US1270559A - Clutch-facing. - Google Patents

Description

No Drawing.

.of unwoven felted short ii UNITED STATES PATENT OFFICE.

SUMNER SIMPSON, 0F BBIDGEPOBT, CONNECTICUT, ASSIGNOR TO THERAYBESTOB 00., OF BRIDGEPORT, CONNECTICUT, A CORPORATION OF CONNECTICUT.

CLUTCH-FACING:-

l atented June 25, 1918.

1,270,559. Specification of Letters Patent.

Application illed September 19, 1917. Serial 80.182332.

To all whom it may concern Be it known that I, SUMNER Smrson, a citizen of the United States, residing in the city" of Bridgeport, county of Fairfield, and

,State of Connecticut, have invented certain character referred to, which is uniform in character and uniform in density throughout its wearing surface and to a substantial depth of the latter; to provide a product, the essential body portion of which may be made of short asbestos fiber united through the medium of a comminuted binder; to roduce a product of the above character vg 'ich can be formed to micrometer measurements, bothas regards its width and thickness; to provide a roduct havin the required co-efficient o friction, which has a maximum wearin resistance and is-capable of withstanding igh temperatures without physical or chemical change; toprovide a product which can be made of unspun short fiber, to. which may be added the dust or screenings of said fiber, united and held into i a compact and relatively solid mass, substantially by the binding action of a material, eommlnuted or granular when dry; to

provide a preformed asbestos or'other suitable fibrous sheet which ma' beformed out r and out of which the facings' may be stamped or cut either before or after saturation of the sheet with the binder; to provide a process of makmg the above, product which eliminates the expensive and numerous operations necessary in making a woven facing and which p rmits of the used the cheapest portion of the fiber, which forms a product havin a uniform character and density, not pose: 1e in the fibrous facings of the prior art to provide a process in which the material l ft after cutting or stamping out the facings can be re-treatcd to make a new sheet, thus reducing the waste material to a minimum; and indgeneral to rovide an improved product an process 0 the character referred to.

In friction facin s, for motor vehicles and the like, the fol owin are desirable, if not essential, characteristics which should be inherent in a good friction facing.

1. The co-eflicient of friction should be sufliciently high to meet all requirements.

2. The facing should have a high wear resistin and heat resisting ability.

3. he facing should be of uniform character and density so that even if the exposed surface wears away, there will be at'all times a uniform wearing surface.

4. The facing should be as free as possible from fibers which serve only as binders and are not themselves capable of standing abrasion or heat such as cotton, hemp or sisal fibers and paper.

5.' It is desirable to use as many short fibers as possible for the reason that the long fibers are relatively expensive.

6. The margin of profit makes it exceed ingly advantageous to have the process as economical and sim 1e as ossible.

7. The waste stoc shou d be reduced to a minimum.

8. The facing should be a tough, compact mass, free from any tendency to cause a siparation of its component parts and free 0 any tendency to revel. v

9. The facin should be capable of being punched or rilled and countersunk for rivet holes without destroying its elliciency.

Asbestos from the mine run consists of relatively long fibers, known. in the art as crude asbestos and relatively short fibers, known in the art as fiber asbestos. The

crude asbestos is the only portion that can be utilized for spinning and weaving; the fiber asbestos cannot be used for such purpose andaccordingly .low grade fiber asbestos has never been utilize in the manufacture of woven clutch facing. Heretofore no asbestos clutch facing has been successfully made except from wovenfiber.

By means of the present invention, the low de asbestos fibers or short fibers can be utilized to form the essential body portion of the clutch facing. as heretofore stated. These fibers after being. felted are anently'united into a compact uniform mass 110.- A

by means of a comminuted binder carried 7 machine and formed into laminated sheets this sheetof abnormal width, :1 large left from w ich' durin the process of manufacture in a suitable hquid vehicle.

One illustration of the manner in which the process ma be carried out is'as follows: The asbestos her or low grade short fiber as it comes from the mine 1s first ground in a suitable grinding machine or crusher.

This ground material is then put into a heater, mixed 'with water or ot er liquid solution and beaten into a pulp. The wet pulp is then delivered to a paper making of suitable width and thickness. From there the sheet passes through suitable presses anddriers.

Preferably, this sheet is of suflicient width to permit of five or more clutch facings to be stamped ,or cut out of its width, although the sheet may be made of any width ultable for meeting the particular req irements. Either before or during the operation of cutting the sheet is pressed to proper sheets. Where clutch facmgs of the ring type is to be made, they can be stamped or cut out of the body of the sheet form ng an endless annular or ring member. Bymaking these clutch facings in the form of an endless ring, the diflicul't-ies or objections incident to ajointed woven ring are obviated. Clutch facings of the cone type can also be formed from the sheet by cuttin out segments to-the radius of the cone an then forming them into proper shape. Where endless ring shaped faclngs are cut out of art of the sheet is necessaril no, further rings can be ormed. This otherwise waste material is saved by putting it back into the grinder and beate'rand runni it throughthe process as a new batch. e clutch facings are next impregnated or saturated in suitable dipping tanks with a binder. This binder may consist of either a suitable vegetable oil or gum, or mineral oil and gum, or bitumens, or a combination of the same, the comminuted solid matter T e saturated or impregnated material is then ut into a drying oven, which may be heate b closed steam coils or otherwise preferab y to a temperature not in excess 0 200 R, which drying step drives out-the solvent. .After treating the'product is fit into a curing oven, where it is subjec a higher heat, for example, from 250 to 500 'F., more or less. This step gives the necessar hardness to the fabric or facing.

e invention is not limited to the details of product and process here described, except as set forth in the appended claims.

I claim as my invention:

1. A clutch facing'having a wearing surface of uniform character and density throughout a substantial depth, the essential body portion of said wearing surface being formed of unwoven felted short asbestos fiber, and a comminuted adhesive binder permanently uniting the fiber into a solid compact mass.

2. A friction facing having a comsressed wearin surface,- of uniform 'ensity throng out a substantial depth, the essential body. portion of said wearin surface being formed of unwov'en felted ber havin a high abrasive resist character an a binder permanently'umting the fiber.

3. A clutch facin blank of abnormal width, the'essential ody portion of which consists of a sheet of unwoven felted asbestOS fiber adapted to be formed into a plurality of :Eacmgs and capable of being per;-

-' manently united into a solid compact mass by intimately uniting the fiber'with a comminuted adhesive binder.

SUMNER smrson.

DISCLAIMER.

. 1,270,559.Sumner Simpson, 'Bridgeport, Coim. Curr-cu F AGING. Patent dated June 25, 1918. Disclaimer filed October 3, 1923, by the asignae, The Raybestoa Company. v v Hereby disclaim the article defined by said claim 2, exgept when such article is in the form of a relatively thin disk, or plpte, or strip, a side, or relatively wide fgoe, of which receives the wear, and wherein during its use no binding medium addilii'onal'to that used in its manufactur'e need be applied for preventing material disintegmtion thereof.

[OM01 Gazette October 8:, 1983.]