US2730043A

US2730043A - Squeegees

Info

Publication number: US2730043A
Application number: US243895A
Authority: US
Inventors: Louft Nathan
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-08-27
Filing date: 1951-08-27
Publication date: 1956-01-10
Anticipated expiration: 1973-01-10

Description

Jan. 10, 1956 N. LOUFT 2,730,043

SQUEEGEES Filed Aug. 27. 1951 u INVENTOR Naiharz Loufl' ATTORNEY United States Patent SQUEEGEES Nathan Louft, Silver Spring, Md.

Application August 27, 1951, Serial No. 243,895

2 Claims. (Cl. 101-423) This invention relates to screen process printing machines and more particularly a new and novel squeegee for the same.

One of the objects of this invention resides in the provision of a squeegee device for screen process printing machines adapted to evenly spreada printing material such as paint or ink placed on the screen in advance of the squeegee blade and carry the surplus thereof over the screen to the initial point of contact of the squeegee blade with the screen for repeated use in printing.

Another object of this invention resides in the provision with a rubber squeegee blade of a gravity operated paint or ink collecting, depositing and distributing means for dropping or dumping the paint or ink onto the screen in front of the squeegee blade immediately at the beginning of the printing stroke.

A further object of this invention resides in the provision of means for adjustably securing the squeegee to the operating means for conveying it over the printing screen.

A still further object of this invention resides in the provision of means adapted to lock the paint or ink spreading member in inoperative position relative to the squeegee blade.

Among the many objects of this invention is the par ticular construction of the squeegee device with paint or ink depositing and spreading means.

With these and other objects in view, this invention resides in certain novel features of construction and arrangement of elements to be hereinafter more particularly set forth in the specification, illustrated in the accompanying drawing, and pointed out in the appended claims and, although this disclosure depicts my present conception of the invention, the right is reserved to resort to such departures therefrom as come within the scope of the claims.

In the accompanying drawing forming a part of this application;

Figure 1 is a plan view of the upper portion of a screen process printing machine with a squeegee device in accordance with the present invention;

Fig. 2 is a longitudinal sectional view taken through the upper portion of a screen process printing machine approximately on line A-A of Fig. 1 showing the squeegee device in full lines and operating against the printing screen and in dotted lines as returning to operative position relative thereto.

Fig. 3 is an enlarged sectional view taken approximately on line 3-3 of Fig. 1.

Fig. 4 is a view similar to that shown in Fig. 3 with the squeegee device returning to operative position.

Fig. 5 is a perspective view of the squeegee device showing the trough locked in inoperative position.

In the present illustration of this invention, the letter A designates the table of a conventional screen process printing machine which includes laterally spaced and longitudinally extending conveyor chains B trained over sprockets C supported by brackets D secured to the table on opposite sides of a movable printing frame F carrying the printing screen S and driven by suitable power means (not shown).

Connected to the aforesaid conveyor chains B is a cross bar K provided with depending studs L on which is adjustably and removably secured my squeegee device herein indicated, in general, by the numeral 5.

The squeegee device, as best shown in Figures 3-5 comprises a laterally extending rubber blade 6 having elongated front and

rear metal plates

7 and 8 secured along its upper edge portion by screws 9 or the like. Said front plate 7 is provided with an elongated angular flange 10 extending forwardly therefrom and side ears 11 projecting from its opposite ends while the aforesaid rear plate 7 is provided with laterally spaced and rearwardly extending brackets 12 having bores 13 intersected by thumb screws 14 to secure the squeegee device 5 on the aforesaid studs L when inserted in said bores 13.

Pivoted between the aforesaid ears 11, as by pivot pins 14 and extending laterally in front of the squeegee blade is a paint or ink distributor 15 which deposits and distributes the paint of ink on the printing screen S in the frame F. This distributor 15 comprises a ledge and scraper forming bar-like member that is specifically shown as an angle-bar having flanges or sides of unequal length for forming a trough T. In actual practice, a flat bar pivotally mounted on the pins 14 along one edge adequately serves the purpose. This bar member 15 is gravity actuated and has suflicient weight to swing sharply between its positions to expedite and accelerate the flow of the paint or ink which is rather thick and slow-flowing.

The bar member 15 swings on its pivots 14 between a substantially horizonal position to form a ledge or trough T, as shown in Figure 4, during the return stroke of the squeegee device 5 on the chains B. As the bar member 15 is disposed immediately in front of the squeegee blade 6, the paint or ink that accumulates on the front of the squeegee blade 6 drains down the inverted blade 6 and collects on the ledge or trough T formed by the bar 15.

When the squeegee device 5 moves around the end of the conveyor B to start the printing stroke, the bar mem ber 15 gravitates to a substantially vertical or pendent position, as shown in Figure 3, so that the paint or ink collected thereon is dropped onto the screen S in front of the squeegee blade 6 immediately at the beginning of the printing stroke. In order that all of the paint or ink collected on the ledge or trough T will be discharged at the proper location on the printing screen S at the beginning of the printing stroke, the bar member 15 is of sufficient weight or is weighted to cause it to swing sharply due to gravity to drop or dump the paint or ink. In addition, the bar 15 is of such width that its free edge Y will strike the frame F and screen S to thereby jar the paint or ink from the bar onto the screen.

In pendent or substantially vertical position the bar 15 acts as a distributor during the printing stroke, the free edge Y sliding over the printing screen S and pushing and distributing the paint or ink over and along the screen S in front of the squeegee blade 6. During this distributing operation, the bar 15 leaves a thin layer of paint or ink spread over the screen S in advance of the squeegee blade 6 to be pressed by said blade through the screen in the usual manner.

Excess paint or ink is pushed onto an upwardly curved guard G at the rear end of the frame F and is elevated thereby until the bar 15 gravitates on the pivot pins 14 back to ledge or trough forming position. in order to limitswinging of the bar 15 to horizontal position, its free edge Y abuts the flange 10 of the front plate 7 when inverted but the bar is free to swing in the opposite direction to its operative, discharging and distributing position when reverted.

In cases where the ink distributor is to be disposed in inactive position relative to, the squeegee blade, it is locked against swinging action by a clip 24), as shown in Figure 5 connected thereto by a screw'zl with its outer end bearing on the flange 10 of the front plate '7 and, although'the aforesaid elements are herein employed to lock'the distributor or ink trough in inoperative position relative to the squeegee blade, it is within the purview of this invention to substitute other conventional locking means for the same.

With this invention fully set forth, it is manifest that means are provided whereby the operation of the squeegees of screen process printing machines produce highly efficient results and, through the particular assemblage of elements set forth, or their equivalents, the cost ofproduction thereof is sufiiciently reasonable to warrant substitution of the same for the conventional squeegees.

Having thus described my invention, what i claim and desire to protect by Letters Patent is:

I the'squeegee and engaging the outer edge of the short side of the trough for securing the aforesaid trough in elevated' position relative to theworking edge of the blade. 2. A squeegee device for screen process printing machines having conveyor means for reciprocating a squeegee to convey the squeegee in a downwardly extending position over a screen to spread ink over the screen during the operative stroke and tilt the squeegee to extend upwardly during the return stroke, said device comprising a support adapted for'mounting on the conveyor of a screen process printing machine, a squeegee mounted on said support to bereciprocated 'by the conveyor, and a combination distributing and collecting'member pivotally mounted on said support in front of said squeegee and swingable by gravity between a substantially horizontal position in'engagement with the front of said squeegee to receive and collect ink that flows down the squeegee when the latter is tilted upwardly during the return stroke and a pendent position substantially in contact with the screen to drop the ink in front of the squeegee immediately at the beginning of the operative stroke and dis tribute the paint over the process screen during the operative stroke to leave a thin substantially uniform layer References Cited in the file of this patent UNITED STATES PATENTS 1,901,473 Respess Mar. 14, 1933 1,966,416 'Parmele et a1 July 10, 1934 2,421,210 Louft May 27, 1947