JP2000127077A - Block holding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device installed at the tip of an arm of a manipulator to hold a block, which is capable of correctly holding a heavy concrete block without slippage. SOLUTION: This holding device is so constructed that suspended base shafts 11a, 11b are provided with sliders 12a, 12b, expansible horizontal shafts 13, 13 are fitted to both sides of the slider 12, the tips are provided with contact parts 14, 14, a rubber plate or the like is used in the pressing surface 16 of the contact part 14, and the lower end of the base shaft and the tip of the horizontal shaft or the contact part are connected to each other by a support rod 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gripping device mounted on the tip of an arm of a manipulator, and more particularly to a device capable of gripping a heavy block safely without falling. Here, the block is interpreted in a broad sense without being limited to the concrete block constituting the fence, and means a box-shaped three-dimensional object.

[0002]

2. Description of the Related Art One of the severe tasks in which young labor tends to be short in recent years is the work of masonry of blocks constituting a fence.
Elderly people who are physically inferior to young people are often engaged in work, and the physical burden is large. Therefore, it would be very meaningful if such an operation could be performed in block building using a robot manipulator.

In order to assemble blocks using a manipulator, first, a gripping device capable of safely lifting a heavy block is required. However, there is no chuck part when gripping the block, it must be lifted by the frictional force generated by pinching the block surface, and if it is a concrete block such as a fence, it is very heavy and there is a risk of sliding down There is. If it slips and shifts even if it does not fall, it will not be possible to stack correctly.

[0004]

As described above, when performing the work of assembling the blocks constituting the fence by the manipulator, the above-described problems are encountered in the block gripping device. The problem to be solved by the present invention is this problem, and to provide a gripping device that can correctly grip without slipping in order to sequentially stack predetermined blocks.

[0005]

The gripping device of the present invention is mounted on the end of an arm of a manipulator to grip a box-shaped block, and has a structure capable of generating a large frictional force. Here, the block to be gripped has a through hole, or at least a hole with an open upper portion, and has a form in which the gripping device can enter and grip the hole. Therefore, the outer shape is not particularly limited.

The gripping device has a base shaft extending vertically downward,
A slider is attached to the base shaft, and the slider has a horizontal axis extending to both sides. The horizontal axis is an extensible shaft, has a contact portion at the tip, and a contact surface of the contact portion is made of a material having a high friction coefficient such as a rubber plate. The distal end of the expanding and contracting horizontal shaft and the lower end of the base shaft are connected by a support bar, and the base shaft, the horizontal shaft, and the support bar form a right-angled triangle. The length of the support bar does not change.

By the way, as the length of the horizontal axis increases, the contact portions move outward and press against the inner wall surface of the hole of the block. If the base shaft rises in this state, the block is lifted by the hitting portion, and if the horizontal axis is contracted when it is moved to a predetermined position, the contact surface of the hitting portion is released from the inner wall surface of the hole and the block is released. Since the holding device is provided with the support rod, even a heavy block can be lifted without bending the horizontal axis.

If there are two holes in the center of the block, the above-mentioned gripping devices may be provided in pairs, and a structure in which the distance between the two gripping devices can be adjusted is possible. Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.

[0009]

FIG. 1 shows an embodiment showing a movable manipulator, which comprises a carriage 1, which is a moving device, an arm 2, a gripping device 3, and a camera 4. The cart 1 has wheels 5, 5 ...
Is mounted and can be moved by a motor mounted thereon, and the motor controls the moving distance of the bogie by controlling the number of rotations. The wheels are equipped with rubber tires that can roll directly on the ground.

[0010] The manipulator is constructed so that blocks can be stacked while correcting the positional deviation at that time by moving the bogie directly on the ground. The arm 2 is formed by connecting a plurality of links 6a, 6b,..., And the arm 2 can be directed in an arbitrary direction by bending the individual links 6a, 6b,. The arm 2 is mounted on a cart 1, and a gripping device 3 of the present invention is attached to a tip thereof.

FIG. 2 is a specific example showing a gripping device and a block of the present invention. This block 7 is made of box-shaped concrete, and has two holes 8a and 8b penetrating in the center. The cross section of the holes 8a and 8b is rectangular,
It has inner wall surfaces 9a and 9b parallel to each other. The holding devices 3a and 3b shown in FIG.
b and can be lifted. Concrete blocks are very heavy and have a structure that will not slide down when gripped.

FIG. 3 is a detailed view of the gripping device, in which gripping devices 3a and 3b are mounted in pairs. The base 10 is attached to the tip of the arm and has two base shafts 11a and 11b that are suspended from the base 10 and branched.
Sliders 12a and 12b are movably attached to a and 11b. The slider 12 has horizontal shafts 13, 13 that extend and contract horizontally extending to both sides, and hitting portions 14, 14 are attached to the ends of the horizontal shafts.

When the horizontal shaft 13 is extended, the hitting portions 14 protrude outward to increase the distance between the hitting portions 14 and 14, and conversely, when the horizontal axis is reduced, the hitting portions 14 and 14 are reduced.
The distance between them becomes smaller. Here, the expansion / contraction means of the horizontal shaft 13 is not particularly limited, and a hydraulic cylinder is generally used,
Alternatively, a rack-pinion mechanism can be adopted. When a rack-pinion mechanism is employed, a torque motor is used, and the contact portion 14 is formed on the inner wall surface 9a of the block hole 8,
9b, the motor stops when the torque increases, and a spring is interposed at an appropriate position on the horizontal axis to prevent the torque motor from overloading and to prevent the contact pressure from relaxing. A support bar 15 is attached to the back of the contact portion 14, and the support bar 15 is connected to the lower end of the base shaft.

By the way, if the horizontal axis 13 extends,
Since there is no change in the length of the support rod 15, the slider 12
Falls, and conversely, when the horizontal axis 13 is shortened, the slider 12 rises. Therefore, the two horizontal shafts 13, 13 are shortened to enter the hole 8 of the block 7 with the distance between the contact portions 14, 14 reduced, that is, the arm 2 is moved to lower the gripping device 3 into the hole. The horizontal axis 13, 13 in the state
Is extended.

As a result, the hitting portions 14 and 14 move outward, and the hitting portions 14 and 14 correspond to the inner wall surfaces 9a and 9b of the hole 8.
Abut. The contact surface 16 of the contact portion 14 has an uneven surface and is made of a material having a high friction coefficient such as rubber. Accordingly, the horizontal shaft 13 is extended, and the contact surface 16 is pressed against the inner wall surface 9 of the hole 8 so that the block 7 can be lifted by the frictional force.

The gripping device 3 is formed symmetrically on both sides about a base shaft 11 as shown in FIG.
Even in the case where the holes 4 and 14 are pressed against the inner wall surfaces 9a and 9b of the holes, the pressing forces acting on the wall surfaces cancel each other, and the base shaft 11 is not bent. If the base 10 and the base shaft 11 are raised in this state, the block 7 is lifted, but the contact portions 14, 14 are supported by the support rods 15, 15 connected to the lower end of the base shaft 11, so that the block 7 is lifted.
Does not bend even if it is gripped. The gripping device shown in FIG. 3 has two base shafts 1 branched from a base 10.
1a and 11b are provided at the center, and each of the gripping devices 3a and 3b has two holes 8 formed in the block 7.
a and 8b, respectively, and clamp them.

In this embodiment, since two holes 8a and 8b penetrating through the block 7 are formed, two gripping devices are mounted so as to enter both holes. If the number of holes is one, the number of gripping devices may be one, and in a block having three holes, gripping is performed using three gripping devices or one gripping device that fits into a central hole. I can do it.

By the way, the manipulator stacks the blocks while moving. If a displacement occurs during the movement, the movement of the arm 2 is adjusted so that the blocks are stacked correctly. ing. Therefore, a camera 4 is attached to the tip of the arm 2 to determine whether or not the carriage 1 has moved correctly, and if the carriage 1 has shifted and moved, the arm 2 corrects the error.

FIG. 4 shows a case where the blocks 7a, 7b... Are assembled, and the blocks 7a to 7c are already correctly assembled. The block 7d is gripped by the gripping device 3, and the block 7d is correctly arranged. Is controlled as follows. FIG.
In FIG. 5, landmarks (X) are formed at predetermined positions on the upper surface of the block, and the blocks 7d are stacked based on the landmarks (X). The camera 4 attached to the tip of the arm projects the landmark (X), and the position of the carriage 1 after the carriage 1 has moved a certain distance is indicated by the camera 4.
Is determined based on the position of the landmark (X) projected on the image.

For example, the landmark (X) of the block 7b is projected to the correct position by the camera 4, and the blocks 7c are stacked, and the block 7d is a trolley based on the landmark (X) of the block 7c stacked immediately before. 1 is detected. That is, when the carriage 1 does not move correctly, the landmark (X) projected on the camera 4 is displaced, and the amount of this displacement is fed back to adjust the movement of the arm 2.

Here, the landmark is not limited to the X mark as shown in the figure, but the mark ○ is a mark having a shape that allows the position and direction deviation to be known because the direction deviation of the bogie is not known. It is necessary. Furthermore, X-shaped landmarks are not sufficient to know the vertical position shift and its inclination. The landmark (X) used as a reference for knowing the positional deviation of the cart 1 does not need to be the previous block, and the landmark described on the lower block to be stacked can be used. is there.

However, the present invention is not limited to various methods for detecting the displacement of the landmark (X) projected on the camera 4 and adjusting the movement of the arm 2 because there are various methods.
It is convenient to attach a camera to the tip of the arm because the height of the blocks to be stacked is gradually increased, but it is also possible to arrange the camera by providing another support portion that can adjust the height from the cart . Of course, the grasping device of the present invention is a device for grasping a block, and the movement and structure of the manipulator itself are arbitrary, and are not necessarily limited to the manipulator that moves.

As described above, in the block gripping device of the present invention, the slider is attached to the hanging base shaft, and a horizontal shaft is provided on both sides of the slider so as to be extendable and contractable. The contact portions are connected by support rods, and the following effects can be obtained.

[0024]

The block gripping device of the present invention is provided with a contact portion projecting on both sides around a hanging base shaft, which can be inserted into a hole of the block and held against an inner wall surface. Therefore, the large forces pressing against the inner wall surface are balanced and canceled, no bending moment acts on the base shaft, and the gripped block does not slide down or shift.

The hitting portion is supported by the support rod, and the horizontal shaft extending from the block is not bent and deformed, and the heavy block can be gripped safely and accurately. Therefore, if this gripping device is mounted on the end of the arm of the manipulator and work is performed, there is no need for the operator to hold and stack heavy blocks, and the work of assembling the blocks becomes very easy. The operator only has to work with the manipulator to pour concrete for connecting the blocks to be stacked.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a movable manipulator.

FIG. 2 shows a gripping device of the present invention and a block having two holes.

FIG. 3 shows a gripping device of the present invention.

FIG. 4 is a block assembly work;

[Explanation of symbols]

 Reference Signs List 1 cart 2 arm 3 gripping device 4 camera 5 wheel 6 link 7 block 8 hole 9 inner wall 10 base 11 base 12 slider 13 horizontal axis 14 hitting part 15 support rod 16 contact surface

Claims (2)

[Claims] 1. An apparatus for gripping a block by being attached to the end of an arm of a manipulator, wherein the block to be gripped has a hole in the center, and the gripping device has a slider on a hanging base shaft, and a slider on both sides of the slider. Attaches a horizontal shaft that can expand and contract, and has a contact portion at the tip, the contact surface of the contact portion is made of a material such as a rubber plate with a high friction coefficient, and supports the lower end of the base shaft and the tip of the horizontal shaft or the contact portion A block gripping device characterized by being connected by a rod. 2. The apparatus according to claim 1, wherein a hydraulic cylinder is used to extend and retract the horizontal shaft.