Abstract:
In a suction device, a suction head is alternately connected to a negative pressure source and a positive pressure source by means of a switching valve, a light-weight workpiece is sucked by and released from the suction head. When the suction head and the positive pressure source are connected to each other by means of the switching valve to release the workpiece, a releasing pressure is instantaneously supplied to the suction head. The magnitude of the releasing pressure is set to a value equal to or less than the atmospheric pressure and set to a value which is necessary for the workpiece to drop by its own weight from the suction head.
Abstract:
Lightweight part retention apparatus is arranged on a removal tool plate. A low pressure air supply is supplied to the apparatus to induce an area of reduced pressure in a channel formed in a passage therein, the reduced pressure being formed by a jet pump action within the channel. The reduced pressure draws a part to be removed from a mold or the like into the apparatus and retains it therein until a separate device removes it and/or the air supply is interrupted. Due to the relatively low mass of the retention apparatus, the tool plate and retention apparatus, with the molded part retained therein, can then be rapidly withdrawn from the open mold to permit early closing of the mold so that a new molding cycle may begin.
Abstract:
The present invention relates to a process and a device for applying tensile forces, with no contact with solid walls, to glass sheets, in particular at high temperatures, wherein a gas or vapor is blown between the glass sheet and a wall closely approached, and parallel, to said glass sheet. Between the glass sheet and said wall a gas cushion is established, in that the sections through which the gas flows inside the air gap between the glass sheet and the wall increase on the average in the direction of streaming of the gas, so as to allow the gas speed to decrease, and a recovery in gas pressure to consequently take place. Several forms of practical embodiment of the device are disclosed.
Abstract:
A vacuum chuck apparatus operable in both gas and liquid includes a liquid-gas separating membrane which allows passage of gas molecules but prevents passage of liquid. The liquid-gas separating membrane is disposed between an inlet hole of the chuck and a manifold which is connected to a pneumatic system. The pneumatic system includes an aspirator, a compressor and a switching valve. The vacuum chuck is immersed into a liquid, compressed gas purges the liquid in the inlet hole, then the switching valve is switched to the aspirator. An object, such as a semiconductor wafer, is vacuumed quickly to the chuck, and the inlet hole is closed by the object. If a small quantity of liquid intrudes into the chuck, it is stopped by the liquid-gas separating membrane.
Abstract:
A process and apparatus for supporting crystalline wafers utilizing the sion effect of flowing gas on the crystalline wafers. An almost point-like support of the crystalline wafer is achieved. Furthermore, the invention relates to a holding tool for carrying out the process, which tool has at the center of the holding face, a point-like projection.
Abstract:
A conveying and supporting surface is provided with a plurality of coanda effect nozzles for providing a directional film of gas along the surface to support and/or convey a plurality of articles, in indefinite length web, or material along the surface. The directional coanda effect nozzles will produce a conveying film of gas and a film of gas that will produce a suction spaced from the surface to hold the articles closely adjacent the surface while at the same time produce an air bearing to prevent the articles or web material from contacting the surface.
Abstract:
A system for handling plate like objects (e.g., semiconductor wafers) includes a gas actuated fixture having a surface for releasably picking up the plate like objects (e.g., by Bernoulli effect). Means is provided for moving the pickup fixture in a plane of motion from a first to second position. Means forming a part of the pickup fixture (e.g., a selectively pressured bellows) moves the pickup surface orthogonally to the plane of motion. An air track or other conveyer for the plate like objects includes means for restraining the objects beneath the first position. Means for positioning successive locations of a carrier for the plate like objects positions the successive locations beneath the second position. In operation, the system picks up the plate like objects from the conveyer, loads them onto the carrier, then unloads them from the carrier and returns them to the conveyer, all without subjecting the objects to human contamination.