Claims
- 1. In a folding apparatus the combination comprising article folding means adapted to be mounted above a supporting surface; article sensing means; conveyor means for moving a foldable article at a constant speed between said article sensing means and said article folding means in a fixed period of time; said article sensing means being disposed adjacent the conveyor path and being sensitive to passage thereby of the article leading and trailing edges; control means adapted to be activated following receipt of a signal from said article sensing means while sensing a foldable article; said control means comprising a time/count control adapted to count out time at a normal rate and at a less than its normal rate; said control having a count entered therein corresponding to said fixed period of time; said time/count control emitting a signal for activating said folding means after said time/count control has counted out said count entered therein; the entered count being counted out at said rate less than its normal rate while activated by said article sensing means and said entered count being counted out at said normal rate following passage of the foldable item from engagement with said sheet sensing means; an AC time signal having positive and negative half wave pulses operating at a frequency of 60 cycles per second driving said time count control; said time/count control counting the positive half wave pulse only of said time signal during the interval the article sensing means senses the foldable article and thereafter counting both the positive and negative half wave pulses of said time signal until said time/count control has counted out the count entered therein.
- 2. In a method for imparting a fold to a predetermined portion of a foldable item while moving at a constant speed from an item sensor toward a folding means for effecting such fold in said item, the steps comprising measuring the time interval expended in the course of the leading edge of said item moving at such constant speed between said sensor and said folding means; entering counts equivalent to such time interval in a timer control for said folding means; said timer control being adapted to activate said folding means by means of a signal; activating said folding means by a signal from said timer control following reception of an energizing signal from said sensor after the passage of a time period equivalent to that time consumed by said predetermined portion of the foldable item to be folded moving past the sensor, combined with said entered time interval; driving said timer control during passage of said time period by means of an AC time signal having positive and negative half wave pulses and operating at a frequency of 60 cycles per second; said timer control counting one of said half wave pulses only during the interval the sensor means the foldable article and counting both of said half wave pulses during the remainder of the entered time interval until said time interval has been counted out of the time control.
- 3. In a folding apparatus the combination comprising article folding means adapted to be mounted over a supporting surface; article sensing means, an upwardly inclined conveyor means for moving a foldable article along an axis of movement at a constant speed between said article sensing means and said article folding means disposed at an upper conveyor discharge end in a fixed period of time; the angle of inclination of said conveyor and the height of said discharge end above said supporting surface being such that a leading foldable article portion comprising over one-half the length of said foldable article as measured along said conveyor axis of movement may drop by gravity from the discharge end of said conveyor and hang vertically while supported by said conveyor by means of a trailing foldable article portion thereon without dropping whereby wrinkles are removed from said foldable article leading portion; said article sensing means being disposed adjacent the conveyor path and being sensitive to passage thereby of the article leading and trailing edges; control means adapted to be activated following receipt of a signal from said article sensing means while sensing a foldable article; said control means comprising a time/count control adapted to count out time at a normal rate and at a less than its normal rate; said control having a count entered therein corresponding to said fixed period of time; said time/count control emitting a signal for activating said folding means after said time/count control has counted out said count entered therein; said entered count being counted at said rate less than its normal rate while activated by said article sensing means and counting out said entered count at said normal rate following passage of the foldable item from engagement with said sheet sensing means; a clock source, comprising an A.C. time signal driving said time/count control and operating at a constant frequency of 60 cycles per second; said source having the frequency thereof divided by two during the interval the article sensing means senses the foldable article whereby said counter is driven at half speed during said interval.
Parent Case Info
This invention relates to folding apparatus and is a continuation-in-part of my pending application Ser. No. 570,058, filed Apr. 21, 1975 now abandoned. More specifically, this application is directed to a folding apparatus of compact design adapted to efficiently form a plurality of folds in foldable items such as textile articles while occupying a minimum amount of valuable floor space in a place of use such as a laundry or the like.
A variety of folding apparatus for folding textile items is well-known in the art. However, quite often machines of the prior art although adapted to fold foldable items such as sheets a plurality of times are rather large and at times massive. Undesirable machine size has obvious disadvantages such as the occupying of large areas of valuable floor space. Also, if the machines are of excessive height, little room is available for a workman to maintain and repair the various moving apparatus elements, thereby rendering optimum machine operation a difficult matter.
Prior art folding devices such as that disclosed in Kamberg U.S. Pat. No. 3,361,424 although adapted to reliably form a plurality of folds in a foldable laundry item such as a bedsheet or the like, are rather large in exterior dimensions occupying a large floor area and room volume.
A main feature of the provided folding apparatus comprises a novel stacking mechanism used in conjunction with the various folding stations of the hereinafter described device. The provided stacking apparatus includes a single platform of spaced supporting fingers which is substantially instantaneously movable upon reception thereon of a folded textile article such as a bedsheet of the like which has been folded by the main apparatus elements.
Although the prior art has long employed stacking apparatus for use in conjunction with folding machines of the type hereinafter described, such stacking devices were normally of complex, expensive manufacture which included a large number of separate working parts not only contributing to the large initial cost, but also rendering maintenance of the same difficult and expensive.
By way of example, Junemann et al U.S. Pat. No. 3,414,138 discloses a device for automatically stacking workpieces in which a folded textile article is forceably moved through a series of movements by apparatus components, which move the folded article through various positions prior to stacking the same on a stacking platform. The folded article in Junemann is forced to follow a "quadrangular path" wherein a folded textile article is slidably moved unto the supporting rods whereafter the supported workpiece is stripped from the rods into a vertical stack.
Another relatively complex stacker apparatus is disclosed in Kamberg U.S. Pat. No. 3,361,424 which stacker employs a plurality of components for purposes of forming a stack able to be formed by the stacker hereinafter described in detail. The stacker hereinafter disclosed is composed of a minimum number of parts requiring little in the way of maintenance.
It is an object of this invention, therefore, to provide a folding apparatus employing a novel stacker which efficiently forms a plurality of folds in a foldable textile article such as a sheet or the like, as the sheet is rapidly conveyed through the various folding stations of the apparatus.
It is another object of this invention to provide a folding apparatus in which safeguards are provided throughout the passage of the foldable articles through the device, substantially completely obviating any danger of the foldable article jamming in various movable elements of the provided apparatus.
It is a still further object of this invention to provide a folding apparatus adapted to efficiently form a plurality of folds in a foldable textile article, which apparatus is compact in design, occupying a minimum amount of valuable floor space. The provided apparatus utilizes a small number of reliable parts of long life so that the resultant machine is extremely durable and extremely simple to maintain.
It is yet another object of this invention to provide a stacker of simplified design in which a single reciprocating platform in conjunction with a vertical stop surface is able to form a neat vertical stack of foldable articles upon receiving such articles discharged from the folding apparatus of the provided invention.
It is still another object of this invention to provide a folding apparatus employing novel actuating means for effecting folds in a moving foldable article, such actuating means being able to be precisely controlled so that an exact portion of the foldable article is always engaged by the folding means for purposes of forming the desired folds.
The above and other objects of this invention will become apparent from the following detailed description when read in the light of the accompanying drawings and appended claims.
In one embodiment of a folding apparatus made in accordance with this invention, the edge of a foldable article such as a sheet or the like, is fed onto a constant-speed feed conveyor which is upwardly inclined at an angle of approximately 28.degree. from the horizontal. In the course of being fed onto the initial portion of the feed conveyor the sheet passes over an electric eye, thereby actuating a time/count control, such control being deactivated for sheet measurement upon passage of the sheet terminal edge over said eye. The length of the sheet is precisely calculated in terms of the counts or time it takes the feed conveyor to move one-half of such sheet over the electric eye. This time comprises a "delay" added to the time expended for a point on the feed conveyor to move from the electric eye to an air bar adapted to emit a blast of air for sheet-folding purposes. Thus the control actuates a solenoid to allow air passage into the air bar when the sheet mid-point is precisely opposite such bar.
Accordingly, as the foldable article moved by the constantly moving feed conveyor drops from the raised terminal end of such feed conveyor, the air bar disposed adjacent such feed conveyor terminal end and adjacent the beginning of an underlying second conveyor feed end is activated by the control to drive the mid-point of the conveyed sheet onto the second conveyor which is angled downwardly toward the initial feed station.
A second air bar is disposed at the lower end of the second conveyor. In the course of moving onto the second conveyor, a switch actuator is tripped by the leading edge of the half-folded sheet which is in communication with a second time/count control which effectively measures one-half the length of the half-folded sheet in terms of counts. The length measurement is terminated when the trailing edge of the half-folded sheet leaves engagement with such switch.
When the mid-point of the half folded sheet drops from the terminal end of the second conveyor beneath the initial feed end of the apparatus, an appropriately positioned air bar drives the mid-point of such half-folded sheet onto a third conveyor moving to the rear of the apparatus.
The flexible article which has now been twice transversely folded engages an actuating switch in the course of movement over the third conveyor thereby activating a brake for the third conveyor, and while the twice folded sheet is at rest, an air bar disposed over the twice folded sheet drives the transverse mid-point of the same down between counter-rotating pinch rolls for discharge unto an underlying fourth conveyor which moves the thrice folded sheet transversely of the apparatus upper conveyors toward a discharge opening. In the course of moving on the fourth conveyor the thrice-folded sheet engages two series of buckling folders which engage the leading edge of such textile article and drop the same on the trailing edge as the same is moved by the fourth conveyor so that the finally discharged foldable article has been folded five times.
Such folded article is driven from the end of the fourth conveyor onto an underlying stacking platform comprising spaced supporting fingers. In the course of slidably moving over the supporting fingers an actuating switch arm is tripped, substantially instantaneously retracting the supporting fingers. The leading edge of the final folded article slides toward a stop surface as the supporting fingers are withdrawn from therebeneath. Such action allows the folded article to drop in substantially the vertical plane with its forward edge aligned by the stop surface disposed at substantially right angles to the axes of the reciprocating fingers. The underlying articles may be stacked on an automatic conveyor which is actuated to move the formed stack after a predetermined number of reciprocations of the stacking platform, toward the operator who is feeding the articles onto the apparatus at the feed station.
US Referenced Citations (15)
Continuation in Parts (1)
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570058 |
Apr 1975 |
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Patent Grant
4073486
