US3923594A

US3923594A - Method for forming molded fiber products with deckle-free windows

Info

Publication number: US3923594A
Application number: US481851A
Authority: US
Inventors: Henry A Lord
Original assignee: Diamond International Corp
Current assignee: PACKAGINING Corp OF AMERICA A DE CORP; Packaging Corp of America
Priority date: 1972-06-19
Filing date: 1974-06-12
Publication date: 1975-12-02
Anticipated expiration: 1992-12-02

Abstract

Apparatus and method for forming deckle-free windows or openings in molded fiber products such as cartons, trays and the like, said apparatus comprising an air distributor manifold box with jet tubes whereby a blast of air may be directed against a blockout patch to lift deckle therefrom. The manifold box is movable to a discharge position and in contact with a switch which is operable to open a solenoid valve in a fluid conduit which connects said manifold box to an air accumulator tank, the operation of said apparatus providing the method of removing deckle from the surface of block-out patches disposed on forming molds to form windows. The method includes removing deckle from the surface of block-out patches by an air jet and pressing the up-lifted deckle into surrounding fiber portions to reinforce said surrounding portions.

Description

United States Patent WINDOWS [75} Inventor: Henry A. Lord, Cape Elizabeth,

Maine [73] Assignee: Diamond International Corporation.

New York, NY.

[22] Filed: June 12, 1974 [21] Appl. No.: 481,851

Related US. Application Data [62] Division of Sen No. 264,190. June 19, 1972, Pat. No.

[52] US. Cl. 162/195; 162/208; 162/227; 162/228; 162/286; 162/291 [51] Int. Cl. 021,] 3/00 [58] Field of Search 239/553, 562, 565, 566, 239/569; 162/228, 227, 208, 195, 286, 387, 388, 391, 396, 399, 400; 249/66 A [56] References Cited UNITED STATES PATENTS 2,320,789 6/1943 Montague et al 162/195 2,760,412 8/1956 Lemieux 162/228 Lord 1 Dec. 2, 1975 [5 METHOD FOR FORMING MOLDED FIBER 3.046.187 7/1962 Leitzel 162/228 PRODUCTS WITH DECKLEJREE 3,567.575 3/1971 Emergy 1, 162/387 Primary Erunziner-Robert L. Lindsay. Jr. Assistant E.raminerRichard V. Fisher Attorney, Agent, or Firm-Karl W. Flocks [57] ABSTRACT Apparatus and method for forming deckle-free windows or openings in molded fiber products such as cartons, trays and the like. said apparatus comprising an air distributor manifold box with jet tubes whereby a blast of air may be directed against a block-out patch to lift deckle therefrom. The manifold box is movable to a discharge position and in contact with a switch which is operable to open a solenoid valve in a fluid conduit which connects said manifold box to an air accumulator tank, the operation of said apparatus providing the method of removing deckle from the surface of block-out patches disposed on forming molds to form windows. The method includes removing deckle from the surface of block-out patches by an air jet and pressing the up-lifted deckle into surrounding fiber portions to reinforce said surrounding por- 4 Claims, 6 Drawing Figures US. Patent me. 2, 1975 Sheet 1 of 2 3,923,594

US. Patent Dec. 2, 1975 Sheet 2 of2 3,923,594v

I l5 l9 all/Ill tm m m w nmmvamau METHOD FOR FORMING MOLDED FIBER PRODUCTS WITH DECKLE-FREE WINDOWS This is a division of application Ser. No. 264,190,

filed June 19, 1972, now US. Pat. No. 3,871,586.

BACKGROUND OF THE INVENTION 1. Field of the Invention The field of the invention is believed to encompass art found in Class 162, subclasses 227 and 286.

2. Description of the Prior Art In the production of molded fiber products it is frequently desirable to form one or more apertures or windows therein, in particular in cartons or trays. The windows are formed by providing the forming molds with non-porous block-out patches or blocks. Concomitant with the use of block-out patches there is a build-up of undesirable fiber, known as deckle, around the edge of the windows. The removal of this undesirable fiber or deckle has been approached in the past, for example, by the application of water sprayed in the area to remove the deckle. The use of water spray to remove deckle has not been altogether satisfactory in that:

A. stray fibers frequently remain around the edge of the windows,

B. thickness of pulp formation in the window area may be adversely thinned out,

C. pulp furnish in machine vat may be diluted, and

D. manufacturing time is undesirably extended.

Other approaches for removing deckle include the use of air as disclosed in US. Pat. No. 2,923,654 to Comstock. It is noted that Comstock uses air in the vac: uum forming die to remove deckle. The specific approach of Comstock complicates the die construction, die changing on the machine, and machine construction. Its practical use is for a very small area on a special purpose machine.

SUMMARY OF THE INVENTION The present invention relates to improvements in an apparatus and a process for use in forming molded fiber products with windows therein. In particular, it is an object of this invention to provide an apparatus and method for forming molded fiber products with decklefree openings or windows therein having edges with clean lines.

It is also an object of this invention to form a molded fiber product with windows therein having reinforced edges there around.

It is additionally an object of this invention to provide an apparatus and method for increasing the speed of manufacturing deckle-free windows in molded fiber products.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of the apparatus according to the present invention shown in use in conjunction with a molded fiber product molding machine;

FIG. 2 is a fragmentary view looking at the top of the forming mold just after pulp has been applied thereto;

FIG. 3 is a sectional view taken along line 3 3 in FIG. 2;

FIG. 4 is a view similar to FIG. 3 showing portions of jet tubes rotated 90 from the position in FIG. 1 for convenience;

FIG. 5 is a view similar to FIG. 4 showing a fragmentary portion of a pressing mold applied against the uplifted deckle; and

FIG. 6 is a fragmentary top plan view of a molded fiber product preform with deckle-free windows.

DETAILED DESCRIPTION OF THE APPARATUS ACCORDING TO THIS INVENTION Referring now particularly to FIG. 1, the apparatus according to the present invention is shown in use in conjunction with a rotating molded fiber product molding machine 10. The molding machine 10 comprises a rotating wheel 12 which carries a plurality of forming molds 14, 14', etc. Each forming mold as shown is provided with a plurality of generally flat, non-porous block-out patches 15 for the formation of windows. As shown, the rotating wheel 12 continuously moves each forming mold into a vat V of pulp slurry and thereafter adjacent an air distributor manifold box 20, below a pressing mold 16 and finally to a conveying belt 18 upon which preforms may be taken to a drying oven, for example.

The apparatus according to the present invention comprises the air distributor manifold box 20 which is provided with a plurality of jet outlet tubes 22 on one face thereof and a flexible hose 30 connected to the opposite face thereof. As shown in FIG. 1, air distributor manifold box 20 is fixedly connected to support link 24 for pivotal movement about pin 26. A microswitch mechanism 28 is fixedly disposed on the molding machine side of the support link 24. Flexible hose 30 is connected to a high pressure air accumulator tank 34. A solenoid operated valve 32 is disposed in the circuit of the flexible hose 30 between air distributor manifold box 20 and high pressure air accumulator tank 34. Upon movement of support link 24 from the phantom position to the solid position and into contact with microswitch 28, which is electrically connected to the solenoid of valve 32, the valve 32 will be opened to allow a burst of air to tank 34, through hose 30, into box 20 and out tubes 22.

On the upstream side of accumulator tank 34 compressed air is supplied thereto by way of pipe 36 in which there is provided an air pressure regulator valve 38. Air, for example, may be supplied in pipe 36 at lbs. p.s.i. It is important that the diameter of pipe 36 be substantially smaller than that of discharge hose 30, so that the high pressure air is quickly dissipated to allow retraction of the air jet tubes without delamination of pulp in the area of the windows that are formed. In this connection pipe 36 might conveniently have a diameter of Va inch compared to a /4 inch diameter for hose 30. It is also noted that air tank 34 may be provided with an air pressure gauge 40 to determine the pressure therein.

METHOD AND OPERATION OF THE APPARATUS TO FORM DECKLE-FREE WINDOWS In conjunction with the operation of the present invention the molding wheel 12 of molding machine 10 is rotated in the counter-clockwise direction as shown in FIG. 1 whereby each of the forming molds 14 are immersed in the fiber Vat V and coated with a pulp slurry.

As the forming mold l4 emerges from the pulp vat the forming mold 14 will be covered with a pulp slurry 19. The non-porous block-out patches 15 on the mold 14 will have its edges surrounded by deckle 21. As clearly seen in FIG. 3 forming mold 14 is lined with a screening wire 17 upon which a plurality of spaced apart nonporous block-out patches 15 are disposed to form windows in the molded product and deckle portions 21 are superimposed over the edges of the patches 15.

As the forming mold 14 moves to a generally vertical position as shown in FIG. 1 support link 24 is moved from the position shown in phantom to the solid line position in which air distributor manifold box extends generally parallel to mold l4 and at which time support link 24 strikes microswitch mechanism 28 which opens solenoid operated valve 32 to allow a burst of air from accumulator tank 34 to pass through flexible hose 30 into air distributor box 20 and discharge through jet tubes 22 and against block-out patches 15. Each jet tube 22 is directed against the center of a patch 15 whereby a blast of air A sweeps across the face of each patch 15 to lift the deckle 21 off the patch and into upstanding position as shown in FIG. 4.

After the deckle 21 around each patch 15 is blasted into the upstanding position support link 24 is backed away to the phantom position shown in FIG. 1 and out of engagement with microswitch 28 whereby the solenoid operated valve 32 closes to permit build-up of air pressure in accumulator tank 34 for the next cycle. At the same time mold 14 continues in the counterclockwise direction to a position beneath a pressure mold 16, such as a wet press head, for example, which is lowered in mating relationship with forming mold l4 and thereby compressing the upstanding deckle 21 against the pulp portions 19 as shown in FIG. 5.

Upon this engagement of

molds

14 and 16, the fiber product preform 23 is formed with deckle-free windows having clean smooth lines and surrounding portions 19 with reinforced pressed-together portions 21 surrounding the windows as illustrated in FIG. 6.

It will be obvious to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown in the drawings and described in the specification.

I claim:

1. The method of forming deckle-free windows in molded fiber products comprising the steps of:

a. applying pulp slurry on a forming mold provided with one or more block-out patches for forming one or more windows in the finished product;

b. moving said forming mold with pulp slurry applied thereon to a deckle removing position whereby deckle formed on said one or more block-out patches may be removed therefrom; and

0. moving an air distributor manifold box with one or more jet tubes into very close proximity to said block-out patches and discharging high pressure air through each of said jet tubes against each of said block-out patches thereby blasting deckle off the top of each block-out patch, said high pressure air being discharged through said jet tubes with each of said jet tubes directed over the center of a blockout patch associated therewith whereby the air emitting from each jet tube strikes the top of the block-out patch and moves radially outwardly thereacross to sweep the deckle therefrom and over surrounding pulp portions clear of the blockout patch.

2. The method as recited in claim 1 wherein said pulp slurry is applied to said forming mold as it is moved.

3. The method as recited in claim 2 wherein said forming mold is moved in a continuous motion and said air distributor manifold box is moved alternately to and from discharging positions thereof to allow for pressure build-up in an accumulator therefor.

4. The method as recited in claim 3 in combination with further steps of moving said forming mold to a pressing position and forceably pressing said blasted deckle down against and into pulp portions clear of the

Claims

1. THE METHOD OF FORMING DECKLE-FREE WINDOWS IN MOLDED FIBER PRODUCTS COMPRISING THE STEPS OF: A. APPLYING PULP SLURRY ON A FORMING MOLD PROVIDED WITH ONE OR MORE BLOCK-OUT PATCHES FOR FORMING ONE OR MORE WINDOWS IN THE FINISHED PRODUCT; B. MOVING SAID FORMING MOLD WITH PULP SLURRY APPLIED THEREON TO A DECKEL REMOVING POSITION WHEREBY DECKLE FORMED ON SAID ONE OR MORE BLOCK-OUT PATCHES MAY BE REMOVED THEREFROM; AND C. REMOVING AN AIR DISTRIBUTOR MANIFOLD BOX WITH ONE OR MORE JET TUBES INTO VERY CLOSE PROXIMITY TO SAID BLOCK-OUT PATCHES AND DISCHARGING HIGH PRESSURE AIR THROUGH EACH OF SAID LET TUBES AGAINST EACH OF SAID BLOCK-OUT PATCHES THEREBY BLASTING DECKLE OFF THE TOP OF EACH BLOCK-OUT PATCH, SAID HIGH PRESSURE AIR BEING DISCHARGED THROUGH SAID JET TUBES WITH EACH OF SAID JET TUBES DIRECTED OVER THE CENTER OF A BLOCK-OUT PATCH ASSOCIATED THEREWITH WHEREBY THE AIR EMITTING FROM EACH JET TUBE STRIKES THE TOP OF THE BLOCK-OUT PATCH AND MOVES RADIALLY OUTWARDLY THEREACROSS TO SWEEP THE DECKLE THEREFROM AND OVER SURROUNDING PULP PORTIONS CLEAR OF THE BLOCK-OUT PATCH.

1. The method of forming deckle-free windows in molded fiber products comprising the steps of: a. applying pulp slurry on a forming mold provided with one or more block-out patches for forming one or more windows in the finished product; b. moving said forming mold with pulp slurry applied thereon to a deckle removing position whereby deckle formed on said one or more block-out patches may be removed therefrom; and c. moving an air distributor manifold box with one or more jet tubes into very close proximity to said block-out patches and discharging high pressure air through each of said jet tubes against each of said block-out patches thereby blasting deckle off the top of each block-out patch, said high pressure air being discharged through said jet tubes with each of said jet tubes directed over the center of a block-out patch associated therewith whereby the air emitting from each jet tube strikes the top of the block-out patch and moves radially outwardly thereacross to sweep the deckle therefrom and over surrounding pulp portions clear of the block-out patch.

4. The method as recited in claim 3 in combination with further steps of moving said forming mold to a pressing position and forceably pressing said blasted deckle down against and into pulp portions clear of the block-out patch.