JPH077113Y2 - Gripping device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a gripping device, which is provided in, for example, a robot hand and grips a work (workpiece).

[Prior Art] As a gripping device of this type, a cable having a hinge joint is provided with a cable, and the pulling operation of the cable closes the finger to grip the work or open the finger. It is known to release the grip of the work.

[Problems to be Solved by the Invention] By the way, in the above-mentioned gripping device, it is necessary to mount the cable both inside and outside the finger. Moreover, it is necessary to separately provide a pulley and a hose for guiding the cable. Therefore, the number of parts increases and the structure becomes complicated.

Further, in order to open and close the finger as described above, at the same time as tensioning or loosening the inner cable,
The outer cable needs to be relaxed or taut. Therefore, when pulling the cable with the motor,
It becomes difficult to control the motor.

In this regard, conventionally, there is known a structure in which a plurality of arms are hinge-supported, air is supplied to a bellows-shaped actuator set at each hinge portion, and each arm is pivotally operated to grip a work. (For example, Japanese Patent Publication Sho 57
-39911 gazette).

Further, as another gripping device, a plurality of fingers are hingedly supported, and air is supplied to a piston type actuator set on a finger on the base end side of each hinge portion, and a finger on the tip end side is connected to a piston tip end portion of the actuator. A structure is known in which a work is grasped by pressing and rotating the work (see, for example, Japanese Utility Model Publication No. 49-31332).

According to each of the above configurations, since air is supplied to the actuator to drive the arm and finger, the structure and drive control are easier than the cable type.

However, since the former bellows-shaped actuator itself has a structure that expands and contracts, it is possible to grip a workpiece with a soft touch. It has a short life due to excessive stress.

On the other hand, the latter piston type actuator has a structure in which the finger is directly pressed by the tip of the piston to rotate.
Since the finger is always firmly pressed and held by sliding friction with the piston tip portion, it is difficult to obtain flexible rotation,
It is difficult to grip the work piece by soft touch, which may damage the work piece.

[Purpose of device]

This invention was made to solve the above problems,
An object of the present invention is to provide a gripping device that has a long life and can appropriately grip a work without fear of damage.

[Means for Solving the Problems]

In the gripping device according to the present invention, a finger device for gripping a work is provided with a first cylinder fixed to the main body of the device and a second cylinder rotatably supported by a tip end portion of the first cylinder via a hinge. A cylinder, a first piston slidable in the first cylinder, and a first piston in the first cylinder.
A first air chamber formed on the base end side of the piston, a second piston slidable on the second cylinder, and a tip end side of the second piston in the second cylinder. A second air chamber, a flexible connecting member connected to the first cylinder and the second piston, and an air passage communicating with the first and second air chambers. It is characterized by

[Action]

In the above configuration, when air is supplied to the first air chamber,
The air is supplied to the second air chamber through the air passage of the connecting member, and the first and second pistons and the first and second pistons are supplied.
Both air chambers expand due to relative movement between the two air chambers.

On the other hand, the first and second pistons are connected and held to each other by a connecting member at predetermined intervals, and the first cylinder and the second cylinder are rotatably hinged to each other.

Therefore, the expansion of both air chambers causes the second cylinder to rotate with respect to the first cylinder via the hinge,
The work can be gripped. At this time, the connecting member follows the rotation of the second cylinder and, due to its flexibility, is curved in a gentle curvature in the longitudinal direction, so that the smooth rotation of the second cylinder can be achieved. it can.

At the time of this rotation, since the second cylinder is held by the flexible connecting member and can be flexibly rotated, there is no risk of damaging the work by grasping the work with a soft touch.

Further, the connecting member follows the rotation of the second cylinder and bends in a gentle curvature in the longitudinal direction. Since the connecting member is not a structure that expands and contracts by itself, strength fatigue and unreasonable bending portion stress are caused. No generation and long life.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a first embodiment of the present invention,
In the figure, the gripping device includes two rows of finger devices 2A and 2B fixed to the device body 1, a three-way valve 4 connected to the air port 3 of each finger device 2A and 2B, and a positive pressure pump 5. There is. 6
Is a gripping rod for gripping the work W, which is individually attached to the finger devices 2A and 2B in each row.

As shown in FIG. 2, the finger devices 2A and 2B in each row have a bilaterally symmetrical structure. These finger devices 2A and 2B include a first cylinder 11, a second cylinder 12, a hinge 25, first and second pistons 14 and 15, a connecting member 16 and the like.

A base end portion 11a of the first cylinder 11 is fixed to the apparatus main body 1 with a bolt (not shown). A tip portion 11b of the first cylinder 11 is open, and a first piston 14 is slidably inserted from the tip portion 11b side. A first air chamber 21 is formed at the base end side C of the first piston 14 in the first cylinder 11. The first air chamber 21 communicates with the first air passage 31 through the air port 3 formed in the side wall of the first cylinder 11, and is formed in the first piston 14 at a first position. It communicates with the second air passage 32.

A second cylinder 12 is rotatably supported in a direction indicated by an arrow A on the inner side E of the tip portion 11b of the first cylinder 11 via a hinge 25. This second cylinder 12
Has a base end portion 12a opened, and a second piston 15 is slidably inserted from the base end portion 12a side. Second above
A second air chamber 22 is formed on the tip side D of the second piston 15 in the cylinder 12.

The first piston 14 and the second piston 15 are connected to each other by a flexible connecting member 16. A third air passage 33 is formed in the connecting member 16, and the third air passage 33 communicates with the second air passage 32 in the first piston 14 and also has the third air passage 33. It communicates with the second air chamber 22 through a fourth air passage 34 formed in the second piston 15. In addition, the connecting member
Reference numeral 16 denotes a flexible tube such as rubber, and as shown in FIG. 3, the second cylinder 12 has a hinge 25 as an axis and an arrow A.
When the second cylinder 12 is rotated in the direction indicated by, it can be bent in the rotation direction of the second cylinder 12 and does not buckle due to the expansion force of the first and second air chambers 21 and 22. Has strength. Further, the connecting member 16 and the pistons 14, 15 may be bonded to each other using an adhesive, or,
It may be integrally molded by insert molding or the like. In addition, 17 is an air seal attached to the pistons 14 and 15, 18 is a bolt hole, and 27 is a return spring attached to the hinge 25.

On the other hand, as shown in FIG. 4, the air port 3 that connects the first air chamber 21 and the first air passage 31 has the finger devices 2A, 2B.
Of which only one pair of finger devices facing each other are formed,
Not formed on the other two sets of finger devices, instead,
An air communication path 35 communicating with the first air chamber 21 in each of the pair of finger devices is formed in each of the two sets of finger devices. Incidentally, 36 is a plug and 37 is a seal ring.

Next, the operation of the above configuration will be described.

First, when the finger devices 2A and 2B in FIG. 1 are driven to grip the work W, as shown in FIG. 3, the port a of the three-way valve 4 in FIG. 2 is opened to the atmosphere. By rotating the three-way valve 4, the port c of the three-way valve 4 is communicated with the positive pressure pump 5, the port b is opposed to the closing portion 51, and the port a is communicated with the first air passage 31. As a result, the compressed air from the pump 5 is sent into the first air chamber 21 through the air port 3. At this time, the air communication path 35 shown in FIG.
Thus, the air is sent into the first air chamber 21 of each finger device 2A, 2B. Further, the air is supplied to the first air chamber 21.
To the second, third and fourth air passages 32, 3 in FIG.
It is also fed into the second air chamber 22 through 3,34. As a result, both air chambers 21 and 22 expand, while both cylinders 11 and 22 expand.
Since the 12 are rotatably connected to each other by the hinge 25,
The second cylinder 12 rotates about the axis of the hinge 25 in the direction indicated by arrow A. When the second cylinder 12 rotates, the connecting member 16 can bend in the rotation direction A of the second cylinder 12, so that the second cylinder 12 rotates about the axis of the hinge 25. I can't prevent you from doing it. Therefore, the work can be gripped by each gripping rod 6.

Next, in releasing the gripping of the work, the three-way valve 4 is rotated as shown in FIG. 2 from the state of FIG. 3 in which the port c of the three-way valve 4 communicates with the pump 5. , The port a of the three-way valve 4 is opened to the atmosphere. As a result, the supply of air to the first air chamber 21 is stopped, the second cylinder 12 returns to its original position by the return spring 27, and the gripping of the work can be released.

As apparent from the above, when air is supplied to the first air chamber 21, the air is supplied to the second air chamber 22 through the air passage 33 of the connecting member 16, and the first and second pistons 1
Both air chambers 21 and 22 are expanded by the relative movement between 4, 15 and the first and second cylinders 11, 12.

On the other hand, the first and second pistons 14 and 15 are connected and held by a connecting member 16 at regular intervals, and the first cylinder 11 and the second cylinder 12 are rotatably hinged to each other.
Supported by 25.

Therefore, due to the expansion of the air chambers 21 and 22, the second cylinder 12 is rotated with respect to the first cylinder 11 via the hinge 25, and the work W can be gripped. At this time, the connecting member 16 follows the rotation of the second cylinder 12, and due to its flexibility, is curved in a gentle curvature in the longitudinal direction as shown in FIG. It is possible to achieve smooth rotation of the.

At the time of this rotation, the second cylinder 12 is held by the flexible connecting member 16 and can be flexibly rotated. Therefore, the work W may be grasped by a soft touch and damaged. Absent.

Further, the connecting member 16 follows the rotation of the second cylinder 12 and is curved in a gentle curvature in the longitudinal direction,
Since the structure itself does not expand and contract, it does not generate strength fatigue or excessive local stress and has a long life.

FIG. 5 is a sectional view showing a second embodiment of the present invention.
In this embodiment, the number of cylinders is increased to three, and these three cylinders 11, 12, 13 are linearly connected via two hinges 25, 26. Here, the second cylinder 12 at the center is opened to the base end side C and the front end side D,
The second piston 15 is slidably inserted from the base end side C, and the third piston 19 is slidably inserted from the tip end side D. Second
The air chamber 22 and the third air passage 23 communicate with the third air chamber 23 through the fifth to seventh air passages 35, 36, 37. In addition, 20 is a 4th piston. By increasing the number of cylinders 11, 12, 13 in this way, the same effect as in the above-described embodiment can be obtained, and the turning angle of the grip bar 6 mounted on the third cylinder 13 can be made larger, resulting in a large size. It is possible to adapt to gripping works with different heights. Other configurations are the same as those in FIG. 2, and the corresponding parts are denoted by the same reference numerals and detailed description thereof is omitted.

In the above embodiment, three finger devices 2A and 2B in two rows are provided, but it goes without saying that other numbers may be used.

[Effect of device]

As described above in detail, according to the present invention, the first and second cylinders are rotatably supported via hinges, and the first and second pistons are slidably fitted in the respective cylinders. And connecting the pistons with a flexible connecting member, forming an air passage communicating with the first and second air chambers in the connecting member, and supplying the air passages to the first and second air chambers. By expanding the air chambers with the relative movement between the pistons and the cylinders,
The second cylinder is rotated with respect to the first cylinder via a hinge, and at the time of this rotation, the second cylinder is held by a flexible connecting member so that flexible rotation can be obtained. Therefore, there is no risk of damaging the work by gripping the work with a soft touch.

In addition, since the connecting member follows the rotation of the second cylinder and bends in a gentle curvature in the longitudinal direction, and does not expand or contract itself, strength fatigue and excessive local stress are generated. And has a long life.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an example of a gripping device according to the present invention, FIG. 2 is a sectional view showing a main part of the gripping device, and FIG.
The figure is a sectional view of an essential part for explaining the operation of the gripping device,
FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2, and FIG. 5 is a sectional view of the essential parts showing another example of the gripping device according to the present invention. 1 ... Device body, 2A, 2B ... Finger device, 11 ... First cylinder, 11a ... Base end, 11b ... Tip part, 12 ... Second cylinder, 14 ... First piston , 15 ... second piston, 16 ... connecting member, 21 ... first air chamber, 22 ... second
Air chamber, 25 ... Hinge, 33 ... Air passage, C ... Base side, D ... Tip side, W ... Work.

Claims (1)

[Scope of utility model registration request] 1. A gripping device for driving a finger device to grip a work, wherein the finger device is a first device fixed to a device body.
Cylinder, a second cylinder rotatably supported by a tip end portion of the first cylinder via a hinge, a first piston slidable on the first cylinder, and the first cylinder.
A first air chamber formed on the base end side of the first piston in the second cylinder, a second piston slidable in the second cylinder, and a second piston in the second cylinder.
A second air chamber formed at the tip end side of the piston, a flexible connecting member connected to the first cylinder and the second piston, and the first and second air chambers. An air passage communicating with each other, and the air supplied to the first and second air chambers expands the air chambers by relative movement between the pistons and the cylinders to expand the second air chambers. A gripping device characterized in that the cylinder is configured to rotate with respect to the first cylinder.