JP2021084144A - Vacuum suction nozzle - Google Patents

Abstract

To suppress unintended closing of an opening of a vacuum suction nozzle.SOLUTION: A vacuum suction nozzle for sucking an object includes a suction surface which abuts on the object, a plurality of suction holes arranged on the suction surface, a plurality of individual flow channels which are respectively extended from the plurality of suction holes, and a common flow channel which is connected to the plurality of individual flow channels and is connected to an external vacuum circuit. Each of the plurality of individual flow channels includes a valve seat having an opening, and a ball which is movably housed between the suction hole and the valve seat, is seated on the valve seat and closes the opening of the valve seat by a flow of the individual flow channel. A rib or a tapered surface, which is positioned between the suction hole and the valve seat and protrudes to an inner side as closer to the valve seat, is arranged on an inner wall of the individual flow channel.SELECTED DRAWING: Figure 1

Description

The techniques disclosed herein relate to vacuum suction nozzles.

Patent Document 1 discloses a vacuum suction nozzle. This vacuum suction nozzle is a vacuum suction nozzle that sucks an object, and has a suction surface that abuts on the object, a plurality of suction holes provided on the suction surface, and a plurality of individual flows extending from the plurality of suction holes. A passage and a common flow path connected to a plurality of individual flow paths and connected to an external vacuum circuit are provided, and each of the plurality of individual flow paths has a valve seat having an opening and a suction hole. It has a ball that is movably accommodated with and from the valve seat and is seated on the valve seat by the flow of individual flow paths to close the opening of the valve seat.

Japanese Unexamined Patent Publication No. 3-35990

Generally, in a vacuum suction nozzle, suction force can be maintained and suction support can be performed by closing the suction hole with an object. In this regard, in the above-mentioned vacuum suction device, even if some suction holes are not blocked by the object, the ball moves in the individual flow path instead, and the opening of the valve seat is closed. Therefore, the suction force of the entire suction device can be maintained, and the object can be sucked and supported. Therefore, in the above-mentioned vacuum suction device, it is desired to use a lightweight ball in consideration of the ease of movement of the ball. However, if an impact is generated on the vacuum suction device when there is no suction force, the impact may cause the ball to move between the suction hole and the valve seat, and the opening may be unintentionally blocked. In particular, in the case of a lightweight ball, since it moves with a small impact, the opening is likely to be blocked by the impact.

When the opening is closed by a ball due to an impact, the individual flow path having the closed opening is separated from the common flow path. As a result, the suction holes having the individual flow paths are not connected to the vacuum circuit (particularly the common circuit) at the time of vacuum suction, and the suction force cannot be applied to the object. Therefore, the weight of the object per unit area of the other suction holes connected to the vacuum circuit as usual exceeds the maximum value of the weight that the vacuum suction device can suck and hold. As a result, the vacuum suction nozzle cannot continue to suck and hold the object, and there is a risk of dropping the object. The present specification provides techniques that can solve or at least reduce these problems.

The vacuum suction nozzle disclosed in the present specification is a vacuum suction nozzle that sucks an object, and is provided from a suction surface that abuts on the object, a plurality of suction holes provided on the suction surface, and a plurality of suction holes, respectively. It is provided with a plurality of individual flow paths extending and a common flow path connected to the plurality of individual flow paths and connected to an external vacuum circuit.

Each of the plurality of individual flow paths is movably accommodated between the valve seat having an opening and the suction hole and the valve seat, and is seated on the valve seat by the flow of the individual flow paths to open the valve seat opening. Has a ball to occlude. The inner wall of the individual flow path is provided with a rib or a tapered surface that is located between the suction hole and the valve seat and protrudes inward as it approaches the valve seat.

The vacuum suction nozzle described above is provided with a rib or a tapered surface that protrudes inward as it approaches the valve seat on the inner wall of the individual flow path in the valve seat. According to such a configuration, when the ball unintentionally moves due to an impact in the absence of suction force, the ball first comes into contact with a rib or a tapered surface provided on the inner wall of the individual flow path. When the rib or tapered surface comes into contact with the ball, a frictional force is generated between the rib or tapered surface and the ball, and the force of movement of the ball is suppressed. Further, the rib or tapered surface can come into contact with the ball to mechanically interfere with the movement of the ball, thus preventing the ball from approaching the opening. Therefore, it is possible to prevent the ball from closing the opening in a state where a sufficient suction force is not applied to the ball by the vacuum suction nozzle.

In one embodiment of the technique, the vacuum suction nozzle may include a ball release. The ball release is provided on the main body plate facing a plurality of individual flow paths and on the main body plate, and is provided on a plurality of pushers extending toward the plurality of individual flow paths and on the main body plate, and is provided on the main body plate. It has at least one check valve that prohibits the flow towards the road and allows the flow in the opposite direction.

The check valve provided on the main body plate is configured to open at the time of vacuum suction and close at the time of suction failure (vacuum failure). Therefore, at the time of adsorption failure, the main body plate obstructs the flow of air from the external vacuum circuit to the individual flow path through the common flow path, and at the same time, the air flow moves toward the individual flow path in the common flow path. To do. As a result, the plurality of pushers provided on the main body plate are pushed into the individual flow paths facing each other. Therefore, the pusher can push the ball that blocked the opening of the valve seat at the time of vacuum suction in the direction of the suction hole. As a result, the ball whose opening is closed at the time of vacuum suction can be reliably released from the opening at the time of suction failure.

The configuration of the vacuum suction nozzle 10 is schematically shown. An enlarged view of part II in FIG. FIG. 2 is a cross-sectional view taken along the line III-III in FIG. 2, showing a rib 24 provided on the inner wall of the individual flow path 16. FIG. 2 is a cross-sectional view taken along the line IV-IV in FIG. 2, showing a valve seat 22 provided on the inner wall of the individual flow path 16. The correlation diagram between the force attracted by the ball 26 and the clearance between the ball 26 and the inner wall of the individual flow path 16 is shown. The figure explaining the operation of the vacuum suction nozzle 10 at the time of suction failure, particularly the operation of a ball release 40. The plan view which shows the top view of the ball release 40.

The vacuum suction nozzle 10 of the embodiment will be described with reference to the drawings. As shown in FIGS. 1 to 2, the vacuum suction nozzle 10 includes a suction surface 12, an individual flow path 16, and a common flow path 30. In the present specification, the cross-sectional shape of the vacuum suction nozzle 10 means a cross-sectional shape perpendicular to the flow direction of the common flow path 30. In the embodiment of the present specification, the cross-sectional shape of the vacuum suction nozzle 10 is not particularly limited, and may be a circle, an ellipse, an ellipse, or a polygon.

The suction surface 12 is a surface that comes into contact with an object that supports suction. The suction surface 12 has a plurality of suction holes 14. The shape and number of the plurality of suction holes 14 are not particularly limited, and can be designed as needed.

The plurality of suction holes 14 are provided with a plurality of individual flow paths 16 extending toward the inside of the vacuum suction nozzle 10. Each of the plurality of individual flow paths 16 has a valve seat 22 having an opening 20. Each of the plurality of individual flow paths 16 further has a ball 26 that is seated on the valve seat 22 by the flow of each individual flow path 16 and closes the opening 20 of the valve seat 22. The ball 26 has a diameter smaller than the inner diameter of the individual flow path 16, and is movably accommodated between the suction hole 14 and the valve seat 22.

A common flow path 30 is connected to the plurality of individual flow paths 16 through an opening 20. Then, the common flow path 30 is connected to an external vacuum circuit. Therefore, the suction hole 14 is connected to an external vacuum circuit through the individual flow path 16 and the common flow path 30. Therefore, when a negative pressure is applied by an external vacuum circuit, air is sucked into the vacuum suction nozzle 10 from the suction hole 14. At this time, if the object to be adsorbed and supported is in contact with the adsorption surface 12 and the plurality of adsorption holes 14 are blocked by the objects, a negative pressure is generated in each individual flow path 16 to cause the object to be adsorbed. Is vacuum-adsorbed. Further, even when some of the suction holes 14 are not blocked by the object, the balls 26 move in the individual flow paths 16 instead, and the opening 20 of the valve seat 22 is closed.

However, if an impact is generated on the vacuum suction nozzle 10 when there is no suction force, the ball 26 moves between the suction hole 14 and the valve seat 22 due to the impact, and the opening 20 is unintentionally closed. There is a risk of In particular, when the ball 26 is lightweight, it moves with a small impact, so that the opening 20 is likely to be blocked by the impact. Regarding this problem, the vacuum suction nozzle 10 of this embodiment adopts the configuration described below.

The inner wall of the individual flow path 16 is provided with a plurality of ribs 24 that are located between the suction hole 14 and the valve seat 22 and project inward as they approach the valve seat 22. The plurality of ribs 24 are not particularly limited, but are arranged at equal intervals along the circumferential direction in the individual flow paths 16. FIG. 3 is a cross-sectional view taken along the line III-III of FIG. The broken line in FIG. 3 shows the outer shape of the ball 26 housed in the individual flow path 16. As shown in FIG. 3, the rib 24 is a wall-shaped protrusion that protrudes inward, and is provided along the axial direction of the individual flow path 16. The shape and number of the ribs 24 are not particularly limited, and at least one rib 24 may be provided on the inner wall of the individual flow path 16. However, the height of the rib 24 is limited to a size that forms a first space 28 through which the ball 26 can pass at the center of the individual flow path 16. On the other hand, the inner surface of the valve seat 22 has a tapered surface shape as shown in FIGS. 2 and 4, and the diameter of the opening 20 defined at the center thereof is accommodated in the individual flow path 16. It is smaller than the diameter of the ball 26.

According to such a configuration, when the ball 26 is unintentionally moved by an impact without suction force, the ball 26 first comes into contact with the rib 24 provided on the inner wall of the individual flow path 16. When the rib 24 comes into contact with the ball 26, a frictional force is generated between the rib 24 and the ball 26, and the moving momentum of the ball 26 is suppressed. Further, when the rib 24 comes into contact with the ball 26, the movement of the ball 26 can be mechanically interfered with, and as a result, the ball 26 is prevented from approaching the opening 20. Therefore, it is possible to prevent the ball 26 from closing the opening 20 in a state where the ball 26 is not sufficiently attracted by the vacuum suction nozzle 10.

Here, as shown in FIG. 5, the force at which the ball 26 is sucked during vacuum suction changes according to the clearance between the ball 26 and the rib 24. Therefore, the sizes of the balls 26 and the ribs 24 may be appropriately designed based on the correlation diagram shown in FIG. A tapered surface may be formed on the inner wall of the individual flow path 16 instead of or in addition to the rib 24. This tapered surface may also be designed so that it is located between the suction hole 14 and the valve seat 22 and protrudes inward as it approaches the valve seat 22.

As shown in FIGS. 1, 6 and 7, the vacuum suction nozzle 10 further includes a ball release 40. The ball release 40 is provided on the main body plate 42 facing the plurality of individual flow paths 16 and on the main body plate 42, and is provided on the plurality of pushers 44 extending toward the plurality of individual flow paths 16 and the main body plate 42. It has at least one check valve 46 that prohibits the flow toward the individual flow paths 16 of the number of seals and allows the flow in the opposite direction. The check valve 46 is not particularly limited, but may be made of a flexible material such as rubber or an elastomer.

The check valve 46 provided on the main body plate 42 is configured to open at the time of vacuum suction and close at the time of suction failure (vacuum failure). Therefore, at the time of adsorption failure, the main body plate 42 obstructs the flow of air from the external vacuum circuit to the individual flow path 16 through the common flow path 30, and the air flow causes the individual flow path in the common flow path 30. Move towards 16. As a result, as shown in FIG. 6, the plurality of pushers 44 provided on the main body plate 42 are pushed into the individual flow paths 16 facing each other. Therefore, the pusher 44 can push the ball 26, which has closed the opening 20 of the valve seat 22 at the time of vacuum suction, in the direction of the suction hole 14. As a result, the ball 26 that closes the opening 20 at the time of vacuum suction can be reliably released from the opening 20 at the time of suction failure. After that, when the vacuum suction is performed again, the check valve 46 provided on the main body plate 42 opens, and the main body plate 42 moves along the air flow in the common flow path 30 so as to be separated from the individual flow paths 16. .. As a result, the plurality of pushers 44 move out of the individual flow paths 16 as shown in FIG. Therefore, the ball 26 can move in the individual flow path 16 again and can close the opening 20 of the valve seat 22.

Although some specific examples have been described in detail above, these are merely examples and do not limit the scope of claims. The techniques described in the claims include various modifications and modifications of the specific examples illustrated above. The technical elements described herein or in the drawings exhibit their technical usefulness alone or in combination.

10: Vacuum suction nozzle 12: Suction surface 14: Suction hole 16: Individual flow path 20: Opening 22: Valve seat 24: Rib or tapered surface 26: Ball 28: First space 30: Common flow path 40: Ball release 42: Body plate 44: Pusher 46: Check valve

Claims (2)

A vacuum suction nozzle that sucks an object
The suction surface that comes into contact with the object and
A plurality of suction holes provided on the suction surface and
A plurality of individual flow paths extending from the plurality of suction holes, and
It is provided with a common flow path connected to the plurality of individual flow paths and connected to an external vacuum circuit.
Each of the plurality of individual flow paths
A valve seat with an opening and
It has a ball that is movably accommodated between the suction hole and the valve seat, is seated on the valve seat by the flow of the individual flow path, and closes the opening of the valve seat.
The inner wall of the individual flow path is provided with a rib or a tapered surface that is located between the suction hole and the valve seat and projects inward as it approaches the valve seat.
Vacuum suction nozzle. Further equipped with a ball release movably housed in the common flow path,
The ball release
A main body plate facing the plurality of individual flow paths and
A plurality of pushers provided on the main body plate and extending toward the plurality of individual flow paths, and a plurality of pushers.
It is provided on the main body plate and has at least one check valve that prohibits the flow toward the plurality of individual flow paths and allows the flow in the opposite direction.
The vacuum suction nozzle according to claim 1.

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