US3744785A

US3744785A - Shop towel folder

Info

Publication number: US3744785A
Application number: US00150553A
Authority: US
Inventors: C Grantham
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-06-07
Filing date: 1971-06-07
Publication date: 1973-07-10
Anticipated expiration: 1990-07-10

Abstract

A shop towel folder having an inlet conveyor, a normally stationary first knife under the exit end of the inlet conveyor and having a leading edge directed generally upwardly, a second knife above and beyond the exit end of the inlet conveyor, working rearwardly; as the towels lead downwardly off the inlet conveyor, it engages the towels so as to move them over the first knife where they fold in half thereover, and form a stack thereon, and after a predetermined number of towels are so stacked, the first knife is moved forwardly, forming a crease in the stack and forcing the leading edge formed by the crease into a second conveyor, whereby the stack is carried as a unit and a bundle to a depository.

Description

United States Patent [1 1 Grantham 1 July 10, 1973 SHOP TOWEL FOLDER Primary Examiner-Antonio F. Guida [76] Inventor: Charles R. Grantham, 1154 E. 12th j g 'q'fig St., Los Angeles, Calif. 90021 a [22] Filed: June 7, 1971 57 ABSTRACT [21] Appl. No.: 150,553 1 A shop towel folder having an inlet conveyor, a normally stationary first knife under the exit end of the [if] :J.S.il. 270/4a227(l)/33 inlet conveyor and having a leading edge directed f 45 erally upwardly, a second knife above and beyond the 1 l exit end of the inlet conveyor, working rearwardly; as 5 R i d the towels lead downwardly off the inlet conveyor, it 6] e engages the towels so as to move them over the first UNITED STATES PATENTS knife where they fold in half thereover, and form a 1,793,552 2/1931 Kast 270/45 UX stack thereon, and after a predetermined number of 361,376 4/1887 Scott 270/45 towels are so stacked, the first knife is moved for- Stonemetz wardly forming a crease in the tack and forcing the leading edge formed by the crease into a second conveyor, whereby the stack is carried as a unit and a bundle to a depository.

8 Claims, 10

Drawing Figures sum

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1 SHOP TOWEL FOLDER FIELD OF THE INVENTION The device of the invention is for use in folding what are known as shop towels, normally used by people in a shop for wiping dirt and grease from their hands, and from articles. The users of these towels desire them to be folded in a stack or bundle, or bunch, with the towels interfaced throughout their full areas, and the stack then folded, all of them being folded together, as distinguished from folding the towels individually and stacking them after they are folded.

OBJECTS OF THE INVENTION A broad object of the invention is to provide a novel folder for folding shop towels in stacks, i.e., the towels are stacked together in face-to-face relation before being folded, and thereafter a single fold is made in all of the towels of the stack.

Another object is to provide a shop towel folder of the foregoing character, having a novel construction in which the towels are placed in a stack on the edge of a knife, and that knife is then moved toward a second conveyor, and as the knife is so moved, it forms a fold in the stack which as so folded are carried by the second conveyor to the outlet of the machine.

Another object is to provide a shop towel folder of the foregoing character which includes an arrangement facilitating feeding of the towels into the folder, including an inlet conveyor and arranged so that the operator need only place a small portion of the leading end of each towel thereon, and whereby the towels are then conveyed through the folder, and folded.

Still another object is to provide a shop towel folder of the foregoing character which produces even and uniform folding of the towels.

An additional object is to provide a shop towel folder of the foregoing general character incorporating an efficient operation and particularly the operation of conveyance of the towels therethrough, including relatively fast moving conveyors at the entry end for carrying the individual towels to the stacked position, and then carrying the towels from such stacked position, at a slower rate, considering that the conveying means for carrying the individual towels into stacked position must be at a relatively rapid rate in order to carry the towels as fed by the operator, and the stacks need not move so fast since it operates to convey the stacks rather than individual towels, each stack containing for example ten and need not move so fast as the infeeding conveying means.

Still another object of the invention is to provide a shop towel folder of the foregoing general character including novel means for folding the towels including an arrangement for carrying the towels into a stacking position, namely each towel leads linearly from the inlet conveyor to the first knife and the leading edge of each towel goes beyond the edge of the first knife, and a second knife engages the towel at a latter portion and moves it back into a folded and stacked position on the first knife, whereby the stacking of the towels is relatively rapid, and whereby additionally, reliance is not made on the ordinary linear movement of the towels, but the second knife speeds up the folding operation, and the trailing portion of the towel is carried into folded position by the inlet conveyor itself.

A still further object of the invention is to provide a shop towel folder of the character just immediately referred to in which efiiciency and speed of operation is enhanced by a novel arrangement in which the first knife on which the towels are placed for folding, is moved forwardly in folding direction in synchronized relation to the last towel to be included in the stack, whereby it catches that towel in mid-air, and holds that towel by so doing, and moves that towel together with all of the others in a stack, in a folded condition into the exit conveyor, which carries the stack thus folded to the exit end of the folder.

An additional object is to provide a shop towel folder of the foregoing character which is of extremely simple construction, and which is believed to be the first successful shop towel folder so far produced.

Another and very important object is to provide a shop towel folder in which all of the conveying means are continuously operating, i.e., there are no intermittently operating type of conveying means (whether belts, rollers etc.) and thereby it is unnecessary to provide brake means, clutch means, etc., as in other types of machines, resulting in a greatly simplified structure and operation.

DESCRIPTION OF A PREFERRED EMBODIMENT:

In the drawings:

FIG. 1 is a side elevational view of a shop towel folder made according to the present invention;

FIG. 2 is a large scale detail view of the portion of FIG. 1 and indicated by the arrow 2;

FIG. 2a is a detail view taken at line 2a-2a of FIG.

FIG. 3 is a longitudinal vertical sectional view of the principal folding members oriented according to line 3--3 of FIG. 2;

FIG. 4 is a view similar toFIG. 3 with certain members in alternate positions; v

FIG. 5 is a perspective view of a portion of the folder taken substantially in the direction of the arrow 5 of FIG. 1;

FIG. 6 is a perspective view of the second knife utilized in folding the towels;

FIG. 7 is a perspective view of the flippers used in the folder, and associated elements, oriented according to the arrow 7 of FIG. 1;

FIG. 8 is an end view of the flippers and associated conveyor means, oriented according to line 8-8 of FIG. 7; and

FIG. 9 is a diagram of the electrical circuit used in the folder.

Referring in detail to the accompanying drawings, attention is directed first to FIG. 1 showing the shop towel folder as a whole. The folder includes a frame 20 of suitable kind, an inlet conveyor 22 and an exit conveyor 24, both driven by suitable driving means, such as a motor 26, which operating through various drive transmitting members including a belt 28, drives the

conveyors

22, 24.

The inlet conveyor 22 has a lower end adjacent the front end of the machine on which the operator places the shop towels 29, on which they are carried thereby inwardly and upwardly. Preferably the inlet conveyor 22 is made up of a plurality of belt elements 30 having gaps 32 between adjacent belt elements. The belt means may be of a width similar to the width of the shop towels, so that the towels when placed thereon cover the gaps, and in so doing operate an actuating or control means utilized in the folding operation. This control means includes a PE cell 34 of retro-reflective type, operative in conjunction with a reflective plate 36, and upon a beam from the cell passing through one of the gaps 32, and when a towel passes upwardly on the belt means and covers the plate 36, it breaks the beam and causes a folding operation to be described hereinbelow. The arrangement of the PE cell and plate are shown more fully in FIG. 2 where a towel 29 is approaching the plate 36 and when it passes thereover it breaks the beam from the cell.

Associated directly with the inlet conveyor 22 is a first folding knife or blade 38 which may be curved, and is mounted on a pair of arms 40 pivotally mounted by suitable construction in the frame. .The folding blade is movable between a retracted position shown in full lines in FIG. 3 and an advanced position shown in dot-dash lines in that figure, being moved to those positions by suitable means such as an air cylinder 44 under the control of a solenoid valve 45 (FIG. 9). The blade 38 has a leading edge 42 which, when the blade is in retracted position, extends upwardly and rearwardly and when the blade is moved to advanced position, the leading edge, with the towels thereon as described more fully hereinbelow, approaches and enters into the bight 62 of the exit conveyor 24.

The blade 38 is disposed under the exit end of the inlet conveyor 22 and the towels 29 on riding up the inlet conveyor 22 drop off the exit end as indicated at 29a, this towel having a forward portion 29f and a trailing portion 29t, the forward portion dropping down below and beyond the leading edge 42 of the folding knife 38.

Associated with the folding knife 38 and the inlet conveyor 22 is a second folding knife or blade 46, also known as a wigwag, having a knife proper 48 mounted on arms 50 pivotally mounted in the frame at a suitable position. This second folding knife 46 is movable between a retracted position shown in full lines in FIGS. 3 and 4, and an advanced position shown in dotdash lines FIG. 3 and full lines in FIG. 1, and being moved to those positions by suitable means such as an air cylinder 52 (FIG. 2) under the control of a solenoid valve 53 (FIG. 9), which in turn is actuated under the control of the PE cell 34 when the towels move up the inlet conveyor and pass through the beam of that cell. The PE cell is operatively associated with timing means 55 (FIG. 9), the timing of which issuch that the second folding knife 46 is moved to advanced position to catch the towel (FIG. 3) at about its center, or other appropriate location, but in such position as to fold the downcoming towel over the leading edge of the first folding knife 42. The trailing portion 29t of that towel is pushed back, or toward the entrance end of the folder, so that it laps over the folding knife 38, forming a creasein the towel at about its center. It is to be noted that in this action, the lower run 221 is traveling in reverse direction, or to the left as viewed in FIG. 3, and this fact assists in folding the towel over the first folding knife, i.e., the trailing portion 29! of the towel may actually engage the down run 221 of the conveyor and the latter by friction engagement therewith moves it down into lapped folded position over the first folding knife.

The folder is adapted to folding towels of two different sizes at the same position, i.e., at about the middle. Shop towels are ordinarily of 18 inches and 30 inches lengths, both of 18 inches width. When the longer towels are to be folded, the timing means times out over a longer period, and this is controlled by a manual switch 57 (FIG. 9).

The towels are then stacked on the first folding knife 38 in face-to-face position, and although they do assume somewhat of a folded position, they are not individually folded and they interengage throughout their full face areas. The folder includes counter means as referred to again hereinbelow in the electrical circuit, and upon its being set for a predetermined number, such as ten which is found to be a convenient number, the first folding knife 38 is moved to advanced position with the towels that have already been stacked thereon, and in making this folding operation, a novel folding step is performed, that is, in connection with the last towel to make up this stack, such as the tenth, instead of the second folding knife 46 performing the folding operation, the first folding knife 38 is advanced at such time as to catch the towel 29, as it is coming off of the inlet conveyor. Such a step is represented in FIG. 4 where the folding knife 38 catches the towel in mid-air and at a position about midway of that towel and that movement of the first folding knife 38 results in that towel being folded on the other towels into a bundle or stack now identified 54, and the fold or crease of the stack, now identified 56, is forced into the exit conveyor 24.

The exit conveyor 24 includes an upper endless belt 58 and a lower endless belt 60, each of which may be made of a plurality of belt elements 58a, 60a spaced apart and of a total width similar to the width of the shop towels. The upper conveyor belt 58 is longer and extends throughout, and determines the length of the exit conveyor 24 (FIGS. 1 and 3).

The

conveyor belt

58 and 60 form the bight 62 identified above and when the folded towels 23 are inserted thereinto by the first folding blade 38, the bundleor stack is gripped by the conveyor belts and are carried thereby and therebetween in exit direction as indicated by the arrow 64 (FIG. 3).

The conveyor belt 60 leads directly to a pair of flippers 66, which in themselves are known. These flippers are disposed directly under the belt elements 58a (FIG. 8) and as the stack of towels moves along between the belt means 58, 60 and pass beyond the conveyor belt 60, they move onto the flippers 66, the flippers having curved leading edges 68 (FIG. 2) to assist in moving the towels thereonto. The flippers are spaced below the conveyor belt 58 at a suitable distance to provide friction gripping of the towels for carrying them along the conveyor means 24.

A trigger means 70 (FIG. 1) which may be a finger of an electric switch 72, is arranged for engagement by the bundles as they pass along the conveyor means 24, and in response to an appropriate control the flippers are actuated to a releasing position shown in dot-dash lines in FIG. 8, releasing the bundle or stack, and the latter then falls onto a carry-off conveyor 74, this conveyor not necessarily being an integral part of the folding operation as such, but which may be incorporated in the physical structure of the folder for convenience.

The flippers 66 are operated by any convenient means, such as an air cylinder (FIG. 7) under the control of a solenoid valve 73 (FIG. 9) and acting through one of the shafts 77 on which the flippers are mounted, this shaft being rotated in a first direction and through a linkage mechanism 71, moves the other shaft in the opposite direction, thereby moving the flippers to releasing position.

After the towels are folded in a bundle or stack, they may be placed on a platform, or other convenient means for appropriate handling. The carry-off conveyor 74 is operated by a motor 76 and it may be operated intermittently, in accordance with the placement of the bundles or stacks thereon. The inlet conveyor 22 and the exit conveyor 24 are however operated continuously as is desired in the direction of simplicity of construction of the device, eliminating, as indicated above, the necessity for clutches and brakes in their operation. While the inlet conveyor 22 and the exit conveyor 24 are preferably driven by a common driving means, namely the motor 26 through the belt 28, the inlet conveyor 22 is driven at a much more rapid rate, through a relatively small pulley 78 while the exit conveyor 24 is driven through a relatively large pulley 80.

The inlet conveyor 22 is driven at such a rapid rate that it can carry off the towels that the operator in working at a predetermined desired pace, can place thereon in nearly edge-to-edge abutting relation and form substantially a continuous succession of towels. On the other hand the conveyor means 24 need only be driven at a much slower rate, and a in the case where the bundles or stacks contain ten each, the conveyor means 24 can theoretically be driven efficiently at onetenth the rate of the inlet conveyor 22. However as a practical matter the conveyor means 24 may be driven slightly faster than that, for convenience. It is also practical to have the exit conveyor 24 traveling at a more rapid rate, such as one-fifth the rate of the inlet conveyor 22, to accommodate those situations where it is desired that the bundle or stack have fewer than ten therein, such for example as five, etc. At any rate, the exit conveyor can be driven much slower than the inlet conveyor, all adding to the simplicity of the machine, because obviously the slower the speed at which the various parts are run, the more lasting it will be.

Reference is now made to the electrical circuit of FIG. 9. The circuit is connected with a suitable AC source having a pair of lines identified in the circuit as L-l andL-2, the various connections being indicated by posts shown as squares.

The bundles or stacks formed of the folded shop towels may contain ten, although it often occurs that the user would desire to have only five for example in such bundle. Switch means 82 is provided whereby the control may be set for providing either five or ten in a bundle, as indicated by the different positions of that switch. This switch controls a stepping switch 84 which in turn controls the actuation of the second folding knife (wigwag) according to the desired number in the bundle. in either case the second folding knife is held inactive at the last of the number, i.e., in the one case upon the fifth towel coming off the inlet conveyor, and in the other case the tenth towel. The stepping switch 84 acts through the solenoid valve 53, while the stepping switch itself is controlled by the PE cell 34 acting through the component surrounded in dot-dash lines 86.

The circuit also includes another stepping switch 88 which controls the solenoid valve 45 for controlling the first folding knife 38 and the solenoid valve 77 for the flippers. The flippers are actuated at each step in the stepping switch, pursuant to each towel passing therealong. The stepping switch 88 is controlled by the component shown in dot-dash rectangle 90 whereby upon a predetermined number of bundles being dropped from the flippers onto the carryoff conveyor, the motor 76 is actuated for advancing that conveyor.

The stepping switch 88 is further controlled by a manually settable switch 92 so that the motor 76 is actuated at the desired number of bundles being placed on the carry-off conveyor. For example associated with this switch are position indications 50 and 100, the former indicating five bundles and the latter ten bundles.

I claim:

1. A folder comprising,

an inlet conveyor,

stacking means for receiving towels thereon at the exit end of the inlet conveyor,

means for placing the towels on the stacking means in stacked condition wherein they are placed in face-to-face position,

an exit conveyor,

said stacking means includes a first knife and second knife, means for actuating the second knife in response to each of a plurality of towels on the first conveyor, and the second knife being operable for folding the towels over the first knife, and means actuating the first knife for forming the fold of the stacked towels periodically in response to a plurality of towels being folded over the first knife, means for moving the stacking means for moving the towels stacked thereon into the exit conveyor and in doing so, making a fold in the towels stacked thereon, and the last moving means and the exit conveyor cooperating to form a fold in the towels thus stacked as a single fold in which the towels so stacked are together folded in a single bundle.

2. A folder according to claim 1 wherein the first knife is under and adjacent the exit end of the inlet conveyor, the towels upon leaving the inlet conveyor drop by gravity, and the second folding knife engages each towel at a midpoint and moves the upper portion of the towel toward the exit end of the folder over the first knife and into folded position thereon.

3. A folder according claim 2 wherein the inlet conveyor has a lower return run directly adjacent the first folding knife, and the second folding knife moves the upper portion of the towel into friction engagement with the lower run and the latter aids in moving the upper portion of the towel over the first folding knife.

4. According to claim 2 and including means under the control of each towel as it moves along the inlet conveyor for controlling the actuation of the second folding knife.

5. A folder according to claim 4 in which the said control means includes a PE cell of retro-reflective type, and a target plate, and the towels as they move along the inlet conveyor pass between the PE cell and the target plate.

6. A folder according to claim 2 and including means manually settable according to a predetermined number of towels moving on the inlet conveyor, means under the control of said settable means for retaining the first folding knife stationary and for actuating the second folding knife in association with each of the towels of the set number except the last one, and operative in response to the movement of the last of that number of towels for deactivating the second folding knife and advancing the first folding knife, and the first folding knife being so advanced engages the last towel and produces a fold thereof over those previously folded thereon and effects folding of all of those towels together in conjunction with the exit conveyor.

7. A folder according to claim 1 wherein the exit conveyor includes an upper conveyor belt and flippers thereunder, the upper conveyor belt frictionally engages the towels and together with the flippers being operative for carrying the towels along the conveyor belt, and means actuated by the towels moving along the exit conveyor for actuating the flippers and releasing the towels and permitting them to drop therefrom.

of movement of the upper conveyor belt.

Claims

1. A folder comprising, an inlet conveyor, stacking means for receiving towels thereon at the exit end of the inlet conveyor, means for placing the towels on the stacking means in stacked condition wherein they are placed in face-to-face position, an exit conveyor, said stacking means includes a first knife and second knife, means for actuating the second knife in response to each of a plurality of towels on the first conveyor, and the second knife being operable for folding the towels over the first knife, and means actuating the first knife for forming the fold of the stacked towels periodically in response to a plurality of towels being folded over the first knife, means for moving the stacking means for moving the towels stacked thereon into the exit conveyor and in doing so, making a fold in the towels stacked thereon, and the last moving means and the exit conveyor cooperating to form a fold in the towels thus stacked as a single fold in which the towels so stacked are together folded in a single bundle.

8. A folder according to claim 7 in which the exit conveyor also includes a lower conveyor belt which with the upper conveyor belt form a bight operative in conjunction with the first folding knife for forming a fold of the stacked towels between those two conveyor belts and taking the bundle from the first folding knife, in the lower conveyor belt is of shorter length than the upper conveyor belt, and the flippers extend as a continuation from the lower conveyor belt in the direction of movement of the upper conveyor belt.