US3041662A

US3041662A - Method and apparatus for forming glass fibers

Info

Publication number: US3041662A
Application number: US6923A
Authority: US
Inventors: Cochran John Kermit
Original assignee: Pittsburgh Plate Glass Co
Current assignee: PPG Industries Inc
Priority date: 1960-02-05
Filing date: 1960-02-05
Publication date: 1962-07-03
Anticipated expiration: 1979-07-03
Also published as: GB909154A; CH414960A; BE599859R

Description

y 1962 J. K. COCHRAN 3,041,662

' METHOD AND APPARATUS FOR FORMING GLASS FIBERS Filed Feb. 5, 1960 4 Sheets-Sheet 1 F'IGJ FlQ-Z IN VEN TOR. JOHN K. COCHIQA/V fiTTOR/VEX METHOD AND APPARATUSFOR FORMING GLASS FIBERS Filed Feb. 5, 1960 July 3, 1962 J. K. cocHRAN 4 Sheets-Sheet 2 INVENTOR. JOHN K. COCHRAN y 1962 .1. K. COCHRAN 3,041,662

' METHOD AND APPARATUS FOR FORMING GLASS FIBERS Filed Feb. 5, 1960 4 Sheets-Sheet 3 FIG.7

INV EN TOR. JOH/V K. COCHM/V J. K. CQCHRAN METHOD AND APPARATUS FOR FORMING GLASS FIBERS July 3, 1962 Filed Feb. 5, 1960 F IG.8

4 Sheets-Sheet 4 ZTR-i INVENTOR. JOHN K. COCHRA/V 4 TTOE/WFY United States Patent The present invention relates to a method of and an apparatus for forming glass fibers and it has particular relation to apparatus for automatically drawing a plurality of continuous glass filaments from a molten bath,

combining the filaments into a strand and winding the strand on a rotating cylindrical support.

In this process a plurality of glass filaments are drawn through orifices in an electrically heated, platinum alloy bushing and gathered together in the form of a strand. The strand is wound upon a forming tube mounted on a rotating cylinder called a collett. As the strand is wound on the forming tube, it is traversed by suitable means so that succeeding turns cross each other at a light angle and are not Wound in parallel relation on the forming tube. Usually the traversing means will move the strand through a 3 inch throw as it is wound on the forming tube. The traversing means'is axially reciprocated relative to the forming tube in order to wind the strand throughout a substantial portion of the length of the forming tube which may be 8 or more inches in length.

At the beginning of the fiber forming process, an operator pulls the individual filaments from the bushing by hand and groups them into a strand. The strand is passed over a gathering guide and is wound around one end of the collett beyond the forming tube. Rotation of the forming tube is then begun. It takes several seconds for the forming tube to come up to the proper drawing speed and during this time the strand which is wound on the collett is of too great a diameter. The strand which is formed during the start up is wound in a small area at the end of the collet and is held in this position by the operator. When the proper drawing speed is reached, the traverse is started and the strand is shifted by the traverse lengthwise of the tube so as to be wound during the remainder of the run in an area on the tube which is spaced from the strand formed during the start up on the end of the collett. When the forming run is completed, the strand is led back to the end portion of the collett containing the strand formed during start up and wound thereon as the forming tube rotation returns to zero. Thus, all of the oif size strand is located at one place on the collett and off of the forming tube. The off size strand is cut from the collett and is discarded before the forming tube is removed from the collett.

There is no twist in the strand as it is thus formed and a size is applied to the filaments prior to the winding of the strand on the tube in order to bond them together and maintain the integrity of the strand. An open wind, rather than a parallel wind, is desired on the forming tube in order to aid removal of the strand from the tube. If a parallel wind is used, the untwisted strand is very difiicult to remove when the filaments become broken. In this event, successive turns of the strand become entangled and it soon becomes impossible to unwind the strand and remove it from the tube. The open wind is such that the strand is traversed the length of the tube for a relatively few turns of strand on the tube, i.e., 2 to 5 or more turns for a 7 to 10 inch long package for each traverse of the length of the tube. With this type of wind the succeeding turns of strand cross each other ata minimum angle of at least 5.

The spiral wire traverse shown in US. Patent No.

3,041,662 Patented July 3, 1962 2,391,870 has proved to be satisfactory for traversing a strand at the very high rate of speed which is employed to wind the strand on a forming tube. This traverse, in addition to rotating about its own axis, is reciprocated axially in order to distribute the strand over the length of the tube. This type of traverse requires that there be a certain minimum tension on the strand as it passes over the cams of the traverse to hold it on the cams as they tendto push the strand toward either end of the forming tube. There is a natural tendency for the strand to return to the center of the forming tube, and there is a minimumtension which is required to overcome this tendency and maintain the strand at its proper position on the cam to produce the desired open wind. If this tension becomes too great, there is the problem of the individual filaments of the strand breaking at the gathering guide due to too much friction as they pass over the guide. As soon as one filament breaks, the whole strand usually breaks. This problem of tension on the strand has become aggravated by a desire to have the glass fiber process performed all on one floor; whereas, it has been previously conducted on two floors.

It is an object of the present invention to produce a glass fiber strand with a minimum amount of distance between the bushing and forming tube while imposing a minimum amount of tension on the strand during the fiber forming process. It is a further object of the invention to provide an automatic fiber forming process so as to minimize the time required for the operator to attend the fiber forming run. It is also an object of the invention to provide an automatic winder which is I tical, shifts the collett and forming tube back to the I start up position at the end of the run, holds the forming tube and collett in fixed position for the operator while he is cutting the ofi-size strand from the end of the collett, and holds the collett in fixed position while the operator replaces the filled forming tube with an empty forming tube. 1

The mannerin which these and other objects of the invention are accomplished is described in further detail in conjunction with the drawings in which:

'FIGURE 1 is a diagrammatic elevation of the fiber forming apparatus;

FIGURE 2 isa side view of FIGURE 1; FIGURE 3 is an elevation of the winder; FIGURE 4 is a plan view of the winder shown in FIGURE 3; Y 1 FIGURE 5 is a section through the center of the colett;

FIGURE 6 is an end view of FIGURE 5; FIGURE 7 is a schematic drawing of the pneumatic system of the winder, and

FIGURE 8 is a schematic drawing of the electrical The bushing 12 is provided with a series of orifices 13 which are defined by tips 14 winder.

3 suspended from the main portion of the bushing. The molten glass flows through the tips and forms in small cones 15 suspended from the tips. The orifices are aligned in fouror'more rows, having a greatmany tips in each row so that the total number of tips is about 200 to 400. A smaller or greater number of rows or tips may be present in the bushing.

j Glass filaments, 16 are pulled from the cones. 15 of glass at a very high rate -of speed, for example 5,000to 20,000 feet per minute, usually 12,000 to 15,000 feet per minute, and-wound on a rapidly rotating forming tube 18 mounted on a collett 19. The collett maybe approximately 6 to 8 inches in outside diameter and may rotate at approximately 6,000 to 8,000'r.p.m'., depending upon the size of the fiber to be produced. The glass filaments 16 are grouped into a strand 20 as'they pass over a guide 22' prior to being wound on the forming tube 18.

4 As .the strand 20 is wound on the tube 18, it is rapidly traversed in an openjwind along the length of the tube by means of a traverse 25.1 The traverse 25 is composed of a spindle having a pair of complementary, spirally disposed wire cams mounted on it. The spindle is rotated at 1,000 tov 2,500 r.p.m., and the cams push the strand hack and forth across the face of the forming tube through a 2 to 3 inch throw for each revolution of the spindle.

The strand is distributed throughout the length of the forming tube by therelative motion of the forming tube with respect to the traverseas caused by oscillating the V forming tube and collettj axially during the fiber formins Usua1ly an aqueous size'containing a'liquid binder and a lubricant such as a combination ofstarch and a vegetable oil is applied to the individual filaments of the strand as they pass .over a moving applicator 27 which is mounted just above the guide 22. The applicator may be in the form of a roller 28 or moving belt having a film of size supplied to it- The. filaments pass over the roller or belt at some tangential point-for momentary contact with the sizing solution to transfer the solution from the applicator to the filaments. An example of a suitable size applicator is shown in US. Patent 2,873,718. l The winder, including the traverse 25 and the collett 19, is generally indicated at 30. It is composed of a base 32and sheet metal framing enclosure 33 mounted on the base. A' carriage 34 is mounted on the base on'a pair of slides 36 which. are mounted in supports 38 rigidly fas- -'-tened to the base Accordion-like sleeves 39 are attached ofthe motor. The motor 60 operates on alternating current and the plugging is achieved electrically by reversing two of the three current leads to the motor so as to apply reversetorqne to the motor, thus reducing the speed of its rotation prior to application of. the brake 70.

The collett 19 is shown in detail in FIGURES 5 and 6. The collett is composed ofa cylindrical body portion 75 in thefor-m of a sleeve which fits snugly onto the end of the spindle 62 "The spindle 62 is provided with integral keys 78 and the collett body 75 has corresponding recesses in it so that the collett will rotate with the spindle. A lock nut 79 is screwed onto the end of spindle 62 to hold the "body 75 ontothe spindle. A cylindrical collar 80 is attached to the rear end of the collett body 75 by meansof bolts 81. The collar 80 is provided with forwardly facing annular depressions 82 and 84. A ring 86 is fastened to the front or outer end of the collett body 75 by means of bolts 87. The ring 86 has a rearwardly facing annular depression 89 in it which is of the same size as the depression 82 and which is aligned axially with depression 82. a

The

bolts

81 and 87 which hold the collar and ring 86pm to the-collett body also hold in place a series of guide blades 92 which are integral with and spaced evenly in slots around the circumference of the collett body 75. A series of long bars .or fingers 95 are fitted onto the guide blades 92 with lugs 96 on their ends fitting into depressions 82 and 89. Thesebars are held in place on the collett by means of the lugs 96 which are slightly smaller than the depressions 82 and 89 so as to permit radial movement of the bars in the depressions. The bars are held in their outermost position as limited by the

annular projections

98 and 99 on the collar 80 and ring 86 respectively and are held thereagainst by a series of compression springs v 100 spaced circumferentially around the col- 'lett between the lugs 96 and the collett body 75. In cross section, the bars 95 are arcuate on the top so as to form a substantially continuous cylindrical surface on the outside of the collett. Their side meeting faces taper inwardly corresponding to radial lines drawn from the axis of the spindle 62. The bottom surfaces of the bars are flat. Intermediate the ends of each bar in their bottom surface is a groove corresponding in shape to guid to the supports 38 and the carriage34 so as to protect the -lubric'ated slides 36 from any dirt or other foreign sub blade 92.

A- slight space is left between the adjacent bars 95 to permit their movement in and 'out in a radial direction. The inward movement is required when the forming tube 18 is slipped on to the collett. The forming tube 18 is limited in its inward position by the retaining depression 84. The bars 95 move toward the spindle as the tube is slipped over thenr and then press radially outwardly rod 4-3 which islrigidly attached tothe carriage at 45 and whose

pistons

47 and 48 are mounted respectively in an oil cylinder'50 and air cylinder52 mounted in tandem. The oil cylinder serves as a dash-pot for smoothing out the movement of the pistons as caused by the alternating is supplied to opposite ends, of the cylinder 52 by

air lines

54 and 56 which are connected to a four way, two

l position, 'bleeder actuated, balanced, air vadve 58. The I detailsof the valve 58 and its method of controlling the air how to. the cylinder 52 are discussed further in conjunction, with the description of the operation of the v The drive for the collett 19 is niotorotl'which is adjustably mounted "on the-carriage 34. The collett 19 is mounted on a spindle 6 2 which is supported in a cylindri cal bearing-on an upright portion 65 of the carriage 34. The spindle 62fis rotated by 'means of a belt 68 which is against the tube to hold the tube in place. The collar 86 is provided with four depressions spaced symmetrically around the collar at the outer end of the collett. These depressions permit severing the off-size strand from the end of the collett to remove it at the end of a run.

' The mounting of the traverse 25 is shown generally in V '1': FIGURES'I and 2 and in'detail in FIGURES 3 and 4. air pressure on the piston, 48 in the air cylinder 52. Air

The traverse25 is composed of a spindle having a pair of complementary, spiral, wire cams .112 mounted on the ends of the spindle 110'. The construction of the spiral is described in greater detail in 1.1.8. Patent 2,391,870. A plate 114 is, rigidly attached to an upright supportllS monntedon base 32 and it serves as a support for the spindle and its motordrive 1 16. The motor 116 is rigidly fastened to andsupported on the plate 115 and the spindle extends through two hollow-cylindrical bearings in proiections 1 1 8 extending downwardly from the plate 115. A

pair of guides 12!) mounted on the spindle prevent axial movement of the spindlein the bearings 118. The alignspindle 110 rotates but does not move axially as does the collett spindle. I

The traverse 25 is mounted so that its central point with respect to travel of the strand over it is in a vertical plane with the guide 22 and the center of the bushing 12, said plane being perpendicular to the axis of the traverse spindle 110 and collett spindle 62. The guide 22 is located directly under the center of the bushing but the axis of the traverse 25 is offset in the aforementioned vertical plane approximately to from a vertical line drawn through the center of the bushing and the guide 22. This angle is just slightly larger than the angle formed by the outside or end filaments with the vertical line. The collett 19 and forming tube 18 are mounted below the guide 22. The strand passes over the traverse under slight tension as it moves between the guide 22 and the forming tube 1 8. As shown in FIGURE 1 the spindle 110 of the traverse is slightly to the left of an imaginary line drawn from the guide 22 to the point on the edge of the forming tube where the strand first contacts the tube. This positioning is required so that the traverse is able to positively engage the strand and move it back and forth across the forming tube surface during the winding.

The operation of the winder in the glass fiber forming process can best be described in conjunction with the description of the schematic drawing of the pneumatic system in :FIGURE 7 and the schematic drawing of the electrical system in FIGURE 8. In starting the fiber forming process the operator pulls the strand 20 across the guide 22 and wraps it around the end of the collett extending beyond the forming tube 18. The collett 19 is at its innermost position at the start of the run. While doing this, he has his foot on a foot switch 125 having contacts FS-1 and -FS2 located in a llO-volt alternating current circuit generally designated 126 in FIGURE 7. =Depression of the foot switch opens contact F-S-Z. It also closes a contact FS-1 in a circuit in series with a normally closed pushbutton switch PB1 and a coil 1C=R of a relay having normally open contacts 1OR-1 and 1011-2 which then close. The contact 1CR1 is in parallel with the contact FS-1 and in series with coil 1CR and switch PB-l so as to provide a holding circuit to maintain the coil 1CR energized upon release of the foot switch 125. Release of the foot switch 125 closes contact FS-2 which is located in another circuit in series with normally open, now closed, contact 1CR-2, normally closed contact PC-l and coil 1M of a starter relay for the collett motor 60. This energizes coil 1M of the relay having normally closed contact -1M-1 and normally open contacts 1M-2 and 1M-3.

When coil 1M is energized, contact 1M-3 in another circuit is closed to energize a solenoid B which releases brake 79 and power is supplied to motor 60' so that the collett begins to rotate and rapidly picks up speed. Also, when coil 1M is energized, interlock contact 1M- 2 is closed in another circuit to energize a'collett oscillating timer 1T-R and a collett motor plugging timer 2TR in parallel with each other and in series with contact =1M-2. The timer lTR is set, e.g., for about 4 to 6 seconds 'to permit the collett motor 6%} to attain sufiicient speed to rotate the collett at about 7,650 rpm. When 1TR times out, its normally open contact 1TR-1 of the on-delay type closes.

The contact lTR-1 is in series with contact vlM-Z, with a solenoid :SV-l of a normally closed, spring biased, solenoid valve 128 and with a timer 3111. The solenoid SV-l and timer 3TR are in parallel with each other. The solenoid valve 128 controls the oscillation of the collett and the timer 3TR through its normally open contact 3TR-1 of the on-delay type initiates the rotation of the traverse.

The energizing of solenoid SV-l opens the solenoid valve 128. This opens a portion of the pneumatic system for controlling the oscillation of the collett. The pneumatic system is shown schematically in FIGURE 8. Air valve 58 as previously mentioned controls the air supply to each side of the piston 48 mounted in air cylinder 52. The air valve 58 is of the balanced type, e.g., as shown in U.S. Patent No. 2,607,197.

' to be exhausted alternately to the atmosphere.

. 6 :The air valve 58 is composed of a casing providing a chamber :132to which air under high pressure is constantly supplied through an inlet port 133 connected by pipe 134 to'an air pressure source. A spool or plunger 135 p is mounted within the chamber 132 for movement lengthwise of the chamber. The spool 135 is provided with pistons 137 and 138 at each end which in combination with the walls of the chamber 132 act to separate the chamber into three sections, a central section 139 into which the air under pressure is continuously provided, and sections 140 and 141 at the ends of the chamber. The central section of the chamber is connected to the end sections 140 and 141 by

small ports

142 and 143 in the pistons to provide for eventual equalization of the pressure in the three sections of the chamber #132. This permits the spool 135 to be in a balanced position within the chamber 132. The spool is moved lengthwise in the chamber by exhausting the air from either end portions 140 or 141 to temporarily unbalance the air pressure within the sections of the chamber and thus cause the spool to move toward the end of the valve from which the air has been exhausted.

One wall of the central portion of the chamber 132 Pro vides a seat for a slide valve connected with the spool and normally urged by spring 144 against the seat. The inlet port 133 is located beyond the range of movement of the slide valve 145 so that air under pressure is constantly supplied to the chamber 132. The casing [130 has three passages opening into it through the wall forming the valve seat. Two of the

passages

146 and 147 are connected by

air lines

54 and 56 to opposite ends of air cylinder 52. The third passage 150 is connected by a suitable line 151 to the atmosphere through muffler 152 and serves as an exhaust. In one position of the slide valve the passage .146 communicates with the central section 139 of the chamber and it causes air under pressure to be directed toward one side of the piston 48 in air cylinder 52. In this position the passage 147 is connected through the valve 145 and passage'150 to the atmosphere and thus serves as an exhaust of the air from the other side of the piston 48 in air cylinder 52. In the other position of the slide valve 145, the passage 147 communicates with the central section 139 of the chamber 132 and the passage 146 communicates with the atmosphere through valve'145 and passage 150.

The sliding of valve 145 is accomplished by alternately bleeding air from the end sections 140 and 141. This is accomplished by means of

poppet valves

153 and 154 which are connected to end sections 140 and 141 respectively through

air lines

155 and 156 connected to

passages

157 and 158 in the end walls of the casing 130. The

spring biased, normally closed, solenoid valve 128 is located in the air line 156 connecting the passage 158 with poppet valve 154. I 1

The

poppet valves

153 and 154 are mounted'on the base 32 of the winder 30 in a line parallel to the travel of the carriage and the collett. A bar 159 is rigidly attached to the side of the carriage 34 and as the carriage moves back and forth, the bar 159 alternately contacts the poppet valves to open them and cause the end sections 140 and 141 of the chamber 132 in the valve 58 The oil cylinder 50 connected to the air cylinder 52 causes the movement of the carriage to be smooth rather than abrupt. The cylinder 50 contains oil and this oil bleeds through an opening 160 in the piston 47 mounted on the piston rod 43 which extends through the oil cylinder to the air cylinder, and on which'the piston 48 is also mounted. t

The solenoid valve 128 controls the operation of air valve 58 to determine whether or not the carriage 34 returns to and remains in its innermost starting position or whether it oscillates between two positions which are spaced outwardly from the innermost st-arting position. When the solenoid valve 128 is closed, the line 156 connecting passage 158 to poppet valve 154 is closed and no air escape from end sectionlfl whether the poppet valve 153 is open-or not. If the carriage is in its innermost position and the solenoid valve 128 is closed, the carriage will stay in that position. When the carriage is in the innermost position, the bar 159 holds the poppet valve 154 open; howeventhe carriage 34 cannot move forwardruntil the solenoidvalve 128 is opened to communicate through the exhaustline 156 the end section 141 with'poppet valve 154. The various valves and pistons in the pneumatic system are shown in FIGURE 8 in their position 'at start upwith the piston -48 in cylinder 52 being in the first or innermost position and exhaust line 156 'is now open to valve -4. .The

bal-ancedcondition of air valve58 isupset and the spool 135 and slide valve 145 move to reverse the flow of

air throughlines

54 and 56 to the, cylinder 52 to cause the piston 48 and carriage 34 to'move forward. As the carriage 34 approaches its second or outermost senses and collett. This breaks the strand and the fiber forming isterminated j j,

When the foot switch 125 is depressed, the solenoid SV-l of valve 128 is tie-energized because contact lM-Z is opened by the de-energization of coil IM. This closes exhaust line 156 and prevents the exhausting of air to. the atmosphere from end section 141 in the ,air valve 58. If the carriage 34 is moving inwardly at the time the solenoid SV-1 of valve 128 is de-energized,.it will conposition, the'bar 159 engages poppet valve 153 to exhaust through line 155 from'end section 140 of the chamber 132 and unbalance the valve 58. The spool 135 and, valve 145 are moved to their alternate position and the flow of air in

lines

54 and 56 to the cylinder 52 is again reversed to stop the carriage at the second or outermost position and reverse its movement. A similar procedure is followed when the bar 159 engages poppet valve 154 on the return motion'of the carriage aid the carriage is stopped and reversed at a third positionintermediate the. first and second position.

The balancin and-unbalancing of the air valve. 58

'causes the carriage and collett' to move automatically posedend of the collett where the cit-size strandformed during the start up ofthe run is collected.

As described above the collett motor 60 was first started to rotate collett 19am then aftera delay through timer lTR and its contact lTR-l, the valve 128. was opened to initiate the movement of carriage '34 toward the outermost position. Because timer3TR is initiated at the time Y that sole'noid SV-l is energized, the timer STR'after its delay (about 1 'to 2'seconds) closes anorinally open contactSTR-l of the on-del'ay type. .Thus, after a short delay'the'coil 2M of the starter relay for traverse motor 1'16 is energized to begin rotation of the traverse. With this arrangement the traverse does not begin to rotate until the on-size strand is being wound on the forming tube.

' At the same time that the traverse motor isstarted, a

synchronous motor timer -4TR is energized, because timer 4TR is in parallel with coil 2M and'in series 'with contact 3TR1.'- This timer is set for the length of the run, for example, 10 minutes. At the end of 10Iminutes timer times out to close its normally open contact 4TR-.-1 so that a warning light 'L in series with contact" FR-pl in a circuit is lit to indic'ateito the operator'that the is complete. Theoperator then presses on the root switch 125 to'open contact FS-2. 'This de-energizes 'coil 1M of collett motorv 6,0. At the, samestime the M operator leads the strand byhandoli the end'ot the'tube tinue on to the innermost position even though poppet valve 154 is contacted by the :bar 159 because valve 128 is closed. If the carriage 34 is traveling in an outward direction at the time solenoid SV-l of valve 128 is deenergized, the outward travel will continue until the poppet valve 153 is contacted. ,When poppet-valve 153 is contacted, the air valve 58 will be unbalanced, the air to the cylinder will be reversed to stop carriage'34 and start it moving inwardly. The carriage 34 will continue past the position defined by poppet valve 154 to its innermost position. As mentioned above, the solenoid 'B was energized by the closing of contact 1M-3 in series with the solenoid- B upon the energization'of coil 1M. At the time that coil 1M is de-energized by the opening of contact FS-2 through the depressing of 'foot switch 125, a coil PC of a plugging relay for motor is energized to provide a reversing torque for collett motor 60 so that the rotation'of motor 60 and collett 19 decreases. The relay containing coil PC at this time closes a normally open contact PC-2 in parallel with contact 1M-3 and inseries with solenoid B so that the energization of solenoid B continues during plugging of motor 60.

The coil PC is in series with normally closed contact lM-l and'a normally open contact 2TR-1 of time delay relay 2TR.' Upon the energization of coil 2TR during start up of operations, contact 2TR- 1 was closed. As a result, coil PC is energized through the closing of contact lM-l upon the de-energization of coil 1M. However, the 'de-energizati-on of. coil 1M that opens contact IM-2 for de energization of solenoid SV-1 also deenergizes'coil 2TR so that contact 2TR-1 opens after its delay of about 5 seconds to de-energize coil'PC. This stops the reversing torque and at the same time de-energizes solenoid B so that the brake moves into its brak ing position. With this arrangement the braking is accomplished only after the spindle has been reduced to a slow speed of rotation.

During the'energization of coil PC to provide the reversmg torque the energization of'coil 1M is prevented because normally closed contact P04 is open. As soon as coil PC is de-ener'gized contact PC-1 closes. The operator must keep switch depressed to keep contact PS-2 open in order that coil 1M remains de-energized. Otherwise, contact 1M-3 would close to energize solenoid B which would prevent the operation of the brake. Also the closing of contact FS-Z would start motor 60 through energization of coil lML This above described method of stopping motor 60 is faster and more positive than previous systems employed in glass fiber winders. This decreases the time required between runs and increases the time which the winder is available for fiber forming. The plugging of the motor permits useof the mechanical brakerat low speeds only and this prevents overheating of the brake and reduces maintenance which would otherwise be required for repairing the brake.

f By holding the motor spindle in fixed position, the collett in turn is held steady at the end of therun. This facilitates the removal of the off-size strand from the end of the collett and the removal of the forming tube from the collett. 'The operator cuts the ofi-size strand from the collett prior to the removal of the forming tube and; this canbe done more easily without danger of the operator cutting himself during the severing'of the strand. The forming tube can bere'moved' and a new one in- 9 serted on the collett more easily when the collett is held stationary.

When the operator releases his foot from the foot switch 125, the contact FS-Z is closed and a fiber forming run as described above is ready to begin again. If the operator wishes to discontinue the fiber forming operation and not start a new run, the manual stop button PB-l can be pressed rather than the foot switch at the end of the run.

Obviously, mechanical and electrical equivalents may be substituted for certain of the elements of the apparatus and some modifications of the apparatus can be made to obtain the same sequence of events and results obtained. For example, the winding operation may be made completely automatic by relocating the contact 4TR-1 to be in series with the stop button PB-1 instead of as shown and described. In this case the collett is stopped and moved to its innermost position at the end of the run automatically rather than requiring the operator to depress the foot switch to stop the fiber forming operation. It is preferred, however, to have the operator stop the fiber forming run rather than have it automatically stop for several reasons. If the operation is stopped automatically, glass which is extruding slowly from the bushing orifices may fall on to the finished package and ruin it. The molten glass may also fall on to the winding equipment and cause some damage to it. Also, automatically stopping the operation at a given time eliminates the formation of good strand on the forming tube during the short interval of time that is required for the operator to see the light and stop the run, thereby reducing production by a certain small percentage.

The above description of the apparatus and the details of its operation are intended to be exemplary and not limiting upon the scope of the invention except as set forth in the accompanying claims.

I claim:

1. A method of forming a glass fiber strand which comprises drawing a plurality of individual glass filaments from a source of glass, applying a size to the glass filaments, passing them through a stationary guide to group them into a strand, wrapping the strand in substantially parallel relation around one end of a cylinder while the cylinder is located in a first position, commencing rotation of the cylinder, increasing the rotation of the cylinder to a desired speed, thereafter moving the cylinder axially to a second position so that the strand is wound around the other end of the cylinder, engaging the strand at one location intermediate the guide and the cylinder after the axial movement of the cylinder from the first to the second position has begun to impart a slight traversing movement to the strand as it is wound on the rotating cylinder, reversing the axial movement of the cylinder to cause the cylinder to move axially to a third position intermediate the first and second positions, axially reciprocating the rotating cylinder between the second and third positions while imparting a slight traverse to the strand being wound upon the cylinder so as to provide a supply of the strand on the cylinder, returning the cylinder to the first position, discontinuing the traversing movement of the strand and discontinuing the rotation of the cylinder.

2. Apparatus for forming a glass fiber strand which comprises a bushing, a guide for grouping the filaments drawn from the bushing into a strand, means for applying a size to the filaments and means for drawing the strand over the guide, said drawing means comprising a base, a carriage mounted on the base for longitudinal movement thereon-between first, second and third positions, the third position being intermediate the first and second positions, a cylinder mounted on the carriage for movement therewith in an axial direction, a traverse mounted adjacent the cylinder so as to be in line with the bushing, guide and one end of the cylinder when it is in the first position, means for rotating the cylinder, means for moving the carriage, means for actuating the carriage moving means to cause the carriage to move from the first position toward the second position, means for rotating the traverse, means for actuating the traverse rotating means, said traverse rotating actuating means being responsive after a delay to the means for actuating movement of the carriage from the first position toward the second position, means for controlling oscillating movement of the carriage between the second and third positions and means for returning the carriage to the first position and stopping the rotation of the cylinder and traverse.

3. Apparatus for forming a glass fiber strand which comprises a bushing, a guide for grouping the filaments drawn from the bushing into a strand, means for applying a size to the filaments and means for drawing the strand over the guide, said drawing means comprising a base, a carriage mounted on the base for longitudinal movement thereon between first, second and third positions, the third position being intermediate the first and second positions, a cylinder mounted on the carriage for movement there with in an axial direction, a traverse mounted adjacent the cylinder so as to be in line with the bushing, guide and one end of the cylinder when it is in the first position, means for rotating the cylinder, means for actuating the cylinder rotating means, means for moving the carriage, means responsive to the cylinder rotating actuating means for actuating after a delay the carriage moving means to cause the carriage to move from the first position toward the second position, means for rotating the traverse, means for actuating the traverse rotating means, said traverse rotating actuating means being responsive after a delay to the means for actuating movement of the carriage from the first position toward the second position, means for controlling oscillating movement of the carriage between the second and third positions and means for returning the carriage to the first position and stopping the rotation of the cylinder and traverse.

4. An apparatus for forming a glass fiber strand which comprises a bushing, a guide for grouping filaments drawn from the bushing into a strand, means for applying a size to the filaments and means for drawing the strand over the guide, said drawing means comprising a base, a cylinder mounted on the base, an electric motor for rotating the cylinder, a normally engaged brake for stopping rotation of the cylinder, means for actuating the motor, means responsive to the motor actuating means for disengaging the brake, stop means for deactuating the motor actuating means, means for plugging the motor, means responsive to the stop means for actuating the motor plugging means, means responsive to the motor plugging actuating means for maintaining the brake disengaged, and means for deactuating the motor plugging actuating means after a period of time to stop the motor plugging and permit the brake to stop rotation of the cylinder.

5' Apparatus for forming a glass fiber strand which comprises a bushing, a guide for grouping filaments drawn from the bushing to a strand, means for applying a size to the filaments and means for drawing the strand over the guide, said drawing means comprising a base, a carriage mounted on the base for longitudinal movement thereon between first, second and third positions, the third position being intermediate the first and second positions, a cylinder mounted on the carriage for movement therewith in an axial direction, an electric motor for rotating the cylinder, a normally engaged brake for stopping rotation of the cylinder, means for actuating the motor, means responsive to the motor actuating means for disengaging the brake, means for moving the carriage, means responsive to the motor actuating means for actuating movement of the carriage after a delay from the first position toward the second position, a traverse mounted adjacent the cylinder so as to be in line with the bushing, guide and one end of the cylinder when it is in the first position, means for rotating the traverse, means for actuating rotation of the traverse, said traverse ro- {men actuating me ns ing responsive as s new,

the means for actuating movement of the carriage from ing the brake disengaged, and means for deactuating the motor plugging actuating means after a period of time to stop the motor plugging and permit the brake to stop rotation of the cylinder. t

6. An apparatus for forming glass fibers which comprises a'bushing, a guide for grouping filaments drawn from the bushing into a strand, means for applying a size to the filaments andrmeans for drawing the strand over the guide, said drawing means comprising a base, a carriage mounted on the base for longitudinal movement thereon between first, second and third positions, the third position being intermediate the first and second positions, a cylinder'mounted on the carriage for movement, therewith in an axial direction, means for rotating the cylinder, a first control means for actuating the cylinder rotating means, driving means for moving the carriage longitudinally on the base, a second control means for causing the carriage driving means to move toward thevfirst position, a third control means to hold the carriage in the, first position, a fourth control means responsive to the first control means for deactuating after a delay the third control means and for actuating after the delay the car.- riage driving means to cause the carriage to move from the first position toward the second position, a traverse mounted adjacent the cylinder for operation at a single station intermediate the cylinder and guide and in line with the bushing, guide and one end of the cylinder when it is in the first position, means for operating thetraverse, afifth control means responsive to the fourth control means for actuating the means for operating the traverse after the actuation of the carriagedriving means, a sixth control means operating in combination with the second and fourth control means to permit reciprocatory movement of the carriage between the second and third posi- V rions by the carriage driving means, a seventh control meansfor actuating the third control means and deactuating the first, fourth and fifth control means to cause the carriage to return to the first position, deactuate the means for rotating the cylinder and deactuate the means for 1 operating-the traverse, means for stopping rotation of the cylinder, and means responsive to theseventh control means for actuating the means for stopping rotation of the cylinder.

7. An apparatus for forming glass fibers which comprises a bushing, a guide'for grouping filaments drawn from the bushing into atstrand, means for applying a size to the filaments and means for drawing the strand over the guide, said drawing means comprising abase, a carriage mounted on the-base for longitudinal movement thereon between first, second and third positions, the third position being intermediate the first and second positions,

' :a cylinder mounted "on the carriage for movement therecarriage in the first position, a-fourthcontrol means for deactuating after 'a delay the thirdtcontrol means and for actuating after the delay thecarriage driving means to 1 cause the carriage to move from the first position toward the second position, said'fourth control means being re-' sponsive to said first control means, a traverse mounted adjacent the cylinder for voperation at a single station intermediate, the guide and cylinder and 'inline with the bushing, guide and one endio f the cylinder when it is in the first position, means for operating the-traverse, afifth control means responsive to the fourth control means for actuating the traverse operating means after the actuation of the carriage driving means, a sixth controlrme ans' operating in combination with the, second. and fourth control means for controlling reciprocatory movement of the carriage between the second and third positions, a seventh control means for deactuating the first and fifth control means to stop the power to the motor and stop the traverse, said seventh control means also deactuating the fourth control means and actuating the third control means so as to return the carriage to the first position, means for plugging thev motor, means responsive to the seventh control means for actuating the motor plugging means, means responsive to the motor plugging actuating means for maintaining the brake disengaged and means for deactuating the motor plugging actuating means after a period of time to stop the motor, plugging and permit the brake to stop the rotation of the cylinder.

8. Apparatus for winding fibers which comprises a base,

= a carriage mounted on the base for reciprocal longitudinal movement thereon between first, second and third posi- 'tions, the third position being intermediate the first and second positions, acylinder mounted on the carriage for movement therewith in an axial direction, a traverse mounted adjacent the cylinder so as to be in line with one end of the cylinder when it is in the first position, means for rotating'the cylinder, means for moving the carriage, means for actuating'the carriage moving means to cause the carriage to move from the first position toward the second position, means for rotatingthe traverse, means for actuating the traverse rotating means, said traverse rotating actuating means being responsive after a delay to the means for actuating movement of the'carriage from the first position towardlthese'cond position, means for controlling oscillating movement of the carriage between the second and third positions and means for returning the carriage to the first position and stopping the rotation of the cylinder and traverse.

9. Apparatus for Windingfibers which comprises a base, a carriage mounted on, the base for movement between a first position, a second position and a third position intermediate the first and second positions, a cylinder mounted on the carriage'and movable therewith in an axial direction, an electric motor for rotating the cylinder, a normally engaged brake for stopping rotation of the cylinder, means for actuating the motor, means responsive to'the motor actuating means for dis engaging the brake, means for moving the carriage, means responsive to themotor actuating means for actuating movement of the carriage from the first position toward the. second position, means for controlling oscillating movement of the carriage between the second and third positions, means for returning the carriage to the first position and for reactuating the motor actuating means,

means for plugging the motor for a timed interval after the motor actuating means, has beendeactuated, means for actuating the motor plugging means, means responsive to the motor plugging actuating means for maintaining the brake disengaged, and means for engaging the brake when -themotor is not running and is not being plugged; V a

" 10. An apparatus for winding fiberswhich comprises 'a base, acylinde r mounted on the base, an electric motor for rotating the cylinder, a brake for stopping roitatio'ii orthe" cylinder, means for actuating the motor, means responsiveto the motor actuating means for disengaging the brake, stops means for deactuating the motor actuating means, means for plugging the motor, means responsive to the stop means-for actuating the motor 13 plugging means, means responsive to the motor plugging actuating means for maintaining the brake disengaged, and means for deaciuating the motor plugging actuating means after a period of time to stop the motor plugging and permit the brake to stop rotation of the 5 cylinder.

References Cited in the file of this patent UNITED STATES PATENTS 2,391,870 Beach Jan. 1, 1946 10 14 Slayter et a1. Apr. 23, 1946 Denault July 22, 1947 Momberg et al Aug. 2, 1949 Simison Sept. 13, 1949 Cook July 11, 1950 Stream et a1. Dec. 23, 1952 Keight Mar. 10, 1953 Toulmin Apr. 21, 195.3 Stephens et a1. Aug. 5, 1958 Schaefer May 12, 1959