US2575734A

US2575734A - Press

Info

Publication number: US2575734A
Application number: US794613A
Authority: US
Inventors: Earl L Schulman
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1947-12-30
Filing date: 1947-12-30
Publication date: 1951-11-20
Anticipated expiration: 1968-11-20

Description

Patented Nov. 20, 1951 PRESS Earl L. Schulman, Swissvale, Pa., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application December 30, 1947, Serial No. 794,613

3 Claims.

This invention relates generally to presses and more particularly to a press for consolidating materials.

An object of this invention is to provide, in a press having a pressure chamber, for sealing the pressure chamber of the press during a pressing operation.

A further object of the invention is to provide, in a press having a pressure chamber formed by an elastic diaphragm and a press head, for sealing the elastic diaphragm to the press head during a pressing operation.

Other objects of the invention will in part be obvious and will in part appear hereinafter. For a better understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in conjunction With the accompanying drawing, in which:

Figure 1 is a view in cross section of an apparatus embodying the features of the invention; and

Fig. 2 is a View in cross section of another embodiment of this invention.

Referring to Fig. 1, there is illustrated a press I comprising a pair of platens I2 and I4 which are provided with means (not shown) for moving them relative to each other into cooperating pressing relationship.

The platen I2 is provided with a depending rim member it. As illustrated, an impervious flexible diaphragm 20 is disposed across and in spaced relation to, the face II of the platen I2 and in seating engagement with the rim member I8 to form a pressure chamber or space IG. In the embodiment illustrated, the flexible diaphragm 2B is secured to the sides of the platen I2 by fastening means 22 which in this instance comprises a metal band. In practice, the flexible diaphragm 2G is preferably an elastomer such as rubber or a silicon polymer capable of withstanding elevated temperatures.

A conduit or aperture 24 is disposed in the platen I2 for introducing steam or hot water or other suitable fluid under pressure into the space I6. Cooling water may be introduced in the space II; by the conduit 26 and vented through the conduit 28.

The platen I l includes a continuous channel 30 disposed in the pressing face 3| adjacent to the outer edge thereof and conforms to the configuration of the depending rim member I8 disposed in the face of platen I2.

Although the rim member I8 has been described hereinbefore as being adjacent to the outer edge of platen I2, it will be understood that the projecting member I8 may be disposed in a predetermined path on the face of platen I2 .to form a cavity it of any required configuration in which case the channel 3!) is disposed in platen I4 in a configuration conforming to the path of the member I8.

A flexiblev tubular member 32 is disposed in the channel 30 and connected by conduit 33 extending through the platen I4 to a source of fluid supply (not shown) for supplying fluid under pressure to the member 32. A heating means is provided in the platen I4 such as coils or tubes 34 through which a heating fluid may be circulated to secure predetermined temperatures.

The operation of the apparatus will be described in connection with a specific application, which is the production of bonded mica sheets by the method disclosed in my copending application Serial No. 696.601, filed September 12, 1946, now Patent No. 2,524,932, but it will be understood that the description of this specific application is given in an illustrative and not in a limiting sense.

In operation, a layer 36 of mica flakes and an uncured flowable binder distributed through the mica flakes is placed on the platen I4. The platens I2 and I4 are then actuated into coopcrating pressing relationship whereby the flexible diaphragm 20 contacts the layer 36 of mica and binder and the platen I4 contacts the por-' tion of the flexible diaphragm 20 disposed over the depending member I8 along a continuous predetermined path.

The channel 30 is disposed as hereinbefore described in the platen l4 in such relation to the depending member I8 that when the platens I2 and I4 are in pressing relationship, the portion of the flexible diaphragm 20 disposed over the depending member I8 covers the continuous channel 30 throughout its length.

While the platens I2 and I4 are being held in pressing relationship, a fluid is admitted under pressure to the interior of the tubular member 32 to expand it to exert force against the adjacent portion of the flexible diaphragm 26 thereby forcing the diaphragm 20 into sealing engagement with the depending member I8.

Steam or hot water is then admitted under pressure through the conduit 24 into the space It, thereby forcing the flexible diaphragm 23 against the surface of the mica layer 36. It will be understood that the pressure applied to the tubular member 32 should be substantially greater than the pressure in the space I6 to effect a satisfactory sealing engagement between the flexible member I6 and the depending member l8. Inasmuch as the tubular member 32 forces the flexible diaphragm 20 into sealing contact with the depending member I8 on a continuous path of a predetermined configuration, the fluid applied to cavity I6 is thereby prevented from escaping from between the flexible member 26 and the depending member I8. Heat from the steam or hot water in the space It is transferred through the flexible diaphragm 29 to the layer 36 of mica and binder and simultaneously steam or hot water may be admitted to the tubes 34 in the platen 14 for heating the layer of micaand binder from the underside.

In the specific application of the apparatus to the manufacture of bonded mica sheets, it is preferred to admit steam at a pressure of between about 20 and 100 pounds per square inch to the space 16 to accomplish the consolidation of the mica and binder. The pressure applied to the flexible tube 32 should in every case be greater than the pressure in the space IE, to effect satisfactory sealing between the flexible diaphragm 26 and the depending or projecting member is as hereinbefore described.

At the end of the predetermined pressing period, the pressure in cavity I6 is released and cooling water may be admitted through conduit 26 and vented through conduit 28, thereby cool- .4 tinuous projecting portion disposed on the face of one of the platens in a predetermined manner to form an enclosed area thereon, an impervious -elastie diaphragm disposed in seating relationship on the continuous projecting portion across the enclosed area to form a space between the elastic diaphragm and the one platen, means for ing the mica sheet 36. When the sheet has cooled sufliciently, the cooling water is shut off, the

pressure applied to the tubular member 32 is re- 1 leased and the press head separated for removal of the consolidated mica sheet 36.

Fig. 2 illustrates another embodiment of this of the platen face I I' by a clamping ring 38. The

clamping ring 38 is held in position with respect to the platen l2 by means of screws 39 disposed in spaced relation along the ring 38. A conduit 24 is disposed in the platen l2 for the admission of fluid to transmit pressure to the flexible member and the platen 12.

In the embodiment of Fig. 2, projecting members 40 and 42 are disposed in spaced relation to each other on and carried by the face 3| of the platen M in a predetermined path to form a cavity 44 of predetermined configuration within the confines of the projecting member 42; The projecting member 40 is positioned on the face 3| of platen 14 in such relation to the position of clamping ring 38 disposed on platen l2 as to permit engagement of the projecting members lie and 42 with the flexible diaphragm 20 when the platens are in pressing relationship. The projecting members 60 and 42 are disposed in spaced relation to one another for cooperating to form a continuous channel 26 therebetween for receiving the flexible tubular member 32.

In operation a layer 36 of mica flakes and uncured flowable binder is placed in the cavity 64, and the platens l2 and 14 are then actuated into cooperating pressing relationship, whereby the projecting members and 42 contact the flexible diaphragm 20. The pressure thereafter applied to the interior of the tubular member 32 causes expansion of the tubular member against the flexible diaphragm 20', forcing the flexible diaphragm into sealing relationship with the platen face ll along a continuous line contact of predetermined configuration, to prevent loss of pressure from between the flexible member 20' and the platen face I i.

It will be understood that changes may be made in the structure of the apparatu disclosed without departing from the spirit of the invention.

I claim as my invention:

1. A press comprising, a pair of relatively movable aligned platens having opposed faces, a conapplying fluid pressure to the space, a continuous channel disposed in the face of the other platen in alignment with the continuous projecting portion of said one platen, a flexible tube disposed in the channel, means for appliyng pressure to the interior of the flexible tube when the platen faces are in pressing relationship whereby the flexible tube contacts the elastic diaphragm to force the diaphragm into sealing contact with the projecting portion of the one platen to prevent loss of fluid pressure fromsaid space.

2. A press comprising, a pair of relatively movable platen having opposed faces disposed for movement into cooperating pressing relationship, a projecting portion disposed on the face of one of the platens adjacent to the outer. edge and substantially conforming to the confluration thereof, an impervious elastic diaphragm disposed over the face of the oneplaten in seating relationship on the projecting portion to form aspace between the elastic diaphragm and the one platen,

mean for applying fluid pressure to the space, a

continuous channel formed in the other platen adjacent to the outer edge thereof and conforming to the configuration of the projecting portion on said one platen, a flexible tube disposed in the channel, means for applying pressure to the interior of the flexible tube when the platen faces are in pressing relationship whereby the flexible tube contacts the elastic diaphragm and forces it into sealing contact with the projecting portion of said one platen to prevent loss of fluid pressure from said space.

3. In a press, the combination comprising, a pair of relatively movable platens having opposed faces disposed for movement into cooperating pressing relationship, a continuous projecting portion carried by one of the platens to form a cavity of predetermined configuration on the face thereof, an impervious elastic diaphragm disposed across the face of the one platen in seating engagement with the projecting portion to form a space between the elastic diaphragm and the one platen, means for applying fluid pressure to the space, a continuous channel disposed in the face of the other platen to conform to the configuration of the continuous projecting portion, a flexible tube disposed in the channel, means for applying pressure to the interior of the flexible tube greater than the pressure applied to said space whereby the flexible tube contacts the elastic diaphragm when the platen faces are in pressing relationship to force the elastic diaphragm into sealing contact with the projecting portion of the one platen to prevent loss of fluid pressure from said space.

EARL L. SCHULMAN.

REFERENCES CITED The following references are of record in the flle of this patent:

UNITED STATES PATENTS Number Name Date 1,146,413 Edison July 13, 1915 1,260,002 Lanhoffer Mar. 19, 1918 1,806,861 Owen May 26, 1931 2,288,356 Humphrey June 30, 1942