US3771701A

US3771701A - Apparatus and method for accelerating strands

Info

Publication number: US3771701A
Application number: US00300941A
Authority: US
Inventors: J Brunk; E Brosch
Original assignee: Johns Manville
Current assignee: Johns Manville Corp; Johns Manville
Priority date: 1972-10-26
Filing date: 1972-10-26
Publication date: 1973-11-13
Anticipated expiration: 1990-11-13
Also published as: NL7314222A; JPS4993639A; JPS5040175B2; FR2204716A1; DE2354306A1; SE405611B; BE806510A; BR7308419D0; IT996328B

Abstract

A strand feeding assembly is provided with a strand starting cone and cone idler which cooperate to accelerate a strand introduced between the idler and cone to the proper speed for the strand feeding assembly. The cone is either affixed to and rotates with a roller of the strand feeding assembly, or the cone is independently driven to enable the selection of a rate of acceleration for the strand best suited for the process and type of strand being accelerated.

Description

[ Nov. 13, 1973 United States Patent Brunk et a1.

2,539,978 1/1951 VanDijk.......................... 226/184 X APPARATUS AND METHOD FOR ACCELERATING STRANDS Primary Examiner-Richard A. Schacher Attorney.lohn A. McKinney et al.

[75] Inventors: Jack Laurence Brunk, Toledo;

ABSTRACT Village, Colo.

Oct. 26, 1972 [22] Filed: A strand feeding assembly is provided with a strand 1 1 Appl. No.: 300,941 starting cone and cone idler which cooperate to accelerate a strand introduced between the idler and cone to the proper speed for the strand feeding assembly. The cone is either affixed to and rotates with a roller of the strand feeding assembly, or the cone is indepen- [52] U.S. 226/1, 22'6/91, 226/184 [51] Int. B65h 17/12 [58] Field of Search 226/184, 1, 12, 24,

dently driven to enable the selection of a rate of acceleration for the strand best suited for the process and type of strand being accelerated.

13 Claims, 4 Drawing Figures 1,962,029 Murphy 226/184 x APPARATUS AND METHOD FOR ACCELERATING STRANDS CROSS-REFERENCE TO RELATED APPLICATION This application discloses material which is the subject of a commonly assigned application Ser. No. 300960, filed Oct. 26, 1972 in the name of Samuel Richard Genson.

BACKGROUND OF THE INVENTION The present invention relates to a strand accelerating apparatus and, in particular, to a strand accelerating apparatus which can be employed both during the start-up or during the operation of a process to introduce or reintroduce strands into the operation. 7

Various processes require that a strand run at a high rate of speed in order for theprocess to be economically and commercially feasible. One such process is a process for producing chopped glass strand from a continuous stand. The strand in this type of operation attains speeds of 3,000 to 10,000 feet per minute and, consequently, this type of process poses several problems. When taking a strand running at a speed of about to 100 feet per minute and feeding the strand into a chopper traveling at a speed of about 3,000 to 10,000 feet per minute, the stresses caused by the rapid, almost instantaneous acceleration of the strand can cause the strand to break. In addition, when a plurality of strands are being chopped simultaneously, strand breakage during a chopping operation can cause an undesirable interruption in the multistrand process while the broken strand is reintroduced into the process.

In seeking at least a partial solution to this problem, various types of pull rolls (some using variable speed drives) have been utilized in the past to accelerate strands. However, at best, this type of apparatus has only been partially successful and the need has remained to provide an apparatus and method for introducing' or reintroducing strands into such a process which overcome these problems of the prior art.

SUMMARY or THE. INVENTION Consequently, it is an object of the present invention Y to provide an'apparatus and method of accelerating a strand from a rest condition or almost a rest condition up to a speed of about 3,000 to 10,000 feet per minute without accelerating the strand so quickly that it breaks. It is a further object to provide an apparatus and method of accelerating a strand wherein one strand of a multistrand process can be reintroduced into the process without interrupting or disturbing the process.

Accordingly, the present invention provides a strand starting assembly for a strand feeding assembly such as used in a strand chopping operation. The strand starting assembly comprises a starting cone and an idler assembly, made up of a plurality of individual idlers, which contact and cooperate with the conical surface of the cone to accelerate a strand. The strand to be accelerated is introduced be'tween'the idler assembly and the cone adjacent the head end of the cone. The strand,

as it is successively gripped between the idlers of the idler assembly and the conical surface, is urged toward operator greater leeway in selecting the rate of acceleration.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, FIG. 1 illustrates a strand chopping apparatus 20 which utilizes the strand accelerating assembly 22 of the present invention. While the invention is illustrated with and will be described in connection with a strand chopper utilized to make chopped glass strand, it is understood that the present invention can also be utilized in other high speed processes where it is necessary to accelerate a strand to the relatively high speed required for the particular process. 1

The strand chopping assembly 20 comprises a rotary chopper 24 and a backup roll 26 which cooperates with the rotary chopper to effect the chopping of the strand. A knurled pull roll 28 cooperates with the backup roll to feed a strand to the rotary chopper 24 and an oscillating strand guide 30 guides a strand from a bushing, package or other source to the backup roll and knurled pull roll. During the normal operation of the apparatus, the strand or strands pass through the guide 30 and between the knurled pull roll 28 and the backup roll 26. The knurled pull roll 28 and the backup roll grip and feed the strand or strands between the rotary chopper 24 and the backup roll 26 where they are chopped into strands ofdiscrete lengths. The chopped strands are then discharged in a horizontal direction through the discharge chute 32 of the apparatus where they are collected on a conveyer belt or other collection means (not shown).

The oscillating strand guide 30 comprises a pair of grooved rolls 34 and 36 between which the strand or strands 38 pass on their way from the source to the backup roll, and the knurled roll. Rolls 34 and 36 are rotatably mounted on brackets 40 and 42. Brackets 40 and 42 are bolted or otherwise secured to a frame 44 which is reciprocated by conventional means (not shown) in a horizontal plane in a direction transverse to thefline of travel of the strand or strands. With this arrangement the strand or strands are moved back and forth over the surface of the backup roll 26 so that the chopper 24 and the backup roll 26 will wear more evenly. l V i v The rotary chopper 24 is rotatably mounted on a car riage which permits adjustment of the rotary chopper 24 relative to the backup roll 26 by means of amicr'ometer adjustment assembly which is actuated by hand The'knurled roll 28 is rotatably mounted on one end of a link 48 which is pivotally mounted at its mid portion on a shaft 50'. The other end of the link is connected to a hydraulic piston assembly 52 so that by extending or retracting the piston rod of the hydraulic cylinder, the relative position of the knurled pull roll 28 and the backup roll 26 can be adjusted.

FIG. 2 illustrates a strand starting assembly 22 having a strand starting cone 54 which rotates with the backup roll 26. Both the backup roll 26 and the strand starting cone 54 are mounted on a shaft 56. The shaft 56 is rotatably mounted in and supported by bearings 58 which are, in turn, supported by the frame of the assembly. As shown, the inner end of the shaft 56 is provided with a shieve 60 which is connected by a drive belt to a motor. While this type of drive can be used with the present invention, it is contemplated that other forms of conventional drives can also be used to drive shaft 56.

The outer end of shaft 56 is provided with a threaded aperture 62 into which a retaining stud 64 is threaded to affix the strand starting cone to the shaft and mount the strand starting cone on the backup roll26. In the preferred embodiment, the strand starting cone 54 is a frustum with a conical outer surface 66 intermediate its base end and head end. For the purposes of this application, the term cone shall mean a cone, a frustum or other element having a generally conical surface for engaging a strand.

The base of the cone is provided with an annular flange 68 which is received within an annular groove 70 of the backup roll. This not only facilitates alignment of the starting cone 54 with the backup roll 26, but assures a smooth transition between the strand starting cone and the backup roll. The head end of the cone is provided with an annular flange 72 which defines a circular opening within which an end cap 74 is received.

The end cap 74 is a frustum with a conical surface which forms an extension of the conical surface 66. The end cap is provided with a boss 76 at one end which is received within the aperture defined by the flange 72. The retaining stud 64 passes through the end cap 74, through the hollow interior of the cone and is threaded into the aperture 62 of the shaft 60 to rigidly affix or clamp the strand starting cone to the backup roll so that they rotate together.

The embodiment of FIG. 3 differs from that of FIG. 2 in that the strand starting cone 78 of the strand starting assembly 22 is driven independently of the backup roll 26. In this embodiment, the shaft 80 of the backup roll 26 is hollow and a second shaft 82 is mounted within the shaft of the backup roll to support the strand starting cone 78.

The shaft 80 of the backup roll 26 is supported in a bearing 84 and is provided with a shieve 86 at its inner end. The shaft 80 is driven by a drive belt that is trained about the shieve and the output shieve of a motor.

The shaft 82 of the strand starting cone 78 is supported within the shaft 80 of the backup roll 26 by means of a pair of bearings 88 which permits the relative rotation of the backup roll relative to the strand starting cone. The inner end of the shaft 82 of the strand starting cone 78 is provided with a shieve 90 which is connected through a drive belt to a conventional variable speed drive means (not shown). The other end of the shaft 82 is provided with a tapered hub 92 to which the strand starting cone 78 is bolted so that the cone will rotate with the shaft 82.

The strand starting cone 78 is a frustum with a conical outer surface 94 intermediate its base and its head end. The base is provided with an end wall 96 having an aperture therein which is complimentary to and forms a force fit with the tapered surface of hub 92. The head end of the cone is provided with an annular flange 98 which defines a circular opening within which an end cap 100 is received.

The end cap 100 is a hollow cylindrical member which is provided with an annular flange 102 that is received within the aperture defined by the flange 98. The other end of the end cap is provided with an annular recess which has an end plate 104 therein. Studs 106 pass through the end plate 104, through the hollow interior of the end cap 100, and are threaded into apertures 108 of the shaft hub 92 to rigidly affix or clamp the strand starting cone to the shaft 82.

While the gap between the base of the strand starting cone and the backup roll'appears substantial, this is just for illustrative purposes. In practice, the gap is just sufficient to allow the strand starting cone and the backup roll to rotate independently without interference. While preferred forms of assembling and mounting the strand starting cones of FIGS. 3 and 4 have been shown, certain modifications and changes can be made to the assemblies without departing from the spirit and scope of the present invention.

As shown in FIGS. 1 and 4, the strand starting cones of FIGS. 2 and 3 are provided with a cone idler 110 which contacts the conical surface of the particular starting cone..The cone idler is generally positioned to contact the strand starting cone along a line about 40 to 60 from the point at which the strand first contacts the starting cone surface with the knurled pull roll 28 being located intermediate the point of introduction for the strand and the cone idler 110. While the amount of wrap for the strand can vary considerably depending on the requirements of a particular operation, the knurled pull roll must be located between the point of strand introduction and the idler to pick up-the strand. The cone idler 110 cooperates with the starting cone to grip a strand therebetween and initiate the acceleration of the strand. The cone idler 110 comprises a plurality of individual idler rolls 112 made of hard rubber or similar materials and mounted'on a common shaft 114 which .extends parallel or substantially parallel to the conical surface of the starting cone. The idler rolls 112 readily conform to the cone when subjected to light pressure and can be replaced individually when worn. The individual idler rolls 112 must be free to rotate independently of each other since the surface speed of the cone differs from point to pointwith the surface speed increasing from the head of the cone to the base portion of the cone.

As shown in FIG. 4, the cone idler 110 is carried by a bracket 116. The bracket 116 comprises an elongate frame member 118 with a support arm 120 depending from each end. The ends of shaft 114 are supported in the arms 120 with the shaft extending parallel to the conical surface of the strand starting cone. The frame member 118 is provided with a longitudinally extending flange 122 which is rigidly affixed to a clevis 124 of the cone idler support frame 126.

The cone idler support frame 126 comprises a horizontally extending tubular frame member 128 and a vertically extending tubular frame member 130. Tubular frame member 128 is welded or otherwise secured at one end to the main frame of the strand chopping assembly. The other end of the tubular frame member 128 is welded or otherwise affixed to the upper end of tubular frame member 130 and supports that frame member.

A double-acting air cylinder 132 is mounted on the upper end of member 130. A piston rod 134 of the air cylinder 132 extends down into tubular frame member 130 and is secured to a multi-section shaft 136 which is welded to clevis 124.

The air cylinder 132 is connected to a four-way valve or similar control means through

pneumatic lines

138 and 140 which communicate with the air'cylinder 132 on either side of the air cylinder piston. The valve vents one side of the piston while supplying pressurized air to the other side of the piston. THe valve is preferably actuated by a foot switch to lower the cone idler into operating position. When the foot switch is not depressed, the upper side of the piston is vented and the underside of the piston is pressurized to position the cone idler above and out of contact with the strand starting cone in an inoperative position. The multi-sectional shaft 136 is provided with a cam follower 142 which is guided by a cam 144 to prevent the shaft from twisting and maintain the cone idler 110 in proper alignment with the strand'starting cone. The cam 144 comprises a pair of vertically extending blocks 146 which are joined by a plate 148 to form a vertically extending channel. The plate 148 is.welded or otherwise affixed to the tubular frame member 130 and is provided with a vertically extending slot ISO-through which the cam follower 142 projects. The cam follower 142 has a head 152 at one end which slides within and contacts the sides of the channel formed by the block 146. The other end of the follower is threaded into and supported by the multi-section shaft 136 with a spacer 154 assuring that the head 152 of the follower and the plate 148 of the cam do not interfere with each other.

In operation, a strand is passed'through the oscillating strand guide 30. The foot switch is depressed bringing the cone idler 110 into firm contact with the surface of the strand starting cone 54 or 78. The strand is then wrapped part way about'the cone (typically about 40 to 60) and inserted between thelower end of the cone idler 110 and the strand starting cone 54 or 78. Since the oscillating strand guide is centeredrelative to the backup roll 26 and the knurled pull roll 28, the strand is urged toward the backup roll 26. As the strand progresses toward the base of the strand starting cone, successive idler rolls 112 of the cone idler 110 cooperate with the

conical surface

66 or 94 of the strand starting cone to grip the strand and accelerate the speed of the strand. When the strand reaches the base of the idler cone, the line of travel of the strand from the oscillating strand guide 30 to the cone idler 110 causes the strand to pass between the backup roll 26 and knurled-pull roll 28 whereby the backup roll and knurled pull roll pick up the strand and feed it between the backup roll and the blade roll or chopper24 where it is chopped and discharged. Once the strand is picked up by the backup roll 26 and the knurled pull roll 28, the footswitch is released and the cone idler 110 is moved out of contact with the starting cone.

In an operation where there are a plurality of strands, this method can be utilized to start the individual strands. If any of these strands'should break, the individual strand can be reintroduced between the cone idler 110 and the strand starting cone 54m 78. There, the strand is automatically accelerated to the proper speed and moved up the cone to a point where it is picked up by the backup roll and the kunrled pull roll.

With the embodiment of FIG. 4, wherein the starting cone 78 is driven independently of the backup roll 26, the speed of the strand starting cone 78 can be increased while the strand is held at the end cap of the cone where it is gripped betweenthe end cap and an idler or other suitable means for maintaining the strand in contact with the end cap while the cone is accelerated. The idler is supported by suitable means such as an extension of bracket 1 16. This type of apparatus is only necessary where the final desird speed is so high that the cone lengthsto produce the desired strand acceleration and entry speed become awkward or impractical. As with the other embodiment, because of the angle between the oscillating strand guide 30 and the point of introduction for the strand between the idler and the cone, the strand automatically proceeds up the incline of the cone after it is released with its velocity increasing uniformly. Just before the strand leaves the influence of the cone idler 110, it is pinched between the knurled pull roll 28 and the backup roll 26. At this point it has reached its final velocity and moves across the backup roll to its final position in alignment with the strand guide 30 and the blade roll What we claim is:

1. A strand feeding assembly comprising a feeding means for gripping and pulling a strand that includes a roll, means for aligning and guiding the strand to the feeding means, and a strand starting assembly, the strand starting assembly comprising:

a. a starting cone, the starting cone being rotatably mounted on an axis corresponding to the axis of the roll, means for rotating the starting cone, the starting cone having a base end and a head end with a conical surface extending between the base end and the head end, the base end of the starting cone being adjacent the roll, the base end having a diameter approximately equal to the diameter of the roll;and

b. idler means, the idler means being in contact with the conical surface of the starting cone whereby the idler means is rotated by the starting cone, and the idler means comprising a plurality of idlers which cooperate with the conical surface of the starting cone to successively grip a strand as the strand accelerates and progresses from the head end to the base end of the starting cone.

2. The strand feeding assembly of claim 1 wherein the guide means and the idler means are positioned relative to each other in such a manner that when the strand is gripped between the idler means and the starting cone at the base end of the cone, the'strand is picked up by the feeding means.

3. The strand feeding assembly of claim 2 wherein the point of introduction of the strand means to the roll is about 40 to 60 from a line of contact between the idler means and the conical surface of the starting cone.

4. The strand feeding assembly of claim 2 wherein the guide means is aligned with the feeding means and a source of the strand.

5. The strand feeding assembly of claim 1 wherein means for rotating the starting cone is independent of means for driving the feeding means.

6. The strand feeding assembly of claim 1 wherein the starting cone is affixed to the roll of the feeding means and means for rotating the starting cone also drives the feeding means.

7. The strand feeding assembly of claim 1 wherein the feeding means comprises the roll and a pull roll.

8. The strand feeding assembly of claim 7 wherein the point of introduction of the strand to the roll is about 40 to 60 from the line of contact between the idler means and the conical surface of the starting cone and the pull roll is located intermediate the point of introduction and the idler means.

9. The strand feeding assembly of claim 1 wherein the feeding means is a component of a strand chopping assembly.

10. A strand accelerating assembly for bringing a strand up to a proper speed for a process comprising a. a cone, the cone having a base end and a head end with a conical surface therebetween, the cone being rotatably supported about an axis passing through the base end and the head end;

b. means for rotating the cone about the axis;

c. idler means in contact with the conical surface of the cone whereby the idler means is rotated by the cone, and the idler means comprising a plurality of idlers which cooperate with the conical surface of the cone to successively grip and accelerate a strand introduced between the idler means and the conical surface as the strand progresses from adjacent the head end to the base end of the cone where the strand can be picked up by other apparatus.

11. The strand accelerating assembly of claim 10 wherein means is provided for disengaging the idler means from the conical surface.

12. The strand accelerating assembly of claim 10 wherein means is provided to urge the strand toward the base end of the cone.

13. A method of accelerating a strand comprising:

a. introducing a strand between an idler assembly comprising a plurality of idlers and a conical surface of a rotating cone adjacent a head end of the cone; and

b. urging the strand along the conical surface toward a base of the cone whereby the idlers cooperate with the conical surface of the cone to successively grip and accelerate the strand as the strand progresses from the head end to the base of the cone.

Claims

1. A strand feeding assembly comprising a feeding means for gripping and pulling a strand that includes a roll, means for aligning and guiding the strand to the feeding means, and a strand starting assembly, the strand starting assembly comprising: a. a starting cone, the starting cone being rotatably mounted on an axis corresponding to the axis of the roll, means for rotating the starting cone, the starting cone having a base end and a head end with a conical surface extending between the base end and the head end, the base end of the starting cone being adjacent the roll, the base end having a diameter approximately equal to the diameter of the roll; and b. idler means, the idler means being in contact with the conical surface of the starting cone whereby the idler means is rotated by the starting cone, and the idler means comprising a plurality of idlers which cooperate with the conical surface of the starting cone to successively grip a strand as the strand accelerates and progresses from the head end to the base end of the starting cone.

2. The strand feeding assembly of claim 1 wherein the guide means and the idler means are positioned relative to each other in such a manner that when the strand is gripped between the idler means and the starting cone at the base end of the cone, the strand is picked up by the feeding means.

3. The strand feeding assembly of claim 2 wherein the point of introduction of the strand means to the roll is about 40* to 60* from a line of contact between the idler means and the conical surface of the starting cone.

8. The strand feeding assembly of claim 7 wherein the point of introduction of the strand to the roll is about 40* to 60* from the line of contact between the idler means and the conical surface of the starting cone and the pull roll is located intermediate the point of introduction and the idler means.

10. A strand accelerating assembly for bringing a strand up to a proper speed for a process comprising a. a cone, the cone having a base end and a head end with a conical surface therebetween, the cone being rotatably supported about an axis passing through the base end and the head end; b. means for rotating the cone about the axis; c. idler means in contact with the conical surface of the cone whereby the idler means is rotated by the cone, and the idler means comprising a plurality of idlers which cooperate with the conical surface of the cone to successively grip and accelerate a strand introduced between the idler means and the conical surface as the strand progresses from adjacent the head end to the base end of the cone where the strand can be picked up by other apparatus.

13. A method of accelerating a strand comprising: a. introducing a strand between an idler assembly comprising a plurality of idlers and a conical surface of a rotating cone adjacent a head end of the cone; and b. urging the strand along the conical surface toward a base of the cone whereby the idlers cooperate with the conical surface of the cone to successively grip and accelerate the strand as the strand progresses from the head end to the base of the cone.