JPH055342U - Vacuum check - Google Patents

Abstract

(57) [Summary] [Object] The present invention aims at a vacuum chuck capable of accurately sucking and holding a work even if the shape of the work is different from the arrangement pattern of the suction holes. [Structure] A communication hole 5 communicating with the vacuum chamber 1 and a suction hole 6 for adsorption are provided in the valve chamber 4, and a ball valve 7 is built in the valve chamber 4. In the communication hole 5 of the valve chamber 4, a valve seat 8 is formed at a position higher than the ball valve receiving portion of the valve chamber 4, and when the suction hole 6 is not covered with the work W, the suction air flow causes the ball valve 7 to move. It rides on the valve seat 8 and closes the communication hole 5.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a vacuum chuck used for chucking a work in a machine tool or the like.

[0002]

[Prior Art]

 Since the conventional vacuum chuck as described above has only a large number of suction holes communicating with the vacuum chamber on the surface of the suction plate, when the arrangement pattern of the suction holes and the shape of the work do not match. There was a problem that a large amount of air flowing in from the suction holes communicating with the outside air reduced the degree of vacuum and lost the adsorption power.

[0003]

[Problems to be solved by the device]

 The present invention has been completed for the purpose of solving the above-mentioned problems and aiming at a vacuum chuck capable of accurately sucking and holding a workpiece even when the arrangement pattern of the suction holes and the shape of the workpiece do not match.

[0004]

[Means for Solving the Problems]

 The present invention, which has been made to solve the above problems, forms a valve chamber having a communication hole communicating with a vacuum chamber on the lower surface of a suction plate having a suction hole, and a ball valve is built in this valve chamber. The valve seat is formed in the communication hole of the valve chamber at a position higher than the ball valve receiving portion of the valve bottom.

[0005]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the drawings. Reference numeral 1 denotes a vacuum chamber, and a top plate portion 2 of the vacuum chamber 1 is provided with a large number of valve chambers 4 partitioned by suction plates 3, and the valve chambers 4 have communication holes communicating with the vacuum chamber 1. 5 and a suction hole 6 communicating with the outside are provided.

Reference numeral 7 is a ball valve which is freely movably incorporated in the valve chamber 4, and 8 is a valve seat which is fitted into the communication hole 5 of the valve chamber 4 and has elasticity like a rubber tube. Is projected so as to be higher than the ball valve receiving portion of the valve chamber 4, and normally the ball valve 7 does not block the communication hole 5.

[0007]

[Action]

 As shown in FIG. 1, when the work W is placed on the suction hole 6 of the suction plate 3 and the suction hole 6 is blocked by the work W as shown in FIG. Since the air in 6 is sucked and exhausted into the vacuum chamber 1 through the communication hole 5, a negative pressure acts on the work W and is sucked and held on the suction plate 3.

Further, when adsorbing a work W that does not match the arrangement pattern of the suction holes 6 of the suction plate 3, as shown in FIG. 2, a large amount of air flowing in from the suction holes 6 on which the work W is not placed is admitted. Will be sucked into the vacuum chamber 1 through the communication hole 5 of the valve chamber 4. Therefore, the freely movable ball valve 7 contained in the valve chamber 4 is sucked by the elastic valve seat 8 by the suction airflow passing through the communication hole 5.

The ball valve 7 sucked by this suction airflow is attracted to the valve seat 8 attached to the communication hole 5 at a position higher than the ball valve receiving portion of the valve chamber 4, and its upper end surface Since the communication hole 5 is closed by riding on the above, the vacuum chamber 1 and the outside are shut off and the inflow of air is stopped. Therefore, the vacuum degree of the vacuum chamber 1 is maintained, and the suction force for the work W is not lost. When the work W is adsorbed in the suction hole 6, the ball valve 7 is not sucked and rides on the valve seat 8 because the suction airflow in the valve chamber 4 is weak.

In addition, in the above-described embodiment, a large number of valve chambers 4 are formed in the top plate portion 2 of the vacuum chamber 1. However, in a special case, the valve chamber 4 may be a single valve chamber 4. Is. In the embodiment shown in FIG. 1, the valve bottom of the valve chamber 4 has an inverted conical shape, and the valve seat 8 is projected from the inclined surface of the inverted cone, and the upper end surface of the valve seat 8 is cut off obliquely. The valve 7 prevents the valve seat 8 from being inadvertently closed, and the ball valve 7 drops from the valve seat 8 immediately after the suction hole 6 is blocked by the held body W. As shown, the valve seat 8 may be projected from the horizontal valve bottom.

Further, in the embodiment shown in FIG. 4, it is assumed that the valve bottom has a conical shape and the valve seat 8 is projected from the top thereof, so that the ball valve 7 inadvertently closes the valve seat 8 due to vibration. Although it is prevented, the shape of the valve bottom is not particularly limited as long as the ball valve 7 is prevented from riding on the valve seat 8 at normal times. Further, the valve seat 8 is required to be elastic enough to make the ball valve 7 suction-adhere, and strong enough to prevent the valve seat 8 from being crushed by the negative pressure when the ball valve 7 is adsorbed.

Further, in the embodiment shown in FIGS. 5 and 6, the valve seat 8 having elasticity is not fitted in the communication hole 5, but the tip of the communication hole 5 of the valve chamber 4 is used as the valve seat 8. By providing the seat 8 at a position higher than the ball valve receiving portion of the valve chamber 4 and using the ball valve 7 as an elastic body, it is possible to obtain the same shielding effect as when the valve seat 8 having elasticity is used.

[0013]

[Effect of the device]

 As is apparent from the above description, the present invention provides a valve chamber having a suction hole for suction and a communication hole communicating with the vacuum chamber in the top plate portion of the vacuum chamber, and a ball valve is built in the valve chamber. Since the valve seat, which is located higher than the ball valve receiving portion of the valve chamber, is formed in the communication hole of the valve chamber, the shape of the workpiece differs from the arrangement pattern of the suction holes and the suction holes are opened to the outside. In this case, the ball valve rides on the valve seat by the suction air flow and closes the communication hole, so that the vacuum level is prevented from lowering and the suction force can always be maintained accurately. Therefore, the present invention has an extremely great practical value as a vacuum chuck that solves the conventional problems.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a different state.

FIG. 3 is a cross-sectional view showing an embodiment in which the valve bottom of the valve chamber is horizontal.

FIG. 4 is a cross-sectional view showing an embodiment in which a valve bottom of a valve chamber has a conical shape.

FIG. 5 is a cross-sectional view showing an embodiment in which a ball valve is an elastic body with a tip of a communication hole as a valve seat.

FIG. 6 is a sectional view showing another embodiment in which the tip of the communication hole is a valve seat and the ball valve is an elastic body.

[Explanation of symbols]

 1 vacuum chamber 3 adsorption plate 4 valve chamber 5 communication hole 6 suction hole 7 ball valve 8 valve seat W work

Claims (1)

[Claims for utility model registration] [Claim 1] A valve chamber (4) having a communication hole (5) communicating with the vacuum chamber (1) on the lower surface of a suction plate (3) having a suction hole (6) To form a ball valve (7) in this valve chamber (4),
A vacuum chuck characterized in that a valve seat (8) is formed in a communication hole (5) of the valve chamber (4) at a position higher than a ball valve receiving portion of the valve bottom.