US2577013A

US2577013A - Machine for stretching and coating webs of sheet material

Info

Publication number: US2577013A
Application number: US50934A
Authority: US
Inventors: Benjamin D Hyde
Original assignee: BB Chemical Co
Current assignee: BB Chemical Co
Priority date: 1948-09-24
Filing date: 1948-09-24
Publication date: 1951-12-04
Anticipated expiration: 1968-12-04

Description

Dec. 4, 1951 B. D. HYDE 2,577,013

MACHINE FOR STRETCHING AND COATING WEBS OF SHEET MATERIAL Filed Sept. 24, 1948 7 Sheets-Sheet l rs 'r [771/ e niol Bery amin D. Hyde B. D. HYDE Dec. 4, 1951 MACHINE FOR STRETCHING AND COATING WEBS OF SHEET MATERIAL 7 Sheets-Sheet 2 Filed Sept. 24, 1948 Dec. 4, 1951 HYDE 2,577,013

- MACHINEFOR STRETCHING AND COATING WEBS OF SHEET MATERIAL.

Filed Sept. 24, 1948 7 Sheets-Sheet 5 Inventor B. D. HYDE 2,577,013

MACHINE FOR STRETCHING AND COATING WEBS OF SHEET MATERIAL Dec. 4, 1951 '1 Sheets-Sheet 4 Filed Sept. 24, 1948 Intern/07 Benjamin D Hyde Dec. 4, 1951 B, D, HYDE 2,577,013

MACHINE FOR STRETCHING AND COATING WEBS OF SHEET MATERIAL Filed Sept. 24, 1948 7 Sheets-Sheet 5 Inve nzor Ben /42mm .D Hyde By hr Affor'ne Dec. 4, 1951 B. D. HYDE 2,577,013

MACHINE FOR STRETCHING AND COATING WEBS OF SHEET MATERIAL Filed Sept. 24, 1948 7 Sheets-Sheet 6 [nve n50? Benjamin D [:{ycle A a 6 I B. D. HYDE Dec. 4, 195] MACHINE FOR STRETCHING AND COATING WEBS OF SHEET MATERIAL 7 Sheets-Sheet 7 Filed Sept. 24, 1948 [aveniop Ben czmzhp Hyde Patented Dec. 4, 1951 MACHINE FOR STRETCHIN G AND COATING WEBS OF SHEET MATERIAL Benjamin D. Hyde, Cambridge, Mass., assignor to B. B. Chemical 00., Boston, Mass., a corporation of Massachusetts Application September 24, 1948, Serial No. 50,934

11 Claims.

- This invention relates to machines for treating sheet material, and is herein illustrated as embodied in a machine for stretching a web of material laterally and, at substantially the same time, applying'a coating to the material between the opposite rows of tenter clips of the stretching or tentering device.

In the manufacture of insoles for use in shoes, and especially those which are employed in welt shoes, it has been common for many years to utilize a reinforcing material of duck or canvas which is attached to the material of the insole by adhesive. Various forms of adhesive have been employed'and some of these are thermoplastics which are dried and then are reactivated by means of heat as they are applied to the insoles. Reinforcing material of this type is commonly sold to the shoe manufacturer in the form of coated strips. These strips may be wide enoughto cover the whole width of the insole or when employed in the so-called Griswold process they may be much narrower strips. In the making of the strips a web of material is coated and the coating is dried and the web is subdivided into strips by slitting. The adhesives used for this type of material are rather heavy and viscous and in order that the coating may be applied evenly throughout the length of the strip it hasbeen a custom for a long time to coat the web while under tension longitudinally. However, there has been employed by textile manufacturers a machine for stretching a web transversely which is called a tentering machine and which employs a series of clamps or tenter clips linked together in the form of a chain. Two of these chains, associated with opposite sides of a web, are guided by spaced rails which gradually diverge from one another so that a tension is imparted to the material transversely thus holding it smooth and in fixed position heightwise. The gain in width of the material is retained inasmuch as the tension is maintained while the coated web is carried through a drying chamber until the adhesive becomes nontacky. The web is then slit to form strips and the strips wound in rolls.

The application of adhesive coating material to sheet material while in a tentering machine is accompanied by great difliculty because of the danger of the transfer of portions of adhesive to the moving parts of the tenter clips, with the result that it has" been necessary to clean the machine at frequent intervals. This cleaning is especially diflicult when a drying chamber is employed because of the fact that the adhesive is more or less baked onto the grippers of the clips and because there are frequently a thousand or more clips involved. Accordingly, an object of the invention is to provide an improved machine for treating sheet material which will avoid these and similar difliculties.

One important feature of the invention resides in the combination with tentering mechanism of coating mechanism which is disposed beneath the stretched web. Thus the daubing of the tenter clips can be readily avoided, especially'by restricting the coated area to the space between opposite rows of tenter clips.

In the continuous use of such a machine it is frequently necessary to stop the drive of the machine for various reasons such as to permit the operators to take oii the completed rolls of coated cloth. If the coating device were allowed to remain in contact with the web of material while the latter is stopped for several minutes then there would be grave danger because of the sticking of the applying device to the web and furthermore, a portion of the web opposite the coating device at that time would be rendered useless because of the thickened layer of coating material deposited thereon. In accordance with a feature of the invention, therefore, the applying devices, such as applying rolls, are arranged for vertical sliding movement. They are counterbalanced and provision is made for operator control so that the rolls may be quickly moved to an inoperative position out of contact with the web when the machine is stopped.

Another feature of the invention resides in the arrangement of a plurality of coating devices which are supported at their ends by the chainguiding rails of the tentering machine. The arrangement is such that successive rolls have alternate outer ends disposed closely adjacent to the tenter clips while mid-portions of these rolls overlap. The rolls are supported for lateral adjustment with the rails and as a result no fine adjustment is necessary when it is desired to change the spacing of the rails as when diflerent widths of material are to be treated.

The illustrated machine utilizes applying rolls which are driven in such a direction that the coat-applying portion moves oppositely to the web of material. A surplus of material is thus applied and doctor bars are mounted beneath the web following the applying rolls and arranged for adjustment toward and away from the web so as to control the depth of the coating by causing the unused coating material to drain back into an underlying receptacle. Another important feature of the invention resides in the provision of shields between the ends of the doctor bars and the chains of the tentering machine and the utilization of a scraper cooperating with that end of a roll which is adjacent to the tenter clips to control the amount of material carried upward by the end surface of the roll thereby to prevent the coat ng material from being applied to the tenter clips.

These and other features of the invention will best be understood from the following description taken in connection with the accompanying drawings. in which Fig. 1 is a side elevation of that portion of a tentering machine, with its coating apparatus, which precedes the drying chamber;

Fig. 2 is a plan view of the corresponding portion of the machine;

Fig. 3 is an enlar ed side elevation of that portion of the machine which includes the coating apparatus;

Fig. 4 is a still lar er side elevation of one coating roll and a sliding support therefor;

Fi s. 5 and 6 are enlarged vertical sections at the opposite ends of the coating-applying roll shown in Fig. 4 and these views are taken on the section lines V-V and VI-VI in Fig. 2;

Fig. is a similar vertical section on the line VII-VII in Fig. 2 to show a portion of a doctor bar and an adiacent shield as well as the adjusting mechanism for the doctor bar;

Fig. 8 is an invert d plan view of a portion of this adjusting mechanism;

Fi 9 is an an ular dia rammatic view of the coating devices to show their relation to each other and to the web of material; and

Fi 10 is a vertical section transversely of one of the doctor bars.

In general the tentering portion of the machine comprises a pair of longitudinally disposed grooved tenter rails i0. H (Figs. 2 and 6) in each of which are guided endless chains composed of a series of tenter clips [2, the opposite ends of the e clins having notches M (Fig. 4) and projections l6 joined by pivot pins I8 in a series of knuckle joints. At opposite ends of the rails, these chains pass around sprockets 20, and at the delivery end of the machine, which is not shown in the drawings, power is supplied to the sprockets to drive the chains. The rails have grooves 2| bounded by flanges 23 and cover plates 25 are provided to hold the chains in the grooves. These rails III, II are adjustably supported on a series of pedestals 22 (Fig. 1) on which there are mounted transverse guides 24 and adjusting screws 26 (Fig. 2) thus permitting the divergence of the rails, as well as their separation for the different widths of material, to be readily adjusted.

Adjacent to the ingoing end of the machine a bolt of cloth 28 is supported on a table and the web 29 passes through a series of straightening

rods

30, 32 before it is received by the tenter clips as they pass around the sprockets 20. Also at this end circular plates 34 are provided above the sprockets These plates engage the inner side of the upstanding finger 3B of a pivoted gripper 38 (Figs. 4 and 6). One gripper is provided on each of the tenter clips and is opened as its finger en ages the plate 34. These opener plates 34, by tilting up the grippers 38 lift the blades 39 at the lower end of these members permitting the insertion of the edges of the web between the blades 39 and a stationary jaw 40 on each clip. Many sorts of tenter cl p are available but the kind illustrated is also provided with controllers 42 which are loosely pivoted plates having a cam slot for engagement with a pin 44 on a projection of the gripper. The edge of the cloth is first inserted far enough to underlie the end of the corresponding controller and then as the web is drawn farther into the machine the web is gradually pulled back until the controller drops off the edge of the web and permits the gripper blade 39 to wedge itself against the margin of the cloth. In this condition the grip is so firm that a substantial amount of lateral tension may be imparted to the web as the clips are guided by the grooves 2| and held against the flanges 23 of the rails l0, ll.

It will be seen that the web of material is stretched laterally by reason of the divergence of the rails and held firmly in a substantially horizontal plane as it approaches the coating apparatus which embodies a pair of driven. coating-apply rolls 50, 52 (Figs. 2, 3 and 9) acting successively to pick up material from a tank 54 which lies beneath them and to apply it to the underside of the web without coating the clips. Power for driving these rolls so that their upper sides move in a direction opposite to the direction of movement of the cloth is furnished by a motor 56 (Fig. 2) joined through a speed reduction mechanism 58 and a driving chain 60 to a sprocket 62 on the end of the roll 52. At the opposite ends of the rolls (Fig. 3) are

sprockets

64 and 86 interconnected by a chain 88 which causes the two rolls to be turned in the same direction.

The tank 54 is mounted on a hydraulic hoist 10 (Fig. 1) to facilitate its removal for cleaning or the like when raised to operative position brings the level of the adhesive up to cover the lower portion of each roll. A filling spout 12 (Fig. 2), which leads to the tank 54, makes it easy to replace the used adhesive.

At each side of the machine adjacent to the coating apparatus and attached to the rails 10, II are supports 14 (Fig. 6), to the tops of which there, are bolted uprights 16, 18 (Fig. 5) extending above the ends of the rolls. Each of the rolls has an axial shaft 80, the opposite ends of which are carried in

bearings

82, 84 supported upon pieces of angle iron 85 which are slidable vertically between

guides

86 and 88. The limit of downward movement is determined by stops 90. The rails and supports are cut away at 9| (Figs. 4, 5 and 6) to permit this movement of the shafts 80. Collars 92 are associated with the inner adjacent ends of the bearings and are clamped to the shaft by setscrews while at the left end of the shaft, as viewed in Fig. 6, is the sprocket 62 and at the right end of the shaft. as viewed in Fig. 5, there is the sprocket 64 which may also be held in position by setscrews. The sprocket 64 is splined on the shaft and when it is desired to adjust the spacing of the rails l0 and II it is only necessary to loosen the setscrews adjacent to the bearing 84 arid to let the shaft move to the left in Fig. 5 with the rail ill to the required distance, then to reclamp the sprocket 64 and the collar 92 beside the bearing. A similar arrangement, reversed end for end, is provided for the roll 50.

It will be noted that there is a substantial space between the end of the roll 52 and the tenter clips associated with the rail ll while at the opposite side of the machine the end of the roll 52 is closely adjacent to the tenter clips which are associated with the rail I0. At this end of the roll a scraper 94 has a body portion depending from the inner flange of the rail I and an upturned operative portion 93 which is associated with the upgoing side of the edge of the hollow cylinder which provides the periphery of the roll, as may be seen from an inspection of Fig. 4. By this arrangement the carrying of any substantial quantity of cement upward by the end of the roll is prevented and thus its transfer to the tenter clips is prevented. This action is also aided by the setting of the end partitions 98 of the rolls inwardly of the ends of the peripheries thereof.

An arrangement for lowering the rolls comprises a transverse shaft I00 having at its right hand end (Figs. 3 and 5) a handle I02, this shaft being mounted in bearings at the tops of the uprights 16 and I8. The roll 52 and its bearings and slides 85 are counterbalanced by springs I04 extending to a rigid member. The adjacent .ends of these springs are joined to chains I06 (Fig. 4) extending over sprockets I08, H0 at the opposite ends of the shaft I00 and these chains are connected at their lower ends to angle pieces I I2 which are bolted to the tops of the

bearings

82, 84. Similar springs I20 (Fig. 3) are connected by similarly mounted chains I22 to the bearings at the ends of the roll 50. These latter chains handle I02 which is connected to the shaft I00. This enables the operator, upon learning that the machine is to be stopped, to immediately lower both coating rolls out of contact with the underside of the web 29 to the limit permitted by the stops 90, thus preventing the web from being stuck to the rolls in case the period of rest is long enough for the adhesive to dry, and in any event preventing the formation of an uneven deposit of cement at the stopping point.

Associated with and following each of the coat-- ing rolls are doctor bars I 30, I32 (Fig. 9) which have rounded upper edges (Fig. 10), and which scrape off the surplus material and thus control Too thick a bar will'fail to drive the adhesive suf ficiently far into the fabric to obtain good adhesion qualities in the finished strip; The doctor bar I30 is arranged so that it may beset in various heightwise positions by bolts in a series of holes but inasmuch as the web is to be given its second application of coating material by the roll 52, a fine adjustment is not required. However, it is found desirable to provide a convenient way of accurately determining the position of the last-- encountered doctor bar I32 and to this end it is carried at opposite ends by angle bars I34, which are tiltable uponstuds such as that shown at I36 (Fig. 7) threaded in the rails, under the control of vertical screws I38 threaded through the other ends of these bars. Each vertical screw I38 is mounted for 'rotation in a supporting plate I40 (Fig. 8) carried by the underside of the rails and is prevented from heightwise movement with respect to this plate. on the lower end of each screw is a worm gear I42 which is associated with a worm I 44 carried by a rod I46 which extends to the outside of the machine and is provided with a hand wheel I50.

At the ends of the doctor bars it is important to prevent the unused cement from being deposited on the adjacent tenter clips and shields I52 are, accordingly, mounted on the rails at the ends of each bar. As best shown in Fig. 7, these shields are bent inwardly and then upwardly so that their upper edges contact the underside of the web directly at the ends of each doctor bar. Cooperating in the control of the quantity of cement by the doctor bar I32, is a grooved holddown bar I54 (Figs. 9 and 10), which is adjustably supported upon a bridge plate I56 carried by the cover pieces I58 which are associated with each of the rails. In combination with this, a light weight I60, resting on the web and prevented from longitudinal movement therewith by contact with the holddown I54, may be utilized. A similar holddown device I62 may be mounted between the coating apparatus and the drying chamber to avoid any flutter of the web 29 such as may be caused by the circulating air escaping through the entrance of the drying chamber (not shown).

In the operation of the machine the web 25 will be threaded over the straightening

rods

30, 32 and then guided into the open clips as they pass around the sprockets 20. The lateral spacing between the rails I0 and II has previously been adjusted by means of the right and left screws 26 and the progressing web will be tightly grasped by the clamping

members

38, 39 of the tenter clips and stretched laterally as it approaches the coating rolls and 52. It will be recalled that these rolls rotate oppositely to the direction of movement of the web and that the thickness of the coating is controlled by the adjustment of the scraper bars I30 and I32. No adhesive will be deposited upon the tenter clips because of the shields I52 at the ends of the scraper bar and the scrapers 96 at those ends of the rolls which lie adjacent to the clips. Adjustmerit of the spacing between the rails is simplifled by the utilization of the overlapping, offset rolls 50 and 52 and if the machine is to be stopped i the operator can manipulate the handle I02 and drop the rolls away from the work. It will be remembered that these rolls are continuously counterbalanced by springs I04 and I20 so that with little effort the rolls may again be lifted into contact with the web of material when the machine is again started.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a machine for treating sheet material, means including tentering clips for supporting and conveying a web of the material in a substantially horizontal path and for holding it under lateral tension, a coating roll contacting with the under side of said web, the work-contacting portion of said roll being driven in a direction opposite to the direction of movement of the web,

a doctor bar contacting with a horizontal portion of the under side of the web beyond the roll to control the thickness of the applied coating, and means for protecting the clips adjacent to the doctor bar.

2. In a machine for treating sheet material, chains having tenter clips gripping the opposite edges of the material, guide means cooperating withsaid chains to stretch the material laterally as it progresses in a substantially horizontal direction, means for applying a coating of heavy, Wiscous adhesive to the whole of the surface of the under surface only of the horizontal run of the material between the opposite rows of tenter clips, and means for protecting said clips adjasaid chains to stretch the material laterally as it 10 progresses in a substantially horizontal direction, means for applying a coating of viscous adhesive I to the'under side of the horizontal run of the material between the opposite rows of the tenter =clips, and web-contacting shields to prevent the spreading of the viscous adhesive to the tenter clips near the point of application of the adhesive to the sheet material.

4. In a machine for treating sheet material,

tenter rails, means carried by said rails for 'sup-. 2

porting a web of said material, a coating roll ,adapted to engage the under surface of the web. bearings for said roll mounted on the rails for vertical sliding movement, means for counterbalancing the weight 0! said roll, and manually operated means for moving the roll to a position "out of contact with the web when the machine is stopped. i

5. In a machine for treating sheet material,

7 rails receiving and guiding chain-forming tenter.

clips for supporting a web of said material and stretching it laterally, a plurality of coating rolls .arranged to contact the under side of the web between the clips, bearings for said rolls slidably supported on the rails for up-and-down movement, individual counterbalancing devices for said bearings and the rolls rotatable therein, posii tive interconnecting means between said counterbalancing devices, and a manually operated member for moving said interconnecting means to cause the two rolls to be lowered out of contact with the web when the machine is stopped.

6. In a tentering machine, chains bearing tenter clips engaging the opposite margins of a web of material, chain guiding rails supported for adjustment relatively to one another laterally of the web, and a pair of cement applying rolls positioned one after the other to coat the under side of the web, one of said rolls being supported for adjustment laterally of the web, each of said rolls having one end positioned closely adjacent to the clips and its other end spaced therefrom in any position of the rails.

7. In a tentering machine, chains bearing tenter clips engaging the opposite margins of a web of material, chain-guiding rails supported for adjustment relative to each other in a direction laterally of the web, a pair of cement-applying rolls positioned one after the other to coat the under side of the web, said rolls each having one end positioned closely adjacent to the clips and its other end spaced therefrom, and bearings for said'rolls carried by said rails and slidable axially on the roll shafts to permit the adjustment of the rolls with the rails to maintain a fixed relationship between one end of each of the rolls and" their adjacent rails.

8. In a tentering machine, chains having tenter clips engaging the opposed edges or a web of .8 a material, rails for guiding said chains, said rails being supported for lateral adjustment and positioned to cause the chains to stretch the web laterally,-means for applying coating material to the under side of said web between said chains, a scraper bar for engaging the under side of the web for controlling the quantity of material retained upon the web, and a shield interposed between at least one end of the said scraper bar and the adjacent chain.

9. In a tentering machine, chains having tenter clips, rails for guiding said chains to cause the web to be stretched laterally, means for applying coating material to the under side of the web, a scraper bar having a rounded upper edge engaging the under side of the web to control the thickness of the material retained thereon. means for adjusting said bar toward and away from the work, and a shield carried by said rail positioned between the end of the scraper bar and the clips on the chain thereby to contact the web to keep the coating material away from the clips.

10. In a machine for treating sheet material, means for supporting a web of said material, a coating roll for applying coating material to the under side of said web, said roll comprising a hollow cylinder having and partitions each inset inwardly from the adjacent end edge of said cylinder, a receptacle for supplying coating material and in which said rolldips, and a scraper having a depending body provided with a resilient upturned blade cooperating with the upgoing side of the end edgeof the roll.

11. In a tentering machine, a chain having tenter clips engaging one edge of a web of material, a coating roll engaging the under side oi. said web, means for supplying coating material to said roll, means for rotating said roll to cause its upper surface to move in a direction opposite to the direction of the web, a scraper-bar positioned to engage the under side of the web beyond the point of contact of the roll therewith, a shield also engaging said web between the end of said barand the tenter clips, and a scraper coacting with the end of the roll adjacent to said clips to control the amount of coating material carried upward by the end surface of the roll thereby to prevent coating material being applied to the 0 tenter clips by said roll.

BENJAMIN D. HYDE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 'Hawley et al. Jan. 6, 1948