JP2001205586A - Suction pad - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a suction pad ensuring suction of a work on the surface of which oil films or water droplets are deposited. SOLUTION: The suction pad 10 has a recess 20 peripherally formed on suction plane 14A of a skirt portion 14 and a recess 22 formed radially thereon, both being 0.5 mm or more in width and 0.3 mm or more in depth. If there are many oil films or water droplets deposited on the surface of a work, the oil films or others are put into the recesses 20, 22 and removed. Therefore, the suction pad 30 ensures suction of the work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suction pad which is connected to a vacuum source and suctions and grips a workpiece by a negative pressure.

[0002]

2. Description of the Related Art Conventionally, a suction pad connected to a vacuum generating source has been used for transporting a work (adsorbed object) at a factory or the like. However, with this suction pad, for example, when transporting a work in which a thin oil film is formed on the surface of a steel plate for a vehicle or the like, the suction state is unstable, such as the suctioned work slipping due to oil, and at worst, There was also a risk of falling.

On the other hand, Japanese Patent Application Laid-Open No. 9-11172 proposes a method for improving the slip and drop of a work to which an oil film or water droplets adhere.

In Japanese Patent Application Laid-Open No. 9-11172, as shown in FIG. 5, a suction pad 100 is provided with a substantially cylindrical base 10.
2 and a skirt portion 104 extending substantially conically from the base portion 102 of a cup body 106 integrally formed of an elastic material such as rubber.
8 is provided so as to open substantially at the center of the skirt portion 104.

The suction surface 1 of the skirt 104
04A, a plurality of circumferential grooves 110 which perform an anti-slip action and a plurality of radial grooves 112 intersecting with the grooves 110 are formed. These grooves 110 and 112 have, for example, a width of 0.1 mm.
It has a thin notch shape of about 1 to 0.3 mm.

When connecting the suction pad 100 to a cargo handling device such as a robot arm, the base 102 is attached to an arm tip (not shown) of the robot arm.
This is performed by connecting a pipe or a tube (not shown) connected to a vacuum source such as a suction pump to the hole 108,
As a result, the suction pad 100 is
, A high suction force can be generated on the suction surface 104A side.

[0007] The suction pad 100 constructed as described above.
Is moved by the driving of the robot arm, the outer peripheral edge of the skirt portion 104 is brought into contact with the work, and the inside of the skirt portion 104 is made into a decompression space by the operation of the suction pump, and the skirt portion 104 is adapted to the shape of the surface to be attracted. By deforming, the work is sucked on the suction surface 104A.

At this time, when the suction surface 104A of the skirt portion 104 elastically deformed by the pressure reduction comes into contact with the work so as to be pressed against the work, the cuts in the circumferential and radial directions (grooves 110 and 112) are, for example, 0.1 mm. 5mm
Spread to the extent. As a result, in the skirt portion 104 that is in close contact with the work, the grooves 110 and 112 act as pressure reduction action areas, and the pressure reduction action area is kept wide, thereby improving the suction force.

Further, even when an oil film or water droplets adhere to the surface to be sucked of the work, the oil film or water droplets interposed between the suction surface 104A and the surface of the work are not removed by the circumferential groove 1.
10 will be scraped off by the notch forming and further collected and removed at the center of the cup body 106 by a radial groove 112 intersecting the circumferential groove 110, thereby allowing the skirt 104 to work against the workpiece. As the degree of adhesion increases, the drag against sliding improves.

Further, due to the edge effect of the grooves 110 and 112 deforming so as to reduce the cross-sectional area by the depressurizing action, the frictional force against slippage is improved, and displacement and drop due to slippage of the work are prevented. That is.

[0011]

However, in the conventional suction pad 100, since the grooves 110 and 112 have a small cut shape, the skirt portion 1 is sucked by the work.
When the elastic deformation of the groove 04 occurs (the groove width increases), the stress concentrates near the groove bottom (cut end). For this reason, due to the repeated deformation (expansion / reduction of the groove width) of the skirt portion 104 due to the suction / separation of the work, a crack or the like is likely to be formed from the vicinity of the groove bottom, and a new problem such as a decrease in durability arises.

Further, since the sectional area of the groove is small, there is a possibility that the oil film or the like cannot be completely removed from the surface to be sucked of the work depending on the thickness (the amount of adhesion) of the oil film or the like. Here, it is conceivable to improve the dischargeability by increasing the number of grooves, but it cannot be simply solved because of the above-mentioned balance with durability.

Further, since fine dust and foreign matter contained in the oil film or the like may easily accumulate in the cut portion, there is a concern that the oil discharge performance at the cut portion may be deteriorated.

Further, in order to form the grooves 110 and 112, it is necessary to cut the suction surface 104A after the suction pad 100 is formed.

The present invention has been made in view of the above-mentioned facts, and has as its object to provide a suction pad which can surely adsorb a work having an oil film or water droplets adhered to its surface, has excellent durability, and suppresses an increase in manufacturing cost. Make it an issue.

[0016]

According to a first aspect of the present invention, there is provided a base connected to a vacuum generating source, a skirt provided integrally with the base, and a vacuum generating unit provided on the base. And a passage portion for communicating a source with the inner peripheral surface side of the skirt portion, wherein the suction pad is formed on the inner peripheral surface of the skirt portion in a circumferential direction of the inner peripheral surface. A first recess and a second recess formed in the radial direction connected to the first recess are provided, and the first recess and the second recess have a width dimension of 0.5 mm or more. And the depth dimension is 0.3 mm or more.

In the suction pad according to the first aspect, the first concave portion formed in the circumferential direction on the inner peripheral surface of the skirt portion, and
By setting the width of the second recess formed in the radial direction to 0.5 mm or more and the depth to 0.3 mm or more, a wide cross-sectional area of the recess is ensured. For this reason, even when the amount of an oil film, water droplets, or the like adhering to the work surface is large, the oil film or the like can sufficiently enter the recess when the inner peripheral surface is in close contact with the work.

Therefore, the oil film and the like on the surface to be sucked of the work are more removed by the concave portion, and the work can be surely sucked.

Further, in the case where the inner peripheral surface portion is repeatedly deformed due to suction and release of the work, the width of the concave portion is 0.5 m.
m or more, the stress applied to the bottom surface of the concave portion is reduced. Therefore, cracks and the like hardly occur, and the durability is improved.

Further, when forming the concave portion, the width of the concave portion is widened so that the forming process can be performed by using a mold, and the concave portion can be formed simultaneously with the forming of the suction pad. Therefore,
Providing the recess does not increase the manufacturing cost.

According to a second aspect of the present invention, in the suction pad according to the first aspect, the second concave portion formed in the radial direction is connected to the passage portion.

In the suction pad according to the second aspect, since the second concave portion is connected to the passage portion, the oil that has entered the first concave portion and the second concave portion connected to the first concave portion is
Outflow to the passage portion side is enabled. Therefore, the oil discharging property by the first and second concave portions is further improved.

The invention described in claim 3 is the first invention.
Alternatively, in the suction pad according to claim 2, a surface roughness of the inner peripheral surface of the skirt portion is 25 μm or more except at least a region where the first concave portion and the second concave portion are formed. It is characterized by having.

In the suction pad according to the third aspect, the surface roughness of the inner peripheral surface of the skirt portion other than at least the region where the first and second concave portions are formed is set to 25 μm or more, so that The frictional resistance at the close contact portion with the work on the peripheral surface increases. For this reason, the braking action against the slip of the work is improved, and the work can be more reliably sucked.

Further, since the surface roughness of the inner peripheral surface can be easily processed to a predetermined value or more by molding, the production cost does not increase here.

[0026]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] FIGS. 1 and 2 show a suction pad according to a first embodiment of the present invention.
As shown in the figure, a suction pad 10 has a substantially cylindrical base 12 serving as a mounting portion to a robot arm or the like, and the base 12
And a skirt portion 14 extending substantially in the shape of a cone.
The suction pad 10 is formed of an elastic material such as rubber.

The base 12 is provided with a passage 16 for communicating a vacuum source connected to the base 12 with the inside of the suction pad. The passage 16 is provided on the mounting surface 1 of the base 12.
It extends stepwise from the 2A side toward the suction surface 14A side of the skirt portion 14.

As shown in FIG. 2 (B), the skirt portion 14 is formed so that its thickness decreases from the base portion 12 side to the outer peripheral end portion 14B side.

The suction surface 14A of the skirt portion 14 is formed with a recess 20 having a substantially rectangular cross section along the circumferential direction, and further includes four rectangular cross sections arranged at 90 ° intervals. The recess 22 is formed along the radial direction. One end of each of the four recesses 22 is connected to the recess 20,
The other end is connected to the passage 16.

In this embodiment, the diameter D of the suction pad 10 is 105 mm, and the width W1 of the recess 20 is about 3 m.
m, and the width W2 of the recess 22 is about 4 mm. In addition, recess 2
Each of the depths H1 and H2 of 0 and 22 is about 1 m.
m. Further, these concave portions 20 and 22 are formed simultaneously by a mold when the suction pad 10 is formed.

Next, the operation of the present embodiment will be described.

The suction pad 10 according to the present embodiment has a concave portion 20 formed in the circumferential direction on the suction surface 14A of the skirt portion 14.
And the width dimension of the concave portion 22 formed in the radial direction is 0.5 mm
As described above, since the depth dimension is 0.3 mm or more, a wide sectional area of each concave portion is secured. For this reason, even when the amount of oil film, water droplets, etc. adhering to the work surface is large,
When A comes into close contact with the work or the like, the oil film or the like on the work adsorption surface is more removed by the concave portions 20 and 22, and the work can be surely adsorbed.

Further, the suction surface 1 due to the suction / release of the work.
Even in the repeated deformation of the 4A portion, the stress applied to the bottom portions of the concave portions 20 and 22 is reduced, and the durability is improved.

Further, the concave portions 20 and 22 are
By simultaneously processing at the time of molding, the production cost does not increase.

The number of the recesses 20 and 22 and the width and depth dimensions are not limited to the present embodiment, but can be changed as appropriate according to the size of the suction pad.

The cross-sectional shape of the concave portion is not limited to the rectangular shape as in the present embodiment, but may be a substantially semicircular shape.
Thereby, the stress applied to the concave portion can be further reduced.

[Second Embodiment] Next, a second embodiment of the present invention will be described. In this second embodiment,
Since the configuration is almost the same as that described in the first embodiment, the same components are denoted by the same reference numerals and description thereof will be omitted.

FIGS. 3 and 4 show a suction pad according to a second embodiment of the present invention. As shown in the drawing, the suction pad 30 of the present embodiment has a suction surface 14C of the skirt portion 14 that has been subjected to a satin finish (texture process), and fine irregularities are randomly formed on the surface of the suction surface 14C. Is formed.

The minute uneven portion is provided in an area surrounded by the concave portion 20 and the concave portion 22 on the suction surface 14C, and has a surface roughness of about 50 to 100 μm. Here, the surface roughness is a value measured by the so-called arithmetic average roughness (Ra). The minute irregularities are simultaneously processed by a mold when the suction pad 30 is formed.

Therefore, in the present embodiment, the suction surface 14
By providing a region having a surface roughness of 25 μm or more in C, the frictional resistance at the contact portion between the suction surface 14C and the work increases, and the braking action against slippage improves. Therefore, the work can be more reliably sucked. In addition, since the region where the surface roughness is equal to or more than the predetermined value can be processed by molding using a mold, the increase in manufacturing cost can be suppressed.

In the present embodiment, the minute irregularities provided on the suction surface 14A have an irregular pattern. However, the irregularities may have a constant pattern such as a knurl.

[0043]

As described above, in the suction pad according to the first aspect, the first concave portion formed in the circumferential direction and the second concave portion formed in the radial direction are formed on the inner peripheral surface of the skirt portion. By setting the width of the concave portion to be 0.5 mm or more and the depth to be 0.3 mm or more, the work can be surely adsorbed even when the amount of oil film, water droplets, etc. attached to the work surface is large. Further, even when the inner peripheral surface portion is repeatedly deformed due to the adsorption and desorption of the work, the stress applied to the bottom portion of the concave portion is reduced, so that cracks and the like are less likely to be formed, and the durability is improved. Further, since the concave portion can be processed simultaneously with the formation of the suction pad, the production cost does not increase.

According to the second aspect of the present invention, since the second concave portion is connected to the passage portion, the oil which has entered the first concave portion and the second concave portion connected to the first concave portion can be removed. ,
It is possible to flow out to the passage portion side, and the oil discharging property is further improved.

Further, the suction pad according to claim 3 is
By setting the surface roughness of the inner peripheral surface of the skirt other than at least the region where the first and second concave portions are formed to 25 μm or more, the frictional resistance at a contact portion of the inner peripheral surface with the work increases. In addition, the braking action against slippage is improved, and the work can be more reliably sucked.

In addition, since the surface roughness can be easily processed to a predetermined value or more by molding, an increase in manufacturing cost can be suppressed.

[Brief description of the drawings]

FIG. 1 is a perspective view of a suction pad according to a first embodiment of the present invention as viewed from a skirt portion side.

FIGS. 2A and 2B show a suction pad according to the first embodiment of the present invention, wherein FIG. 2A is a bottom view and FIG. 2B is a sectional view taken along line 2B-2B in FIG.

FIG. 3 is a perspective view of a suction pad according to a second embodiment of the present invention as viewed from a skirt portion side.

4A and 4B show a suction pad according to a second embodiment of the present invention, wherein FIG. 4A is a bottom view and FIG. 4B is a sectional view taken along line 4B-4B in FIG.

5A and 5B show a conventional suction pad, FIG. 5A is a bottom view, and FIG. 5B is a partial cross-sectional view in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Suction pad 12 Base 14 Skirt part 14A Suction surface (inner peripheral surface) 14C Suction surface (inner peripheral surface) 16 Passage (passage part) 20 Depression (first depression) 22 Depression (second depression) 30 Suction pad

Claims (3)

[Claims] 1. A base connected to a vacuum generation source, a skirt provided integrally with the base, and a communication provided between the vacuum generation source and an inner peripheral surface of the skirt provided on the base. And a passage portion for causing the first dent portion to be connected to the first concave portion formed on the inner peripheral surface of the skirt portion in a circumferential direction of the inner peripheral surface. And a second recess formed in the radial direction. The first recess and the second recess have a width dimension of 0.5.
a suction pad having a depth of at least 0.3 mm and a depth of at least 0.3 mm. 2. The method according to claim 2, wherein the second recess formed in the radial direction includes:
The suction pad according to claim 1, wherein the suction pad is connected to the passage portion. 3. A surface roughness of the inner peripheral surface of the skirt portion other than at least a region where the first concave portion and the second concave portion are formed has a surface roughness of 25 μm or more. The suction pad according to claim 1 or 2, wherein the suction pad is used.