US3410048A - Shrink wrap apparatus - Google Patents

Description

NOV. 12, 1968 GOTTILY ET AL 3,410,048

SHRINK WRAP APPARATUS 2 Sheets-Sheet 1 Filed May 25, 1965 INVENTORS ARTHUR L. GOTTILY JOHN L.THOMAS BY am .2630

AGENT NOV. 12, 1968 GQTTILY ET AL 3,410,048

SHRINK WRAP APPARATUS 2 Sheets-Sheet 2 Filed May 25. 1965 INVENTORS ARTHUR L. GOTTILY JOHN L. THOMAS AGENT United States Patent Office 3,410,048 Patented Nov. 12, 1968 3,410,048 SHRINK WRAP APPARATUS Arthur L. Gottily and John L. Thomas, Pensacola, Fla.,

assrgnors to Monsanto Company, St. Louis, Mo., a corporation of Delaware Filed May 25, 1965, Ser. No. 458,679 11 Claims. (Cl. 53-77) ABSTRACT OF THE DISCLOSURE Shrink wrapping or bagging apparatus including a thermally controlled oven and a reciprocating carrier adapted to carry items covered with shrink wrap material into and out of the oven.

A conventional shrink wrap packaging machine, in general, comprises a horizontally moving endless conveyor and an oven positioned over the conveyor. Merchandise wrapped in thermoplastic shrink material is placed on the conveyor and is carried through the thermally controlled oven. Some disadvantages are apparent when conventional conveyor type machines are used to shrink wrappers for bags or bobbins packaged with yarn. The yarn packages, usually precision wound and containing high quality yarn, are often damaged by the handling required and the apparatus used. The bobbins must be laid on their sides on rollers or belts of the conveyor whereby the tightly wound yarn wraps of the packages sometimes become loose and the packages lose their symmetry. Also, shrinkage of covers upon a package is not always uniform because a portion of the cover is always in contact with the conveyor or belt and, therefore, is not exposed to the same thermal condition as the rest of the cover when moving through the oven. Another disadvantage is that conventional apparatus is not compact, requires several operators, and occupies a large amount of floor space.

It is an object of this invention to provide an upright reciprocating textile shrink wrap apparatus with safety features.

Another object of this invention is to provide shrink wrap or bag apparatus for wrapping goods with shrinkable thermoplastic materials.

Another object is to provide upright cabinet shrink wrap apparatus.

A further object is to provide a textile shrink Wrap machine adapted to automatically deliver a plurality of bobbins packaged with yarn and covered with shrinkable material into a thermal zone and to remove the bobbins therefrom after a controlled period.

The novel shrink wrap apparatus, in brief, comprises a thermally controlled'oven means and an automatic reciprocable bobbin carrying means adapted to carry a plurality of bobbins covered with thermoplastic shrink material into the oven for a pre-set controlled time for shrinking the material about the bobbins and to subsequently remove the bobbins therefrom.

A better understanding of the apparatus of the invention will be gained by reference to the following more detailed description and to the attached drawings. In the drawings,

FIGURE 1 is a side elevation view of the novel shrink wrap apparatus with parts broken away to show the various components thereof;

FIGURE 2 is an isometric view of part of the bobbin lift means with parts broken away; and

FIGURE 3 is a front elevation view of the novel shrink wrap apparatus with parts broken away to more clearly illustrate the components thereof.

In the several figures in the drawing the same reference numerals are used to identify like components.

Referring to the drawings, FIGURES 13, the novel shrink wrap machine 1 embodying the invention illustrated in one form comprises a frame assembly 2 supporting a thermally controlled shrink oven assembly 3 above an automatic bobbin reciprocating assembly 4. The oven assembly 3 and the reciprocating assembly 4 are supported on the frame assembly 2 to provide an upright cabinet presenting a front side with electrical controls conveniently located for an operator of the machine.

The shrink oven assembly 3 comprises a housing 5 having insulatably lined side, upper and lower walls defining an enclosed oven volume or space. Within the oven space there are a plurality of plenum enclosures 6 defining a plurality of plenum chamber 7. Plenum enclosures 6 are, preferably, separately divided units and are spaced from the side walls of housing 5 and have a plurality of openings or slots 8 therein and adjustable louvers (not shown) adjustably secured to the enclosures 6 adjacent slots 8 for controlling flow of heated air to the interior thereof. Access to each of the plenum chambers 7 through the bottom wall of housing 5 is provided by respective pivotal doors 10 each hingedly connected to the bottom of the back side of housing 5 and swingable inwardly of the plenum chambers 7. Preferably, each door 10 has a wear plate at its exterior side thereof.

Above and spaced from the plenum enclosures 6 is a fixed horizontal shroud plate 12 with a central aperture 13. A fan 14 is coaxially aligned with and positioned adjacent aperture 13. Fan 14- is driven by a shaft 15 extending through housing 5 and connected to motor 16 mounted on housing 5 and connected to a source of energy.

Between and in spaced relation from shroud plate 12 and plenum enclosures 6, heat resistance wires 17 suitably mounted to housing 5 and connected to a source of energy provide heating units. When fan 14 is rotating, air flows past the resistance wires, is heated, and flows in surroundment of and into the plenum chambers 7 through slots 8 of the plenum enclosures 6. A plate 18 depends in the manner of a curtain from the upper wall of housing 5 at the back side of the plenum enclosures 6 and serves to direct air flowing from the plenum chambers 7 to a zone above the shroud plate 12. The climate within the oven is controlled by a thermostat 19.

The reciprocating lift assembly 3 comprises a pair of reciprocable spaced bars 20 having a plurality of roller assemblies 21 mounted in spaced distances along the length thereof. Roller assemblies 21 contact, ride on, and connect each bar 20 to a respective frame rail 22. Each bar 20 has a plurality of spaced aligned spindles or pegs 23 extending angular-1y, upwardly and outwardly therefrom and is positioned below a respective door 10. Pegs 23 are aligned in a vertical plane below a corresponding door 10. At the upper end of each bar 20, a series of off-set rollers 24 roll against and open and close door 10 when bar 20 is actuated into and out of a plenum chamber 7. By arranging rollers 24 one behind the other and off-setting their height with the highest placed nearest the front of a door 10 the latter can be fully opened and closed in a smooth operation.

The reciprocable bars 20 move up and down rails 22 by means of a chain drive transmission 25. Transmission 25 include a motor 26 connected to an energy source and a drive gear 27 connected to the shaft of motor 26. A pair of driven gears 28 each connected to one end of a drive gear shaft 29 mesh with and are driven in opposite directions by drive gear 27. Each driven gear shaft 29 at its end opposite the driven gear has a sprocket 30 fixed thereto. Interposed in each driven gear shaft 29 is an electromagnetic clutch 31. Electromagnetic clutches 31 are controlled by off-on switches 32 and microswitches 33 and microswitch actuators 34 located substantially at the top and bottom of each bar 20. Each driven gear shaft 29 has a brake clutch 35 of conventional type mounted thereon for permitting shafts 29 to rotate in one direction only for braking shaft 29.

Below and in the same vertical plane of each sprocket 30 there is a corresponding lower sprocket 36 rotatably mounted on frame assembly 2 and a link chain 37 is mounted to travel around corresponding upper and lower sprockets 30 and 36.

Each bar 20 has a counterweight 38 connected thereto by means of a chain and movable over a pulley mounted on the frame 2 for stabilizing movement of bar 20.

Adjacent the lower end of each bar 20 is a slotted cam plate 40 aflixed thereto and a cam roller 41 is positioned within the cam slot. Each cam roller 41 has a pin 42 extending therefrom and pin 42 extends through and connects with a pair of links of a corresponding chain 37.

The shrink wrap machine cabinet, preferably, has a table surface at the front side thereof below the oven for the convenience of an operator. Several air jets 43 connected to a source of pressurized air are provided near the table. In the illustrated embodiment, the jets 43 are located adjacent the open ends of supported folded thermoplastic bags 46 and the air flowing from jets 43 inflates or expands and thus prepares the bags 46 for an operator prior to bagging a bobbin 45.

In operation, the motor 16 switch, the motor 26 switch and the heater 17 switch all located on a control panel 44 are actuated to the on position for driving fan 14, driving gear 27, and heating wires 17, respectively. The electromagnetic clutches 31 are not energized at start-up and therefore both gears 28 will be driven but shafts 29 will be disconnected therefrom.

The oven is readily heated to the preset temperature as controlled by thermostat 19. Fan 14 circulates air past resistance wires 17 and the heated air circulates around and into the plenum enclosures through slots 8. The separate plenum chambers 7 provide independent stabilized thermal zones. The heated air leaves the plenum chambers 7 through the back sides thereof, is deflected to the space above shroud plate 12 by plate 18, and is recirculated in the same path described.

For purposes of simplicity, the operation of one reciprocable bar 20 will be expalined only; however, it will be understood that both bars 20 may be operated simultaneously, separately or sequentially. The operator then loads a packaged bobbin 45 on each of the pegs 23 On bar 20. Bobbins 45 are hollow and easily mounted on the upwardly angled pegs 23. The operator next takes an expanded shrink bag 46 from a stack located about the cabinet table and places the bag over the packaged bobbin 45 mounted on a peg 23. Next, after loading bar 20 with bobbins and covering them with shrink bags, the operator actuates off-on switches 32 on the cabinet to close a circuit connected to a corresponding electromagnetic clutch 31. The clutch 31, being energized, connects shaft 29 to the shaft of motor 26 through gears 27 and 28 and chain 37 is driven in a clockwise direction (FIG- URE 2). Since bar 20 is connected to chain 37 through the cam roller 41, bar 20 is lifted into a corresponding plenum chamber 7. Door of the oven assembly 3 is pivotally opened by the roller assembly 21. As bar moves into the plenum chamber 7, the rollers of roll assembly 21 push door 10 wide open and bobbins 45 are carried into the plenum chamber 7. When bar 20 reaches an upper limit position with all of the bobbins 45 in the oven, a microswitch actuator 34 contacts a microswitch 33. The microswitch 33 is connected to a delay circuit 48 such as a resistance capacitor and a relay network or R-C circuit connected to the electromagnetic clutch 31 for deenergizing clutch 31 and thereby discontinuing the movement of bar 20 upward. Bar 20 is held in its upward limit position by the cam brake clutch preventing rotation of shaft 29 in a counter-clockwise direction. Bobbins are kept in the oven for a pre-set dwell time by the delay circuit while the bags are shrunk on the bobbins. The R-C circuit then energizes clutch 31 so that chain 37 is driven and bar 20 is lowered bringing the shrink wrapped bobbins out of the plenum chamber 7. When bar 20 reaches a predetermined lower position, another microswitch actuator 34 contacts a lower microswitch 33 mounted on the frame which denergizes clutch 31 to disconnect shaft 29 from the shaft of motor 26 and to stop bar 20 in its lower or load position. The packaged and shrink wrapped bobbins are then removed and the machine 1 is ready for a repeat operation.

For safety reasons, if a bobbin is not mounted properly on a peg 23 and the bobbin projects therefrom a distance such as to prevent its entrance into the oven, photocells 50 are provided near the entrance to the oven to detect the unsafe condition and to break a circuit to the electromagnetic clutch for stopping operation.

It will be noted that when motor 26 is operating, both gears 28 are driven by gear 27, one in one direction and the other in the opposite direction and that both bars 20 can carry a load of bobbins into the oven simultaneously, if desired, by actuating respective off-on switches 32.

The novel upright shrink wrap machine is compact and offers a way of shrink wrapping bobbins with a minimum of yarn package contact from machine or handler.

It will be understood that variations and modifications of the illustrated embodiment are expected within the scope of the invention and that limitations are only contemplated within the spirit of the following claims.

We claim:

1. A textile shrink wrap apparatus comprising.

(a) an upright frame,

(b) a housing defining a plurality of oven plenum chambers and supported topside on said frame,

(c) means for thermally controlling said oven temperature,

(d) a plurality of movable closure means secured to said housing and providing access through the bottom of said housing to each of said plenum chambers,

(e) a plurality of reciprocable means mounted on said frame and adapted to carry a plurality of bobbins wrapped in shrink material into and out of said plenum chambers and to open and close said movable closure means,

(f) means for actuating said reciprocable means,

(g) timing means for controlling said plurality of reciprocable means to provide a predetermined dwell time of said bobbins in said plurality of plenum chambers, and

(h) means for actuating said plurality of reciprocable means separately or in unison.

2. A textile shrink wrap apparatus as in claim 1 further comprising safety means for stopping reciprocation of any one of said plurality of reciprocable means when unsafe conditions prevail.

3. Shrink wrap apparatus comprising in combination:

(a) means defining an oven having a single entranceexit opening thereto,

(b) means for heating said oven,

(c) means for supporting at least one article wrapped in shrink material and for reciprocating the same into and out of said oven through said single opening,

(d) movable cover means closing said opening, and

(e) means for controlling the opening and closing of said movable cover means in cooperation with the reciprocating of said article into and out of said oven.

4. Shrink wrap apparatus as in claim 3, wherein said means for supporting said article is adapted to axially support at least one textile bobbin.

5. Shrink wrap apparatus as in claim 3, wherein said opening is at the bottom of said oven and said reciprocable means is vertically operable.

6. Shrink wrap apparatus as in claim 3, wherein said movable cover means is a pivotal cover, and said means for controlling said pivotal cover is carried on said reciprocable means.

7. Shrink wrap apparatus as in claim 3, comprising means for controlling said reciprocable means to provide a predetermined dwell time of said at least one article in said oven.

8. Textile shrink wrap apparatus comprising in combination:

(a) means defining an oven having a plurality of plenum chambers each having a single entrance-exit opening at the bottom side thereof,

(b) means for heating said oven,

(c) movable cover means closing each of said entranceexit openings,

((1) a plurality of reciprocating means each adapted to support at least one textile bobbin and each being vertically reciprocable to carry textile bobbins into and out of said plenum chambers through said openings,

(e) means for actuating said reciprocating means, and

(f) means for controlling the opening and closing of said movable cover means in cooperation with the reciprocating of said textile bobbins into and out of said plenum chambers.

9. Textile shrink wrap apparatus as in claim 8, comprising means for actuating said plurality of reciprocating means separately or in unison.

10. Textile shrink wrap apparatus comprising:

(a) an oven having an entrance-exit opening at the bottom side thereof,

(b) means for heating said oven,

(c) a pivotal closure means covering said opening,

(d) reciprocable means adapted to carry at least one textile bobbin Wrapped in shrink material into and out of said oven and having means for cooperatively opening and closing said pivotal closure means, and

(e) means for actuating said reciprocable means.

11. Textile shrink wrap apparatus comprising in combination:

(a) an oven having a plurality of plenum chambers each having a single entrance-exit opening at the bottom side thereof,

(b) means for heating said oven,

(0) movable cover means closing each of said entranceexit openings,

(d) a plurality of reciprocating means each adapted to support at least one textile bobbin and each being vertically reciprocable to carry textile bobbins into and out of said plenum chambers through said openings,

(e) means for actuating said reciprocating means, and

(f) means for controlling the opening and closing of said movable cover means in cooperation with the reciprocating of said textile bobbins into and out of said plenum chambers.

References Cited UNITED STATES PATENTS 1,904,580 4/1933 Van Nordstrand 219388 30 TRAVIS S. MCGEHEE, Primary Examiner.

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