US1386896A - Appucationf - Google Patents

Description

C. F. PETERSON. PROCESS AND APPARATUS FOR THE MANUFACTURE OF SHEETS BY AGGREGATION 0F FLAKE MATERIALS. APPLICATION FILED SEPT-20, 1911.

,386,896. Patented Aug. 9, 1921.

2 SHEETS--SHEET l ventor'i E Charles EPeterso His fitter-neg.

C. F. PETERSON.

PROCESS AND APPARATUS FOR THE MANUFACTURE OF SHEET-S BY AGGREGATION 0F FLAKE MATERIALS.

APPLICATION FILED SEPT-20, 1911.

NS IIIIIII/I/III/I/IA Patented Aug. 9, 1921.

2 SHEETS-SHE'ET 2.

I nx/encof;

Charles F Peterson,

His flttornsg.

PATENT OFFICE.

UNITED STATES CHARLES F. PETERSON, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELEC- TRIC COMPANY, A CORPORATION OF NEW YORK. I

PROCESS AND AIIARATUS FOR THE MANUFACTURE OF SHEETS BY AGGREGATION 0E FLAKE MATERIALS.

To all whom it may concern:

Be it known that I, CHARLES F. PETERSON, a citizen of the United States, residin at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Processes and Apparatus for the Manufacture of Sheets by Aggregation of Flake Materials, of which the following is a specification.

My invention relates to the manufacture of sheets by the aggregation of flake material, and it is especially valuable for the production of relatively large mica sheets suitable for insulating electrical apparatus. It is my aim to expedite and cheapen the manufacture; to make practicable the use of inexpensive grades of material; and at the same time to render the product more uniform in thickness and density, and of superior quality generally.

My novel process of manufacture is most advantageously carried on by means of certain automatic apparatus or machinery which I have devised. Machines for making thick, rigid sheets or plates of aggregated mica splittings or flake mica (the terms flake and splitting are generally used interchangeably) have heretofore been used to some extent; but, so far as I am aware no machine hitherto used has been adapted for the production of flexible mica sheets, sheets, that is, of such thinness as about 20 mils or less, so that they can readily be flexed without injury. On the contrary, such sheets have always been made by slow, laborious hand methods of sticking or pasting the splittings together, one by one. And whereas, moreover, only the more expensive large splittings have been employed in hand pasting,because of the rapidly mounting labor cost when the size of the splittings diminishes,my invention enables the smaller and cheaper grades of splittings to be used quite as advantageously as the larger grades.

The impracticability of dealing with the smaller splittings by hand-and of dealing with any splittings by machinery-has been due not only to the obvious diiiiculties of properly placing and pasting the great number of irregularly shaped splittings, but also to the tendency of the unpasted splittings to cling together in such a way as to render Specification of Letters Patent.

Patented Aug. 9, 1921.

Application filed September 20, 1917. Serial No. 192,387.

the final product irregular in thickness and non-homogeneous in structure. This clinging tendency is due to the character of the splittings themselves, which are elementary mica flakes with surfaces so perfectly plain and smooth that whenever they are pressed together sufliciently to expel the air from between them (as necessarily happens in any pile of them), the contact between them is so perfect that air does not readily get in to enable them to separate against the atmospheric pressure on their outer sides. On account of this tendency of the splittings or flakes to cleave together, skilled'hand labor has been necessary to detect adhesions and effect separation, so that each component of a pasted sheet should be one single flake and not two or more; and so the labor of dealing with the smaller flakes has been absolutely prohibitive of their commercial use.

My invention affords, in the first place, an easy way of effecting separation of even the finest flakes. It also afi'ords a novel way of expeditiously assembling unpasted flakes in proper arrangement for forming a uniform, homogeneous layer and subsequently applying adhesive or binder to paste or stick them together wholesale, so to speak, instead of one by one as in handwork. This feature of the invention is applicable to large and small commercial flakes indiscriminately. F or the sake of securing the utmost uniformity and homogeneity of the final product, I find it best to make the raw pasted layer produced as above indicated thinner than commercial purposes usually require, and to produce therefrom a final raw sheet or plate of suitable thick ness by manifolding. This final raw sheet or plate is ultimately to be subjected to a heat and pressure treatment, in accordance with the usual practice with hand made raw sheets.

Other features of my invention will appear from the description hereinafter of the best ways and apparatus for carrying it out at present known to me, and its scope will be indicated in my claims. In the description, I have referred especially to the application of my invention to mica, since this is the most important, difficult, and elaborate application known to me.

In the accompanying drawings, Figure 1 is a diagrammatic sectional view of a-na-pparatus that may be used for assembling mica flakes in sheet form.

Fig. 2 is an elevation of a machine for producing raw pasted sheets, suitable for subsequent treatment, certain parts being in section, and Fig. 3 is a plan view, also with certain parts broken away or in section.

Fig. 4: is an enlarged cross-section of one of the parts shown in Figs. 2 and 3.

Figs. 5, 6, 7 8 and 9 are enlarged fragmentary views illustrating the construction and operation of certain parts of the mechanism shown in Figs. 2 and 3.

Fig. 10 is a view similar to Fig. 2 showing one end of a modified. form of machine, certain parts being broken away or omitted.

Fig. 11 shows a vertical longitudinal sec: tion of a part of the machine, with a portion broken out and omitted to save space on the drawing; Fig. 12 is a fragmentary plan view; and Fig. 13 shows an enlarged crosssection, at a plane corresponding to the line 1313 in Fig. 11. w

I will first describe the assembling of flakes in sheet form in the simplest manner.

The apparatus of Fig. 1 comprises a foraminous screen 11 at opposite sides of which a difference in pressure can be created. This screen may be of woven wire (of 10 mil. size) with openings about 5%" square. As shown, the screen 11 is secured over the mouth of an expanded nozzle or hood 12 with externally beveled edges 13, and the difference in pressure is created by suction through a conduit 14: connected to an exhaust fan or other suction means. Beneath the nozzle 12 is a box or casing 15 with a flaring edge or lip portion 16. In the box 15 is shown a mass of flakes 17. This box or container 15 may eonvenientl'y be referred to as the assembling chamber, since the assembling of the flakes into a layer or sheet takes place in it, and the screen 11 may for a similar reason be identified as the assembling screen. I

Now if the walls of the chamber 15 were removed and the space above the pile of flakes 17 left open to the atmosphere, the flakes would remain practically undisturbed,

no matter how strong the suction in the conduit 1 1. If the distance between the screen 11 and the flakes 17 were diminished, a point would eventually be reached where some of the flakes would be drawn up against the screen; and a like result might be attained by making the nozzle opening more nearly of the same size as the conduit 14, so as to render the suction through the screen greater. It would be found, however, that neither one of the measures (norany combination of them) would give an even, homogeneous, commercially useful layer of flakes; on the contrary, the layer would always be uneven or heterogeneous, lumpy in some places and very thin in others, to such an extent as to be useless forany practical purpose. It is for this reason that attempts to make sheet mica with a suction or differential pressure screen have hitherto failed.

lVith'the apparatus shown, however, a different result is possible. Supposing that the area of the nozzle opening 12 be about ten times the cross section of the conduit 1% (the presence of the screen 11 being disregarded in the computation), and that the minimum area of the tapering intake or nozzle 18 between the edges 13 and 16 approximate the erosssectional area of the conduit 1 1, then it will be observed that the mica flakes 17 are put in lively agitation. Not only this, but their tendency to cling together in bunches (as previously explained) is overcome, so that the individualv flakesseparate and fly, swirl, or soar in the free space of the assembling chamber 15, up toward the screen 11. In a very short interval, however, this agitated swirling of the flakes ceases, and the screen 11 is found to be completely covered with a fairly even, homogeneous layer of flakes. It is now possible to remove the con tainer 15; invert the nozzle 12 (assuming the conduit 1% to be flexible or the like) sprinkle or spray adhesive liquid (such as'sticky varnish) over the flakes to paste or stick them together; shut off the suction; detach the screen 11; and remove the layer of stuck together flakes and treat them, just about as though they hadbeen hand-pasted in the usual way.

The more important conditions affecting the successful production of a uniform layer of mica as just described are few and simple:

First, there is a difference in pressure at opposite sides of the screen 11, in virtue of which the flakes are drawn and held against it. This pressure difference is obviously greatest at the end of the swirling phenomenon, when the flow of air through the screen 11 is very nearly cut off by the fully formed mica layer. The effect of'this diminished flow through the screen is two-fold; it allows the partial vacuum in the assembling chamber15 to deteriorate; and it permits thepartial vacuum above the screen 11 to improve.

Second, there is a stream or current of air (or a multiplicity of such streams) sucked or drawn in through the intake 18 with sufiicient velocity to carry the flakes in suspen sion. This air stream (owing to the angle of the intakev nozzle 18) sweeps over the bottom of the chamber 15 so as to pick or take up the flakes lying there and carry them along dispersed in it. The streams initial direction is, however, of less importance than its velocity, for the flakes can be introduced into the chamber 15 in a great variety of ways that favor their being carried along dispersed in the stream, as by continually lid or periodically feeding them in through the air intake 18 itself. The air stream is swift and strong at the beginning of the whirling phenomenon, when the partial vacuum or suction in the assembling chamber is greatest, but falls off as the partial vacuum fails with the building up of the mica layer.

Third, there is in the assembling chamber a substantial free space in proximity to the screen 11. This not only gives opportunity for separation of adhering flakes from one another by thorough agitation or tumbling in the swirling air current, but also permits a circulation of the flakes hither and thither beneath the forming layer, so as to come within the influence of the suction through the various holes therein and cover them, This makes the process of building up the layer automatic and self-regulating, since the greatest suction and air flow is at the biggest holes.

. The more important features of a suction type of apparatus which affect the realization of these conditions are, evidently, the

free space in proximity to the assembling screen; the confining or inclosure of the assembling chamber to such an extent that the suction can create in it a partial vacuum of less intensity than that at the suction side of the screen, but considerable in comparison with the pressure of the surrounding atmos phere; the regulation of the inflow of air in such wise that it shall have sufficient velocity to carry the flakes in suspension; and the direction of the air current or stream with due regard to the mode of introduction of the flakes, so that they may be carried along dispersed in the stream. Yet however well the apparatus of Fig. 1 may combine all these features, it is necessarily subject to two serious practical limitations:

First, operation is necessarily interrupted when the screen 11 is covered, so that continuous or automatic provisions for feeding in the flakes are of little advantage.

Elecond, the air stream ultimately fails or becomes too weak to carry the flakes, and this usually occurs while the mica layer still presents small holes or other leaks that ought to be covered, and would be covered if only the flakes could be kept in agitation. little longer. I have found that it is practicable to remove both of these limitations by making the assembling screen travel into and out of the assembling chamber, so as continually to present fresh openings; which will give rise to an uninterrupted, vigorous stream of air for carrying and agitating the flakes. l have also found that this can be done without sacrifice of any of the con ditions important to successfulassembling. Such continuity of operation, however, makes desirable greater refinement in the introduction and separation of the flakes, that the supply shall always bear a properrelation to the capacity of the screen for taking them up, and so that the separation of adherent flakes shall always be thoroughly effected before the flakes reach the screen. The travel of the assembling screen, moreover, makes it possible to efl'ect the pasting of the assembled layer pcm' passe with its formation. I will now describe an apparatus of this sort which is completely automatic in its continuous performance of these functions, and which also performs other functions, such as the manifolding of the pasted mica layer, etc.

in the apparatus of Figs. 2 and 3, tie traveling assembling screen 21 is in the form of a continuous belt carried by rotating horizontal cylinders or drums 22 and 23 suitably journaled in the machine frame 24:. For reasons that will hereinafter appear, these drums 22 and 28 are of skeleton or openwork construction, consisting of solid end disks and thin, flat metal bars or rods 25 secured to them so as to lie in radial planes with their outer cages forming cylin der elements. )nly the drum 22 drives, and it receives its motion from a sprocket chain 26 itself c riven from a shaft 27 which is, in

turn, driven (through si'iitable worm gear ing) by an electric motor Assemhling of flakes on the screen 21 takes place at the drum 22; and though in this machine it is limited to the lower quadrant of the screens contact with the drum, yet for r asons of dra'tt control the whole drum is inclosed in a substantially air-tight casing 29 which the screen enters and leaves through narrow openings. The drum revolves clockwise, so that the upper portion of the screen belt 2 is the slack sine, and moves toward the right. The arrangeiue of the drums 22 and 23 is such that this slack upper portion of the belt 2 parts from the upper side of the 2 substantially horizontal; as

drum shown, the drums are of equal size, and so the taut driving lower portion of th 21 is horizontal too. The helt 21 may he of woven wire with ,1, openings, and may have a linear speed of some l5 per minute.

As already indicated. the assembling of lakes into a layer t kes place on the screen 21 while it is pass around the drum To this end, the int rior of the drum 22 is connected to the suction of an exhausterlll by means of a pipe 3 T he space 32 within the casing 29 beneath and to the left of the drum 2 constitutes the assembling chamber, being cut off from the rest of the space around the drum 22 by partition means in cluding spring-actuated rollers 33 and 34 which press firmly against the screen belt 21. Air admitted through an intake 35 is directed downward upon the flakes fed in at the bottom of said chamber 32 so as to swirl and take them up and carry them e belt along dispersed in the air stream to the screen 21. The arrangement of the intake 35 and the chamber walls combines with the suction conditions to direct the swirling flake-laden air stream upward to the right, so as to Strike first the fresh, uncovered por tion of the screen 21 as it enters the assembling chamber 32 past the roller 33 and deposit the larger flakes thereon. The air stream is deflected upward to the left toward the roller 3%, so that the swirl of leftover flakes continues in contact with the layer initially formed on the screen 21 during a substantial part of the screens travel, giving opportunity for any small openings in the initial. layer to be properly covered. All unattached flakes supplied fall to the bottom of the chamber 32 and are carried off as presently to be described. It will be observed that the portion of the screen 21 exposed in the assembling chamber 32 overhangs the chamber, so that flakes cannot settle and remain on it by gravity action and so spoil the uniformity of the original suction-formed layer.

I will now describe the separation of the flakes and the manner of uniformly feeding them to the assembling chamber 32.

At the extreme left of the machine is an apparatus comprising a horizontal drum 40 mounted to revolve between stationary end pieces 4:1 and 4-2, with felt or other suitable packing rings 43, 43 fitting in grooves in the end frames 44:, 4.4 of the drum4cO to prevent excessive leakage of air. The shaft 45 on which the drum 40 is mounted (by means of spokes 46, 4.6) is journa-led in the ends 41, 4:2, and is driven from the shaft 27 (above mentioned) by means of a sprocket chain 47 and a long shaft 48 connected to said shaft 27 by bevel gearing. The speed of the drum 40 may be some 30 revolutions per minute. of the drum 40 are mounted some six or more longitudinal paddles 50, and near one end of the drum is a transverse bulkhead 51 with a central opening 52 having a flaring mouth directed toward the left. Flake material can be introduced into the drum 40 from time to time by dumping it into a hopper 53 that opens through the end wall 41; a hinged lid 54 on this hopper prevents excessive inflow of air therethrough. From the chamber 55 formed at the right-hand end of the drum 40 by the bulkhead 51 there is a discharge through an opening 56 in the end wall 42; and above this discharge opening 56 there is a downward sloping air intake 57. In the discharge passage beyond the opening 56 suction. is created in a manner to be presently described.

When the drum L0 is revolving the flake material therein is continually tumbled about and agitated, being repeatedly carried up on the paddles 50 until it slides off and At the periphery falls to the bottom again. Owing to the suction at'the discharge 56 and the leakage through the charging hopper 53, there is a current or stream of air through the center of the drum that becomes fairly swift at the flaring opening 52, so as to be more than capable of carrying the flakes in suspension. is the material is thus agitated in this air current, the elementary flakes separate more or less completely. Individual elementaryv flakes are so light as to be readily suspended y the opening 52; aggregates of two or more elementary flakes that failof separation are so heavy in proportion to their exposed surface that they fail to become suspended by the current. Owing to the fairly rapid revolution of the drum, individual elementary flakes not captured during one tumble are not likely to form new adhesions before their next tumble: as a practical matter, it is found that adhering flakes are very rap idly and completely separated in the drum apparatus. The flakes that enter the chamber 55 are immediately caught in the swift downward current of air from the intake 57 and swept out through the discharge 56; any that escape capture in this way in the first instance are tumbled into the current again just as in the main portion of the drum.

it will be evident that the rate of discharge of flake material from the receiving and separating device 40 is likely to be quite irregular, varying with the quantity of flake the air current and carried out through material in the device and the flow of air I therethrough. In order that this irregularity may not be reflected in the layer built up in the assembling chamber 32, I interpose in the tortuous passage from the separating device L0 to the assembling chamber at 32 devices which regulate and equalize the introduction of i ake material into the assembling chamber.

The first of these regulating devices is a small foraminous revolving drum 60 mounted against the end wall 42, just above the discharge opening 56 from the device 40. This drum is driven from the shaft of the assembling drum 22 through a couple of sprocket chains 61 and 62, and may make some 8 or 10 revolutions per minute, clockwise. The lower wall of the discharge pas foraminous revolving drum 66 mounted in an angle at the bottom of the pass 63, with a n nnnum or clearance "beneath it and to the right. This drum 66 is driven through sprocket chains 6land 67, and may make some revolutions per minute cloc rwise,- thus having a surface speed about equal to that of the drum 60. The action of this drum 66 to regulate and equalize the flow of is very much like that of the drum 60. (During to its position and the possibility of its becoming choked, it is desirable to have a stream of air from intake 68 to strip and lift and swirl the flakes from this drum 66 rather than to rely on suction alone. A den 6 toward the rear of the drum 66 serves to prevent flakes from traveling on down behind the drum.

ibovo the drum 66 is a space 70 in which is exposed an auxiliary traveling screen '71 whereon the flakes are gathered by suction very much as on the main assembling screen 21. This screen 71 is in the form of a continuors traveling belt carried by rotating h al cylinders or drums t 2 and 73. The

a xiliar y assembling drum "'2 is of openwork :eleton construction similar to that of the main assembling drum 22, and its interior 1S c rested to the exhauster by means of a pr; 1 that opens into the pipe 2-31. i he drain which is smaller, is closed air-tight in order that no gathering may take place shields Z5, '75 are mountedadjaorder to constitute a barrierbeust spaces and 32 and to conhering to the drum 72 as far as The drum '7 drives the belt 71 a linear velocity greater than that of -belt 21. being itself driven clockthe sprocket chain 61. The layer of on the belt 71 is carried up on it, and 1'11 L in assembling chamber 32, and ti '0 there str pped off by the partl acuainand the stream of air from the int U. it spring-actuated. roller 76 ex- 1 1 A a 3. .cl es tne flake-laden air iiom the portion above the belt 71 where the flakes mlghl settle and remain by mere gravity and so spoil the uniforn'iity of distribution of flakes to the main assembling chamber The upper shieldv coacts with a damper roller 77, on the one hand, and with the drum 73 and a spring-actuated roller 78, on the other hand, to exclude the suction in the drum 7 2 from the portion of the belt 71 whence the flakes are to be picked up in the chamber 32, which facilitates the pick-up; and the roller 78 also serves to prevent air and flake leakage from the chamber 70 into the chamber. 32. The linear speed of the auxiliary belt 71 is sufficiently in excess of that of the main belt 21 to insure that the supply of flakes to the main assembling chamber 32 shall always exceed the capacity of the main belt 21 to take them; this insures an ample supply from which to produce a more uniform, homogeneous layer. The excess of flakes fall back on the belt 71 and are by it returned to the chamber 70, where they gravitate into the air stream from the intake 68. In case the excess of flakes about the drum 66 be sufficient to choke the passage of air therethrough, all inflow of flakes from the left will be stopped until the choking conditions are removed.

Mica dust and small flakes that pass through the screens 21 and 71 go to the exhauster 30. Obviously the treatment to which the flakes are subjected on their Way from the separating device 10 to the main assembling chamber 32 tends to insure separation of any elementary flakes that may cling together when they leave the device 40.

Referring now to the mica layer formed on the main assembling screen 21 as previously described. After passing the damper roller 8d, this layer continues its upward movement (being still under the influence of the suction within the drum 22) until the portion of the screen 21 carrying it becomes horizontal and passes out of the casing 29 between damper rollers 81 and 82, the former spring-actuated. Its upper side is then exposed to the atmosphere; but its lower side is over a chamber 83 in which a partial vacuum is maintained througha pi e connection 81 to thesuction pipe 31 of te blower 30. Here the screen 21 and the mica layer pass between paste distributing rollers 85 and 86, of which the former is spring actuated and the latter provided with a suitably drained drip trough 87. Adhesive fluid (such as'sticky varnish of a specific gravity of about .90 to .95) is applied to the upper surface of the mica layer by the roller 85, on which the fluid drips from an inclined metal sheet 88 whose upper edge rests against and scrapes a roller 89 that revolves in a bath 90 of the liquid, be ng driven counter-clockwise from the shaft 27 through belts 91 and 92, so as to make some 12 revolutions per minute. The adhesive accumulates in front of theroller 85 and is drawn between the flakes by capillary attraction and the suction beneath the layer. The

flakes are pressed and stuck together by the rollers and 86, which revolve by friction with the layer.

From the rollers 85 and 86, the pasted layer passes on to the right and over a couple of small rolls 93, 93, located just beyond the point of tangency of the screen 21 with its supporting drum 23 and driven clockwise from the shaft 27 through the sprocket chain 94 and a train of gears 95. After being relieved of the pasted layer, the screen 21. passes around the drum 23 and back to'the drum 22 through a cleaning device 98 comprising a tank of cleaning fluid that will dissolve the adhesive used (such as acetone or benzol), a presser roller 99, and a revolving brush 100 driven clockwise from the shaft 27 through a sprocket chain 101. The cleansed screen is guided into its narrow opening in the casing 29 by a pair of rollers 102,102.

The pasted mica layer is received or unloaded from the screen 21 (with the aid of the rolls 93, 93) by a multiplicity of parallel, horizontal traveling wire bands 104, and by them conveyed on to the right. These con'veyer bands 104 run in grooves in horizontal rolls 105and 106 suitably journaled in the machine frame, andtheir upper por tions (which carry the pasted layer) receive intermediate support from rolls 107, 108, and 109. The left-hand roll 105 drives the bands, andfis itself driven clockwise by the sprocket chain 94 above. mentioned,-the gearing 95 being driven from the shaft of this roll. "The rolls 98, 93 and 105 are hollow, and anti-adhesive fluid (such as acetone or be'ny'ol) is supplied them through hollow aXes 111,,111"and'112, and oozes out to theirsirrfaces through a multitude of fine perforations (too fine to'be visible on the drawing). To the right of the roll 108 and below the upper portions of the bands 104 is journaled a transverse hollow shaft 114 to which are attached a multiplicity of par.

allel hollow arm's 115, shown in a horizontal position to the right of said shaft. These arms 115 are spaced midway between the bands 104, so that they can be swung up and over to the left 'of the shaft 114 by means of, a gear 116 on said shaft and a toothed segment 117 pivoted on the machine frame and provided with an operating crank arm 118. r i

In the operation of the machine, the pasted mica layer is allowed to progress to the right until itsv edge reaches the free ends of the arms115; then if a product is desired of greater thickness than a single layer will yield, the motion of the'screen 2 1 and the bands 104 (and certain other parts) is arrested while the set of arms 115 is operatedas just described so as to fold the layer back on itself against therollers- 108 and '107 and thus manifold it. Each movement of the hollow shaft 114 to raise the. arms 1 15 almost instantly opens a valve 119 which controls a supply of anti-adhesive fluid (such as acetone or benzol) from pipe 120 to the hollow shaft and arms. The fluid exudes or oozes to the surfaces of the arms 115 through a multiplicity of very fine holes, and saturates contact surfaces or coverings of absorbent material with which they are provided, as in the form of stockings 1'21loo's'ely drawn over them (see Fig. 4). Then the screen 21 and bands 104 are put in motion again until the folded edge of the two-ply layer or sheet reaches the free ends of the arms 115, when another ply may be added in the same way,the operation being repeated as often as necessary. After the last manifolding, the sheet passes on to 'the right beyond. the arms1 15, when the single layer, behind it is torn off by the movement of the arms 115 for the first manifold'ing of a new sheet; and at the same paper or other material to which the sticky 7 sheets will not adhere on top of the pile 123 from time to time, so as to separate the successive pasted sheets and keep them from sticking to one another. f

It now remains only to describe the mechanical drive or actuation of various operating parts or agencies of the machine.

\V'he'n the'machine is inoperation, the 'SXllfllTStGl 30 is constantly driven in any suitable way, and the motor 28 and the shaft 27 are constantly running;-so, also, is the drum 40', which is connected to the rear end o'fthe shaft 27 as already described. The various moving, parts concerned in forming, pasting, and conveyingthe mica layer are all driven, as al'readydescribed, from sprockets and a pulley at the front end of the shaft 27. These sprockets and the pulley are not, however, mounted directly on the shaft 27, but on asleeve normally connected to the shaft by a toothed clutch whose movable member 131 can be moved out of mesh, against the resistance of a spring 132, by. a rocker arm'133 whose forked upperend engages in a groove in said member 181. It is by actuationofthis clutch 131 that the various parts are stopped when the mica layer is to be manifolded as already described. While the actuation of this clutch 131 and the operation of the arms 115 and .125 may be effected manually by an attendant, I have also provided for doing it automatically. 7

A longitudinalshaft 135'is driven by the cross shaft 27 through bevel gearing, and it, in turn, drives a cross shaft 136 through bevel gearing and another cross shaft 137 through Worm gearing 138. Keyed fast to the cross shaft 136 is a clutch member 140, and longitudinally shiftable along it are cooperating clutch members 1 11 and 142 which are normally held out of engagement as presently to be described, but are urged into engagement by springs. The clutch member 142 drives a sleeve 1 13 carrying a bevel gear 1 1 4- and a crank 1 15, and the crank 11 -5 is connected by a rod 1416 to the crank arm 118 which operates the layer folding arms 115. The clutch member 111 drives a. sleeve 117 which through hevel gearing; drives a longitudinal shaft 148 which through other bevel gearing drives a cross shaft 149, which carries a crank arm 150 connected to operate the piling or stacking 21171118 125 just as the folding arms operated. The parts are so proportioned that one complete revolution of the sleeves and 14:7 causes the arms 115 and to saving through about 180 and return, and the provisions for controlling their clutch members 1-11 and 1 12 are such that when thrown into engagement with the member 110 they make one complete revolution with it and ar, then automatically thrown out. The hevel gear 1 1% meshes with a corresponding gear on a short longitudinal shaft 151 which, through intermediate gearing 1:39 15 1, drives another longitudinal shaft 155 on which is a cam 156 which actuates the rocker arm 133 for throwing the clutch 131 in and out. This cam 158 makes one complete revolution whenever the sleeve 1&3 makes one, and 10llS the clutch 131 out practically from lseginning to end of that revolution, so that the moving; parts concerned in tori hing. pasting, and conveying the mica layers are arrested during that perioch i. 6., during eachswing,- of the arms 115. p

new remains only to describe the control ofthe c utch members 1&1 and 142.

The constantly running cross shaft 134' carries a longitudinaliv shiitah e cam 160 which is shai' t urged toward the ear end 01. the by a spring 181. The sh also a gear 162 which,through change moiinted on a stud 165 carried by a arm itself pivoted on said 137,-orives a gear on short cross shatt 16?. This shaft 1 carries a'cou of chain wheels 168 and 169 whose p811} cries are suitably notched to enable them to drive chain helts 1'70. and 111 which run over other freely running wheels 11 These chair belts 14'0, and171 have various cam pieces 174 175, etc, adjustahly mounted on teem. in passing ar and the wheels 168 and these 0. n pieces 174; and 175 engage and actuat levers 176 and177 which control the clutches 1453 and 1 11 respectively (see 6, and

The lever 17? controls the cam 1 11 directly,

while the lever 176 controls the cam 1412 through the medium 01 the cam 160 and the lever 178.

Referring, first, to the lever 1'76, it will be seen from Figs. 5 and 6 that this lever normally rests (by gravity) in a groove 1'79 in the cam 160, and thus keeps the cam in the position shown in Figs. 3 and G, where its clutch portion 181 (Fig. 6) is out of engagement with the clutch element 182 on the shatt 137, so that the cam remains stationary. ll hen, however, the cam piece 171 on the chain belt 1'70 strikes a beveled projection 183 at the end of the lever 1'76 (Fig. 6), itlitts the lever 176 out of said groove 179, and this allows the clutch 181., 182 to be thrown in by the spring 161 so as to cause the cam 160 to revolve. As the cam piece 174: trips past the projection 183, it allows the lever J6 to fall again; but the lever does not at once rest at the bottom of the cam groove 1'79, but on a larger portion 18% of the cam periphery. Here it remains until by its lateral engagement with an undividec crown portion 185 of the cam 160 said cam is tor-cedliack against the spring 161: this at nce throws out the clutch 181, 182 and allows th lever 1'76 to fall to the bottom of the groove 179, and thus the cam 160 makes one complete revolution and then comes to rest in its initial position.

As the cam 1.60 revolves, its beveled procting portion 186 strikes a beveled pro- 87 on the lever 1'78 (see Fig. '7) and "ms depresses the other end of said lever -.-;ainst he action of spring 188 and withwe a stud 189 thereon from its socket 190 in the periphery of the clutch 1 11. This allows said clutcn meml l i to be thr: vvn into en agement with l clutth men Jer 110 and thus he started 01111 1011. its theclutch member 1 12 v, ie stud 189 on the lever 1T8. rides on an enlarged portion 191 of the clutch hut for about half a revolution thereof, till the cam portion 186 is ection 18?. The stud 189 then drops on,

well past he lever 3;-

into a depression therein where it rides until it strikes the hovel 1512 at the entrance to its socket 190; h its engagement with this bevel t forces the clutch member 142 to the l M 8} and throws out the clutch. the stud 189 reaches he hottom 0;? the socket 190. a lQBVQlUl. stud 193 on the end of a spring-elevated latch lever 19% drops into a fhaped groove in the clutch member nd helps to bring it to rest without it in just the right positioni. 0.. in its initial position.

The control of the clutch member 1 11 by the lever 17; (seel ig. 9) is exactly similar to the action of the lever 178 on the clutch member 1 12 and so need not be described in 0502561250. The spring-actuated latch lever corresponding to the lever 19% is not shown in Fig. 9, to avoid confusion, but appears in Fig. 3.

The apparatus shown in Fig. 10 differs from that of Figs. 2 and 3 principally as regards the unloadingof the pasted mica layer from the traveling screen 221 and the passage of the flakes to the assembling chamber 232from the revolving drum 2&0. As shown, there is aset of traveling bands 200 superposet. on the screen 221 and passing around rolls or drums 201 and 202. The upper portions of the conveyer bands 20% lie in the same plane with these bands 200 and pass around a roll or drum 205 located between'the roll 201 and the roll 223 on which the screen 221 runs free. Thus the mica layer is transferred from the screen 221 to the conveyer bands 20% without any slight shock or stress such as may arise at the rclls 93. 03 of Figs. 2 and 3.

The drum 2&0 is shown as at a much lower level than the rest of the machine; it may, in fact, be beneath the floor on which the rest of the machine stands. The passage for the flakes there-fore extends upward without any downward pass. In. it is a foraminous revolving drum or roll 200.

that corresponos in its'action to the drum ($0 of Figs. and 3; an air intake 202 helps in the stripping of the flakes from the far side of this drum. There is also a foraminous revolving drum 271 that corresponds to the auxiliary traveling screen '71 of Figs. 2 and Spring-actuated valve rollers 276 and 27S bear on the exterior of this drum 271; and within it is a partiti 285 and a couple of spring-actuated valve rollers 28? and 289. Excess flake material fed 'to the assembling chamber232 has a chance to slide back by gravity clear to the drum 240.

In Figs. 11, 12, and 13 is shown a form of manifolding arm 315 whose contact surface is considerably reduced as compared with that of the arms 115 of Figs. 2, 3 and 4. The arm structure proper is practically unchanged; but a little above the upper surface of the arm a wire 316 ]S stretched taut, intermediate supports 317 and 318 being provided for it. The stocking 321 that forms the absorbent contact surface is put on over the wire 316 and is saturated by the anti-adhesive exuding from the arm 8l5.-the wick action of the fabric aiding.

hat I claim as new and desire to secure by Letters Patent of the United tates, is,-

1. The process of assembling .lte 1 aterial into sheets of uniform density, which consists in f eding flake material in a graduated stream into aconfined space, simultaneously creating in said space a swirling air current. of such velocity as to suspend and swirl the flake material sufficiently to efiect impingement of the particles thereof against each other and against the walls of the confined space and produce an elementary sepathrough a screen whereby the flake material is evenly distributed thereon.

2. The process of assembling flake material in sheet form which consists in creating a partial vacuum at one side of a foram-inous screen with a confined space at its other side; causing a swirling stream of air, of sufficient velocity to carry the flakes in suspension, to be sucked into said confined space from the surrounding atmosphere; and uniformly supplying flake material to said confined space to be carried along dispersed-in said swirling stream of air and automatically distributed over the screen in a uniform layer.

The method of carrying out the process set forth in claim 2 which consists in causin g the foraminous screen to travel and thus continually present free openings, so that the process shall be continuous and that there shall be an uninterrupted, vigorous swirling stream of air for carrying and agitating the flakes.

The method of carrying out the process set forth in claims 2 and 3 which consists in causing the air stream with its burden of flakes to: strike first the freshportion of the traveling screen, so as to deposit the larger flakes first, and in allowing the swirl. of left-over flakes to remain in contact with the screen and the initially formed layer for a substantial period of the screens travehso as to promote the covering of'small openings in said layer.

The method of carrying out the process set forth in claims 2 and 3 which consists in supplying flake material in quantities in excess of What can be taken by the screen and removing such excess.

6. The method of carrying out the process set forth in claims 2, 3, and 5 Which consists in obstructing the path of the air stream to the traveling screen so as to cause any BX treme excess of flake material to accumulate in such wise as to block the air flow and reduce the velocity and carrying ability of the air stream in front of the accumulation, and so check further accumulation, and gradually redelivering the material to the air stream at the far side of the accumula tion.

7. The method of carrying out the process set forth in claims 2 and 3 which consists 8. The process of aggregating flake material to commercial thickness in sheet or.

plate form which consists in forming a layer of flakes stuck together with adhesive and manifolding as many such layers as necessary to secure the desired thickness.

9. The process of aggregating flake material to commercial thickness in sheet or plate form which consists in assembling the flakes in sheet form as set forth in claim 2, supplying adhesive thereupon to stick the flakes together, and manifolding as many such layers of stuck together flakes as necessary to secure the desired thickness.

10. An apparatus for assembling flake material in sheet form, comprising a foraminous screen; means for creating a difference in air pressure between the opposite sides thereof; means forming at the high pressure side a confined assembling chamber adapted to receive the flake material and affording a substantial free air spacein proximity to the screen; and means for introducing into said chamber a swirling stream of air of sufficient velocity to carry the flake material in suspension, suitably directed to take up the flakes and allow. them to collect against the screen in a uniform layer under the influence of the aforesaid difference in air pressure.

11. An apparatus for I assembling flake material in sheet form, comprising a foraminous screen; means for creating a suction at one side thereof; means forming at the other side thereof a confined assembling chamber adapted to receive the flake material and affording a substantial free air space in proximity to the screen; and air intake means for the inflow from the surrounding atmosphere into said chamber, as a result of the suction aforesaid, of a stream of air of sufficient velocity to carry the flake material in suspension, suitably directed to swirl and take up the flakes and allowthem to be sucked against the screen in a uniform layer.

12. An apparatus for assembling flake material in sheet form, comprising a foraminous screen, means for creating a swirling stream of air in a confined space on one side of said screen and for aspirating said air therethrough, and means for uniformly supplying flake material to said swirling stream of air comprising a secondforaminous screen having provision for causing it to travel through said confined space, and means for aspirating a flake-laden stream of air through said second foraminous screen in advance of its entrance into said confined space.

13. An apparatus as set forth in claims 11 and 12, in combination with means for regulating and equalizing the introduction of flake material into the assembling chamber comprising a supply passage opening thereinto at one end and receiving flake material at the other; one or more secondary traveling assembling screens in said passage with corresponding suction creating means for collecting the flakes in a temporary layer; and corresponding air intake means for directing air streams upon the flake material on said screens to lift and carry it along to said chamber. I

14. An apparatus for assembling flake material in sheet form, comprising a traveling foraminous screen; means for creating a suction at one side thereof; means forming at the other side thereof a confined assembling chamber adapted to receive the flake material and affording a substantial free air space in proximity to the screen; and means for introducing flake material into said as sembling chamber and for also introducing a swirling stream of air to carry the flakes and allow them to be sucked against the screen in a uniform layer; the portion of the screen exposed to the flake-laden air in the chamber being so far from horizontal that flakes cannot settle and remain on it by gravity. i

15. An apparatus for assembling flake material in sheet form, comprising a horizontal openwork rotating cylinder; a travel ing foraminous screen belt on said cylinder which parts from its upper side substantially horizontal; means forming a confined assembling chamber inclosing a portion of the belt and the cylinder and affording a substantial free air space in proximity to the belt; means for creating a suction within the cylinder; means for introducing flake material into said assembling chamber, and for also introducing a stream of air to carry the flakes and allow them to be sucked against the belt in a uniform layer; and means cooperating with the upward-moving layer and the chamber wall to exclude the flake-laden air from the portion of said layer whose slope is such that additional flakes could settle and remain on it by gravity.

16. The method of separating mica flakes which consists in agitating r tumbling the flakes in a swirling air current of suflicient velocity to carry them in suspension.

17. An apparatus for separating and feeding flake material comprising a horizontal revolving drum with longitudinal baffle means at its periphery; discharge means opening from the center of said drum at one end and means for creating a suction therein; air intake means opening into said. drum adjacent said discharge; and means at the other end of said drumfor the introduction of flake material thereinto.

18. An apparatus for separating and feeding flake material comprising a horizontal revolving drum with longitudinal loaflie means at its periphery; a transverse bulkhead with a central opening therein forming a chamber at one end of said. drum discharge means opening from the center of said drum at the end adjacent said bulkhead and. means for creating a suction therein; air intake means opening into said chamber adjacent said discharge; and means at the other end of said drum for the introduction of flake material thereinto.

19. An apparatus for aggregating flake material in sheet form comprising a traveling belt which is substantially horizontal for a part of its travel; means cooperating with said belt, in an ascendant part of its path, .to assemble flake material thereon in a uniform layer; means for supplying adhesive upon the layer of flake material while in the aforesaid horizontal part of the belts travel a multiplicity of parallel, horizontally traveling bands receiving or unlo'ading'the adhesive-supplied layer from the foraminous, belt and a multiplicity of parallel arms pivoted beneath said bands and arranged to swing upward between them to fold the layer back on itself and thus manifold it.'

20. An apparatus for aggregating flake material in sheet form comprising a traveling foramin'ous screen belt which is substantially horizontal for a part of its travel and departs from the horizontal in an ascendant part thereof; flake-assembling devices cooperating with the belt during the last-mentioned part of its. travel, said devices including means forming at the side of the belt which comes uppermost when the belt subsequently becomes horizontal a confined assembling chamber which affords a substantial free air space in proximity to the belt, means for creating a suction at the opthe be'l't'in a uniform layer, the portion .of'

the beltexposed to the flake-laden being so far from horizontal that flakes cannot settle and remain on it by mere gravity;

means for supplying adhesive upon the I layer of flake material while in the aforesaid horizontal part'of the belts travel; a multiplicity of parallel, horizontally traveling bands receiving or unloading the adhesive-supplied layer from the belt; means for cleansing the unloaded belt on its way back to the flake-assembling means; and a multiplicity of parallel arms pivoted beneath said bands and arranged to swing upward between them to fold the layer back on itself and thus manifold it.

21. A device for handling sticky'sheets of flakes heldtogetherwith adhesive, comprising a member' with a contact surface of absorbent materialand means for supplying anti-adhesive to said absorbent material.

22. A device for handling sticky sheets of flakes held together with adhesive, comprising, a hollow member adapted to contain anti-adhesive fluid and having a inultiplicity of fine holes through its wall, and a covering of absorbent material on said member forming its contact surface and adapted to be saturated with anti-adhesive oozing out through said holes.

In witness whereof I, have hereunto set my hand this 19th day of September, 1917.

CHARLES F. PETERSON.

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