JPH074125Y2 - Vacuum chuck - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum chuck used for chucking a work in a machine tool or the like.

[0002]

2. Description of the Related Art Since the conventional vacuum chuck as described above is provided with only a large number of suction holes communicating with the vacuum chamber on the surface of the suction plate, the arrangement pattern of the suction holes and the shape of the workpiece are different. If they do not match, there is a problem that a large amount of air flowing in from the suction holes communicating with the outside air reduces the degree of vacuum and loses the suction force.

[0003]

SUMMARY OF THE INVENTION The present invention solves the above problems and provides a vacuum chuck capable of accurately sucking and holding a work even when the arrangement pattern of the suction holes and the shape of the work do not match. It was completed for the purpose.

[0004]

SUMMARY OF THE INVENTION 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. A ball valve is built in the valve chamber, and a valve seat is formed in a communication hole of the valve chamber at a position higher than a ball valve receiving portion of the valve bottom.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings. Reference numeral 1 denotes a vacuum chamber, 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 that communicates with the outside are provided.

Reference numeral 7 denotes a ball valve which is freely movably incorporated in the valve chamber 4, and 8 denotes a valve seat which is elastic like a rubber tube and is fitted in the communication hole 5 of the valve chamber 4, and the valve seat 8 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]

With this structure, the work W is placed on the suction hole 6 of the suction plate 3 as shown in FIG.
When the work W is closed by the work W, the air in the valve chamber 4 and the suction hole 6 is sucked and exhausted into the vacuum chamber 1 through the communication hole 5, so that a negative pressure acts on the work W to suck it on the suction plate 3. Retained.

Further, when sucking 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 sucked up to the valve seat 8 attached to the communication hole 5 so as to be at a position higher than the ball valve receiving portion of the valve chamber 4, and the upper end surface thereof. Because the communication hole 5 is closed by riding on the vehicle, the vacuum chamber 1 and the outside are shut off and the inflow of air is stopped.
Therefore, the degree of vacuum 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 suction airflow in the valve chamber 4 is weak, so that the ball valve 7 is not sucked and does not ride on the valve seat 8.

In the above 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 there. In the embodiment shown in FIG. 1, the valve bottom of the valve chamber 4 has an inverted conical shape. Does not inadvertently close the valve seat 8, and the ball valve 7 drops from the valve seat 8 as soon as the suction hole 6 is closed by the held body W, as shown in FIG. Thus, the valve seat 8 may be projected from the horizontal valve bottom.

In the embodiment shown in FIG. 4, the valve bottom is conical and the valve seat 8 is projected from the top.
The ball valve 7 prevents the ball valve 7 from inadvertently closing the valve seat 8 due to vibration, but the shape of the valve bottom is particularly limited if the ball valve 7 is prevented from riding on the valve seat 8 at normal times. is not. 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. When 8 is set to a position higher than the ball valve receiving portion of the valve chamber 4 and the ball valve 7 is made of an elastic body, the same shielding effect as when the elastic valve seat 8 is used can be obtained.

[0013]

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 on the top plate of the vacuum chamber, and the valve chamber has a ball chamber. Since the valve is built in and a valve seat that is higher than the ball valve receiving part of the valve chamber is formed in the communication hole of the valve chamber, the shape of the workpiece differs from the suction hole arrangement pattern and the suction hole is external. When the valve is opened, the ball valve rides on the valve seat by the suction airflow to close the communication hole, prevent the vacuum degree from decreasing, and always maintain the suction force 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 cross-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 cross-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)

[Scope of utility model registration request] 1. A valve chamber (4) having a communication hole (5) communicating with the vacuum chamber (1) is formed on the lower surface of an adsorption plate (3) having a suction hole (6), and the valve chamber (4) is formed. In addition to incorporating the ball valve (7) in 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.