WO2018003767A1

WO2018003767A1 - Cushion pad and robot arm using same

Info

Publication number: WO2018003767A1
Application number: PCT/JP2017/023487
Authority: WO
Inventors: 慶詞大野; 隆弘浜口; 慎吾長島
Original assignee: キョーラク株式会社
Priority date: 2016-06-30
Filing date: 2017-06-27
Publication date: 2018-01-04
Also published as: JP6730595B2; JP2018001328A

Abstract

[Problem] To provide: a cushion pad, which is capable of handling a variety of products and of being operated for long periods even in robot arms that are not provided with a cushioning device, and for which the load on the robot arm is reduced; and a robot arm using same. [Solution] A cushion pad (10) used for polishing an object S to be polished is provided with multiple pads (11, 12) having different hardness in multiple layers. The multiple pads (11, 12) comprise a first pad (11) located on the driving side and a second pad (12), which is detachably installed on the polishing side of the first pad (11) and has a polishing material (122) attached to the polishing side thereof. The second pad (12) has a hardness that is softer than the first pad (11).

Description

Cushion pad and robot arm using the same

The present invention relates to a cushion pad used for polishing an object to be polished and a robot arm using the same.

Conventionally, a grinding device and a polishing device for grinding and polishing various intermediate products to obtain a final product are known (for example, refer to Patent Document 1 for a grinding device).

Patent Document 1 discloses that a grinding robot automatically grinds and polishes a processing target surface having an arbitrary three-dimensional curved shape such as a cast part based on position and orientation information from a master arm. Is provided as a slave, and a shock absorber is provided between the tip of the robot arm and the grinding tool, which can be displaced in the tool pressing direction and can follow the unevenness of the workpiece surface. The controller has a teaching function. Specify the area to be automatically ground by teaching the tool position / posture of multiple points on any 3D curved surface of the workpiece, and interpolate the position / posture of the tool path in the polygon connecting the same points There is disclosed a grinding apparatus that calculates and allows the tool position / posture to be regenerated and moved in accordance with the calculated tool path.

However, as shown in FIG. 5, the surface of the object to be ground S ′ can be displaced between the polishing unit 25 ′ attached to the tip of the robot arm 24 ′ and the grinding tool 10 ′ and can be displaced in the tool pressing direction. In the configuration provided with a shock absorber D (damper) capable of following the above, it is necessary to finely adjust the shock absorber D in accordance with the shape of each object to be ground S ′. There was a problem that it was not suitable for time operation. Further, since the apparatus is large, there is a problem that the load on the robot arm 24 'is large.

JP-A-6-214633

The present invention has been made based on such circumstances, and the purpose of the present invention is to support a variety of products even with a robot arm that does not include a shock absorber, and can be operated for a long time, and the load on the robot arm. An object of the present invention is to provide a cushion pad and a robot arm using the same.

The present invention is grasped by the following composition.
(1) A first aspect of the present invention is a cushion pad used for polishing an object to be polished, which includes a plurality of pads having different hardnesses, and the plurality of pads are positioned on a driving side. And a second pad removably attached to the polishing side of the first pad, the second pad having an abrasive adhered to the polishing side. The pad has a hardness that is softer than the first pad.

(2) In the configuration of (1), the first pad has a first lower surface fastener attached to the polishing side, and the second pad is attached to the driving side of the second upper surface fastener. The second pad is attached to the first pad by engaging the second upper surface fastener with the first lower surface fastener.

(3) In the configuration of (1), the plurality of pads further include a third pad that is detachably attached between the first pad and the second pad, and the third pad is the first pad. It is softer and harder than the second pad.

(4) In the configuration of (1), the second pad has a thickness of 3 mm to 10 mm.

(5) In the configuration of (1), the total thickness including the first pad and the second pad is 5 mm to 20 mm.

(6) In the configuration of (1), the first pad has a load pressure of 8000 Pa to 28000 Pa by the international unit system SI as the hardness, and the second pad similarly has a load pressure of 1400 Pa to 21000 Pa.

(7) A second aspect of the present invention is a robot arm used for polishing an object to be polished, the arm, a polishing unit attached to the tip of the arm, and provided at the tip of the polishing unit A rotor and a cushion pad attached directly or indirectly to the rotor, wherein the cushion pad includes a plurality of pads having different hardnesses, and the plurality of pads are driven. A first pad located on the side, and a second pad removably attached to the polishing side of the first pad, the second pad having an abrasive adhered to the polishing side. The second pad has a softness that is softer than the first pad.

(8) In the configuration of (7), the first pad is indirectly attached to the rotor via an intermediate member.

According to the present invention, it is possible to provide a cushion pad that can handle various products even with a robot arm that does not include a shock absorber, can be operated for a long time, and has a low load on the robot arm, and a robot arm using the cushion pad. Can do.

It is a figure explaining one situation where the robot arm for grinding concerning this embodiment polishes a ground object. It is a figure explaining the other situation where the robot arm for grinding | polishing which concerns on this embodiment grind | polishes a to-be-polished body. It is a figure explaining an example of the cushion pad for grinding concerning this embodiment. It is a figure explaining the other example of the cushion pad for grinding | polishing which concerns on this embodiment. It is a figure explaining the robot arm for conventional grinding | polishing. It is a figure explaining thickness measurement about pressure measurement to a cushion pad for grinding. Similarly, it is a figure explaining a load measurement about the pressure measurement of the cushion pad for grinding | polishing.

DETAILED DESCRIPTION Hereinafter, embodiments for carrying out the present invention (hereinafter, embodiments) will be described in detail with reference to the accompanying drawings.

This embodiment is a cushion pad 10 used for polishing the object to be polished S and a robot arm 20 using the same. Each will be described below.

(Robot arm)
First, the robot arm 20 will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the robot arm 20 includes a base 21, a rotary base 22, a motor unit 23, an arm 24, a polishing unit 25, and a cushion pad 10. The arm 24 is provided with a cable 26 necessary for control and the like.

The rotating pedestal 22 is fixed on the base 21, and the motor unit 23 is rotatably mounted on the rotating pedestal 22. An arm 24 extends from the motor unit 23. The arm 24 includes a first arm unit 241 that is pivotally supported by the motor unit 23 and a second arm unit that is pivotally supported by the first arm unit 241. 242 and a third arm portion 243 that is pivotally supported by the second arm portion 242. The 3rd arm part 243 is constituted so that the tip side may rotate. A polishing unit 25 is pivotally supported at the tip of the third arm unit 243, and the motor unit 23, the arm 24, and the polishing unit 25 operate according to a program set according to the shape and material of the object S to be polished. .

1 and 2 show a case of an automobile spoiler in which the object to be polished S is formed of a resin. FIG. 1 shows a portion where the straight central portion of the spoiler is being polished, and FIG. 2 shows a portion where the end portion SE having a complicated uneven shape is being polished. The spoiler is designed from the viewpoint of design in addition to the viewpoint of aerodynamics. In particular, the end portion SE often represents a spoiler characteristic, and is a part that attracts the attention of an automobile user. Therefore, as shown in the figure, the shape of the end portion SE of the spoiler often has a complex outline, and when polishing, careful attention is required to follow the shape well.

The polishing portion 25 is a support portion 251 that is pivotally supported by the arm 24 (third arm portion 243), a rotor 252 that is rotatably attached to the tip of the support portion 251, and a removably attached to the rotor 252. The cushion pad 10 is provided. The polishing unit 25 will be described together with the cushion pad 10 in detail.

In the present embodiment, the robot arm 20 to which the cushion pad 10 can be attached is not limited to the illustrated one. For example, FIG. 1 and FIG. 2 show a floor-standing type in which the base 21 is placed on the floor as the robot arm 20, but in addition to this, it is suspended from a desktop type or an installed beam. A hanging type may be used. Further, the aspect of the arm 24 may be constituted by two arm portions instead of the three arm portions.

(Cushion pad)
Next, the cushion pad 10 is demonstrated using FIG.3 and FIG.4. The cushion pad 10 used for polishing the workpiece S includes a plurality of pads having different hardnesses. FIG. 3 shows an example of two layers of two pads 11 and 12, and FIG. Examples of three layers by three

pads

11, 12, 13 are shown.

First, an example of two layers will be described with reference to FIG. The cushion pad 10 is detachably attached to the first pad 11 located on the support portion 251 side (drive side) of the polishing portion 25 and the side S of the first pad 11 to be polished (polishing side). 2 pads 12 are included.

The first pad 11 includes a first pad main body 110, a loop-shaped first upper surface fastener 111 adhered to the driving side thereof, and a hook-shaped first lower surface fastener 112 adhered to the polishing side thereof. is doing. The first pad 11 is detachably attached to the rotor 252 provided on the support portion 251 of the polishing portion 25 via the first upper surface fastener 111, or indirectly via the intermediate member 253. It is done. A hook-like lower surface fastener (not shown) is provided on the polishing side of the rotor 252 or the intermediate member 253, and the first upper surface fastener 111 is engaged with the lower surface fastener.

The second pad 12 includes a second pad main body 120, a loop-shaped second upper surface fastener 121 attached to the driving side thereof, and abrasive paper 122 attached to the polishing side (the abrasive is other than abrasive paper). It may be that of the embodiment.). The second pad 12 is detachably attached to the first pad 11 by the second upper surface fastener 121 engaging the first lower surface fastener 112.

The first pad 11 and the second pad 12 have different hardness, and the second pad 12 has a softer hardness than the first pad 11. Here, as to the hardness of the first pad 11 and the second pad 12, as will be described in detail later as an example, the load pressure required to displace each of the four pads stacked by using a force gauge by 3 mm. Define as

In this case, the first pad 11 is preferably 8000 Pa to 28000 Pa, and the second pad 12 is preferably 1400 Pa to 21000 Pa. The first pad 11 is combined so that the load pressure of the second pad 12 is always greater than the load pressure of the second pad 12. When the first pad 11 is less than 8000 Pa, the first pad 11 is distorted together with the second pad 12 due to the centrifugal force at the time of rotation. When the second pad 12 is less than 1400 Pa, the second pad 12 is likely to be separated from the object to be polished S due to centrifugal force during rotation. Further, the second pad 12 is twisted and distorted due to the frictional force between the object to be polished S and the polishing material 122, and the polishing accuracy is significantly reduced. On the other hand, if it exceeds 21000 Pa, a repulsive force is generated in the second pad 12 and it becomes difficult to adhere to the object to be polished S.

The second pad 12 having the polishing paper 122 is made of a soft material (sponge-like) to follow the shape of the object to be polished S, but when rotated while attached to the rotor 252 or the intermediate member 253, The second pad 12 may become flat due to centrifugal force and be separated from the object to be polished S. Therefore, by sandwiching the hard first pad 11 between the rotor 252 or the intermediate member 253 and the second pad 12, the second pad 12 is flattened by the centrifugal force and separated from the object to be polished S. The present inventor has found that this can be prevented.

For example, when the cushion pad 10 is composed of only the second pad 12, the thickness reduction due to centrifugal force depends on its original thickness. The amount of decrease will increase. As a result, the position of the robot arm 20 is adjusted when the polishing paper 122 of the second pad 12 is aligned with the object to be polished S when it is stopped, that is, before the polishing operation is started, and when the second pad 12 is rotated. A difference in distance (between the polishing unit 25 and the object to be polished S) appears when the rotation is performed. In order to cope with this difference in distance by controlling the robot arm 20, in consideration of mass production in a production line that must respond to subtle dimensional differences of individual objects to be polished S. Is not realistic.

In addition, the thin and soft second pad 12 alone does not sufficiently perform the cushion function and cannot cope with the fine irregularities of the object S to be polished.

On the other hand, as described above, the hard first pad 11 that is difficult to be deformed by centrifugal force is provided on the second pad 12, and the cushion pad 10 is made of two layers of soft and hard when viewed from the object S to be polished. Thus, even when the polishing unit 25 rotates, the thickness of the second pad 12 hardly changes, and the cushion pad 10 having high followability to the object to be polished S and the robot arm 20 using the same can be realized. This is presumably because the first pad 11 absorbs the centrifugal force applied to the second pad 12 to some extent by providing the hard first pad 11 on the drive side of the soft second pad 12. Here, from the viewpoint of followability to the object to be polished S, the thickness of the second pad 11 is preferably 3 to 10 mm, and the total thickness of the cushion pad 10 including the first pad 11 and the second pad 12 is preferably 5 to 20 mm. .

Next, an example of three layers will be described with reference to FIG. The cushion pad 10 includes a first pad 11 positioned on the driving side of the support unit 251 of the polishing unit 25, a third pad 13 detachably attached to the polishing side of the first pad 11, and polishing of the third pad 13. A second pad 12 is removably attached to the side.

The third pad 13 has a third pad main body 130, a loop-shaped third upper surface fastener 131 adhered to the driving side thereof, and a hook-shaped third lower surface fastener 132 adhered to the polishing side thereof. is doing. The third pad 13 is detachably attached to the first pad 11 by engaging the third upper surface fastener 131 with the first lower surface fastener 112 of the first pad 11, and the third lower surface fastener 132 is attached to the second pad 12. By being engaged with the second upper surface fastener 121, the second pad 12 is detachably attached. The third pad 13 is softer than the first pad 11 and harder than the second pad 12.

The third pad 13 is sandwiched between the first pad 11 and the second pad 12, and the cushion pad 10 has three layers of soft, medium and hard as viewed from the object S to be polished. The followability to S can be further improved. Of course, the number of multiple layers is not limited to two or three, and may be four or more if the order of hardness is “soft → hard” when viewed from the object S to be polished.

(Effect of embodiment)
With this configuration, the present embodiment has the following effects.
(1) Since the cushion pad 10 serves as a shock absorber (damper, suspension), the followability to the object to be polished S can be improved without a mechanical shock absorber. As a result, it is possible to finish the object to be polished S smoothly without leaving any excessive burrs.
(2) Since the polishing unit 25 can be made smaller and lighter than before, the load on the robot arm 20 can be reduced.
(3) Since the structure of the cushion pad 10 is simple, disassembly, parts replacement, etc. are easy.
(4) The impact when the polishing unit 25 of the robot arm 20 is first applied to the object to be polished S, which may occur when a shock absorber is provided, can be lost.

(Example)
As an example, the load pressures of the first pad 11 and the second pad 12 were measured by the following procedures (1) to (5) using eight types of pads.
(1) The 1st pad 11 or the 2nd pad 12 was piled up into 4 parts.
(2) The glass petri dish 30 was placed on the stacked first pad 11 or second pad 12, and the thickness was measured using the height gauge 31 in a state where there was no load other than the glass petri dish 30 (see FIG. 6). A glass petri dish 30 having a diameter of about 160 mm and a weight of 56 g was used.
(3) Next, a load was applied to the upper portion of the glass petri dish 30 with the force gauge 32, and the load value when the thickness was displaced by 3 mm was measured (see FIG. 7).
(4) The test of (3) above was performed three times, and the average of each load value (N: Newton) was recorded.
(5) The cross-sectional area of the first pad 11 or the second pad 12 was measured, and the pressure (Pa: Pascal) was calculated from the load value.

Here, as the height gauge 31, a height gauge manufactured by Mitutoyo Co., Ltd. (model: 514 series standard height gauge HS-60) is used, and as the force gauge 32, a digital force gauge manufactured by Nidec Shinpo Co., Ltd. (model: Leotester FGRT- 10) was used. Table 1 shows the results of the load pressure of the second pad 12 measured by the above (1) to (5) and the suitability of the second pad 12 to be used. In Table 1, “Thickness under no load”, “Thickness under load”, and “Thickness displacement” are values obtained when four divided pads are stacked, and “Cross sectional area during measurement” is divided into four. “Pad diameter” represents the diameter of the pad before being divided into four parts, respectively.

Regarding the first pad 11, in Comparative Examples A1 to A4, the first pad 11 was distorted together with the second pad 12 due to centrifugal force during rotation. On the other hand, in Comparative Example A5, it was too hard and the buffering property against the object to be polished S was lowered. On the other hand, in Examples A1 to A3 (load pressure: 8000 Pa to 28000 Pa), without causing such inconvenience, while maintaining the buffer function, the distortion of the second pad 12 is suppressed and the followability is high. Was possible.

Regarding the second pad 12, in Comparative Examples B1 and B2, the polishing surface was raised by the centrifugal force of the rotation of the second pad 12, and polishing teaching became difficult. Further, the polishing became unstable due to the influence of the shearing force in the rotating direction generated when contacting the object to be polished S. On the other hand, in Comparative Examples B3 and B4, the polishing surface no longer follows the surface of the object S to be polished. Furthermore, the pressing became too strong and the rotation (polishing) became unstable. On the other hand, in Examples B1 to B4 (load pressure: 1400 Pa to 21000 Pa), polishing with high followability was possible without causing such inconvenience.

As mentioned above, although this invention was demonstrated using embodiment, it cannot be overemphasized that the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. Further, it is apparent from the scope of the claims that embodiments with such changes or improvements can also be included in the technical scope of the present invention. In addition, this embodiment can be applied even if the to-be-polished body S is a molded product by blow molding or a molded product by injection molding.

DESCRIPTION OF SYMBOLS 10 ... Cushion pad 11 ... 1st pad 110 ... 1st pad main body 111 ... 1st upper surface fastener 112 ... 1st lower surface fastener 12 ... 2nd pad 120 ... 2nd pad main body 121 ... 2nd upper surface fastener 122 ... Polishing paper (polishing) Material)
DESCRIPTION OF SYMBOLS 13 ... 3rd pad 130 ... 3rd pad main body 131 ... 3rd upper surface fastener 132 ... 3rd lower surface fastener 20 ... Robot arm 21 ... Base 22 ... Rotation base 23 ... Motor part 24 ... Arm 25 ... Polishing part 251 ... Support part 252 ... Rotor 253 ... Intermediate member 30 ... Glass Petri dish 31 ... Height gauge 32 ... Force gauge

Claims

A cushion pad used for polishing an object to be polished,
A plurality of pads with different hardnesses are provided in multiple layers,
The plurality of pads are
A first pad located on the drive side;
A second pad removably attached to the polishing side of the first pad, the second pad having an abrasive adhered to the polishing side,
The cushion pad, wherein the second pad has a softness that is softer than the first pad.
The first pad has a first lower surface fastener attached to the polishing side;
The second pad has a second upper surface fastener attached to its drive side;
The cushion pad according to claim 1, wherein the second pad is attached to the first pad by engaging the second upper surface fastener with the first lower surface fastener.
The plurality of pads further includes a third pad removably attached between the first pad and the second pad;
The cushion pad according to claim 1, wherein the third pad is softer than the first pad and harder than the second pad.
The cushion pad according to claim 1, wherein the second pad has a thickness of 3 mm to 10 mm.
The cushion pad according to claim 1, wherein the cushion pad has a total thickness of 5 mm to 20 mm including the first pad and the second pad.
The cushion pad according to claim 1, wherein the first pad has a load pressure of 8000 Pa to 28000 Pa according to the international unit system SI as the hardness, and the second pad similarly has a load pressure of 1400 Pa to 21000 Pa.
A robot arm used for polishing an object to be polished,
Arm,
A polishing part attached to the tip of the arm;
A rotor provided at the tip of the polishing unit;
A cushion pad attached directly or indirectly to the rotor,
The cushion pad is provided with a plurality of pads having different hardness in multiple layers,
The plurality of pads are
A first pad located on the drive side;
A second pad removably attached to the polishing side of the first pad, the second pad having an abrasive adhered to the polishing side,
The robot arm according to claim 1, wherein the second pad has a softness that is softer than the first pad.
The robot arm according to claim 7, wherein the first pad is indirectly attached to the rotor via an intermediate member.