KR102038967B1 - Electrical elastic gripper - Google Patents

Abstract

According to the present invention, an electrical elastic gripper comprises a housing, a driving part coupled to a lower part of the housing, a gripper coupled to an upper part of the housing, and a power conversion part coupled to the driving part to convert a rotational motion by the driving part into a linear motion of the gripper. An elastic body is provided between the driving part and the power conversion part, and a rotational force by the driving part is transmitted to the power conversion part through the elastic body. Therefore, the present invention is capable of gripping a moving object or an object to be inspected with a desired force without damage.

Description

Electric elastic gripper

The present invention relates to a gripper for gripping an inspection or moving object, and more particularly, to an electro-elastic gripper capable of gripping a small inspection object with a constant gripping force without damage.

A gripper is a device that grips an object in order to move an object handled in a manufacturing field in which a manufacturing process is processed by an automated process to another process position or to perform a specific process.

The gripper market is closely related to the robot market, and the robot market for manufacturing is expected to maintain an annual average increase of more than 10%, following China and the United States, which has emerged as the world's No. 1 manufacturing robot sales country. Korea also expects the production and demand of robots to expand.

In particular, the use of grippers in factory automation is very extensive, and the number of grippers developed accordingly is increasing. In addition, in the shipbuilding, aviation, electronics, semiconductors, as well as in the photovoltaic industry in recent years, the use of grippers suitable for the use is increasing.

Therefore, the bright prospect of the robot market is expected to bring active movement to the gripper market.

Such a gripper is provided at the front end of the robot arm, and is made of various types such as a fork forceps, a forklift type, a vacuum suction type, and used to gram or ungram an article by a hydraulic / pneumatic cylinder.

However, the gripper operated by the hydraulic / pneumatic cylinder is not only excessively expensive for the hydraulic / pneumatic cylinder itself, but it is difficult to be used for precision work because it is not precisely driven due to the operation structure of the hydraulic and pneumatic cylinder, and to perform precise work. Since various sensors must be provided inevitably, in a large-scale automation process, it becomes a factor to increase the unit cost.

In addition, in the case of a gripper for holding a small precision component that is very likely to be damaged, even a small increase in the holding force or a small error of the component is very likely to damage the component.

Therefore, it is necessary to develop a gripper that can reduce the cost of equipment efficiently and have precise control while providing price competitiveness.

Republic of Korea Patent Publication No. 10-2010-0053808

The present invention has been made in order to solve the above-mentioned problems of the prior art, to provide an electrically resilient gripper that can grip a moving or inspected object with a desired force without damage.

The objects of the present invention are not limited to the above-mentioned objects, and other objects that are not mentioned will be clearly understood by those skilled in the art from the following description.

The motor-driven elastic gripper of the present invention for achieving the above object is a housing, a drive unit coupled to the lower portion of the housing, a gripper coupled to the upper portion of the housing and the drive unit is coupled to the rotational movement by the drive unit is a linear It includes a power conversion unit for converting the movement, an elastic body is provided between the drive unit and the power conversion unit, the rotational force by the drive unit is configured to be transmitted to the power conversion unit through the elastic body.

In addition, the output shaft outer peripheral surface of the drive unit is coupled to the first power transmission unit for transmitting a driving force, the first power transmission unit is coupled to the elastic control unit, the elastic body is coupled to the elastic control unit.

The power converter includes a second power transmission unit coupled to the elastic body, a cam plate connected to the second power transmission unit and having a plurality of cam grooves, a cam shaft inserted into the cam groove and a gripper connected to the cam shaft. do.

In addition, the cam plate may be configured to rotate together with the second power transmission unit.

In addition, the elastic body may be combined with the elastic control unit and the second power transmission unit.

In addition, the outer circumferential surface of the first power transmission unit is formed in the radial direction, two stops are provided spaced apart by a predetermined interval along the circumferential direction, and the outer circumferential surface of the second power transmission unit along the axial direction of the drive output shaft It may be further provided with an anti-rotation part formed to protrude long and positioned between the stops.

In addition, the elastic body may be a torsion spring.

In addition, the cam shaft may be configured to move along the cam groove formed in the cam plate by the rotation of the cam plate.

In addition, the elastic control unit is fixed to the outer peripheral surface of the first power transmission portion, it may be configured to change the position through the rotation on the outer peripheral surface of the first power transmission portion.

In addition, the elastic force of the elastic body between the elastic control unit and the second power transmission unit is changed by the rotation of the elastic control unit.

The motor-driven elastic gripper of the present invention for solving the above problems has the following effects.

First, by transmitting the rotational force of the drive unit to the gripper by using an elastic body, it is possible to control the gripping pressure transmitted to the gripper very precisely even if the drive unit is not precisely controlled.

Second, the elastic force of the elastic body can be changed very easily, and even when the size and type of the gripping object are changed by changing the elastic force, it can be used without replacing the gripper.

Third, even if an error occurs in the driving amount of the driving unit, the amount of change in the gripping pressure of the gripper according to the change in the driving amount is very small, thereby preventing damage to the gripping object.

The effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a perspective view showing an electric elastic gripper according to the present invention
Figure 2 is an exploded perspective view showing the main components of the electric elastic gripper according to the present invention
Figure 3 is a perspective view showing the power transmission portion of the electric elastic gripper according to the present invention
4 is a sectional view showing a power transmission process of the electric elastic gripper according to the present invention.
5 is a perspective view showing a gripper operation process of the electric elastic gripper according to the present invention

Embodiments will be described with reference to the accompanying drawings. In the description of this embodiment, the same name and the same reference numerals are used for the same configuration and additional description thereof will be omitted.

In addition, in describing the embodiments of the present invention, the same name and the same reference numerals are used for the elements having the same function, and it is revealed that they are not substantially the same as in the related art.

In addition, the terms used in the embodiments of the present invention are merely used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise.

In addition, in the embodiments of the present invention, the terms "comprise" or "have" are intended to designate that there exists a feature, number, step, operation, component, part, or a combination thereof described in the specification. Or other features or numbers, steps, operations, components, parts or combinations thereof in any way should not be excluded in advance.

Hereinafter, the electric elastic gripper according to the present invention will be described in detail with reference to FIGS. 1 to 5.

1 is a perspective view showing a motor-driven elastic gripper according to the present invention, Figure 2 is an exploded view showing a motor-driven elastic gripper according to the present invention.

As shown in FIG. 1, the electric elastic gripper according to the present invention includes a housing 10, a driving unit 100 coupled to a lower portion of the housing 10, and a power transmission unit provided in the housing 10. 200, a power converter 300 connected to the power transmission unit 200 and a gripper 500 connected to the power converter 300 and coupled to an upper portion of the housing 10.

The electric elastic gripper according to the present invention has a structure in which two grippers 500 located on the upper portion of the housing 10 move in a direction approaching or away from each other, and grips an object located between the grippers 500.

Looking at the operation principle of the gripper 500, first, when the output shaft 110 of the drive unit 100 is rotated, the rotational force of the output shaft 110 through the power transmission unit 200 the power conversion unit ( 300, the power converter 300 converts the rotational motion of the output shaft 110 into a linear motion of the gripper 500 so that the gripper 500 grips an object.

As shown in FIG. 1, the housing 10 according to the present invention includes a lower housing 12 to which the driving unit 100 is coupled, and an upper housing coupled to an upper portion of the lower housing 12 and to which a gripper 500 is coupled. (11).

The driving unit 100 is configured to rotate the output shaft 110 at a predetermined angle forward or reverse according to a signal from a controller (not shown). Preferably, the driving unit 100 may be formed of a step motor.

The output shaft 110 is provided with a first power transmission unit 210 is fixedly coupled to the output shaft 110 to rotate with the output shaft 110. The first power transmission unit 210 is formed in a cylindrical shape, and includes a first stop portion 211 and a second stop portion 212 protruding in a radial direction.

The first stop portion 211 and the second stop portion 212 are spaced apart in the circumferential direction with the rotation preventing portion 241 of the second power transmission unit 240 to be described later, a specific coupling method And the power transmission method looks at the configuration of the second power transmission unit 240 to be described later.

An elastic control unit 220 is coupled to the outer circumferential surface of the first power transmission unit 210. The elastic control unit 220 is configured in a ring shape, it is configured to change the position by rotating relative to the first power transmission unit 210.

In addition, a plurality of screw holes are formed in a radial direction on an outer circumferential surface of the elastic adjusting unit 220, and the elastic adjusting unit 220 is connected to the first power transmission unit 210 by fastening screws through the screw holes. It is configured to be fixed.

Meanwhile, the elastic body 230 is coupled to the elastic control unit 220, and the second power transmission unit 240 is coupled to the elastic body 230.

Preferably, the elastic body 230 may be a torsion spring having protrusions formed on the bottom and the top, respectively. In this case, the lower protrusion of the torsion spring may be coupled to the elastic control unit 220, and the upper protrusion of the torsion spring may be coupled to the second power transmission unit 240.

3 illustrates an exploded view and an assembly view of the first power transmission unit 210, the elastic control unit 220, the elastic body 230, and the second power transmission unit 240.

As shown in FIG. 3, the second power transmission unit 240 has a hollow cylindrical shape, and a lower portion of the second power transmission unit 240 protrudes downward along the axial direction of the output shaft 110. The portion 241 may be formed. In addition, the anti-rotation part 241 may be configured to be positioned between the first stop part 211 and the second stop part 212 of the first power transmission part 210.

Hereinafter, the process of transmitting the rotational force of the output shaft 110 to the second power transmission unit 240 will be described with reference to FIG. 4.

As shown in Figure 4 (a), the first power transmission unit 210, the elastic control unit 220, the elastic body 230 and the second power transmission unit 240 are sequentially coupled, the first The second stopper 212 between the first stopper 211 and the second stopper 212 of the first power transmission part 210 may be rotated by the second power transmission part 240. Combined in contact with

Then, when the output shaft 110 is rotated in the clockwise direction on the drawing, as shown in Figure 4 (b), the first power transmission unit 210 rotates with the output shaft 110. Since the force necessary for the movement of the gripper 500 is very small before the object is gripped by the gripper 500, the second power transmission part 240 may be formed by the elastic force of the elastic body 230. Rotate substantially the same as 210.

Since the force required for the movement of the gripper 500 is increased when the object is gripped between the gripper 500, a larger force is applied to the elastic body 230, and as shown in Figure 4 (c), The rotation amount of the second power transmission unit 240 is smaller than the rotation amount of the first power transmission unit 210. That is, the rotation preventing part 241 and the second stop part 212 are spaced apart from each other along the circumferential direction. Then, when the gripping force of the object between the gripper 500 is gradually increased, the gripper 500 is substantially not moved and only the gripping force is increased. In this case, even if the first power transmission unit 210 rotates, the first power Only the elastic force of the elastic body 230 positioned between the transmission unit 210 and the second power transmission unit 240 increases, and the second power transmission unit 240 no longer rotates.

Thereafter, when the first power transmission unit 210 further rotates to increase the holding power, as shown in FIG. 4 (d), the first stop portion 211 and the second of the first power transmission unit 210 are used. The rotation preventing unit 241 of the power transmission unit 240 is in contact.

The first power transmission unit 210 further rotates while the first stop portion 211 of the first power transmission unit 210 and the rotation preventing unit 241 of the second power transmission unit 240 are in contact with each other. In this case, since the rotational force of the first power transmission unit 210 is directly transmitted to the second power transmission unit 240 in contact with the first power transmission unit 210, instead of the elastic force of the elastic body 230, The gripping force of the gripper 500 is rapidly increased.

Therefore, preferably the operating range of the electric elastic gripper according to the present invention is the first stop portion 211 of the first power transmission portion 210 and the rotation preventing portion 241 of the second power transmission portion 240 is It should be determined by the radius of rotation before contact with each other.

This can be controlled by adjusting the elastic force of the elastic body 230, which can be achieved by changing the position by rotating the elastic control unit 220 on the first power transmission unit 210 as described above.

As such, by transmitting the rotational movement of the output shaft 110 of the driving unit 100 to the gripper 500 by using the elastic force of the elastic body 230, there is an error in the size of the object held between the grippers 500, or Even when there is some error in the amount of rotation of the output shaft 110, the change in the magnitude of the load applied to the gripping object by the gripper 500 is very small, so that the gripping object is not damaged.

In addition, even when the size and type of the gripping object are changed, the gripping force of the gripper may be adjusted by adjusting the elastic force of the elastic body 230 through the elastic adjusting unit 220 without replacing the gripper.

Meanwhile, as described above with reference to FIG. 4 (d), when the first stop portion 211 contacts the rotation preventing portion 241 and transmits the rotational force of the driving unit 100 to the gripper 500, the gripper 500. The large gripping force is transmitted very rapidly to the gripping object, which may cause a problem of being destroyed or damaged. Therefore, the first stop portion 211 may be configured to cut off the power applied to the driving unit 100 through the control unit when the load increases on the driving unit 100 in contact with the anti-rotation unit 241.

Alternatively, the first stop part 211 and the anti-rotation part 241 may be added to the first stop part 211 and / or the anti-rotation part 241 by adding a sensing means such as a displacement sensor or a pressure sensor. When the controller approaches or contacts within a predetermined distance, the controller may be configured to block the power applied to the driver 100.

On the other hand, it will be apparent to those skilled in the art that the first stop portion 211 and the second stop portion 212 may change their roles depending on the rotation direction of the output shaft 110.

Hereinafter, the moving process of the gripper 500 will be described with reference to FIGS. 2 and 5.

2, the power converter 300 is coupled to the upper portion of the second power transmission unit 240. Specifically, the cam plate 310 having two cam grooves 311 and 312 is fixedly coupled to the upper portion of the second power transmission unit 240.

In this case, the cam plate 310 and the second power transmission unit 240 may be fastened by bolts, coupled using protrusion-grooves, or the two fastening structures may be used simultaneously.

The cam plate 310 is fixed to the second power transmission part 240 and is configured to rotate together with the second power transmission part 240.

One end of two cam shafts 320 is inserted into and coupled to the cam grooves 311 and 312, and the other ends of the two cam shafts 320 are coupled to the gripper 500. The gripper 500 may vary in shape and size in consideration of the size and shape of the object to be gripped.

On the other hand, a protrusion is formed in the lower portion of the gripper 500, a groove is formed in the upper portion of the upper housing 11 along the moving direction of the gripper 500, the protrusion is inserted into the groove of the upper housing 11 Can be movably coupled.

Referring to FIG. 5, the process of moving the gripper 500 will be described in detail. As shown in FIG. 5A, one end of the cam shaft 320 is formed in the cam grooves 311 and 312 of the cam plate 310. The other end of the cam shaft 320 is inserted into and coupled to the fastening hole of the gripper 500.

In this case, a bearing 330 is provided between the cam grooves 311 and 312 and the cam shaft 320 to facilitate movement.

Then, when the rotational force of the output shaft 110 is transmitted to the second power transmission unit 240 through the elastic body 230, the cam plate 310 coupled with the second power transmission unit 240 is the second It rotates with the power transmission unit 240.

As shown in FIG. 5 (b), when the cam plate 310 rotates, the positions of the cam grooves 311 and 312 are changed, and the cam shaft 320 is moved along the cam grooves 311 and 312. Will move. Since the gripper 500 is fixed to the camshaft 320, the gripper 500 moves in the direction in which the gripper 500 grips an object together with the camshaft 320.

Then, as shown in Figure 5 (c), when the output shaft 110 of the drive unit 100 is further rotated, the cam plate 310 does not rotate or rotates in a very small amount, the elastic body 230 Since the rotational force is transmitted, the gripper change amount of the gripper 500 is very small.

In conclusion, even if the rotation amount change amount of the driving unit 100 is large, the change amount of the gripping force is very small, and the gripper control of the gripper 500 is very easy, and the change amount of the gripping force is also very small due to an object error or a control error of the driving unit. Damage to the object can be prevented.

As described above, a preferred embodiment according to the present invention has been described, and the fact that the present invention can be embodied in other specific forms in addition to the above-described embodiments without departing from the spirit or scope thereof has ordinary skill in the art. It is obvious to them. Therefore, the above-described embodiments should be regarded as illustrative rather than restrictive, and thus, the present invention is not limited to the above description and may be modified within the scope of the appended claims and their equivalents.

10: housing
100: drive unit
11: lower housing
110: output shaft
12: upper housing
200: power transmission unit
210: first power transmission unit
211: first stop
212: second stop
220: elastic control unit
230: elastomer
240: second power transmission unit
241: anti-rotation part
300: power converter
310: cam plate
311, 312: cam groove
320: camshaft
330: bearing
500: gripper

Claims (10)

housing;
A driving unit coupled to a lower portion of the housing;
A gripper coupled to an upper portion of the housing; And
And a power conversion unit connected to the driving unit to convert the rotational movement by the driving unit into the linear movement of the gripper.
An elastic body is provided between the driving unit and the power conversion unit.
Rotation force by the drive unit is transmitted to the power conversion unit through the elastic body,
An outer circumferential surface of the drive unit is coupled to a first power transmission unit for transmitting a driving force, an elastic control unit is coupled to the first power transmission unit, and the elastic body is coupled to the elastic control unit,
On the other hand, the power conversion unit,
A second power transmission unit coupled to the elastic body;
A cam plate connected to the second power transmission unit and having a plurality of cam grooves;
A cam shaft inserted into the cam groove and positioned; And
And a gripper connected to the camshaft.
In addition, the outer circumferential surface of the first power transmission portion is formed in the radial direction, two stops are provided spaced apart by a predetermined interval along the circumferential direction, the outer peripheral surface of the second power transmission portion along the axial direction of the drive shaft output shaft An elastic gripper device further comprising a rotation preventing portion formed to protrude long and positioned between the stop portions. delete delete The method of claim 1,
And the cam plate is configured to rotate together with the second power transmission portion. The method of claim 4, wherein
The elastic body is an elastic gripper device coupled to the elastic control unit and the second power transmission unit. delete The method of claim 5,
And the elastic body is a torsion spring. The method of claim 4, wherein
And the camshaft moves along the cam groove formed in the cam plate by the rotation of the cam plate. The method of claim 5,
The elastic control unit is fixed to the outer circumferential surface of the first power transmission unit,
Elastic gripper device configured to change the position through the rotation on the outer peripheral surface of the first power transmission portion. The method of claim 9,
Elastic gripper device to change the elastic force of the elastic body between the elastic control part and the second power transmission portion by the rotation of the elastic control unit.

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