US3263272A

US3263272A - Film casting apparatus

Info

Publication number: US3263272A
Application number: US234918A
Authority: US
Inventors: Alvin M Marks; Mortimer M Marks
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-12-15
Filing date: 1962-11-02
Publication date: 1966-08-02
Anticipated expiration: 1983-08-02

Description

Aug. 2, 1966 A. M. MARKS ETAL FILM CASTING APPARATUS 5 Sheets-Sheet 1 Original Filed Dec.

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INVENTORS z44 V/A/ M M14846 5 Mae/M52 fl/ waif/(5 1966 A. M. MARKS ETAL FILM CASTING APPARATUS 5 Sheets-Sheet 2 Original Filed Dec.

FIG. 2

INVENTOR5 /4z M MAEKS Mae/74758 M M42185 BY @MXW A. M. MARKS ETAL FILM CASTING APPARATUS Aug. 2, 1966 5 Sheets-Sheet 5 Original Filed Dec. 15.

INVENTORS 41 l// M 44 42/65 Moef/wfe M 444/645 United States Patent 3,263,272 FILM CASTING APPARATUS Alvin M. Marks, 149-61 Powells Cove Blvd, and Mortimer M. Marks, 166-25 Cryders Lane, both of Whitestone, NY.

Original application Dec. 15, 1958, Ser. No. 780,580. Divided and this application Nov. 2, I962, Ser. No. 234,918

Claims priority, application France, Dec. 16, 1957, 753,953, Patent 1,188,708 7 Claims. (Cl. 18-15) The present invention is a division of applicants prior application for patent entitled, Film Casting Apparatus and Method, filed December 15, 1958, Serial No. 780,- 580, now abandoned, concerned with various apparatus for the manufacture of polarizing forms and products such as polarizing sheets or polarized glass or plastic lenses.

The present invention is also concerned with an apparatus for the casting of a continuous film from a solution, characterized by the fact that as the said solution is cast onto the casting surface, its flow is induced first in a horizontal motion, then in a vertical motion, thereafter in a second horizontal motion, and lastly, in a vertical motion, these consecutive motions thus causing the material cast onto the film to spread uniformly.

According to another embodiment of the invention, the casting surface is impelled to travel horizontally and then vertically, in such a manner that every point of this surface is displaced at the same speed, which results in a uniform spreading of the solution.

According to another embodiment of the invention, the casting surface consists of a continuous strip forming a ribbon.

According to another embodiment of the invention, the solution used is such that it may be subjected to linear tension when it is partly dry so as to obtain stretched sheets once the solution has partially solidified.

The invention is also concerned with a machine which enables the foregoing process, or any similar process to be accomplished, and which is characterized by a band on which the solution is caused to flow, thus constituting the casting surface, and which travels first horizontally, then vertically, then again horizontally and lastly vertically, following a quadrilateral form, such as that of a square or a quadrangle, as it passes over inclined bars in such a way as to enable the said strip or web to travel freely and continuously.

According to another embodiment, the bars are four in number, and are inclined in such a manner as to cause their longitudinal axes to converge two by two, thus allowing the strip or web to travel in the successively changing directions.

The angle of inclination of the bars is judiciously set at 45 degrees in its relation to the horizontal position so as to permit a 90 degree change of direction for the casting strip or web, thus facilitating the horizontal movement, then the vertical movement of the said strip or web.

According to another embodiment, the means by which the casting strip or web is driven consist in rollers, made of rubber for example, placed at the back of the casting strip or web, which operate in conjunction with small rollers, also made of rubber for example, placed on the Patented August 2, 1966 front of the casting strip or web and pressing against the latter in such a manner that the said strip or web is gripped between the rollers at the back and the small rollers pressing down on the front and is thus driven by friction.

According to another embodiment, the solution to be applied to the cast-ing strip or web is applied to the latter by means of a nozzle facing the casting strip or web and situated at its upper edge so as to enable the said solution to spread by gravity.

According to another embodiment, a scraping device, consisting for example of a wiper, is placed at the lower edge of the casting strip, in a location corresponding to its first horizontal course and at a certain horizontal distance from the nozzle, in such a manner as to remove any excess solution which may accumulate at this lower edge of the casting strip owing to the gravity flow of said solution.

The invention is also concerned with a machine for the production, continuously, starting with a solution, of a sheet which crystallizes by tension, and the application in a continuous manner of said sheet on a support, coated with an adhesive, and the subsequent rolling of said product on a second support, coated with an adhesive, which latter adhesive contains a stabilizing chemical agent, thus producing, with a single machine, a continuous, endless and simultaneously stabilized rolled polarizing sheet.

Machines and devices according to the invention are represented as examples, but are not limited thereto, in the drawings attached hereto, among which:

FIGURE 1 is a schematic view of the complete embodiment of a machine for the production of a film, and is particularly adapted to the production of plane lightpolarizing film.

FIGURE 2 is a diagram describing the operation of the machine designed to produce the film.

FIGURE 3 is a perspective view, giving a complete illustration of the machine designed for the production of film by casting a solution onto a casting strip.

FIGURE 4 is a perspective view, showing the installation and the means by which the film is removed from the casting strip on the one hand, and how it is continuously fixed to a support, on the other.

In FIGURES 1, 2, and 3, the continuous casting strip 1 is a ribbon made of flexible material. This ribbon has a constant width and its two lateral edges are parallel.

In order to obtain the best conditions possible for the realization of the process in the present invention, it was indispensable to provide a large, flat surface that could travel continuously and in different directions.

The casting web it operates in conjunction with the inclined bars 2 so as to unfold continuously.

As it can be seen in FIGURES 2 and 3, the casting web 1 folds over a first time, forming an open loop as it passes over the first bar. Due to the angle of inclination of the longitudinal axis of each of the bars 2, which is appropriately set at 45 degrees, the casting web 1, after traveling in the vertical direction F changes its course of direction to F which is horizontal and perpendicular to its first, vertical direction.

The inclined bars being four in number, and the described process of travel over the first bar being repeated in the case of the other three, the casting web is thus caused to travel on a course such as that described by a square.

Thus, using as a reference basis the right side of FIG- URE 2, a first displacement of the casting web is obtained, vertically and downward (see arrow F then a horizontal displacement from right to left (see arrow F after passing over the first inclined bar; then a second vertical displacement is obtained in the upward direction as shown by the arrow F after passing over a second inclined bar, and, lastly, a second horizontal displacement from left to right in the direction indicated by the arrow F after passing over a third bar. In this way the casting web 1 resumes its traveling course all over again by starting anew in the direction of the arrow F after passing over the fourth incline-d bar.

The bars 2 are attached to the rear wall of the machine 3 by means of supporting small brackets 4.

The casting web 1 glides over the bars 2, which latter are firmly mounted in hollow supports 5, which are in one piece with brackets 4. The bars 2 do not revolve.

The casting Web 1 is able to pass over the inclined bars 2 and change its direction with a minimum of friction thanks to a correct choice of materials for the casting web as well as the bars. For example, a polyester film, produced by condensation of triphthalic acid and ethylene glycol, is used for the casting web, and aluminum for the bars.

If a change of position is desired of the casting web on the bars, the web may be moved axially along the bars by imparting a rotational movement to the latter.

The machine comprises a means of driving the casting web forward. This driving mechanism consists in a system of rollers 6 and 7, made of rubber for example, which are located at the back of the casting web.

These rollers are placed longitudinally opposite each other on one same horizontal axis, and are so positioned as to permit them to drive the casting web in the two areas where it travels vertically.

,Rollers 6 and 7 operate in conjunction with the compressing small rollers 8, made of rubber for example, which are placed on the front of the casting web on its two lateral sides.

As one can see, the edges of the casting web 1 are thus caused to pass between the rollers 6 and 7 and the small rollers 8. The casting web is gripped between these two rotating surfaces and thus is caused to be driven forward.

The description which follows relates more particularly to the mechanical details which provide the driving motion and to the method of support of rollers 6 and 7 and the small rollers 8.

9 illustrates a support consisting of a steel plate, for example, placed in a horizontal position and fastened to a vertical upright 10, which in turn forms an integral part with the

frame parts

11 and 12, which latter are one with the structure of the machine.

In the center of plate 9, a bevel pinion 13 is mounted, which a driving motor revolves, as explained below.

' 14 and 15 show bevel pinions that are enmeshed in pinion 13 so as to change the rotating motion by 90 degrees. These pinions are placed on either side of the driving pinion 13, which sets rollers 6 and 7 in motion in opposite directions. Thus, we obtain a displacement of the casting web 1 in a downward vertical direction on the one hand, and in an upward vertical direction on the other.

17 illustrates the supporting blocks for the shaft 16 between the

bevel pinions

14 and 15 and the rollers 6 and 7, and 18 illustrates the coupling sleeves.

19 shows the support in which the other end of the rollers 6 and 7 turn, which end is situated next to lateral walls 20 20 of the frame of the machine.

Furthermore, the supports for the small rollers 8 are resilient so as to permit a pressure more or less great on the casting web. These supports comprise a part 21, mounted for rotational movement, either on an element 22, fixed to plate 9, or directly onto the support 19, according to whether the small roller concerned is situated i on the inner edge of the web or on the outer edge. A resilient part such as spring 23 enables one to obtain a varying pressure of the small rollers 8 onto the casting web.

The rotational movement is transmitted to the bevel pinion 13 from an electric motor 24, which motor transmits its rotational movement by means of chains 25 and 26. Chain 26 passes around pinions 27 and 28, which have different diameters. Transmission between wheel 28 and bevel pinion 13, may be obtained for example by means of a worm screw 31 acting upon a tangent wheel (see FIGURES 1 and 2).

In FIGURE 1, the motor 24 drives the transmission chains 25 and 26 by means of a speed control system 32 in order to obtain a slow but uniform rotation for the casting web 1, and further in order to be able to obtain varying speeds if desired to adapt the process for example to the casting of different materials, and under variable conditions of temperature, humidity, drying, etc.

In FIGURE 1, there is represented schematically shaft 33 of the tangent wheel 30 which revolves in two bearings 34 fixed to a supporting part 35, which latter is mounted on part 36 of the frame of the machine. There is also illustrated schematically that part of the frame 37 upon which bars 2 are mounted.

The casting mixture is delivered to the casting web from a feed tank 38, which can be seen in the upper corner of FIGURE 3. The contents from the tank 38 pour into a funnel 39, which latter is connected to a flexible tube 40. Tank 38 is enclosed in a sort of box 41, fastened to the upper lateral surface 20 of the frame; the casting mixture flows by gravity through the conduit 40 and is cast upon the casting web 1 by jet delivered from a nozzle 42.

As one can see, especially in FIGURES 3 and 6, the nozzle is mounted on a support 43, which can be moved on the one hand vertically so as to adjust the height of the point of impact of the solution onto the casting web, and on the other horizontally so as to adjust the distance between the nozzles end and the casing web 1, which distance is shown by B on FIGURE 6. For this purpose, support 43 is set at the end of a flexible bar 44, made of steel for example. This bar 44 is connected by part 45 to a vertical upright 46, which latter is fixed to plate 9. A screw 47 may come in contact with the blade 44 so as to give it a more or less inclined position as related to the vertical and in this way regulate the distance B between the nozzles mouth and the casting web 1. Screw 47 turns in a threaded hole driven in a support 48, connected to the other parts of the machine. A valve 43 controls the delivery from the nozzle.

The liquid mixture coming out of nozzle 42 reaches the casting web 1 on which it flows downward following a diagonal line 49.

The angle of inclination of line 49 as related to the vertical is dependent upon the speed at which the casting web moves and the speed at which the liquid mixture is ejected. Thus, the liquid mixture spreads on the entire surface of the casting web as the latter travels forward in its course.

Due to the fact that the casting web travels in four different directions, the flow of the liquid mixture is attracted toward varying inclinations, which are illustrated in FIGURE 3 by parallel lines traced on the casting web.

In FIGURE 2, more schematically, these varying inclinations are shown in a more simple way by groups of parallel lines, 50 and 51, respectively. This method thus affords a better spreading of the liquid mixture, which is more uniform and not subject to ridging which occurs when the drying takes place in a preferred direction. Along the upper horizontal course F and in the vertical course F the film is subjected to the action of heat ray, prior to its removal. During the downward vertical course F the film is dry enough to be removed from the web 1 and to be stretched in a manner explained hereinafter.

In FIGURE 3 and 4, the solution in the course of solidification has been schematically represented.

(a) Lines of varying thicknesses and curled, drawn in the upper right area onto the casting Web 1, represent heavy molecules in chain formation and irregular positions;

(b) Parallel lines, drawn on the film 68 during the stretching operation after removal from the casting web 1 represent the molecules in a regular position, which position will subsequently facilitate perfect crystallization.

Nevertheless, in order to avoid any harmful accumulation of liquid mixture on the lower edge 1 of the casting web, a device has been provided to scrap off all excess material. This scraping device which, for example, may consist of a wiping strip i shown as 54 in FIGURES 2 and 3.

Thus, the accumulation of sticky matter at the end of the rollers 6 and 7 and the small rollers 8 is avoided, eliminating the possibility of the casting web being slowed down in its course.

One very important advantage in using a casting web consisting of a continuous endless strip is the fact that during its travel in the different directions, the spreading liquid solution is subjected to the same speed of conveyance at all points. This allows for a uniform spreading of said solution on the web referred to, both crosswise and lengthwise alike.

Any excess of liquid which might anyhow remain on the casting web 1, drips from the edge of the web into a channel 55, appropriately positioned in the lower part of the machine, as is schematically represented in FIG- URE 2.

The liquid :passes from channel 55 into a tank 56 below, from which it is recovered for reuse after being passed through suitable filters not represented in the drawings.

The entire assembly of mechanisms described above is mounted in a frame, represented for general purposes as 57.

As it has already been stated, this frame consists of a horizontal part 12 and two lateral walls 20 and 20 We have already designated the rear wall of this frame as 3.

At the front of this frame there are two

steel bars

58 and 59 connecting the lateral Walls 20 and 20 Another steel plate 60 is fixed to the front top of the frame.

At the top of the frame, lamps 61 have been installed for the purpose of speeding up the drying process of the cast solution. These lamps are set in, in such a position as to throw their heat into the casting web as it travels along its second horizontal course.

A ventilation system for the evacuation of noxious vapors and the renewal of air has been installed in the upper part of the machine. This system comprises a suction vent 62 of an elongated form, in which there are holes 63 through which holes the said vapors to be evacuated pass.

The suction vent is in an inclined position, somewhat parallel to the axis of bar 2 over which passes the casting web.

Suction vent 62 evacuates the noxious vapors through a duct 63 with an outlet on the outside of the machine.

There is shown on the left side of FIGURE 3 as system of protection for the casting web, consisting of transparent plastic sheets. These sheets 64, which are held in frame 65 so as to constitute rigid panels, are mounted on the entire face of the machine and thus assure protection of the solution cast on web 1 from the dust that is suspended in the air. Indeed, it is very important to prevent the dust from depositing on the casting web, because it could be very harmful to the optical properties of the polarizing film obtained from the cast liquid solution.

Now We shall describe in the following expos the method by which the film of solid solution is removed from the casting web and deposited in a continuous manner on a supporting strip.

Located in the area where the web is traveling along its second vertical course, cutters have been provided, suitably spaced, and set near the inner and outer edges of the casting web.

According to the embodiment represented in FIG- URES l to 4, the cutters and the supporting strip on which the cast film is to be fixed are grouped in a frame generally referred to as 67. This frame is perpendicular to structure 57, which is the frame of the casting machine.

Cutters 66 are subjected to the action of counterweights 26 so that they come down gently onto the casting web. By moving the counterweights 26 one adjusts the pressure of the cutters on the web and on the film. In this way, a strip of film 68 is cut out with a

waste

69 and 69 on either side corresponding to that part of the edges lying between the blade of the cutter and the inner and outer edge ends of the casting web. This waste winds on a shaft 70 provided for the purpose, which is located quite near the cutters.

The following description relates particularly to the production of a film capable of producing a plane polarized light.

In order to transform the film 68 into a plane polarizer, a process of removal applies, which is already known, and according to which the film is removed from the support on which it has been cast and subsequently deposited on a supporting strip while undergoing a linear stretching which results in drawing the molecules of the polarizing material in the same direction. This is accomplished by giving to the supporting strip a speed much greater than the average speed of the casting web.

In FIGURES l and 4, 71 is the bobbin for the supporting strip 72, which is driven by a friction drum 7l1 This supporting strip travels the following course:

First, it passes over the rollers 75 and 75 and enters into a chamber 73 provided with a moistenin-g means such as roller 74 which enables its coating with a substance favoring its adherence to the film 6 8. The supporting strip is put in contact with the roller 74 by the roller 74 which roller 74 is impregnated with the coat ing liquid supplied from the container 73-, through the connection 73 This method is applied only in the case where the final product consists of a polarizing film attached to the flexible support of the film. In this case no adhesive is used inasmuch as the films flexible support is only used for temporary purposes, the support being discarded after the polarizing film has been transferred to a. permanent support such as a glass plate.

The supporting strip 72 then passes over roller 75 then over another roller 76, mounted at the end of pivoting arms 77. The function of these arms will be explained below. Between the rollers 7'5 and 76, there is mounted a protective plate 72 which covers the supporting strip.

Strip 72 then passes over other rollers 78 and 79 and rises vertically inside the frame 67 in order to reach the drying devices shown on the left side of FIGURE 1.

In FIGURE 1, we see the course followed by the supporting strip 72 with the film fixed on it.

After having risen vertically inside the frame 67, strip 72 and film 68 follow a horizontal course after passing over roller 80. The strip and the film then emerge from the frame through the aperture 67 and pass through the film casting machine at the opening 82 which has been made in the wall of the frame.

Strip 72 and film 68 are then directed to a heated enclosure 83, and inside this enclosure the evaporation of all excess solvent is completed; the linear molecules of the film are forced to line up parallel to one another clue to the elimination of the solvent. Thereupon, the forces due to crystallization dispose the molecules in a regular network pattern.

The strip and the film travel in the heated chamber 83, first in one direction, passing over rollers 84, and then in the opposite direction, passing over roller 85,

going through a sort of tunnel 83 formed by a double wall inside chamber 83.

After passing over roller 85, the supporting strip and the film are wound on drum 86 and form a bobbin 87. The drying air enters chamber 83 through a conduit 86 circulates cross-current in the direct-ion opposite that of strip 7268, and leaves the chamber through an exhaust 83 situated at its top.

Near the bobbin 87 is a peep-hole.

On FIGURE 1, the arrows F indicate the direction in which the cut off waste bands travel.

The arrow F indicates the direction in which the film removed from the casting web travels.

The arrow F shows the direction in which the supporting strip travels.

And lastly, the arrow F shows the course taken by the supporting strip 72 and the film 68.

As already mentioned above, drum 76 is mounted on a pivoting arms 77 which enables it to move in the directions shown by arrows P In this manner, by means of the screw X, the distance D, which separates the point at which the film 68 is secured to the casting web 1, is thus regulated. The angle at which the removal takes place is thus adjusted. This angle simultaneously controls the tension exerted on the film and the apportioning of said tension on the film and on the support 72, thus all-owing for the maximum tension and maximum orientation possible.

The supporting strip 72 and the film 68 are rotated by means of an independent group of motors 88, placed on top of frame 67.

A speed control system 89 is placed at the power outlet of the motor so as to be able to adjust at will the speed at which the supporting strip and the film are driven. Power from the motor is transmitted by means of

belts

90 and 91, for example, first to the roller 80. This roller then transmits the motion, as represented for example in FIGURE 1, by means of a chain 81 which passes over various pulleys mounted on the axes of the drums.

In the lower part of FIGURE 1, a means of rotating drum 86, starting from the roller 79, is schematically represented. This motion is obtained by means of

several belts

82, 83 and 84. A tension device 84 is placed in between.

There are, therefore, two groups of motors, independent of each other, the first one which serves to drive the casting web 1, and the second to drive first the supporting strip 72 and then the supporting strip 72 and the film 68 together. This allows for the different speeds that are necessary in order to obtain linear tension for the polarizing film 68.

These two groups of

motors

24 and 88 may be operated from a distance, at a controls desk by remote control. The operational parameters of these two groups are indicated to the operator by illuminated indicators and dials positioned at the control desk.

, According to the figures, therefore, and referring particularly to FIGURE 1, it is obvious that in order to carry out the process in conformance with the invention, there are definitively three groups of machines comprised in the installation. These three groups are the following:

The machinery with the casting web on which the film is cast, whose frame is identified under the general reference numeral 57;

j The machinery comprising the cutters and the supporting strip, identified under the general reference numeral 67;

i The heating chamber 83 and the means for winding the film produced on the spool 87.

Having thus fully described the invention, what is claimed as new and desired to be secured by Letters Patent of the United States is:

1.- A machine for continuously casting a foil comprising an endless flexible band, a' gravity flow fluid casting sta- &

tion on said band, a nozzle member directed at said casting station, a source of foil forming solution connected to said nozzle, a power source connected to said band for driving the same, guide means for guiding said band past said nozzle and an appreciable distance there'beyond in a generally vertical orientation and generally horizontal direction of travel and for subsequently guiding said band to travel in at least one direction of travel other than horizontal while maintaining said band in generally vertical orientation, and means adjacent said band and spaced from said gravity flow fluid casting station for removing formed foil from said band at a velocity which is constant across the width of said band.

2. A machine according to claim 1, wherein said means for removing foil from said band comprises a second band adjacent said first band and spaced from said flow station and a source of rotary power connected to said second band.

3. A machine according to claim 2, wherein said source of rotary power is effective to drive said second band at a speed exceeding the speed of said first-mentioned band.

4. A machine according to claim 1, further comprising heating means for partially drying said foil-forming solution on said band prior to operation of said means for removing foil from said band.

5. A machine for continuously casting a foil comprising an endless flexible band, a gravity flow fluid casting station on said band, guide means for supporting and directing said band in a generally vertical orientation in the region of said casting station, a nozzle member directed at said gravity flow station on said band, a source of foil forming solution connected to said nozzle, a power source connected to said band for driving said band an appreciable distance beyond said fluid casting station in a generally horizontal direction while maintaining the same in said generally vertical orientation, means for changing the direction of travel of said band to a generally vertical direction, means for supporting and directing said band in a generally vertical orientation during said generally vertical travel and means adjacent said band and spaced from said flow station for removing formed foil from said band at a velocity which is constant across the width of said band.

6. A machine for continuously casting a foil comprising an endless flexible band, a casting station on said band, a nozzle member directed at said casting station, a source of foil forming solution connected to said nozzle, a power source connected to said band for driving the same, guide means for guiding said band past said nozzle and for an appreciable distance there'beyond in a first horizontal direction, and subsequently thereto in a generally vertical direction, and subsequently thereto in a second substantially horizontal direction opposed to said first horizontal direction, said guide means being effective to maintain said band in generally vertical orientation during travel of said band in said first horizontal, vertical and second horizontal direction, and means adjacent said band and spaced from said casting station for removing formed foil from said band at a velocity which is constant across the width of said band.

7. A machine according to claim 6, wherein said guiding means comprises a first rod member having a length at least equal to the width of said band, said first rod member being mounted in fixed position in a vertical plane adjacent the plane occupied by said band during travel thereof in said first horizontal direction, said first rod member being mounted within said vertical plane at an angle of approximately to the horizontal, said first rod member being operative to guide said band from said first horizontal direction to said vertical direction, and a second rod member having a length at least equal to the width of said band, said second rod member being mounted in a fixed position in a vertical plane adjacent the plane occupied by said hand during travel thereof in said vertical direction, and within said vertical plane at an angle of approximately 45 to the horizontal, said second 9 10 rod member being operative to guide said band from said 2,408,377 10/ 1946 Dangelmajer 260 29.1 vertical direction to said second horizontal direction. 2,439,302 4/1948 Francis 18-15 2,468,975 5/1949 Held et a] 26029.1 References Cited by the Examiner 2,510,967 6/ 1950 Flanagan 18-45 TE 5 SChLlitZe UNITED STA S 2,546,326 3/1951 Jurgensen et a1 18-15 X 1,824,337 9/1931 Erchengrun 18-45 2,572,315 10/1951 Campbell 83-265 1,894,467 1/1933 Jacque 18-45 2,593,405 4/1952 Beckham 156--100 2,0 1,79 2 193 Pr nke X 2,756,459 7/1956 Kellner 18- 15 333,522 4/1937 Calvert 2 1 8- 2 10 3,051,054 8/1962 Crandon 8865 32 g f WILLIAM J. STEPHENSON, Primary Examiner. 2,308,949 6/1943 Alderfer 1815 DAVID H. RUBIN, J SPENCER OVERHOLSER, 2,367,111 1/1945 Fowler et a] 156-100 L. S. SQUIRES, Examiners.

Claims

1. A MACHINE FOR CONTINUOUSLY CASTING A FOIL COMPRISING AN ENDLESS FLEXIBLE BAND, A GRAVITY FLOW FLUID CASTING STATION ON SAID BAND, A NOZZLE MEMBER DIRECTED AT SAID CASTING STATION, A SOURCE OF FOIL FORMING SOLUTION CONNECTED TO SAID NOZZLE, A POWER SOURCE CONNECTED TO SAID BAND FOR DRIVING THE SAME, GUIDE MEANS FOR GUIDING SAID BAND PAST SAID NOZZLE AND AN APPRECIABLE DISTANCE THEREBEYOND IN A GENERALLY VERTICAL ORIENTATION AND GENERALLY HORIZONTAL DIREACTION OF TRAVEL AND FOR SUBSEQUENTLY GUIDING SAID BAND TO TRAVEL IN AT LEAST ONE DIRECTION OF TRAVEL OTHER THAN HORIZONTAL WHILE MAINTAINING SAID BAND IN GENERALLY VERTICAL ORIENTATION, AND MEANS ADJACENT SAID BAND AND SPACED FROM SAID GRAVITY FLOW FLUID CASTING STATION FOR REMOVING FORMED FOIL FROM SAID BAND AT A VELOCITY WHICH IS CONSTANT ACROSS THE WIDTH OF SAID BAND.