longitudinal direction of the chuck ring (an interval suitable for the size and shape of the workpiece. And a support groove that crosses the notch and goes around the chuck holder on the outer surface of the chuck holder, and the support groove is loaded with a fulcrum ring that serves as a swing fulcrum of the chuck claw. .

  A chuck ring that covers a base portion of the chuck claw that fits in the notch of the chuck holder and a fulcrum ring that is loaded in the support groove of the chuck holder may be attached to the lower portion of the chuck holder.

  Further, as one of the structures having a chuck ring that covers the side of the chuck holder, the chuck claw includes a protrusion that fits on a swing fulcrum on the back surface of the base, and the chuck ring is formed by a pair of upper and lower rings. The inside of the lower end of the upper chuck ring and the upper end of the lower chuck ring is chamfered, and each is provided with an inward inclined surface. It is also possible to form a rocking fulcrum that accommodates the protrusions, and the upper and lower rings are in close contact with each other and fixed to the chuck holder to support the base of the chuck claw that fits in the notch of the chuck holder from the outside.

  It is also possible to adopt a structure in which an accommodation hole is provided in the base of the chuck claw, and an elastic rattling stopper having a thickness equal to or larger than the width of the notch of the chuck holder is loaded in the accommodation hole.

  In addition, in order to hold | maintain the thing which should be hold | maintained with a suction force or to reinforce a holding force, it is good also as a structure provided with the suction nozzle connected to the said hollow part at the front-end | tip part as an operating rod. Further, the sensor head may be fixed to the tip of the operation rod through the hollow portion so as to give the chuck the function of detecting the presence or absence of an object, light, pressure, or the like.

  Similarly, the operation rod may be rotatably supported with respect to the chuck holder in order to operate the operation rod with respect to the rotation of the chuck.

  The robot arm according to the present invention, which has been made to solve the above problems, rotatably supports a chuck holder that rotatably supports the operation rod on the arm housing, and advances and retracts the operation rod relative to the arm housing. It is characterized by comprising a chuck comprising elevating means and rotation transmitting means for rotating the chuck holder.

  In a robot arm that rotatably supports a chuck having a structure including a suction nozzle connected to the hollow portion at the tip, the airtightness of the outer space between the chuck holder and the bearing portion is provided in the bearing portion that supports the chuck holder. The chuck holder is provided with a means for ensuring airtightness of the inner gap between the operation rod and the chuck holder, and the operation rod is a hollow member, and a through-hole for communicating the hollow portion with the inner gap. The chuck holder may have a structure that includes a through hole that allows the inner gap and the outer gap to communicate with each other, and that the arm casing includes an air path that allows the outer gap and the outlet of the arm casing to communicate with each other.

  In order to adjust the holding force of the chuck, the elevating means may be one in which a piston rod of a cylinder mechanism that moves back and forth substantially in parallel and an operation rod of the chuck are connected by a transmission arm.

  As the elevating means, two or three cylinder mechanisms may be provided in which each piston rod advances and retreats in parallel and is connected to each other. At that time, it is assumed that all the cylinder mechanisms and the operating rods are arranged in a substantially linear manner, and the operating rods are arranged at their ends. The cylinder mechanism may be built in the arm casing in a form in which the arm casing itself is a member of the cylinder mechanism.

  In order to give an elastic width to the holding force of the chuck, the transmission arm may be composed of a plurality of leaf springs that are stacked with an interval in the advancing and retreating direction of the operating rod. Furthermore, it is good also as a structure provided with the load adjustment member which connects and supports the said several leaf | plate spring so that position adjustment is possible in a part of longitudinal direction so that the holding force of a chuck | zipper may be adjusted.

The robot hand according to the present invention is provided with a plurality of cylinders in the robot arm housing, the transmission arms and fulcrums are provided in the cylinders, and the opening and closing dimensions of the chuck tip are controlled by changing the combination of supplying air to each cylinder. The holding force is adjusted.
Because of this configuration, the holding dimensions and holding force of the chuck can be controlled simply by controlling a plurality of cylinders provided in the robot arm housing, making it smaller, lighter and less expensive than conventional robot hands. It can be. Further, since the number of parts used can be reduced, there is an advantage that maintenance and adjustment are easy.
As described above, the configuration in which a plurality of cylinders and chucks are arranged in series is particularly effective for a rotary robot arm.

  The structure of the transmission arm is provided with two leaf springs, and a load adjustment member that can slide is attached, so that the holding force can be controlled via the transmission arm consisting of leaf springs, so fine pressure adjustment can be performed, for example, air In the case of a cylinder, the holding force can be controlled relatively easily by adjusting the position of the load adjustment member attached to the leaf spring without using an expensive electropneumatic regulator to control the air pressure. There are advantages you can do.

  By providing a suction nozzle that is exposed in the open state at the tip of the chuck, holding using vacuum suction becomes possible.

It is sectional drawing which shows an example of the chuck | zipper by this invention. It is sectional drawing which shows an example of the chuck | zipper by this invention. It is sectional drawing which shows an example of the robot arm by this invention, and is explanatory drawing which shows the state of control of a holding | maintenance dimension. It is sectional drawing which shows an example of the robot arm by this invention, and is explanatory drawing which shows the state of control of holding force. It is sectional drawing which shows an example of the robot arm by this invention, and is explanatory drawing which shows the operation state of an adsorption | suction means. It is sectional drawing which shows an example of the robot arm by this invention, and is explanatory drawing which shows the operation state of a rotation transmission means. It is a front view which shows the example of the chuck | zipper by this invention. An example of the holding | maintenance aspect of the chuck | zipper by this invention is shown, (A) is a perspective view, (B) and (C) are sectional drawings. An example of the holding | maintenance aspect of the chuck | zipper by this invention is shown, (A) is a perspective view, (B) is a top view of the workpiece | work which should be hold | maintained, (C) is a longitudinal cross-sectional view of (A). It is an exploded view which shows an example of the robot arm by this invention. It is sectional drawing which shows an example of the robot arm by this invention. It is a table | surface which shows an example of the control form of the holding | maintenance dimension and holding force of the robot arm shown in FIG. It is a perspective view which shows an example of the robot arm by this invention, and is a perspective view which shows an example of the structure which detects the load which arises by hold | maintaining a workpiece | work with a chuck | zipper. It is a side view which shows an example of the robot arm by this invention, and is explanatory drawing which shows an example of the structure which detects the load which arises by hold | maintaining a workpiece | work with a chuck | zipper. It is an exploded view showing an example of means for detecting a load generated by holding a workpiece with a chuck. It is sectional drawing which shows an example of the chuck | zipper by this invention. An example of the robot arm by this invention is shown, (A) is a side view, (B) is the principal part sectional drawing. An example of the chuck | zipper by this invention is shown, (A) is a side view, (B) is a longitudinal cross-sectional view of the state which rotated (A) 90 degree | times. An example of the chuck according to the present invention is shown, (A) is a perspective view seen from obliquely below, (B) is a perspective view showing a state in which the chuck ring of (A) is half removed. It is a rear view which shows an example of the front part of the robot arm by this invention. It is sectional drawing which shows the example of arrangement | positioning of the air path | route of the robot arm by this invention.

  Embodiments of a chuck according to the present invention and a robot hand using the chuck will be described below with reference to the drawings.

[About chuck]
1, 2, and 7 includes a chuck claw 3, a chuck holder 1, and an operation rod 2.

  The chuck claw 3 is formed by integrally forming the working part 3a and the base part 3b, and the amount of advancement / retraction of the pressurizing part 8 accompanying the advance / retreat of the operating rod 2 is determined on the inner surface of the base part 3b of each chuck claw 3 in the centrifugal direction of each chuck claw 3. And the cam part 9 converted into the amount of rocking in the centripetal direction is provided. In this example, the working portion 3a is tapered and the inner surface is flat, and the cam portion 9 is curved and recessed, and the chuck claw 3 is prevented from being displaced in the vertical direction on the front side (back portion center) of the center portion of the recess. Then, a support groove 10 for accommodating the fulcrum ring 11 which is the swing fulcrum of the chuck claw 3 is provided over the entire width.

  The chuck holder 1 has a cylindrical pipe portion 1a having a common central axis that communicates with a hollow portion having a circular cross section, and a cylindrical shape having a wider diameter than that of the pipe portion 1a, and an outer side at the lowermost end. The holder portion 1b having the flange portion 1c that is widened is integrally connected.

  The holder part 1b of the chuck holder 1 is provided with a notch (or groove) 7 along the longitudinal direction of the chuck holder 1 so that the base part (particularly the back part) 3b of the chuck claw 3 can swing freely. A plurality (same as the number of chuck claws 3) are formed at substantially equal angular intervals, and the notches 7 are formed on the outer surface of the holder portion 1b (in the example, along the upper outer edge of the flange portion 1c). The support groove 10 that crosses the entire circumference of the chuck claw 3 is drilled over the entire circumference, and a fulcrum ring 11 that serves as the swing fulcrum of the chuck claw 3 is loaded in the support groove 10 (see FIGS. 2 and 7).

  With this configuration, the chuck claw 3 can satisfy the function of holding and releasing the workpiece 6, and the chuck claw 3 supported by the fulcrum ring 11 can be prevented from being laterally displaced along the fulcrum ring 11.

Further, the chuck ring 5 can be mounted for the purpose of stabilizing the fulcrum ring 11 and preventing the fulcrum ring 11 from being detached from the holder portion 1b.
The chuck ring 5 has a cylindrical shape with a diameter through which the pipe portion 1a of the chuck holder 1 is inserted and stays around the holder portion 1b, and has an inner diameter that advances and retreats around the holder portion 1b. Depending on the shape of the flange portion 1 c of the chuck holder 1, a notch portion into which the flange portion 1 c is fitted may be provided on the lower inner peripheral edge of the chuck ring 5.
When the chuck ring 5 stays around the holder portion 1b, the chuck ring 5 covers the base 3b of the chuck claw 3 that fits in the notch 7 of the holder portion 1b and the fulcrum ring 11 loaded in the support groove 10 of the chuck holder 1, The fulcrum ring 11 is supported from the outside.

  If this structure is employed and a fulcrum ring 11 with ends is cut or notched at one endless ring, or a ring with an endless ring cut in half, the elasticity is used to make the chuck 4 A certain margin can be given to the size of the object to be held, and it is easy to remove it. By removing the fulcrum ring 11, the chuck claw 3 can be easily removed and replaced.

  Further, in this configuration, each chuck claw 3 swings while being supported on the inner side of the cut 7, so that left and right blur does not occur. Further, the rigidity of the chuck claw 3 can be complemented by the holder portion 1b that sandwiches the notch. From the above structure, even if the width of the chuck claw 3 is reduced to, for example, about 0.1 mm depending on the material, it is possible to accurately apply force to the object to be held, and it is extremely fine. It can also be used for holding the workpiece 6.

The operating rod 2 is a cylindrical pipe having a thickness that advances and retreats the hollow portion of the chuck holder 1.
The operation rod 2 includes a pressurizing portion 8 that presses the cam portion 9 of the chuck claw 3 at a tip portion thereof. The pressure part 8 in this example has a rotary bearing fixed in a bowl shape as a pressure ring 8a projecting sideways, supports the pressure ring 8a at the tip so as not to be detached, and is joined to the surface of the cam part. 9 is attached with a tapered cap 8b along the surface shape. With this configuration, the surface of the pressurizing unit 8 follows the curved surface of the surface of the cam unit 9, and gives a stable opening amount with no play to the chuck claw 3 while corresponding to the rotation of the operation rod 2. It becomes.

The operating rod 2 is inserted into the hollow portion of the chuck holder 1 so as to be able to advance and retreat, and to freely rotate. The chucking ring 5 or the fulcrum ring 11 of the chuck holder 1 and the pressurizing portion 8 of the operating rod 2 The base portions 3b of the plurality of chuck claws 3 are sandwiched. With such a configuration, a predetermined number of chuck claws 3 are held inside the chuck ring 5 under the same conditions.
The chuck claws 3 held in this way are moved to the base portions 3b of the chuck claws 3 as the operating rod 2 moves back and forth, so that the tip ends of the chuck claws 3 held by the chuck ring 5 are shifted. The opening of (working unit 3a) is adjusted.

  The embodiment shown in FIG. 16 has the opposite effect to the embodiment shown in FIGS. 1 and 2. That is, the operation rod 2 of the embodiment includes a magnet core 22 that attracts the cam portion 9 of the chuck claw 3 made of a magnetic material, instead of the pressurizing portion 8, at the distal end thereof.

  The operation rod 2 is inserted into the hollow portion of the chuck holder 1 so as to be able to move forward and backward, and can be freely rotated. The chuck ring 5 or the fulcrum ring 11 of the chuck holder 1 and the magnet core 22 of the operation rod 2 can be connected to a plurality of swing fulcrums. By sandwiching the base portion 3b of the chuck claws 3, a predetermined number of chuck claws 3 are held in the chuck ring 5 under the same conditions.

The chuck claw 3 held in this way receives the magnetic force of the magnet core 22 at the cam portion 9 as the operating rod 2 advances and retreats. In other words, the opening and closing of the working portion 3 a of each chuck claw 3 held by the chuck ring 5 is adjusted by shifting the drawing area in the cam portion 9 of the chuck claw 3.
As a result, the work part 3a of the chuck claw 3 closes when the magnet core 22 approaches the work part 3a, and the work part 3a of the chuck claw 3 opens when the magnet core 22 approaches the base part 3b.

[About robot arm]
The robot arm shown in FIGS. 3 to 6 rotatably supports the chuck holder 1 of the chuck 4 on a bearing portion (see FIG. 10) 17 of the arm housing 13.

The bearing portion 17 includes a rotary bearing 17a that is in contact with the outer surface of the chuck holder 1, and the chuck holder 1 supported by the bearing portion 17 has a pulley 18 for receiving a rotational force at its upper portion as one of the rotation transmission means. As an integral part.
The rotation transmitting means refers to a member or a combination of members that transmits a force used for rotating the chuck to the chuck.

  The bearing portion 17 of the arm housing 13 includes a ring-shaped protruding portion 23 having a narrowed inner diameter at the middle portion of the inner wall of the shaft hole penetrating vertically. A rotary bearing 17a is mounted on the upper and lower sides of the protruding portion 23 in the shaft hole, and a pulley 18 and a lock ring 18a for preventing them from being detached are mounted on the upper rotary bearing 17a (see FIG. 10).

Further, the operation rod 2 is inserted from above, and one or more bushes 24 and the chuck ring 5 are attached to the rotary bearing 17 a below the protruding portion 23 and inserted into the chuck holder 1.
As described above, the rotary bearing 8a is attached to the tip of the operation rod 2 as the pressure ring 8a. As shown in FIG. 10, the nut 25 is screwed into the tip of the control rod 2 to support the rotary bearing 8a. It may be fixed with.

Various members can be attached to the chuck in order to achieve holding and other purposes.
For example, the operating rod 2 shown in FIG. 1 to FIG. 7 includes a suction nozzle 12 connected to the hollow portion at the tip thereof, and by setting the hollow portion to a sufficient negative pressure, an object to be held by the chuck is obtained. It can be used as an adsorbing means that adsorbs and holds or supplements the holding force.
For example, as shown in FIG. 10, a fiber sensor 26 that detects a specific object is inserted into the hollow portion of the operation rod 2, and a lens 26 a that passes the light projected to the tip of the operation rod 2 and the received light is inserted. You may mount | wear (refer FIG. 17).

  The robot arm includes an elevating means for moving the operation rod 2 back and forth in the arm housing 13. The elevating means is obtained by connecting a piston rod 14 a of the cylinder mechanism 14 that advances and retreats in parallel with each other and an operation rod 2 of the chuck 4 by a transmission arm 15. The raising / lowering means in the example is two cylinder mechanisms 14 arranged in a substantially linear side-by-side manner on the arm housing 13. The piston rods 14 a of the two cylinder mechanisms 14 are connected at their exposed portions by a cylinder link 19 so as to be vertically swingable, and fix one end of the transmission arm 15 to the cylinder link 19. The other end of the transmission arm 15 is connected to the exposed portion of the operation rod 2 so as to be vertically swingable.

  Both ends of the cylinder link 19 in this example are divided into two branches, and each arm divided into two branches has a hole through which a connecting pin is inserted. By sandwiching the exposed portion of the piston rod 14a between the crotch gap of the cylinder link 19, and passing the operating rod 27 through the hole provided in the exposed portion of the piston rod 14a and the holes provided at both ends of the cylinder link 19, both The exposed portions of the piston rod 14a are connected to each other.

  The transmission arm 15 is two leaf springs 15a that are stacked in parallel with a gap in the forward / backward direction of the operating rod 2 substantially. A plurality of spacers 20 are interposed between the leaf springs 15a, and the first spacer 20 is fixed to the cylinder link 19 together with one end portions of the two leaf springs 15a. The second spacer 20 is fixed to the other end portion of the two leaf springs 15a, and the front side of the second spacer 20 at the other end portion of the leaf spring 15a is slidably connected to the operation rod 2.

  The tip of each leaf spring 15a in this example is divided into two forks, and the exposed portion of the operation rod 2 is sandwiched between the crotch gaps. The operating rod 27 is fixed horizontally to the exposed portion of the operating rod 2, and the operating rod 27 is sandwiched between the tip portions of the upper and lower plate springs 15a.

  Further, the load adjusting member 16 is fixed so that the position can be adjusted in the region between the first spacer 20 and the second spacer 20, and the two leaf springs 15a are fixed by the first spacer and the second spacer. It is appropriately connected and supported by a part of the sandwiched longitudinal direction.

  If the load adjusting member 16 is moved closer to the operating rod 2 as shown in FIGS. 3, 5, and 6, the unity at the point of action of the two leaf springs 15a increases, and the two leaf springs 15a aggregate As a result, the movement of the cylinder mechanism 14 is transmitted to the operating rod 2 in a rigid manner. On the other hand, if the load adjusting member 16 is moved away from the operation rod 2 (see FIG. 4), the independence of the two leaf springs 15a is increased, and the elasticity of the two leaf springs 15a is increased, whereby the operation rod is increased. 2, the movement of the cylinder mechanism 14 is elastically transmitted. The load resistance of the chuck 4 can be adjusted by adjusting the position of the load adjusting member 16 as described above.

  Each cylinder mechanism 14 is housed in the arm housing 13. That is, the arm housing 13 of this example is formed by molding synthetic resin, aluminum alloy or the like into a square bar shape, and includes two vertical holes (cylinder chambers 14b) for incorporating the cylinder along the longitudinal direction thereof. Furthermore, a bearing portion 17 is provided on the distal end side on the extension line connecting both the cylinder chambers 14b, 14b (see FIGS. 3 to 6 and FIG. 10).

  A timing belt 21 is passed over the arm housing 13 as a rotation transmitting means for rotating the chuck holder 1 of the chuck. The timing belt 21 is hung on a pulley 18 of the chuck holder 1 and a relay pulley through a rotational force generated by a motor as a rotational driving means or another rotational driving means installed (not shown).

Hereinafter, a basic control mode of the robot arm will be described.
FIG. 3 (A) shows the state of the lifting / lowering means that narrows the distance between the tips of the chuck claws 3 (hereinafter referred to as holding dimensions). In this case, of the two cylinder mechanisms 14, the cylinder mechanism (hereinafter referred to as the first cylinder) 14 farther from the chuck 4 minimizes the protruding amount of the piston rod 14 a, and the cylinder mechanism closer to the chuck 4 ( Hereinafter, it is referred to as a second cylinder.) The protrusion amount of the piston rod 14a of 14 is maximized. That is, the angle formed by the arm housing 13 and the transmission arm 15 is maximized. By doing so, the protruding amount of the operating rod 2 from the chuck 4 is maximized, and the pressurizing portion presses the most end portion of the cam portion 9 of the chuck claw 3. The minimum holding dimension can be adjusted by preparing various chuck claws 3 having different forms.

  FIG. 3B shows a state of the lifting means in which the holding dimension is increased by one step from the minimum holding dimension. In this case, the amount of protrusion of both the first cylinder and the second cylinder is maximized while the arm housing 13 and the transmission arm 15 are kept parallel.

  FIG. 3 (C) shows the state of the lifting / lowering means with the holding dimension further widened. In this case, the protruding amount of both the first cylinder and the second cylinder is minimized while the arm housing 13 and the transmission arm 15 are kept parallel.

  FIG. 3D shows a state of the lifting / lowering means that maximizes the holding dimension. In this case, the protrusion amount of the piston rod 14a of the first cylinder is maximized, and the protrusion amount of the piston rod 14a of the second cylinder is minimized. That is, the angle formed by the arm housing 13 and the transmission arm 15 is maximized with an inclination opposite to the minimum holding dimension. By doing so, the protruding amount of the operating rod 2 from the chuck 4 is minimized, and the pressurizing portion 8 presses the most distal portion of the cam portion 9 of the chuck claw 3.

  The cylinder mechanism 14 may be constituted by three columns (see FIG. 11). As shown in FIG. 12, the cylinder a, the cylinder b, and the cylinder c are separated from the chuck 4 by a combination of individual controls of the three cylinder mechanisms. Controls the holding dimension (opening / closing amount) and holding force (opening / closing force) of the variation. In the table, the arrow indicates the position of the piston rod 14a. When the arrow is upward, it is an upper position, when the arrow is downward, it is a lower position, and when two arrows are indicated, it is an intermediate position. The blank indicates that the piston rod 14a is free.

  Simultaneously with the control of the holding dimension, the suction nozzle 12 or the lens 26a provided at the tip of the operation rod 2 can be advanced and retracted as the operating rod 2 advances and retracts. In this example, when the holding dimension of the chuck claw 3 is maximized, the suction nozzle 12 or the lens 26a is most advanced and exposed from between the chuck claws 3 (FIG. 3D, FIG. 5, and FIG. 6). , And FIGS. 10 and 17).

  Further, as described above, the transmission arm 15 is constituted by the two leaf springs 15a which are overlapped in parallel in the forward / backward direction of the operation rod 2 and the spacer 20 interposed between the two leaf springs 15a. Thus, a structure for detecting a load generated by holding the workpiece with the chuck (hereinafter, referred to as a holding load detection structure) can be obtained.

The base ends of the two leaf springs 15 a are fixed to the cylinder link 19 together with the spacer 20. The distal end portion of the transmission arm 15 is connected to the exposed portion of the operation rod 2 so as to be vertically swingable.
The tip of each leaf spring 15a in this example is divided into two forks, and the exposed portion of the operation rod 2 is sandwiched between the crotch gaps. The operating rod 27 is fixed horizontally to the exposed portion of the operating rod 2, and the operating rod 27 is sandwiched between the tip portions of the upper and lower plate springs 15a.

  One of the upper and lower leaf springs (lower leaf spring in the example shown in FIG. 15) is mounted with a circuit board 29 having a cable 31 for mounting the Hall element 28 and taking out the output, and the other leaf spring. (In the example shown in FIG. 15, the upper plate spring) A support hole 15b is formed at a position facing the hall element 28 of 15a, and the magnet grain 28a is pressed by the installation pressing plate 30 (see FIGS. 13 to 15).

  According to the holding load detection structure configured as described above, if the lower leaf spring 15a bends due to the load caused by holding the workpiece 6, the load change such as the distance between the Hall element 28 and the magnet grain 28a increases. As a result, the electrical signal extracted from the Hall element 28 changes. According to this change, the operation of the cylinder mechanism 14 can be adjusted so that the robot arm performs an operation set to a desired holding force or the like at a desired position.

  Hereinafter, other embodiments of the chuck according to the present invention and a robot hand using the chuck will be described with reference to the drawings.

[About chuck]
The chuck shown in FIGS. 18 to 21 includes a chuck claw 3, a chuck holder 1, and an operation rod 2.

  As in the previous embodiment, the chuck claw 3 is formed by integrally forming the working portion 3a and the base portion 3b, and the amount of advancement / retraction of the pressurizing portion 8 associated with the advancement / retraction of the operating rod 2 is set on the inner surface of the base portion 3b of each chuck claw 3. A cam portion 9 is provided for converting the amount of rocking of each chuck claw 3 into the centrifugal direction and the centripetal direction. In this example, the working portion 3a is tapered and the inner surface is flat, and the cam portion 9 is curved and recessed.

  In the chuck claw 3 of the present embodiment, the protrusion 3c that fits on the swinging fulcrum of the chuck claw 3 and prevents the chuck claw 3 from shifting in the vertical direction on the front side (center of the back portion) of the center of the recess extends over the entire width. And an accommodation hole (which may be partly cut out) 33 for mounting the rattling stopper 32 on the end surface of the base portion 3b. In this example, the rattling stop 32 is equal to the width of the notch 7 of the chuck holder 1 or slightly thicker than the width of the notch 7 (thickness that does not hinder the control of the chuck pawl 3). A tube-like or spherical one made of fluorine resin or the like is used.

  The chuck holder 1 of the present embodiment is a holder having a cylindrical pipe portion 1a and a cylindrical shape having a wider diameter than that of the pipe portion 1a and having a flange portion 1c widened outward at the uppermost end. The portions 1b are integrally connected in such a manner that the hollow portions having respective circular cross sections communicate with each other and have a common central axis.

  The pipe portion of the chuck holder 1 has a diameter to which the rotary bearing 17a can be mounted, and has a through hole 1f connected to the hollow portion in the middle portion thereof. The holder portion 1b of the chuck holder 1 is a base portion (particularly, a chuck claw 3). A plurality of notches (or grooves) 7 along the longitudinal direction of the chuck holder 1 are provided over the entire circumference of the holder portion 1b (chuck) so that the back portion 3b can be swung freely along the radius of the holder portion. The fixing holes 1e are provided on the end faces of one or a plurality of blocks 1d provided at substantially equal angular intervals or a desired interval and separated by the cuts 7 (see FIG. 19).

  In the present embodiment, the chuck ring 5 is further mounted for the purpose of holding the protrusion 3c of the chuck claw 3 and preventing the chuck claw 3 from being detached from the holder portion 1b.

The chuck ring 5 includes a pair of upper and lower rings 5 a and 5 b and has a relatively shallow cylindrical shape that can be slidably mounted around the holder portion 1 b of the chuck holder 1. The upper chuck ring 5a is in contact with the flange 1c of the chuck holder 1, the lower chuck ring 5b is in contact with the upper chuck ring 5a, and the upper and lower chuck rings 5a and 5b are in close contact with each other. Secure to.
The chuck ring 5 is fixed to the chuck holder 1 with an attachment screw 34 screwed into the fixing hole 1e.

The lower end of the upper chuck ring 5a and the upper end of the lower chuck ring 5b are each provided with inclined surfaces that are chamfered at the same depth, and the chuck rings 3a and 5b are brought into close contact with each other so that the chuck claw 3 A support groove 5c in which all or a part of the protrusion 3c is accommodated is formed.
When the chuck ring 5 stays around the holder portion 1b, the chuck ring 5 supports the base portion 3b of the chuck claw 3 that fits in the notch 7 of the holder portion 1b from the outside.

With this configuration, the chuck claw 3 functions to hold and release the workpiece 6.
In this way, by adopting a configuration that does not use the fulcrum ring 11, in addition to the effects of the other embodiments described above, the mounting operation of the fulcrum ring 11 that was relatively difficult can be avoided, and the accuracy of the fulcrum ring can be avoided. Therefore, the amount of positional deviation caused by warping, bending, or variation in mounting position is reduced, and rattling of the chuck pawl 3 can be reduced.

Further, by mounting the rattling stopper 32 in the accommodation hole 33, the change in the opening / closing amount of the chuck jaw 3 caused by the rattling of the cam portion 9 and the pressure ring 8a of the chuck jaw 3 when the workpiece is not held is prevented. It can prevent by the elasticity and friction which 32 has.
As a result, the fine chuck claw 3 can operate accurately.

The operating rod 2 of the present embodiment is a cylindrical pipe having a thickness that advances and retreats the hollow portion of the chuck holder 1, and includes a through hole 2a that is connected to the hollow portion at an intermediate portion thereof.
The operation rod 2 is supported so as to be able to advance and retreat in the center of the hollow portion of the chuck holder 1 and to be rotatable by attaching oil-free bushes 43 to both upper and lower ends.
The operating rod 2 includes a pressurizing portion 8 that presses the cam portion 9 of the chuck claw 3 at a tip portion thereof. The pressurizing unit 8 in this example supports the pressurizing ring 8a so that it can rotate and cannot be detached.

With these configurations, the chuck ring 5 of the chuck holder 1 and the pressurizing portion 8 of the operating rod 2 sandwich the base portions 3b of the plurality of chuck claws 3 related to the support groove 5c serving as the swing fulcrum, so that the chuck ring 5 A predetermined number of chuck claws 3 are respectively held under the same conditions.
The chuck claws 3 held in this way are moved to the base portions 3b of the chuck claws 3 as the operating rod 2 moves back and forth, so that the tip ends of the chuck claws 3 held by the chuck ring 5 are shifted. The opening of (working part 3a) changes.
Further, since the surface of the pressurizing portion 8 of the operating rod 2 moves following the curved surface of the surface of the cam portion 9, a stable opening amount that is free of rattling with respect to the chuck claw 3 can be obtained by rotating the operating rod 2. Can be given while responding.

  This embodiment can also be configured to produce the opposite action to the embodiment shown in FIGS. 18 to 20 as in the embodiment shown in FIG. That is, the operation rod 2 according to the embodiment may have a configuration in which a magnet core for attracting the cam portion 9 of the chuck claw 3 made of a magnetic material is provided at the tip portion instead of the pressurizing portion 8 (not shown). .

[About robot arm]
The robot arm according to the present embodiment rotatably supports the chuck holder 1 of the chuck on the bearing portion 17 of the arm housing 13 shown in FIG.

The bearing portion 17 includes a rotary bearing 17a that is in contact with the outer surface of the chuck holder 1, and the chuck holder 1 supported by the bearing portion 17 has a pulley 40 for receiving transmission of rotational force as an upper portion of the rotation transmitting means. As an integral part.
The rotation transmitting means refers to a member or a combination of members that transmits a force used for rotating the chuck to the chuck.

  The bearing portion 17 of the arm housing 13 includes a ring-shaped protruding portion 23 having a narrow inner diameter at an inner wall intermediate portion of a shaft hole penetrating vertically, and a ring-shaped storage portion 35 having a larger inner diameter at both ends of the inner wall. Are provided, and a cutout portion 36 is provided in a part of the protruding portion 23 to form an opening portion that continues to the air path 37.

  The rotary bearings 17a are mounted on the upper and lower sides of the projecting portion 23 in the shaft hole, and O-rings 38 having elasticity and airtightness are mounted on the surrounding storage portions 35. Subsequently, the chuck is loaded from the bottom of the arm housing 13 into the bearing portion 17, and the washer 39 covering them is mounted on the rotary bearing 17 a and the O-ring 38 mounted on the protruding portion 23, and the pulley 40 is fixed to the pipe portion 1a of the chuck holder 1 so as not to be rotated and displaced while closely contacting the upper surface of the washer 39. As described above, the chuck is rotatably supported by the bearing portion 17 (see FIGS. 18B, 19A, and 20).

  The robot arm includes an elevating means for moving the operation rod 2 back and forth in the arm housing 13. As in the above-described embodiment, the elevating means is configured by connecting the piston rod 14a of the cylinder mechanism 14 that advances and retracts in parallel with each other and the operation rod 2 of the chuck by the transmission arm 15. Even in the configuration of the electric arm 15, the electric arm 15 similar to the embodiment described above can be employed.

  Similar to the previous embodiment, the arm housing 13 is provided with a timing belt 21 as a rotation transmission means for rotating the chuck holder 1 of the chuck, and an air path 37 following the notch portion 36 of the bearing portion 17. Is provided.

The air path 37 starts from the notch 36 of the bearing portion 17 and has a ventilation groove 44 provided on the side surface of the arm housing 13 along the longitudinal direction thereof, and a lead hole that connects the inside of the ventilation groove 44 and the notch 36. 45.
The ventilation groove 44 forms a part of the air path 37 by sealing the side thereof with a sealing tape 44a. A lead-in hole 46 is provided from the end of the ventilation groove 44 to the lead-out opening 47 that opens on the upper surface of the arm housing 13, and an air tube connection portion is provided with the draw-out opening 47 as the end of the air path 37 (not shown).

  The robot arm of the present embodiment is configured as described above, so that the suction nozzle connected to the hollow portion at the distal end portion of the operation rod 2 (see, for example, FIG. 5 or FIG. 11), as in the previous embodiment. By attaching 12 and making the hollow part have a sufficient negative pressure, it can be used as an adsorbing means for adsorbing and holding an object to be held by the chuck or supplementing the holding force.

  In the present embodiment, the method of setting the negative pressure in the hollow portion is different from the method of sucking air from the upper end of the operation rod 2 through the air tube or the like as in the previous embodiment, and the side surface of the operation rod 2 and the chuck holder 1. The upper and lower oil-free bushes 43 and 43 and the upper and lower O-rings 38 and 38 are mounted on the gap 41 sandwiched between the inner surfaces of the chuck holder 1 and the gap 42 sandwiched between the outer surface of the chuck holder 1 and the inner surface of the bearing portion 17, respectively. In addition, the airtightness of both the gaps 41 and 42 is ensured.

  With this configuration, the air intake path communicates with the hollow portion of the operating rod 2 and the gaps 41 and 42 through the through holes 2a and 1f, and communicates with the air path 37 through the notch portion 36 of the bearing portion 17, An air tube or the like is connected to a connection portion attached to the housing 13.

  With the above configuration, the hollow portion of the operating rod 2 can be set to a sufficient negative pressure without connecting the air tube to the chuck. Thereby, it can be used as an adsorbing means for adsorbing and holding an object to be held on the chuck or supplementing the holding force.

  In addition, as a result of eliminating the need for air tube piping to the operating rod 2, the operating rod 2 and the chuck claw 3 are rotated in the same direction, and the frictional force in the rotational direction between the operating rod 2 and the pressure ring. Can be eliminated. As a result, it is not always necessary to use a bearing for the pressure ring 8 a, and the pressure ring 8 a having a shape suitable for the cam portion 9 of the chuck claw 3 can be adopted.

1 chuck holder,
1a pipe part, 1b holder part, 1c collar part,
1d block, 1e fixing hole, 1f through hole,
2 Operation rod, 2a Through hole,
3 chuck claw, 3a working part, 3b base part, 3c protrusion,
4 chuck,
5 chuck ring,
5a upper chuck ring, 5b lower chuck ring, 5c support groove,
6 workpieces, 7 notches,
8 Pressure part, 8a Pressure ring, 8b Cap,
9 cam part, 10 support groove, 11 fulcrum ring, 12 suction nozzle,
13 arm housing,
14 cylinder mechanism, 14a piston rod, 14b cylinder chamber,
15 transmission arm, 15a leaf spring, 15b support hole, 16 load adjusting member,
17 bearing part, 17a rotary bearing,
18 pulley, 18a lock ring, 19 cylinder link,
20 spacer,
21 timing belt,
22 magnet core, 23 projecting part, 24 bush, 25 nut,
26 fiber sensor, 26a lens, 27 operation rod,
28 Hall element, 28a Magnet grain, 29 Circuit board, 30 Presser plate,
31 cable, 32 rattling, 33 receiving hole, 34 mounting screw,
35 storage part, 36 notch part, 37 air path,
38 O-ring, 39 washer, 40 pulley,
41 gap (side of operation rod), 42 gap (side of chuck holder),
43 Bush,
44 ventilation groove, 44a sealing tape,
45 outlet holes, 46 inlet holes, 47 outlets,

Claims (15)

It consists of a chuck holder (1), an operating rod (2), and a chuck claw (3).
The chuck holder (1) supports a notch (7) in which the chuck claw (3) can swing freely so as to satisfy the function of holding and releasing the workpiece (6), and the back surface of the base (3b) of the chuck claw (3). It has a swing fulcrum,
The operating rod (2) is provided with a pressurizing part (8) or a magnet core (22) protruding laterally at a tip part thereof,
The operation rod (2) is inserted into the hollow part of the chuck holder (1) so as to be able to advance and retract,
The base portion (3b) of the plurality of chuck claws (3) is clamped between the pressurizing portion (8) of the operating rod or the swing fulcrum of the magnet core (22) and the chuck holder (1),
On the inner surface of the base portion (3b) of each chuck claw (3), the amount of advancement / retraction of the pressurizing portion (8) or the magnet core (22) accompanying the advancement / retraction of the operating rod (2) is determined by the centrifuge of each chuck claw (3). A chuck provided with a cam portion (9) that converts the amount of oscillation in the centripetal direction. The chuck holder (1) is provided with notches (7) in which the base (3b) of the chuck claw (3) is swingably accommodated at one or more desired angular intervals along the longitudinal direction of the chuck holder (1),
The outer surface of the chuck holder (1) is provided with a support groove (10) that crosses the notch (7) and goes around the chuck holder (1), and the support groove (10) has a swing fulcrum of the chuck claw (3). The chuck according to claim 1, wherein a fulcrum ring (11) is loaded.   At the bottom of the chuck holder (1), a fulcrum ring (3b) of the chuck claw (3) that fits in the notch (7) of the chuck holder (1) and a fulcrum ring (10) loaded in the support groove (10) of the chuck holder (1) ( The chuck according to claim 2, further comprising a chuck ring (5) covering 11). A chuck ring (5) covering the side of the chuck holder (1) is provided,
The chuck claws (3) are provided with protrusions (3c) fitted on the swing fulcrum on the back surface of the base (3b),
The chuck ring (5) is composed of a pair of upper and lower rings (5a, 5b), and chamfered at the same depth to the lower end of the upper chuck ring (5a) and the upper end of the lower chuck ring (5b). And the chuck rings (5a, 5b) are in close contact with each other to form a swing fulcrum where the projections (3c) of the chuck claws (3) are accommodated, and the upper and lower rings (5a, 5b) are mutually connected. The base part (3b) of the chuck claw (3) which is fixed to the chuck holder (1) and is fixed to the chuck holder (1) and fits in the notch (7) of the chuck holder (1) is supported from the outside. Chuck.   An accommodation hole (33) is provided in the base (3b) of the chuck claw (3), and the accommodation hole (33) has an elastic rattle that has a thickness equal to or greater than the width of the notch (7) of the chuck holder (1) ( The chuck according to any one of claims 1 to 4, wherein 32) is loaded.   The chuck according to any one of claims 1 to 5, wherein the operation rod (2) is a hollow member and includes a suction nozzle (12) connected to the hollow portion at a tip portion thereof.   The chuck according to any one of claims 1 to 5, wherein the operating rod (2) is a hollow member, and the head of the sensor (26) is fixed to the tip of the operating rod (2).   The chuck according to any one of claims 1 to 7, wherein the operating rod (2) is rotatably supported with respect to the chuck holder (1).   Lifting means for rotatably supporting the chuck holder (1) of the chuck according to claim 8 on the arm casing (13) and moving the operating rod (2) back and forth on the arm casing (13), A robot arm provided with a rotation transmitting means for rotating the chuck holder (1). A chuck holder (1) of the chuck according to claim 6 is rotatably supported on an arm housing (13),
The bearing portion (17) supporting the chuck holder (1) is provided with means for ensuring the airtightness of the outer space (42) between the chuck holder (1) and the bearing portion (17). Means for ensuring airtightness of the inner space (41) between the rod (2) and the chuck holder (1);
The operation rod (2) is a hollow member and includes a through hole (2a) for communicating the hollow portion with the inner space (41). The chuck holder (1) has an inner space (41) and an outer space ( 42) is provided with a through hole (1f) for communicating, and an air path (37) for communicating the outer gap (42) and the outlet (47) of the arm casing (13) with the arm casing (13), and an operation A robot arm comprising lifting and lowering means for moving the rod (2) back and forth, and rotation transmission means for turning the chuck holder (1).   The said raising / lowering means connects the piston rod (14a) of the cylinder mechanism (14) which advances and retracts substantially parallel, and the operation rod (2) of a chuck | zipper by the transmission arm (15). The robot arm according to any one of the above. The elevating means includes two or three cylinder mechanisms (14) in which each piston rod (14a) advances and retreats in parallel and connects each piston rod (14a), and operates with all cylinder mechanisms (14). 12. The robot arm according to claim 11, wherein the rods (2) are arranged side by side in a substantially straight line, and the operation rods (2) are arranged at their ends. The robot arm according to any one of claims 11 and 12, wherein the cylinder mechanism (14) is housed in an arm housing (13). The robot arm according to any one of claims 11 to 13, wherein the transmission arm (15) is a plurality of leaf springs (15a) overlapped with an interval in an advancing and retreating direction of the operating rod (2). 15. The robot arm according to claim 14, further comprising a load adjusting member (16) for connecting and supporting the plurality of leaf springs (15a) so as to be position-adjustable in a part of the longitudinal direction.