JP2001322080A - Contactless holding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To confirm the state of a contactless holding device positively holding a workpiece. SOLUTION: This contactless holding device is constituted by forming the internal space of an arm-like base body E as a cushion chamber, providing the upper part of the cushion chamber 4 with a nozzle 2 for blowing high speed air P, forming a holding face 4 at a face, opposed to a workpiece, of a peripheral wall 1, and providing the peripheral wall 1 with a pressure detecting tube 5 piercing the cushion chamber 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact holding device used as a hand of a transfer device such as a robot for transferring a work such as a semiconductor wafer in a non-contact state.

[0002]

2. Description of the Related Art Japanese Patent Laid-Open No. Sho 62-105831 discloses a non-contact holding device for suspending a work in a non-contact state by blowing air.

When this device is mounted on a robot and a work is transported, there is no means for confirming that the device has held the work. Therefore, when the device is close to the work, air can be held for a certain period of time. After erupting, the workpiece is regarded as holding and moving.

[0004] For this reason, the non-contact suction device may move in a state where air is blown out even though the work is not held, thereby causing harm such as lifting up dust, blowing out peripheral equipment, and breaking. However, even if the workpiece is detached, it cannot be detected, and the peripheral device is damaged.

[0005] Further, since the suction waiting time is provided, there is a drawback that the tact time is lengthened and the working efficiency is deteriorated.

[0006]

The problem to be solved is that it cannot be confirmed that the non-contact suction device ejects air to hold the workpiece in a suspended state.

[0007]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, typical ones are briefly described as follows.

In other words, a non-contact suction device for generating a negative pressure in a gap between the opposing work by blowing air and holding the work suspended in a non-contact state is provided with a penetrating pressure detecting tube. Non-contact holding device characterized.

According to the present invention, when the air ejected from the nozzle toward the work passes through the narrow gap between the holding surface and the work, it becomes a high-speed airflow and a large negative pressure is applied inside the non-contact suction device and the gap. Therefore, the workpiece can be held by detecting the negative pressure.

[0010]

Embodiment 1 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a side sectional view of a non-contact holding device A according to an embodiment of the present invention.

As shown in FIG. 1, a peripheral wall 1 of an arm-shaped base E is provided.
A holding surface 4 facing the work 6 is formed at the lower end of the peripheral wall 1.
Is defined as a cushion room 3 and the cushion room 3
A non-contact suction device D is formed by providing a nozzle 1 for ejecting a high-speed airflow P above the space.

A pressure detecting pipe 5 is provided to penetrate the cushion chamber 3 from the side surface of the peripheral wall 1. The pressure detecting pipe 5 is connected to a pressure detector 7 through a pipe 8, and the pressure in the cushion chamber 3 is detected by the pressure detector 7. To form a non-contact holding device A configured to be detectable.

When the distance h between the work 6 facing the holding surface 4 and the work 6 increases, the high-speed airflow P ejected from the nozzle 2 passes through the cushion chamber 3 and the gap between the work 6 and the holding surface 4 so that a cushion Room 3 has an ejector effect
Further, a negative pressure is generated in the gap between the work 6 and the holding surface 4 by the Bernoulli effect, and the work 6 is sucked and held in a non-contact state.

At this time, the pressure inside the cushion chamber 3 is detected by the pressure detector 7 through the pressure detecting tube 5, and by detecting a negative pressure equal to or more than a predetermined value capable of suspending and holding the work 6, the suspension of the work 6 is detected. It is possible to make a holding confirmation.

The attachment and detachment of the work 6 during the transfer can be determined by sensing the pressure rise in the cushion chamber 3.

FIG. 2 shows a method for detecting a negative pressure generated by the Bernoulli effect in a gap between the work 6 and the holding surface 4 by providing a pressure detecting tube 5 on the holding surface 4 facing the work 6. ing.

[0018]

FIG. 3 is a side sectional view showing another embodiment of the present invention.

In this embodiment, a non-contact holding device C is formed by attaching a distance sensor 9 for detecting a distance h to the workpiece 6 to the non-contact suction tool D.

By ejecting the high-speed air P toward the work 6, the work 6 is sucked into the non-contact holding device C.

At this time, the holding of the work 6 can be confirmed by detecting the distance h from the work 6 by the distance sensor 9 and detecting that the suspension holding distance has been reached.

It goes without saying that the present invention can be applied not only to the non-contact suction device D but also to a suction device that generates a negative pressure by ejecting air to suction-hold a work in a non-contact state, a Bernoulli chuck, and the like.

[0023]

The effects obtained by typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) Since the holding of the work is confirmed by the negative pressure generated inside the non-contact holding device, the reliability is high.

(2) The working speed is improved.

(3) Since the non-contact holding device does not move without holding the work, there is no dust and no contamination of the surrounding environment.

(4) Even when the work is detached and attached, the work is instantly determined, so that the work can be immediately stopped, and the surrounding environment is not harmed.

[Brief description of the drawings]

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

FIG. 2 is a side sectional view of another embodiment of the present invention.

FIG. 3 is a side sectional view of another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Peripheral wall 2 Nozzle 3 Cushion room 4 Holding surface 5 Pressure detecting tube 6 Work 7 Pressure detector 8 Pipe line 9 Distance sensor A, B, C Non-contact holding device D Non-contact suction device E Base P High-speed air

Claims (2)

[Claims] 1. A non-contact suction device for generating a negative pressure in a gap between an opposing work by ejecting air and suspending the work in a non-contact state, and having a penetrating pressure detection tube provided therein. Non-contact holding device characterized. 2. A non-contact holding device, wherein a distance sensor for detecting a distance from a workpiece is attached to the non-contact suction device according to claim 1.