US3168388A

US3168388A - Apparatus for producing glass fibers

Info

Publication number: US3168388A
Application number: US222070A
Authority: US
Inventors: Earl T Martin; Robert F Theobald
Original assignee: Pittsburgh Plate Glass Co
Current assignee: PPG Industries Inc
Priority date: 1962-09-07
Filing date: 1962-09-07
Publication date: 1965-02-02
Anticipated expiration: 1982-02-02

Description

1965 E. T. MARTIN ETAL 3,168,383

APPARATUS FOR PRODUCING GLASS FIBERS Filed Sept. 7, 1962 SUCTION INVENTORS EARL 7.- mmzw/v Rosier F? 7/!!08410 A Tram/7 United States Patent 3,168,388 APPARATUS FOR PRODUCING GLASS FIBERS Earl T. Martin and Robert F. Theobald, Shelbyville, Ind., assignors to Pittsburgh Plate Glass Company, Pittsburgh, Pa., a corporation of Pennsylvania Filed Sept. 7, 1962, Ser. No. 222,070 1 Claim. (Cl. 651) This invention relates to the production of fibers and more particularly to guiding and threading apparatus for the fibers. Such apparatus finds particular use in the production of glass fiber products wherein glass filaments are drawn from a source of molten glass through a plurality of laterally spaced orifices and thereafter fed into a high velocity gaseous blast from a burner to make very fine fibers. In this type of operation, it is preferable to introduce the primary fibers or filaments singly into the gaseous burner discharge and spaced apart, so they do not Weld together when softened by the high degree of heat from the burner.

In order to achieve maximum production of fibers, they are normally spaced as close as practicable by means of a guide which supports the fibers as they are attenuated by the gaseous blast. The primary fibers or filaments are pulled from the orifices by rotation, resilient covered, friction rolls at a predetermined rate. The usual practice is to hand thread each fiber separately into the guide upon start of the operation, a tedious operation considering the number and size of the filaments. The present invention is such as to simplify the threading operation and the time required for threading the fibers.

In accordance with this invention, the apparatus includes the source of molten glass, orifices from which the glass issues as streams to be attenuated into primary fibers or filaments, the pulling rolls for drawing the filaments of glass and feeding the filaments to a hot gaseous blast and guide structure for guiding the filaments to and from the pulling rolls. The guide structure includes an upper guide member interposed between the orifices and the pulling rolls and a lower guide member between the pulling rolls and a burner from which hot gases are discharged to soften and produce fine fibers which are deposited onto a moving foraminous conveyor as a blanket or mat for subsequent processing. A comb portion of the overall guide structure is disposed between the orifices and the upper guide member.

The invention to be particularly described and claimed herein is the comb portion of the guide structure which is constructed to facilitate threading of the fibers thereinto and is also so constructed and positioned to permit the passage of stones-a mass of material of larger size and different composition than the filamentswith ease so that the continuity of the process is insured.

To further understand this invention, attention is directed to the accompanying drawing, in which;

FIG. 1 is a side view of the general arrangement for producing fibrous products and illustrating the comb structure of this invention in its proper location; and

FIG. 2 is a perspective view of the comb of this application.

Referring now to the drawings, there is illustrated a feeder connected to a source of molten glass 12 and having a plurality of laterally spaced orifices through which streams of glass issue pulled into primary fibers "ice or filaments 14 by a pair of

pulling rolls

16 and 18. The filaments are held spaced by upper guide means 20 which includes a pair of

members

22 and 24 each having a plurality of spaced grooves, one for eacch filament, which form openings through which the filaments 14 pass. Below the pulling rolls is a lower guide member 26 having a like number of spacing of grooves, each to receive a filament 14 as it is fed into a hot gaseous blast from burner 28. The blast attenuates the primary fibers and deposits the attenuated fibers as a blanket onto a moving conveyor 29 of known construction. Between the feeder 10 and the upper guide means 20 is a comb 30 of novel construction which serves to gather the filaments into a predetermined lateral area yet maintains each spaced from the others for delivery to the upper guide means 20 et seq. As previously mentioned, each filament 14 is hand threaded into the comb 30, a tedious job. An idler roller 31 having a cylindrical surface is supported on an axle just below the comb 30 to line up the fibers 14 into a plane for delivery to the upper guide 20.

The comb 30 as particularly illustrated in FIG. 2 includes a supporting portion 32 in the form of a bar of a heat resistant metal, such as stainless steel, although the particular metal or material is not of importance, so long as it resists the temperatures to which it is subjected, and a plurality of teeth identified for purposes of further description as 34 and 36. The teeth 34 are of one length while the teeth 36, which alternate with the teeth 34, are of a different length. As shown, the teeth 34 are longer than the teeth 36. The teeth are spaced a suflicient distance apart to permit the free passage of a filament 14 therebetween and are made of flexible metal for purposes to be described.

Flexibility of at least the pins 34, i.e., the longest length pins, materially assists an operator to easily thread the filaments into the spaces between the teeth. Each pin 34 can be flexed either to the right or to the left, as the case may be, to provide a V-shaped entrance to the space between adjacent teeth so that the filament can be inserted into the space. This is extremely important when the actual spacing, i.e., 0.06 inch cent-er-to-center, of the teeth is considered. The flexibility of the teeth serves at least another useful function. At times, stones are discharged from the feeder. Stones are usually larger in diameter than the filaments and the spacing of the comb teeth, and are of glassy materials dilfering from that of the filaments. They may be of the same composition as the refractory used to construct the glass melting tank. If the stones cannot pass the comb, disruption of the process occurs. Breakage of the filament will occur and the glass will discharge from the feeder without a pulling force being applied. This discharging stream may interfere with other filaments and cause welding of a group, requiring stoppage and rethreading of the filaments. Being flexible, the teeth flex upon contact with a stone and permit it to pass.

The comb of this invention has been described with particular reference to a particular fiber forming arrangement. It could be used with other arrangements without departing from the invention, set out in the appended claim.

We claim:

In apparatus for producing glass fibers including a source of molten glass, a bushing having a plurality of 3 4 orifices therethrough for discharging streams of glass from References Cited in the file of this patent said source, means for pulling said streams of glass to UNITED STATES PATENTS form fibers, the improvement which comprises a comb for separating said fibers, said comb including a plurality of 72,147,253 Hassold 141 1939 spaced flexible teeth fixed at one end to a support and de- 5 276310O Holtschulte SePt' 181 1956 fining therebetween spaces terminating at the support each receiving a fiber, alternate ones of said teeth being of FOREIGN PATENTS greater length than the others of said teeth to permit the 17,023 at a n y 1903 fibers to be easily threaded into said spaces. of 1902