US2396042A - Pressing apparatus - Google Patents

Description

March 5, 1946. B; A. EVANS PRESS ING APPARATUS Filed Nov. 30, 1944 jEi'j 527215;? z/Efis Patented Mar. 5, 1946 UNITED STATES PATENT OFFICE.

PRESSING APPARATUS Benjamin A. Evans, Cuyahoga Falls, Ohio, assign or to TheB. F. Goodrich Company, New York, N. Y., a corporation of New York Application November 30, 1944, Serial No. 565,897

4 Claims.

This invention relates to pressing apparatus such as platen presses and is especially useful where presses having platens of great area are to be used in vulcanizin sheet material such as ber and other materials stick to the platens and become permanently attached thereto while some materials employed corrode the platen, requiring frequent cleaning and polishing of the platen faces. As the platens are often of great area it has been customary to employ portable sanding and polishing apparatus to clean and polish the platens in place. Frequent cleaning and polishing has sometimes resulted in departure from a true surface so that the belts or other articles vulcanized therebetween have been of non-uniform thickness.

As belts and other sheet material vulcanized in presses must depend for their surface characteristics upon the characteristics of the surfaces against which they are vulcanized, a highly finished surface Will' produce a highly finished article, whereas an irregular or dirty surface will produce an article having an inferior surface.

Heretofore it has been necesary to remove the platens from a press at frequent intervals and return them to a machine shop for resurfacin with loss of press time, and, with repeated machining, considerable loss of strength of the platens.

The present invention has for one of its objects to avoid the foregoing and other difficulties.

Other objects are to provide a removable platen surface, to provide reduction of corrosion, to provide a more highly finished vulcanized article, and to provide for convenience of mold maintenance.

These and other objects will appear from the following description and the accompanying drawing.

Of the drawing,

Fig. 1 is a side elevation of a hydraulic belt press constructed in. accordance with and embodying the invention, portions being broken away,

Fig. 2 is a cross-sectional view thereof taken on line 2-2 of Fig. 1,

Fig. 3 is a detail view of a modified form of the invention, parts being broken away.

Referring to the drawing, the numeral l0 designates the upper or fixed 'platen of a hydraulic belt press supported by tension rods H. The moveable or lower platen I 2 rests upon a series of rams I3 each fitted in a cylinder M, the rams being operated in unison by admission of fluid under pressure simultaneously to all of the cylinders and lowered by simultaneous draining of all the cylinders. The lower platen is guided in its vertical movement by the tension rods H. The platens are chambered, as at l5, I6 for circulation of heating fluid, such as steam, and are .connected by swing joints l1, 18 to stationary piping (not shown) whereby steam or other heating fluid is circulated through the platens at vulcanizing temperature.

For providing a highly polished corrosion-resistant surface over the moveable platen, a pair of laterally spaced-apart brackets 20 are fixed to one end of the platen and have aligned bearings for supporting a horizontal winding shaft 2|. A drum 22 is fixed to the shaft. A ratchet wheel 23 is also fixed to the shaft in position to engage a pawl 24 pivoted upon one of the brackets 20. At the opposite end of the platen, similar laterally spaced brackets 25 support a horizontal shaft 26 having a drum 2! and a ratchet wheel 28 fixed thereto.

A band 32 of highly polished corrosion-resistant metal, such as stainless steel, has one end secured, as by screws or clamps to the surface of the drum 22 and the other end secured by similar means to the drum 2'! and extends from one drum to the other across the face of the platen to provide a removable vulcanizing surface thereover. The shafts 2| and 26 are squared at their ends to receive a crank handle 30 which is interchangeable, the crank havin a squared opening to engage the shaft ends. The ratchet wheels 23, 28 are of opposite hand and so arranged that the pawl 24 normally prevents rotation of drum 2| in a counter-clockwise direction and pawl 3| which engages ratchet wheel 28 normally prevents rotation of drum 21in a clockwise direction. Either pawl may be displaced from its nor. mal position where it engages a ratchet by a handle fixed thereto. The arrangement is such that themetal band may be tensioned by rotating either of the shafts with the pawls engaging the ratchets and will be held in tensional relation by the ratchets and pawls.

The band 32 may be merely long enough to extend from one drum to the other, in which case the drums are used merely to tension the band, or the band. may be several times such length in which case the excess length is stored on the drums and the band may be shifted from time to time to present successive portions thereof for use between the press platens. Where the band is only slightly more than the length of the platens, one of the winding drums may be dis-.

32 has its end clamped between the clamp bars by the bolt 37. 1

A similar band 38 of polished corrosion-resistant metal is secured over the face of the upper platen In, its one end being secured either by a tensioning drum 39 having a ratchet wheel 40 held against turning in one direction by a pawl 4| as'shown in Fig. 1 or by clamp means such as-that of Fig. 3. The other end of the band 38 is secured to a drum 42 at the opposite end of the press. Drum 42 is fixed to a shaft 43 having a squared rod for receiving a crank 44. A ratchet 45 secured to shaft 43 is prevented from rotating in one direction by a pawl 46 pivotally secured to the platen and having a handle 41 for displacing it when the drum is to be turned in the normally locked direction.

In use, the bands of corrosion-resistant metal are tensioned across the face of the platens preferably after the press platens have been heated to the desired temperature. The belt or other sheet to be vulcanized is then drawn through the press and the lower platen is raised to press the sheet between the metal bands. Should the bands become dirty, they may be quickly removed from the press and replaced by others, or, where the bands are longer than the press, they may be wound from one set of drums to the other to present a clean surface for use and then tensioned. When a band becomes soiled, it may be removed and cleaned by passing it through cleaning baths or polishing machines without delaying operation of the press.

Variations may be made withoutdeparting from the scope of the invention as it is defined by the following claims.

I claim:

' 1. Pressing apparatus comprising a pressing member, a removable pressing sheet of corrosion-resistant metal upon a face thereof, and means on said pressing member for tensioning said sheet in the direction of said face.

2. Pressing apparatus comprising a pressing member, a removable pressing sheet of stainless steel upon a face thereof, and means on said pressing member for tensioning said sheet in the direction of said face.

3. Pressing apparatus comprising a pressing member, a removable pressing sheet of corrosion-resistant metal upon a face thereof, means for securing one end of the sheet to the pressing member, and a tensioning drum at the opposite end of the member for securing the opposite end of said sheet and presenting a tensioned portion thereof across said member.

4. Pressing apparatus comprising a press platen. winding drums at opposite ends of the platen, a pressing sheet of corrosion-resistant metal having a length greater than said platen. the ends of said sheet being secured about said drums. means for rotating said drums to tension said sheet across said platen. and means for looking saiddrums against rotation in a direction tending to reduce the tension of said sheet.

BENJAMIN A. EVANS.

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