US3649144A

US3649144A - Device for forming belt loop blanks

Info

Publication number: US3649144A
Application number: US83823A
Authority: US
Inventors: Louis William Breck Jr
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-10-26
Filing date: 1970-10-26
Publication date: 1972-03-14
Anticipated expiration: 1989-03-14

Abstract

A machine has been provided for automatically hot crimping a fabric tube or string containing thermoplastic material either as part of the fabric or as thermoplastic insert in said tube; from this tube the belt loop blanks are formed by crimping appropriate length of the tube. The machine which accomplishes this is comprised of a heated top die member vertically reciprocating in a guide means therefor; a heated, stationary bottom die member; a pair of crimping die members horizontally and each to the other oppositely reciprocating and operatively engaged with said bottom die member means for urging downwardly said top die members operatively interconnected to said means for urging downwardly said top die member; means for retracting upwardly said top die member; means for retracting upwardly said top die member including means for limiting upward retraction thereof; means for limiting upward retraction thereof; means for withdrawing outwardly said crimping die members operatively interconnected to the means for retracting upwardly said top die member; means for feeding said tube into a crimping position, said means for feeding being operatively interconnected with said means for retracting upwardly said die; means for severing a crimped belt loop blank said means for severing being operatively interconnectable with means for feeding said string; and, means for automatically cycling said machine including means for monitoring the proper operation thereof.

Description

United States Patent Breck, Jr.

[54] DEVICE FOR FORMING BELT LOOP BLANKS [72] Inventor: Louis William Breck, Jr., 8 Joe Turner Court, El Paso, Tex. 79915 [22] Filed: Oct. 26, 1970 [21] Appl. No.: 83,823

[56] References Cited UNITED STATES PATENTS 3,095,630 7/ 1963 Pittman ..264/ 168 X 3,129,485 4/1964 Shattuck ..28/ 1.2 3,499,076 3/1970 Martin et a1. ..264/168 X Primary Examiner-Robert L. Spicer, Jr. Attomey-Curtis, Morris & Safford 5] Mar. 14, 1972 [57] ABSTRACT A machine has been provided for automatically hot crimping a fabric tube or string containing thermoplastic material either as part of the fabric or as thermoplastic insert in said tube; from this tube the belt loop blanks are formed by crimping appropriate length of the tube. The machine which accomplishes this is comprised of a heated top die member vertically reciprocating in a guide means therefor; a heated, stationary bottom die member; a pair of crimping die members horizontally and each to the other oppositely reciprocating and operatively engaged with said bottom die member means for urging downwardly said top die members operatively interconnected to said means for urging downwardly said top die member; means for retracting upwardly said top die member; means for retracting upwardly said top die member including means for limiting upward retraction thereof; means for limiting upward retraction thereof; means for withdrawing outwardly said crimping die members operatively interconnected to the means for retracting upwardly said top die member; means for feeding said tube into a crimping position, said means for feeding being operatively interconnected with said means for retracting upwardly said die; means for severing a crimped belt loop blank said means for severing being operatively interconnectable with means for feeding said string; and, means for automatically cycling said machine including means for monitoring the proper operation thereof.

19 Claims, 13 Drawing Figures Patented March 14, 1972 1 0 Sheets-Sheet 1 R. m. m V m L WILLIAM BRECK, Jr.

ATTORNEYS Patented March 14, 1972 3,649,144

1 0 Sheets-Sheet 2 i H INVENTOR.

35 L.WILLIAM eascxm.

l ATTORNEYS Patented March 14, 1972 10 Sheets-Sheet 5 INVENTOR. L. WILLIAM BRECK. Jr.

ATTORNEYS Patented Mmh 14, 1972 10 Sheets-Sheet 4 QVENTOR. L. WILLIA BRECK, Jr.

ATTORNEYS Patented March 14, 1972 3,649,144

1 0 Sheets-Sheet 5 INVENTOR. L. WILLIAM BRECK. Jr.

ATTORNEYS Patented March 14, 1972 I 3,649,144

1 0 Sheets-Sheet 6 INVENTOR. L. WILLIAM BRECK, Jr.

ATTORNEYS Patented Mai-ch 14, 1972 I 3,649,144

10 Sheets-Sheet '7 INVENTOR. L. WILLIAM BRECK. Jl.

ATTORNEYS Patented March 14, 1972 1 0 Sheets-Sheet 8 INVENTOR. L WILLIAM BRECK, Jr.

ATTORNEY Patented March 14, 1972 10 Sheets-Sheet 10 wmw INVEN'IOR. L. WILLIAM BRECK, Jr.

ATTORNEYS DEVICE FOR FORMING BELT LOOP BLANKS This invention relates to a device for hot crimping of a fibrous thermoplastic material; more particularly, this device relates to hot crimping of a sewn ribbon or tube of fabric from which belt loops are formed and allows either production of an individual belt loop blank or the formation ofa continuous string ofloosely joined belt loop blanks.

In producing garments, it has been the desideratum in the industry to minimize as much as possible the labor component associated with each individual garment part. However, heretofore, the proposed solutions for these labor minimizing steps have been unduly costly or economically prohibitive from the standpoint of design of mechanical means or machines, machine controls, or machine operations. Consequently, highly complex machines have been suggested for performing tasks which have been performed by unskilled operators. As a result, the justification for replacing manual labor with complex machinery has not been demonstrated.

A primary consideration in any labor saving device used in the garment industry is the employment of an extremely simple or uncomplicated machine which can perform tasks manually performed or machinery which can perform endlessly repetitive functions in a very simple manner and highly reliably. Moreover, it is advantageous that the produced item can be used in other machines designed to supplement or supplant manual labor.

Thus, in producing garments such as mens pants or other equivalent garments requiring a support means for belts, loops have been formed generally from the same fabric from which the garment has been made. These loops are narrow strips of fabrics sewed together at the side which is exposed to the belt but not to the observer.

A previous procedure for forming these belt loops has consisted of first, sewing together the fabric in a continuous tube or tape and then severing from the tape a blank of appropriate length from which the belt loop is formed. Thereafter, the belt loop blank is laid on the garment, one end of the blank tacked to the garment, the belt loop bent over the tacked section and then the top part of it folded onto itself and the hidden section and the front section thereof tacked to the garment. As consequence of this procedure, if the hidden ends of the bent belt loop are squarely cut, these have a tendency to ravel and expose loose strands. Moreover, the squarely cut end flatens on pressing and is rather noticeable. This causes unsightly appearance to the garment signifying in the mind of a purchaser improperly finished goods. The obvious alternative has been to first sew each end of the belt loops to that the fiber unraveling will not take place.

As it can well be appreciated, the sewing of each end of each individual belt loop blank introduces a considerable labor component into the production of this seemingly insignificant item.

It has now been discovered that if a previously sewn string of belt loop forming material is crimped in a novel fashion, the unsightly appearance'of the squarely cut belt loop blank can be avoided, the appearance of the belt loop blank or the belt loop in its finally tacked position considerably improved in that the loose strands can be eliminated and the roundly finished cut does not expose the end of the belt loop blank. Thus, the quality of the goods is improved to such a degree that it matches the best handmade or best finished article available at a fraction of cost thereof. Moreover, the production of these belt loop blanks has been achieved by means of a novel machine which can produce suitable blanks at a high production rate and uniformity which allows these blanks to be used in a machine which automatically tacks these to the finished garments.

The foregoing has been achieved by a specially designed fabric die which hot crimps in a controlled fashion a string of individual belt loops. Moreover, this device produces uniform and quality-wise consistent belt loop blanks joined in a string from which individual blanks can either be severed in a production cycle as each blank is being formed and removed from the heated die, or a continuous string be formed.

Still further, the present invention is directed to a belt loop die crimping assembly operated in a coacting cycle with a belt loop cutting means and belt loop feeding device which not only feeds the belt loop die crimper but also activates a cutting knife severing the formed belt loop blank from the belt loop starting string.

Additionally, novel control means have been incorporated in the novel device which allows for the proper sequential operation of the belt loop die crimper as well as the feed means thereof and providing safety means for operating the die as well as the cutting means.

In order to attain true fusing characterized by a belt loop blank the ends of which cannot ravel, thermoplastic material must be present in the ribbon. There are two sources of this material:

One, most modern fabrics contain a substantial percentage of synthetic (thermoplastic) fibers. These fabrics fuse in the die, which is heated to the softening point of the fibers, without addition of thermoplastic material.

Two, in order to fuse fabrics containing a low or zero count of synthetic material, thermoplastic material must be added. This is easily done by enclosing a strip of thermoplastic film inside the belt loop tube or ribbon.

The crimping treatment may be applied to non-thermoplastic materials such as pure wool or cotton, and a rounded end is obtained. However, the shape is not permanent, and the end will ravel.

With the foregoing in mind and making reference to the figures herein in which the invention has been described, and in which figures like items or items performing substantially similar functions having been identified with the same numerals and wherein:

FIG. 1 shows a tube from which belt loops are prepared;

FIG. 2 shows a crimped string of belt loop blanks;

FIG. 3 shows a separated belt loop blank;

FIG. 4 shows a front view of a belt loop crimper press and die.

FIG. 5 shows a side view of the die and press, partially broken out, and the feed section therefor;

FIG. 6 shows isometrically the bottom view of the top die member, i.e., the downwardly acting die member;

FIG. 7 shows isometrically the bottom and crimping die member assembly with the heating element ports;

FIG. 8 shows an exploded view of the feed toggle clamp and its actuating pneumatic cylinder;

FIG. 9 shows an exploded view of the backfeed preventer lip and linkage assembly associated therewith;

FIG. 10 shows the cutter as well as the feed toggle clamp in an isometric view;

FIG. 11 shows schematically the toggle clamp in feed and return positions;

FIG. 12 shows the pneumatic sensing and actuating circuits associated with the press and feed device interlinked to control the operations thereof; and

FIG. 13 shows the electrical control means employed with the present device.

In reference to the foregoing and making specific reference to FIG. 1, in which the belt loop blank tube 2 is depicted as a continuous ribbon sewed together at seam 3, this ribbon is crimped at sections 4 to form a belt loop blank 6. In the crosshatched area the thermoplastic material is fused to prevent raveling. The crimped sections have conforming fiber lines because of the fusing of the thermoplastic material or an insert in tube 2 (not shown) assumes a desired notch having lines following the notch pattern as shown by item 5 in this figure.

In reference to FIG. 4 which shows the front view of the crimper device and more particularly the die and press section, it consists of a housing having upright members 11 which are on the top part thereof joined by cross-memeber 12 having support for the

pneumatic cylinders

14 and 15 as well as a base member 13 which is bolted to a suitable work support such as a table (not shown). The main pneumatic cylinder 14 which is mounted on the cross-member 12 is a double acting cylinder. Piston rod 17 in turn is joined to a connecting lOl027 member 19 which bears on the top of linear cam 20. Conveniently. the connection 19 may have a space which may be filled with an elastomeric material (not shown) to allow slight lateral and angular freedom for cam 20 to prevent binding of cam 20 and reduce side load on rod 17. The top die press or ram plate 21 and linear cam 20 extend through the side members 11 in slots 23 which slots allow guiding and confining of cam 20 as well as the top die press or ram plate 21.

In order to aid the confinement of cam member 20 and the ram plate 21, ram plate guide support and cam plate guide blocks 47 as well as rollers 441' are also provided on the underside of the ram plate 21. Ram plate 21 extends substantially to the full width of the housing as seen in FIG. 4 and it has a top die guide plate 26 provided for top die ram shaft 22 which moves up and down with the actual press stroke and constrains the compression of the die ram shaft spring 24 during the power cycle.

In actual operation of the die when the downward force of the main cylinder 14 is exerted on the ram plate 21, the belt loop blank 6 is lightly engaged for the full width with the die member 29. The spring 24 is not compressed although it exerts a light pressure on the top die guide plate 26. The plate 26 secures the top die support block 27 having a heated section which not only maintains the relative position of die member 29 but also has an opening (or a plurality of openings) for electrical heating elements (not shown) as well as a sensing device for controlling the temperature of the heated upper die member 29. This die member 29 is shown in FIG. 6 in more detail. As the cylinder 14 continues to exert its force, die member 29 and block 27 are constrained from further downward movement by down die stroke limit bar 39 engaging die member 29 in the cut-out portion shown in FIG. 6. Continued downward motion of cam 20 and ram plate 21 compress spring 24, holding die closed with full force exerted by spring 24.

This causes the lower end of the cam follower arm carrying pin 33 to move the movable crimping die members 34 inwardly in a sliding relationship with the lower heated die member 36 which in turn is supported on a heated section 37, having therein an opening 51 for an electrical heating element (not shown). The lower limit of the press stroke is established when cam 20 is stopped by pivot shaft housing 35. If desired, the

heated sections

27 and 37 may carry an insulating layer such as 49.

After a predetermined time, which allows for crimping and fusing of the fabric in the manner as described above, the power up-stroke of cylinder 14 causes the crimping die members 34 to return to their initial position as well as release the upper die member 29. By appropriately activated pneumatic and electrical control means which will be further explained herein, the feed device 70 is caused to extract the crimped belt loop blank 6 from the die and advance this blank for a predetermined distance to crimp the other end thereof.

In operating the die at a high rate of speed and in order to prevent an undue wear on the die as well as the cam surfaces, it has been found convenient to reduce the main die cylinder 14 stroke by providing two buffer or constraining pneumatic cylinders which extend for a predetermined distance rods 16 which engage the upper surface of cam and reduce the up-stroking distance of main cylinder 14, i.e., rod 17, to a predetermined and desirable degree. A press-up pneumatic back pressure port 40 (having a sensing port closing means 41) is provided on the cam 20 to time the actual stroking cycle via sensor 218 (shown in FIG. 12). In the event an undue time elapses which may cause the belt loop blank 6 to reside in the die section for an undesirable time, an appropriate electrical control device, as further disclosed and described herein, deactivates the pneumatic cylinders 15 and which normally overcome the upstroke force of main cylinder 14. The deactivation of cylinders 15 allows the return of the cam 20 to its up-stroke position and allows the top die members and cam 20 to return to their respective extreme up positions. The down stroke of the press and cam 20 is sensed by a back pressure detector (not shown) in FIG. 4, shown in FIG. 12 as 212, which is connected to a sensing port 44 and causes an appropriate signal to be transmitted to the electrical control devices as well as the pneumatic control devices, when the opening port 44 is covered by an elastomeric material 42 mounted on the cam 20 as shown on the right-hand side of cam 20 in FIG. 4.

In order to facilitate the guiding of the cam 20, appropriate guide bearings 441' may be provided on both sides of cam 20.

As previously mentioned, a layer of insulation such as an asbestos layer 49 may be provided between the two, heated blocks, i.e., upper block 27 and lower block 37 to insulate the same from the upper die plate 26 and base 13, respectively.

With reference to FIG. 6, the upper die 20 is shown with the upper die lands being defined as illustrated in this figure. Further, in reference to FIG. 7, the depicted drawing represents the die members used in the crimping and pressing operation of the belt loop blank. The lower die member 36 via die block 37 is heated, the latter is provided with openings 51 in which are inserted electric resistance heating elements of the cartridge type and a temperature sensor such as a thermistor to sense the proper temperature of the die member. The same heating and sensing arrangement is also employed in upper die member block 27. The base member 13 is secured to the housing member 11 by bolts 13a inserted in tap holes 13b. In turn, block 37 is secured to base member 13 by bolts 37a.

The crimper die members 34 shown in FIG. 7 travel on the lower die member 36 and are confined by the down die stroke limit bar 39 which has a space provided therein for the crimper die member 34 to travel inwardly and outwardly. Bars 39 keep the proper gap between the upper and lower die members. A crimp point in this die member has been. represented by 52. These crimp points 52 do not meet but provide a small continuous section in the string of belt blanks for subsequent cutting or for forming a continuous string of loop blanks 6. Further, the crimp die members 34 are provided with side guides 54 which form a U-shaped section surrounding lower die members 36. Hole 33a is provided for inserting the cam follower arm pin 33 therein.

Turning now to the feed section 70 shown in FIGS. 5, 10 and 11, it consists of an upright housing member 71 for the cutting knife 76 and a split toggle clamp 94 which acts as an extractor of the belt loop blank, i.e., as a movable clamping device. Housing member 71 has a horizontal member 72 fixedly attached thereto and carrying on top thereof the pneumatic spring-return cylinder 74 and its rod 74a at the end of which is a cutting knife 76. Cutting knife 76 has a notch 7611 which allows the knife to cut the string when toggle clamp 94 is in its forward, returned position. To the upright housing member 71 is also affixed perpendicularly thereto structural member 77 which supports the cutting anvil 79 as well as the feed section base plate 90 for the feed cylinder 92a. The cutting anvil 79 is a cantilever member rigidly fastened to cantilever cutting anvil support post 87 which in turn is affixed to the member 77 supporting the anvil 79 and the feed section base plate 90. The cantilever cutting anvil 79 support post 87 also carries at the forward edge thereof and spaced apart two feed gate posts 80 between which a backfeed preventer latch or lip 81 is positioned. The function of this backfeed preventer latch 81 will be further explained herein.

As FIG. 10 does not show the operation of latch 81, reference should be made to FIG. 9 which shows the backfeed preventer latch and linkage assembly therefor in an exploded view in which the backfeed preventer lip support bar 82 is inserted into bar linkage 83 which is held in a latch engaging position by spring 84 attached to spring post 86. Spring post 86 is attached to member 71. Consequently, the backfeed latch preventer lip 81 is engaged at all times and exerts a positive downward pressure on the belt loop while the same is die crimped.

In feeding the crimping die, the belt loop blank is advanced to the next, indexed crimping position as it is extracted from the heated die by the double acting, two position split toggle clamp 94 shown in FIG. 8 in exploded view. FIG. 11 shoes a feed position when the clamp 94 is in the left-most part of stroke, assumes the orientation designated as B, and is ready to pull away from the die. When clamp 94 is stroking forwardly, i.e., towards the die, it assumes an idle position A shown by dotted lines in F IO, 11. Toggle clamp 94 is activated by the pneumatic double acting cylinder 9211, which cylinder is supported by a toggle cylinder support base 91 in an articulated position on post 91a. The toggle rolls on a bar member 93, which bar member 93 pivots on a rubber block 93a and shoulder screw 93b secured in block 930 which in turn is affixed to support base 91. The double acting toggle clamp 94 is placed in its ready-to-return position by the toggle clamp return position switching block 95 located underneath the cantilever anvil 79 when the toggle rollers 111 strike the elastomeric pad 95a at the completion of the feeding stroke. Block 95 is affixed to the bar member 93. On its forward stroke, the toggle clamp 94 is switched to its feed position, i.e., to assume the other stable position as shown in FIG. by hitting the elastomeric pad 88a on the surface of the cutting anvil support post 87 which acts as a toggle switching device. As the spring 92 is being constantly urged upwardly thereby urging bar member 93 upwardly, it always exerts a positive pressure against the outer surface of rollers 111 shown in FIG. 8.

In order to understand more completely the operation of the toggle clamp 94, reference is now made to FIG. 8 in which an exploded view of the toggle clamp 94 is shown by illustrating one side of it. The other side of the toggle clamp 94 is identical. As mentioned before, the feed cylinder 92a is a pneumatically operated double acting cylinder. Feed cylinder 92a has a rod 101 on which is mounted a feed cylinder rod back pressure sensor collar 102 and a stroke length adjustment collar 104 for the feed cylinder rod 101. Collar 104 in cooperation with adjustable block 95 determines the length of belt loop blank, i.e., when the other end of the blank is positioned for crimping. In the event the length of belt loop is desired to be changed, the feed stroke may be lengthened or shortened by moving block 95 and substituting a collar of different length. The toggle clamp arm 110 is mounted on a toggle clamp arm support and slide guide 106 which has a U shaped section in which the cantilever anvil plate 79 resides. A main pivot shaft 107 is for the toggle clamp arm 110 to shift from one stable position to another. Shaft 107 is received in the main shaft hole 108. At the end of this shaft and interiorly to the toggle clamp arm 110 is a roller 109 such as a needle bearing. A lower roller 111 is mounted on the lower shaft 113 of the toggle clamp arm 110. This roller rotates on shaft 113 which shaft in turn is secured by a shaft nut 112. The main shaft 107 in turn is secured to arm 110 by a main shaft retaining ring 114. In operating the toggle clamp 94 on the forward stroke of cylinder 92, the toggle clamp 94 is being urged forwardly with the toggle arms 110 switched rearwardly and restrained by surface 110a shown in FIG. 8. In this position, the rollers 111 ride on the spring support bar 93. As the leading edge of the toggle clamp rollers 111 strikes the edge of.

elastomeric block 88a attached to support post 87, the toggle clamp 94 assumes its other stable position because the inertial force causes the toggle clamp 94 to go from one stable position to the other stable position due to the relationship of the shafts 107 to 113. The arms 110 on both sides of the toggle clamp move forwardly and engage a belt loop blank which blank is restrained from going backwardly by back feed restraining lip 81. The feed position oftoggle clamp 94 is illustrated in FIG. 10 shortly before the switching of clamp 94 for its return stroke or idle stroke.

After the knife 76, striking behind arm 110, has cut the loop while the forward end of the loop is under the hold down blade 96, and after an air jet from jet nozzle 99 has blown this cut loop blank into suitable receptacle, the pneumatic cylinder 92a is activated and the toggle clamp 94 pulls a new loop blank into a position for die crimping and fusing.

The feeding or pulling of the belt loop blank is accomplished by the edges of arms 110 engaging the loop and pulling it under the hold down blade 96. The clamping force is derived from the force of spring 92 as it urges arms 110 on to the loop through the lever action of the arms 110. As the toggle clamp 94 moves backwardly in the position as shown in FIG. 10, the return position switching block 95, when struck by the leading edge of roller 111, causes the toggle clamp 94 to switch and disengage the upper part of arms 110 from the belt loop blank. The return position switching block may be provided at its upturned L-shaped end with an elastomeric cover 95a.

As mentioned before, when the cylinder 74 returns to the right most position, i.e., towards the non-extended position of rod 101 the toggle clamp 94 overcomes the pressure of the spring 92 with the aid of the freely rotating bearings 111 as the cylinder rod 101 moves it to its switching position against the up-turned lip of switching block 95 or the elastomeric shock absorber 95a as the case may be. When this happens, the collar 104 together with the rod sensor collar 102 has come to rest against the extreme left-hand end of cylinder 92a and the toggle support block 106. In this position, the toggle switch 94 is ready for its return or forward stroke with rollers lll leading, which, when striking the block 87 is switched into a feed position.

The operation and timing of the machine will now be explained by reference to FIGS. 12 and 13 and the pneumatic and electrical control circuit which will further amplify the above description. When the master switch of the machine is turned on, the proper temperature has been achieved in the bottom die and top die blocks 37 and 27, respectively, and when the start button is pressed, a timer means is turned on. This means extends cylinders 15 for the predetermined length. This means also initiates the press cycle since port 40 is covered by closure means 41 and re-starts the timer. Simultaneously, a valve on the return line of the double acting cylinder 14 goes off, i.e., it is shut off electrically as explained in the reference to the electric control means. Thereafter, solenoid valve 14d is turned on, the cylinder 14 is operated on its down stroke by admitting the pneumatic fluid under pressure on the down stroking or power stroking side of the double acting cylinder 14.

The double acting toggle clamp 94 has been moved to that forwardmost position, i.e., in a feed position and has closed the feed forward" sensor port 88 by pressing against a resilient spring-like cover 88a thereby closing port 88 which causes to admit pneumatic fluid to the downstroking cylinder 74, provided, however, a safety cover 116a (not shown) for the knife section is closed as determined by cover sensor port 116 and further, provided that the feed cylinder 92a is in its forwardmost position and the lower bearings of toggle 111 block the opening of port 88, i.e., when the toggle arrives at switching block 87 and covers port 88.

The basic cycle period of the machine is established by flow control valve E in FIG. 12. This valve controls the downward speed of cylinder 14. Since cylinder 14 will return as soon as port 44 is closed, valve E determines the length of time the loop is in the die.

The timer means holds cylinders 15 extended during normal operation. The period of the timer is substantially longer than the operating period set by valve E. As long as the machine cycles normally, timer stays on, since it is restarted each cycle.

In the event machine fails to cycle for any reason, the timer will run out since it has been restarted. Cylinders 15 will retract, and the die will open completely preventing scorching of the loop and facilitating reloading of the machine.

In reference to FIG. 12, closing

ports

116 and 88 cause back pressure to build up in actuator D, opening valve C, causing cylinder 74 to actuate.

When these conditions are satisfied, the knife goes down. Next, the press cylinder 14 at this point has also bottomed and it has closed the press back pressure sensor port 44 by means of the elastomeric cover 42.

The knife 76 is returned after the cutting stroke to its uppermost position, i.e., the source ofback pressure for the actuator D is the air to the press cylinder 14, the knife returns simultaneously with the press.

The proper sequence at this point is:

a. Port 44 covered (press all the way down);

b. This causes 14a! to turn off, Me to turn on;

c. In turn this causes press to go up (because 142 is on and 14d has exhausted). Knife 76 goes up (spring return);

d. Port 40 is covered by 41, which ensures die is open for free feeding ofloop;

e. Valve 216 (feed) opens; feeder cylinder 92a completes stroke and toggle clamp 94 switches;

f. When port 102a is covered, cycle repeats.

If a continuous string of belt loop blanks is being formed, the knife 76 is disconnected by shutting off the pneumatic fluid to cylinder 74. When valve 14d is shut off, a quick exhaust port 74c which is provided for cylinder 74 allows rapid operation of cylinder 74. Thus quick exhaust port facilitates the shortening of the operating cycle. In a companion application entitled Detecting Means for Single or Multiple Plies" (CMS 263605, Serial No. 44,772, filed June 9, 1970) the principle of the back pressure sensing means is explained.

The following will be the description of the electrical circuit means. This circuit means are provided to control the operation in conjunction with the pneumatic means immediately described above. The electrical control circuit shown in FIG. 13 performs the functions of raising and lowering the die cylinders, actuating the feed mechanism at the appropriate time in the cycle of the machine, and automatically stopping or preventing the starting of the machine if it is jammed or if the temperature of the dies is incorrect. Furthermore, it controls the temperature of the dies.

The control circuit 200 shown in FIG. 13 has six relays, I(,, K K K,,, K and K,. The contacts for each relay are shown directly below the coil for that relay, in the conventional manner. Each contact arm is shown in its upper position, in which it will be located when its coil is not energized. When the coil is energized, each contact arm moves downwardly to its lower contact.

As will be explained in greater detail below, a temperature monitor circuit 240 is provided for each of the two die members, i.e., 29 and 36. Whenever the temperature of the die members is correct, relays K and K, will be energized and the contacts associated with those relays will be closed downwardly, in accordance with the explanation to be given below.

The system is started by momentarily closing the starting switch 8' (ref. no. 222) which is mechanically coupled to a second start switch A" (ref. no. 214). The closing of starting switch 222 momentarily grounds one terminal of the coil of relay K, through closed relays K and K,. The other terminal of the coil of K, is connected to a+26 volt DC source at terminal 231, and thus is energized by the closing of switch 222. The energization of relay K, connects its contacts 6-7 together and thus connects one terminal of the coil of relay K to a 120 volt AC supply 202. The closing of start switch 214 connects the other terminal of the coil of relay K to ground, thus energizing relay K Relay K then is latched in its energized condition by the closing of its contacts 1-3.

The actuation of relay K energizes the coil 208 of the pressdown valve 14a to start the cylinder 14 moving downwardly from it uppermost position. One terminal of coil 208 is connected to ground through contacts 6-7 of relay K whereas the other terminal of coil 208 is connected to the alternating current source 202.

When the cylinder has reached the bottom if its stroke, the press-down microswitch 212 is actuated via sensor port 44, opening the line which energizes coil K and deenergizing the relay K This causes the coil 206 of the press-up valve 14c to be energized through the contacts -6 of relay K and starts the cylinder back upwardly towards its uppermost position.

When the cylinder reaches the top of its stroke, the press-up microswitch 218 via back pressure sensor port 40 is actuated so as to energize the feed valve coil 216 through the contact arm of the start switch 214 and the press-down switch 212. This starts the feed cylinder 92a in motion, and the feed cylinder pulls another length of belt loop material through the press and die assembly. At the end of the feed cylinder stroke, the feed microswitch 210 is actuated via sensor 102a, causing K to be energized and latched again so as to re-start the operation cycle automatically. Of course, for this automatic operation, the automatic-manual selector switch 204 must be in its automatic position as is shown in FIG. 13.

In accordance with another aspect of the present invention, a timing circuit 238 is provided to stop the operation of the machine if it is cycling at too slow a rate. For example, if the machine becomes jammed or stops cycling for any reason, the circuit 238 operates to deenergize the machine and place it in a stand-by condition. The operation of this circuit is as follows:

When the start switch 222 is momentarily depressed, relay K, is energized, and +26 volts DC is applied through contacts 11-9 of relay K, to provide base drive current for a transistor 224 whole emitter-collector path is connected between one terminal of the coil of relay K, and ground. Thus, when the start switch 222 is released, the transistor 224 will provide a low impedance path to ground for the coil of relay K,, thus maintaining it in an energizing condition.

When the relay K was deenergized, a capacitor 230 was connected to the +26 volt DC terminal 231 and the capacitor 230 was charged to that voltage. The energization of relay K connects

contacts

11 and 9 of that relay together. This connects the capacitor 230 across the base bias circuit 231 of a transistor 228. The application of the voltage on capacitor 230 to the transistor 228 turns that transistor on, thus providing a short-circuit path to ground around another capacitor 232 and discharging that capacitor.

After capacitor 230 discharges completely, the transistor 228 turns off again, and the capacitor 232 starts charging again through contacts 1l-9 of relay K, and a series charging circuit 233.

Depending upon how long it takes for relay K to be deenergized again, the capacitor 232 either will charge for a certain length of time and then be discharged by the turning on of transistor 228 again, or it will charge up to a voltage which exceeds the 12 volt Zener breakdown voltage of Zener diode 234. In the latter case, the breakdown of diode 234 will turn on a transistor 226 whose emitter-collector path is connected between ground and the base lead of transistor 224. Thus, the actuation of transistor 226 turns off the transistor 224, and deenergizes the relay K,. This open contacts 6-7 of relay K, and thus deenergizes the auxiliary cylinder valve 220 (in the upper left hand corner of FIG. 13) and causes the cylinder to be raised so that the dies will not contact the belt loop material and scorch it. Of course, the feeding and other portions of the machine are stopped.

The time constants of the discharge paths for

capacitors

230 and 232 are relatively low so that those capacitors discharge relatively rapidly. However, the time constant for the circuit for charging capacitor 232 is relatively higher and can be controlled by setting the potentiometer 235 connected in series with the capacitor 232. The time constant of the charging circuit for capacitor 232 is set at a value such that the voltage across capacitor 232 will not reach 12 volts during a normal operating cycle of the system. Thus, the turning on and the turning off of relay K in a normal cycle of operation is used to control the charge and discharge of the capacitor 232 and controls the automatic stopping and die-lifting circuitry to prevent scorching of material which might be jammed in the machine.

Also shown in FIG. 13 are a pair of heating elements 270 which are used to heat the

die members

29 and 36. The flow of electrical energy through each heating element 270 is controlled by means of a relay K or K whose operation is controlled by a heating control circuit 242. Only one of the circuits 242 is shown in FIG. 13, for the sake of simplicity in the drawings.

Two monitoring circuits 240 also are provided. One monitoring circuit controls the operation of the relay K and the other circuit 240 controls the operation of relay K If the die temperature of either die is substantially different from what it ought to be, such as it will be during start-up after the dies have cooled, the monitor circuits will prevent the energization of relay K; or K and will prevent the starting of the system. When the dies have heated up to the proper temperature, the system then can be started.

Now considering the operation of the temperature controller circuit 242 in "greater detail, 120 volt alternating cur rent is applied to a step-down transformer 244 which has a center-tapped secondary winding which is formed into two

halves

246 and 248, with the center tap being grounded. Each of the winding

halves

246 and 248 forms one arm of a bridge circuit which is indicated at 249. Connected to the opposite ends of the secondary winding are the other two arms of the bridge circuit, one including a thermistor 252 which senses the temperature of the die, and the other arm including a temperature-setting potentiometer 250. The output signal from the bridge circuit 249 is conducted through a coupling network 254 to two cascaded amplifier stages 258 which amplify the bridge output and deliver it to the gate lead 264 of a SCR device 268. Referring to the left-hand portion of circuit 242, the relay K is energized by means of the SCR device 268 which receives 120 volt alternating current from the supply 202 through a direct connection 266 of its anode to the supply 202. As mentioned above, the gate lead 264 of the SCR 268 receives the amplified output signal from the bridge circuit 249. Whenever the resistance of the thermistor 252 is higher than that of the temperature-setting potentiometer 250, thus indicating that the temperature of the die is too low, the voltage is supplied to the anode 264 of the SCR that is developed by the in-phase half of the secondary winding of transformer 244, with the result that the anode voltage and gate voltage of the SCR 268 are in phase with one another. Thus, the SCR conducts power, turns on the relay K and the heating element 270 is heated until the temperature of the die is high enough to give the thermistor 252 a resistance lower than that of the potentiometer 250. When this happens, the voltage supplied to the gate 264 of the SCR 268 becomes 180 out of phase with the voltage supplied to the anode of the SCR, with the result that the SCR does not conduct any current, the relay K,, is turned off, and the heating element 270 is no longer energized. In this manner, the temperature of each die is controlled within desired limits.

Now considering the temperature monitor circuits 240, whenever the temperature of the die is approximately correct, there will be little or no output voltage from the bridge circuit 249. This fact is used to advantage in the monitor circuit 240.

The bridge circuit output signal is conducted through a coupling network 272 to an amplifier 274. The amplified signal flows through a diode 276 which rectifies the AC current it receives and charges up a capacitor 282. The capacitor voltage is applied to an emitter-follower circuit 284 whose output is delivered to a Schmitt trigger circuit which includes

transistors

286 and 288, and bias diodes 278, The coil of the relay K is connected between a+26 volt DC source and the collector of transistor 288.

Because of the low level of the output from the bridge circuit 249, there will be little output current from the amplifier 274, with the result that there will be little DC charge stored on the capacitor 282. Thus, there will be little drive current for emitter-follower 284, with the result that transistor 286 will be off and transistor 288 will be on, relay K will be turned on, and the machine can be started (assuming K, has been energized similarly).

However, if the bridge voltage is substantially different from what it ought to be, as it will be upon starting the machine after the dies have cooled, a relatively large voltage will appear across the capacitor 282, thus turning transistor 286 on and transistor 288 off, thus deenergizing relay K and prevenbv ing the starting of the system.

Thus, circuitry has been provided for automatically controlling the temperature of the dies and preventing premature starting of the system.

From the above, it is evident that means have been provided for forming belt loop blanks in a die and die crimping device from which device the formed belt loop blank is extracted and cut, if desired, in a feed and cutting device in the described manner. Further, means have been described which control the operation of the die device and the feed device thus ensuring an automatic trouble-free operation.

What is claimed is:

1. In a machine for hot crimping a string or tube from which belt loop blanks are formed, the combination comprising:

a first heated die member including means for a reciprocating press means and a guide means therefor;

a second heated die member;

a pair of crimping die members, each to the other oppositely reciprocating and operatively engaged with said second die member;

means for urging oppositely and inwardly said crimping die members operatively interconnected to said means for reciprocating said first die member;

means for retracting said first die member including means for limiting retraction thereof;

means for withdrawing said crimping die members from each other operatively interconnected to the means for retracting said first die member; means for feeding said string into a crimping position, said means for feeding being operatively interconnected with said means for retracting said first die member; and

means for severing a crimped belt loop blank said means for severing being operatively interconnectable with means for feeding said string.

2. Tile machine for hot crimping a tube from which belt loop blanks are made as defined in claim 1 and wherein the means for feeding comprises: a two-position toggle clamp; a first switching block for feedingly engaging said toggle clamp to a belt loop blank; a second switching block for releasing said belt loop blank from said toggle clamp and placing said toggle clamp for return to a feed position; means for reciprocating said toggle clamp between said first and second switching blocks; a spring means for keeping said toggle clamp in a stable position; means for travel for said toggle clamp for reciprocating between said first and second switching blocks; means for sensing said toggle clamp in respect to a feed position and a belt loop blank release position; and, means for severing said belt loop blank operatively interconnectable with said toggle clamp.

3. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 2 and wherein means for travel for said toggle clamp is also an'anvil means for a blade severing an individual belt loop blank from said tube.

4. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 2 and wherein the means for sensing said toggle clamp in respect to said feed position is a back pressure sensor operatively interconnected with said first switching block.

5. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 2 and wherein the means for sensing said toggle clamp in respect to the belt loop blank release position is a back pressure sensor operatively interconnected with said means for reciprocating said toggle clamp.

6. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 2 and wherein the means for sensing said toggle clamp in respect to the belt loop blank release position is a back pressure sensor operatively interconnected to a stop means on a means for driving said toggle clamp as reciprocating means therefor and wherein said stop means on said means for driving said toggle clamp is also the means determining the length of a belt loop in respect to a feed cycle to said dies.

7. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 2 and wherein means for retaining a belt loop blank is provided above said means for travel for said toggle clamp.

8. The machine as defined in claim 7 and wherein a means for retaining said belt loop blank is operatively interconnected with means for ejecting said belt loop blank and interconnected with means for reciprocating said toggle clamp.

9. The machine for hot crimping atube from which belt loop blanks are made as defined in claim 2 and wherein the means for severing said belt loop blank is a driven knife operatively interconnected to sever a belt loop blank when said toggle clamp is in a ready-to-feed position.

10. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 2 and wherein the means for severing said belt loop blanks is provided with means for rendering inoperative said means for severing whereby a continuous string of crimped belt loops is obtained.

11. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 2 and wherein the means for feeding said belt loop blank includes means for preventing backfeed of said belt loop blank.

12. The machine for hot Crimping a tube from which belt loop blanks are made as defined in claim 1 and wherein each of said first die members and said second die members includes means for heating, means for sensing and means for controlling a temperature of said first and second die members.

13. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 1 and wherein means for retracting said first die member includes means for limiting said means for retracting said first die member whereby a crimping cycle of said machine is shortened.

14. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 13 and wherein said means for limiting said means for retracting said first die are operatively interconnected with said means for monitoring the operation of said machine whereby the means for limiting are rendered inoperative upon improper cycling ofsaid machine.

15. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 1 and wherein said first die member comprises a die block attached to said first die member, an insulation for said die block; a die plate attached to said die block, with said insulation therebetween, said die plate engaging means for guiding said die plate; a die rod fixedly engaged to said die plate; a spring surrounding said terconnected with said cam means and with said crimping die members; means for urging said first die member downwardly, operatively interconnected to said first die member, said cam means, and said crimping die members; means for sensing said means for urging by holding said first die downwardly at a completion of downward urging; and means for sensing said means for retracting upwardly said first die operatively interconnected to said means for sensing said means for urging said first die downwardly and means for automatically cycling said machine.

16. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 1 and wherein the pair of crimping die members comprise: a formed die point to define a crimp configuration; a channel means in each of said crimping die members operatively ingaging said heated second die member; a uide ap erature means on top of said second die member %or said crimping die members to guidingly reciprocate; an apperature in each of said crimping die members for engaging a cam follower arm; a cam follower arm pivotingly engaged with said guide means for said first die; a cam means attached to said means for urging said first die, engaged with said cam follower whereby said crimping die members are urged inwardly; and a cam means attached to said means for retracting said first die, engaged with said cam follower whereby said crimping die members are urged outwardly.

17. The machine for hot crimping a fabric tube from which belt loop blanks are made as defined in claim 2, and wherein the two position toggle clamp comprises: a pair of feed arms facing each other, a major shaft for each of said arms; a guide block carrying said major shaft near one end thereof, said major shaft carrying each of said bearings between said arm and said block; a second bearing on a switch shaft attached to each of said arms, said switch shaft, in respect to said major shaft, pivotingly oscillating between a first stable position and a second stable position, whereby said first stable position is a feed position, and a second stable position is a return position; said bearings on said switch shaft engaging abuttingly downwardly a first travel means for said toggle clamp, said bearings on said major shaft engaging a second travel means abuttingly upwardly; said guide block engaging upwardly said second travel means; a spring means urging said first travel means upwardly; a pair of switch means each for switching said toggle from one stable position to another; and a reciprocating means engaged to said guide block reciprocating said guide block between said switch means whereby said switch bearing, upon striking said switch means is urged downwardly as restrained by said bearing on said major shaft engaging the second travel means and whereby the toggle clamp assumes a stable position.

18. The machine for hot crimping a string from which a belt loop blank is made as defined in claim 1 and including means for automatically cycling said machine.

19. The machine for hot crimping a string from which a belt loop blank is made and as defined in claim 18 and wherein the means for automatically cycling said machine includes means for monitoring the proper operation of said machine.

323 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 2 61113 1 ALL Dated Maw-0h 11L] W079 I Inven fl Louis William Brecht Jr.

It is certified that error appears in the above-identified patent and that said Letters Patent ,are hereby corrected as shown below:

In theHeadingz' 7 After "Court, El Paso, Tex. 79915" insert I -Assignee: Farah Manufacturing Company, Inc.

El Paso, Texas Signed and sealed this 7th day of November 1972.

(SEAL) Attest:

EDWARD M.FLETCHER, JR. ROBERT GO'I'TSCHALK Commissioner of Patents Attesting Officer

Claims

1. In a machine for hot crimping a string or tube from which belt loop blanks are formed, the combination comprising: a first heated die member including means for a reciprocating press means and a guide means therefor; a second heated die member; a pair of crimping die members, each to the other oppositely reciprocating and operatively engaged with said second die member; means for urging oppositely and inwardly said crimping die members operatively interconnected to said means for reciprocating said first die member; means for retracting said first die member including means for limiting retraction thereof; means for withdrawing said crimping die members from each other operatively interconnected to the means for retracting said first die member; means for feeding said string into a crimping position, said means for feeding being operatively interconnected with said means for retracting said first die member; and means for severing a crimped belt loop blank said means for severing being operatively interconnectable with means for feeding said string.

2. THe machine for hot crimping a tube from which belt loop blanks are made as defined in claim 1 and wherein the means for feeding comprises: a two-position toggle clamp; a first switching block for feedingly engaging said toggle clamp to a belt loop blank; a second switching block for releasing said belt loop blank from said toggle clamp and placing said toggle clamp for return to a feed position; means for reciprocating said toggle clamp between said first and second switching blocks; a spring means for keeping said toggle clamp in a stable position; means for travel for said toggle clamp for reciprocating between said first and second switching blocks; means for sensing said toggle clamp in respect to a feed position and a belt loop blank release position; and, means for severing said belt loop blank operatively interconnectable with said toggle clamp.

3. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 2 and wherein means for travel for said toggle clamp is also an anvil means for a blade severing an individual belt loop blank from said tube.

9. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 2 and wherein the means for severing said belt loop blank is a driven knife operatively interconnected to sever a belt loop blank when said toggle clamp is in a ready-to-feed position.

14. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 13 and wherein said means for limiting said means for retracting said first die are operatively interconnected with said means for monitoring the operation of said machine whereby the means for limiting are rendered inoperative upon improper cycling of said machine.

15. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 1 and wherein said first die member comprises a die block attached to said first die member, an insulation for said die block; a die plate attached to said die block, with said insulation therebetween, said die plate engaging means for guiding said die plate; a die rod fixedly engaged to said die plate; a spring surrounding said die rod, said spring abutting a ram plate and said die plate; said die rod horizontally guidingly restrained by said ram plate and vertically downwardly unrestrained by said ram plate in an apperature in said ram plate; a means for vertically guiding said ram plate in common with said means for guiding said die plate; a horizontal restraining means for said ram plate; a cam means having a plurality of cam lands; said cam means guidingly horizontally and guidingly vertically interconnected with saiD ram plate; a plurality of cam followers operatively interconnected with said cam means and with said crimping die members; means for urging said first die member downwardly, operatively interconnected to said first die member, said cam means, and said crimping die members; means for sensing said means for urging by holding said first die downwardly at a completion of downward urging; and means for sensing said means for retracting upwardly said first die operatively interconnected to said means for sensing said means for urging said first die downwardly and means for automatically cycling said machine.

16. The machine for hot crimping a tube from which belt loop blanks are made as defined in claim 1 and wherein the pair of crimping die members comprise: a formed die point to define a crimp configuration; a channel means in each of said crimping die members operatively ingaging said heated second die member; a guide apperature means on top of said second die member for said crimping die members to guidingly reciprocate; an apperature in each of said crimping die members for engaging a cam follower arm; a cam follower arm pivotingly engaged with said guide means for said first die; a cam means attached to said means for urging said first die, engaged with said cam follower whereby said crimping die members are urged inwardly; and a cam means attached to said means for retracting said first die, engaged with said cam follower whereby said crimping die members are urged outwardly.