US2345202A - Portable projection apparatus - Google Patents

Description

March 28, 1944 R. H. LARSON 2,345,202 PORTABLE PROJECTION APPARATUS Filed Aug. 2, 1940 3 Sheets-Sheet 1 fiw m: x/geriiyarsom March 23, 1944. LARSON 2,345,202

PORTABLE PROJECTION APPARATUS Filed Aug. 2, 1940 3 Sheets-Sheet 2 March 28, 1944. R. H. LARSON 2,345,202

PORTABLE PROJECTION APPARATUS Filed Aug. 2, 1940 3Sheets-Sheet 5 Patented Mar. 28, 1944 PORTABLE PROJECTION APPARATUS Robert H. Larson,

Geneva,

111., assignor to Operadio Manufacturing 00., St. Charles, 111., a corporation oi Illinois Application August 2, 1940, Serial No. 349,943

- 9 Claims.

This invention relates to the combination of a picture projeector and a record playing mechanism for presenting a visual and audible message, such as a sales demonstration,'dramatic production or other material for the entertainment or instruction 01 a listener, and it is particularly concerned with the compact, portable arrangement of these elements.

One object of the invention is to provide a case for a portable picture projector having a detachable portion designed to stand alone in upright position to serve as a projection screen.

Another object is to provide a portable projector having a case and a detachable cover for the case arranged to serve as a projection screen, the cover including a part which will functionas a base to support the screen in upright position.

A further object is to provide a carrying case with a picture projector mounted fixedly therein in the position of use, so that when the case is set down and opened the projector may be placed in operation promptly with a minimum of adjustment.

It is also an object of the invention to provide a carrying case within which there is mounted a picture projector and also a driving motor having a spindle which projects through the top of the case to carry a removable turntable, together with a stylus arm pivoted to swing over the turntable, and a detachable cover having a top portion with a cavity to enclose the stylus arm and a side wall to enclose the turntable when removed and stored on edge in the case, so that the entire equipment may be compactly arranged for carriage.

It is likewise an object to provide a record player with electrical sound amplifying apparatus and a case by which the various elements are supported, the upper portion of the case carrying a turntable and its driving motor, a pick-up arm and a loud speaker unit, and the bottom wall of the case being completely detachable from the re mainder thereof and carrying the chassis oi the amplifier as a unit for convenience in servicing and repairing the same.

More specifically it is the object of the invention to provide a portable apparatus with a case i to stand upright on the desk or table surface, the necessary controls for the apparatus being located at one side of the assembly, and the sound projecting speaker element being disposed at the opposite side so that the operator may stand or sit opposite the auditor during the presentation.

Other objects and advantages will be apparent from the following description taken in conjunction with the drawings in which:

Figure 1 is a perspective view showing the projector and record player embodying this invention set up on a desk in the position of use, with the cover supporting a projection screen.

Figure 2 is a side elevation 01! the portable apparatus showing the projector located within the case and adjusted in the position of use, and showing a record disc on the turntable of the playing mechanism.

Figure 3 is a top plan view of the parts shown in Figure 2, with a portion of the turntable and record disc broken away.

Figure 4 is a vertical section taken substantially as indicated at line 4-4 on Figure 3, showing the location of the turntable motor and loud speaker'unit within the casing.

Figure 5 is a transverse sectional view 01 the cover as inverted to support a projection screen,

being taken substantially as a section as indi-' cated at line 5-5 on Figure 7, and showing a plurality of record discs stored in the cover.

Figure 6 is a plan view or the bottom wall andin carrying position, but with the cover of the case omitted.

Figure 9 is an end elevation showing the cover attached by its hinges and ready to be swung to closed position.

Figure 10 is a perspective view of the portable unit with the case closed and with a supplemental record carrying pocket attached thereto.

Figure 11 is a vertical detail section of a modified form of case and cover as arranged to carry riety of structures. Accordingly, it is the intention to cover all variations and alternative constructions falling within the spirit and scope of the invention as defined by the appended claims.

As illustrated in Figure l, the portable equipment embodying this invention is set up for oberation on a desk or table top A. In this view the case I stands at one corner of the supporting surface A, and the cover 2 of the case is shown removed and inverted with its top portion 8 as a base or standard, while its side wall 4, extending at .right angles from the portion 1, stands upright and provides a surface I which serves as a projection screen toward which the lens I of the projector is focused. A grille I in one side wall of the case I denotes the position of a loud speaker unit within the case, and a disc record 8 serves as the source of the sound which is transmitted to the speaker by way of an electrical pick-up device I, having a stylus II and carried by an arm ll pivoted to swing over the record 2 as the latter rotates.

Figures 2, 8 and 4 illustrate the mechanism on a larger scale and more in detail, showing the turntable I2 by which the record disc II is supported, and the spindle II on which the turntable itself is removably carried. The spindle is driven by a motor unit, as seen at If in Figure 4, which is suspended from the top wall I! of the case I and may include speed reducing gearing (not shown) between the electric motor and the spindle I3. The loud speaker unit It is seen in Figure 4, mounted on the inner face of the side wall which contains the grille I, and in Figure 2 the stylus arm II is shown connected to a supporting bracket I1 by a pivot at I! which engages the upper leg I! of the bracket, while its lower leg is bolted to the top wall of the case I substantially at the corner thereof which is farthest from the axis of the spindle II. The U- shaped formation of the bracket II, with its upright portion 2i rising from the top wall of the case, and its upper leg I! extending horizontally toward the turntable I2, but in a plane above that of the turntable surface, permits the use of an unusually large record disc, such as that indicated in dotted outline at 22 in Figures 1 and 2, because the marginal portion of the disc may travel under the arm I9 and under the pivot It by which the stylus arm II is attached to the bracket. This feature is the subject of a separate application Serial No. 349,948, filed on August 2, 1940, by Edward A. Ash and Robert H. Larson. From the pick-up unit 9 an electrical conductor 23 extends through the arm II and through clearance openings in the bracket II down into the case I for connection with the speaker and amplifier system.

The vertical wall of the case opposite that which contains the grille I, and supports the speaker unit I6, is only a partial wall 24 which extends in front of the motor unit I and connects with a horizontal bridge 25 on which the projector unit of the apparatus is fixed in a position for use when the case is set down in its normal position, resting upon the rubber feet 26 which are provided on its bottom wall 21. The projector includes the usual lamp housing 28 and film gate mechanism indicated at 29, together with a focusing tube 30 carrying the lens through which the light rays are projected for throwing an image on the screen at 5. The projector illustrated is intended to employ transparencies arranged in sequence on a strip of film substantially similar to that used for motion pictures. The

leading end of such a film is indicated in coiled formation at 3ibelow the film gate 29, and a reserve portion is shown coiled at 3| within a curved guard or retainer 32 above the fllm gate. It may be understood that the intermittent rotation of a control member, in the form of a knob 33, serves to advance the film for the successive projection of the views on the screen. A pushbutton switch 34, disposed below the bridge 25, controls the projector lamp in the housing 2! and connects it with a source of electric current supplied through a flexible cable 35 terminating in an attachment plug 38 of standard design. The fixed portion of the end wall 31 of the casing I terminates at one side of the extended position of the lens tube 30, and the opening thus formed permits the tube to be extended as shown in Figure 2 for focusing the image on the screen. When the projector is not in use, the tube 30 is telescopically retracted, and the opening in the end wall of the case is covered by a closure member 38 hinged at its lower edge at 39 for swinging down out of the way, as shown in Figure 2, when the projector is in use. A spring arm 40 engages the top wall of the case frictionally. to hold the part 38 closed when it is swung to upright position.

The panel in which the switch 24 is set includes a second push-button switch II which controls the operation of the motor I4 for driving the spindle l3, and also a switch member 02 which connects the amplifying apparatus in the circuit which operates the loud speaker I8. This switch member 42 may also operate a volume control when rotated more or less beyond starting position. These controls may be of any familiar type and need not be described in detail,

but it may be noted that the panel 43 which supports theswitch elements 34, II and I2 is set back from the plane of the wall 2 and the front flange of the bridge 25, so that the control rnembers do not project beyond this plane. The bottom wall 21, however, extends slightly forward of the plane of the wall 24, and its front flange 21 provides a trough to receive the edge of the turntable I2 when it is. removed from the spindle I3 ahd disposed vertically, as indicated in dotted outline on Figure 2, and as also shown in Figure 8. A clip 24 attached to the wall 24 overhangs the margin of the turntable in this position, and when the hinged member 38 is swung to closed position it fits against the periphery of the turntable I2, holding it definitely in place, and a flange 38 on the part 38 overlaps the turntable to retain it in this position.

When the turntable is thus removed the stylus Is may be relased from the pick-up unit 0 by means of a set screw 9" in the end of the unit, and the arm II is then anchored in an oblique position across the top wall of the case I by engagement of a flanged button 44 on the under side of the arm, with a notched clip 45 secured to the top wall of the case I. The clip member I! is sufficiently resilient to permit the button 44 to snap into the notch of the clip 45 and to be retained yieldingly thereby until the arm is again disengaged for active service.

When the turntable has been thus stowed against the side of the projector, and the stylus arm I I has been anchored above the top wall, the detachable cover 2 is applied so that the cavity of the portion 3 encloses the stylus arm II and the projecting spindle I3 at the top of the case, while the part 4 of the cover extends over the open side of the case for enclosing the turntable and other parts therein. A suitable cleat 44 is provided on the face of the wall 24 for winding the cable 35 in a compact hank, and a guard flange 41, upstanding from the wall adjacent the endof the case, confines the hank within proper limits so that the overlapping flange 4' of the cover shall not cut the cable. The flange 4" at the other end of the cover overlaps the edge of the closure member 38 to hold it securely shut when the cover has been applied.

Preferably, the cover is constructed, as shown in Figures and 9, with separable hinges, the hingepintles 48 being attached to th case I ad.- Jacent its top wall, and the hook-shaped portions 48 of the hinges being secured to the marginal flange of the top portion 3 of the cover. Thus when the cover is swung to open position it is readily disengageable by merely unhooking the parts 4! from the pintles 48, audit is just as simply replaced and then rotated to the closed position indicated in broken lines at4 on Figure 9. When the cover is thus closed the hookshaped portions 49 of the hinges are in upwardly open position so that they can carry their share of the weight of the case I when the outfit is lifted by means of the handle '50 secured in the cover; and the cover is held in closed position by means of fasteners 5| which may be of the swinging hasp type, commonly used on trunks, suitcases and other luggage. These fasteners are shown in Figure 2 attached to the end walls of the case, ready to engage the intermembering tongues 52 and studs 53 carried by the flanges 4 and 4 of the cover.

As seen in Figures 5 and 10, the handle 50 is secured in'a recess 54 formed in the cover part 2, and the handle is of flexible material, such as leather, so that when the cover is removed the handle may be collapsed to lie entirely within the recess ll; thus when the part 3 serves as a standard for the part 4, it can rest flatly upon the supportingsurface, such as the desk top A shown in Figure 1. If desired, the surface'of the part 2 may be fitted with rubber buttons 55 to avoid marring the supporting surface.

The projection screen i may be of any suitable sheet material of a proper tone or color,

" mounted on the inner face of the wall 4 of the cover, but Figure 5 shows a preferred arrangement in which a pad of paper sheets 5 is firmly secured by clamping screws 58 and a clamp bar 51 adjacent the lower margins of the sheets, while the upper margins are tucked under a lip Bl eX- tending along the upper edge of the cover wall V 4. This permits the top sheet 5 to be slipped from under the lip 58 and torn off along the edge of the bar 51, whenever it becomes soiled, thus immediately exposing a fresh sheet for use as a projection screen; if desired, sheets of various tints may be supplied to give a desired color tone to the projected image.

As shown in Figure 5, the cover also provides for the storage of one or more record discs, seen at 40 resting upon a channeled spring arm ll fastened in the cavity of the top portion 2. The opposite edges of the records are confined in a channel 82 which forms the marginal portion of the wall 4 remote from the top portion 3. To release the records 60 it is only necessary to press down upon the spring arm ll, allowing them to be tipped out of storage position for removal and use. When replaced in the cover they are held firmly therein and are fully enclosed when the cover is applied to the case I and swung into closed position. as already described.

Figure 11 shows a modified arrangement in which the bottom wall 21 of the case I extends slightly farther away from the plane of the wall 24 than in the form shown in Figure 3. The extra width provides for lodgment of records in the trough formed behind the marginal flange 21 of the bottom wall, and in this form the lower edge 4 of the cover wall 4 has no flange, but fits snugly within the flange 21 when the cover is applied. In this case the cover is not hinged but is lowered directly over the top wall of the case i so that the edge 4 can enter the space back of the flange 21 The cavity of the cover portion 3 which accommodates the stylus arm II when the cover is closed, includes some clear space, and this is taken advantage of as storage space for one or more extra fllm receptacles which are in the form of small, covered tin cans, two of which are 1 shown at 63 in Figure 7. As many as four such receptacles may be accommodated in the available space and will be held in place by an elastic tension member, such as the coil spring 64 connected to one of the side flanges of the cover portion 3 and extending obliquely therefrom to an anchorage at 65 on the cover wall 3 itself. Extra needles to replace the stylus lli may be stored in a receptacle 68 secured to the inner face of the closure member 38 and provided with a spring closed cover 61.

Th amplifying system interposed between the pick-up unit 9 and-the loud speaker l8 may be of any suitable circuit containing one or more stages of amplification, and may include the usual condenser elements and thermionic tubes of suitable characteristics. This apparatus is mounted as a unit on the bottom wail.21, as seen in Figure 6, most of the wiring which connects the various elements being omitted from this view for the sake of clearness. As seen in Figure 6, this bottom wall includes the marginal flange 21 extending on all four sides, and removable screws 68 extend through this flange for engagement with the-vertical walls of the case. Upon removal of the, screws 68 the entire upper portion of the case may be lifted away from the bottom wall 21, and upon disconnection of a few conductor wires from their terminals in the amplifier the latter, as assembled on the bottom wall 21, can be entirely separated from the rest of the case. As seen in Figure 6 a bent strip of sheet metal 10 is set on edge and secured, as by welding, to the bottom wall so as to form a support or chassis for the audion tubes 1| and 12 and the electrolytic filter condenser 13. Other elements of the panel 11 of insulating material attached to the wall 21. It will be noted that a portion of the metal strip 10 forms the vertical panel 43 by which the switch elements 34, 4| and 42 are carried, The supply cable 35 leads through an opening in the strip 10, and by way of connections not shown in Figure 6 the current is thus made available for testing the circuit when the I amplifier has been disconnected from the remainder of the outfit. Such disconnection merely involves detaching from the terminals on the panel 11 Fe wires which extend therefrom to the motor unit i4, the speaker Hi, the lamp in the projector housing 28, and the pick-up 9 on the arm H Fragmentary portions of these connecting wires are shown in Figure 6, extending from the terminals to which they are attached on the panel 11.

The portion 18 of the member 10 which supports the tubes II and I2 is set back from the plane of the panel portion 43, forming a forwardly open recess in which the tubes are exposed to view, seen in Figures 2 and 4. This makes it possible to remove and replace the tubes themselves without disassembling the case. Preferably, in the vicinity of th tubes the bottom wall has vent openings 21, and the open front of the recess provides for constant flow of air through this space to carry off the heat generated when the amplifier is in service. The case I is otherwise ventilated by means of louvres I in the side wall which includes the grid 1, and by ample clearance spaces above and around the motor unit M, as indicated at l. In addition, the lateral walls of the recess 54 are formed with vent openings 54 so that when the cover is applied immediately after the apparatus has been in use, the heat generated by the lampof the projector may be readily dissipated. While the projector is in use and a record disc is operating on the turntable 12, the disc is protected from the heat of the lamp by a metallic shield 19, preferably of aluminum, which is secured to the under side of the top wall in the case and extends vertically as a curtain over the upper portion of the lamp housing 28. thus requiring the heated air to spread out under the top wall l5 before it can escape upward toward the tumtable and record disc.

For many purposes a ten-inch record disc will carry all the material necessary for a given presentation, and discs of this size may be housed within the carrying case, either in the manner shown in Figure 5 or by means of the modified structure shown in Figure 11. For conveniently transporting a twelve-inch record, or even a sixteen-inch record, which is the maximum size operable on the turntable, a special pocket or portfolio. such as that shown at 80 in Figure 10, may be provided. By means of snap fasteners of the glove button type, projecting from the outer face of the cover portion 4, as seen at 8| in Figures 5. 7 and 9, and flexible straps 82, also provided with snap fasteners 83 to engage the end flanges of the cover portion 3, such a pocket may be quickly. but detachably, secured to the side of the cas so as to be carried conveniently with it.

Operation As an example of the use of the combined picture projector and record player and the special features of the carrying case for these units which are characteristic of this invention, it may be assumed that the outfit is to be employed by a salesman for demonstrating or explaining his product to a prospective customer or buyer. Arriving in the buyers oflice with the case I in closed condition, as shown in Figure 10, the salesman sets it down in its normal upright position on one corner of the buyers desk A in the position indicated in Figure 1. He releases the fasteners 5|. swings up the cover 3. 4, as indicated in Figure 9, and disengages the hook-shaped hinge members 49 so that he may then place the cover in inverted position at the other end of the desk top A, as seen in Figure 1. He then swings down the hinged closure 38, releasing the turntable and places it in its working position on the spindle l3: inserting a stylus needle in in the pick-up 9. he then takes a record disc either from the spring retainer 6i of the cover or from the auxiliary pocket 80, which he has previously detached from the cover, and arranges the disc on the turntable with the stylus in position. It is only necessary then to unwind the cable 35 from its cleat 46 and to plug it into any convenient outlet to supply current for the machine. Pressing the switch-button 34 turns on the lamp in the projeetormlisplaying the first picture of the series on the film and permitting it to be properly focused by telescopic adjustment of the lens tube 30. Pressing the button 4| starts the turntable motor, and turning the switch 42 energizes the amplifier system which is then quickly adjusted to the proper tone volume.

It will be evident that all these simple arrangements can be made rapidly and completed in the course of a few seconds since everything is in convenient reach of the salesman who is acting as the operator of the equipment, and who will naturally make a few introductory remarks while he is thus setting up the apparatus. From that point the demonstration proceeds by continuous operation of the record on the turntable, which provides a running discourse accompanying the series of pictures displayed on the screen 5 as the control knob 33 is turned at intervals by the operator. Preferably, the phonograph record may have embodied in it a simple bell tone or other audible signal at intervals to give the operator his cue for shifting the film to change the display from one picture to the next. During the presentation the salesman acting as operator sits at one side of the desk, as indicated at B, and the prospective customer remains in his normal position at the other side of the desk, as indicated at C. There is no chance of annoying or tiring the customer during the initial preparations, since the apparatus requires so little time to set up, and calls for no elaborate re-arrangement or adjustment of the customers office; and as the preparation proceeds, the sound is projected directly toward the customer by the loud speaker operating through the grille 1 while the screen 5 is conveniently visible to him without special effort. The knob 33 is the only control which requires manipulation by the salesman, and even this simple movement is hidden from the customer by the position of the case I so that it offers no distraction, and the customer's attention is easily held to the subject of the presentation. The equipment is thus ideal for sales and soliciting work, but, obviously, it is not limited to that field, and can be used in various ways for purposes of instruction or entertainment.

As illustrated in Figure 1 the projection apparatus is set up to project an image on the screen contained in the lid of the case and the projector is arranged for using strip film. 11, under certain circumstances, it is desirable to obtain a larger image than that which can be thrown on the screen 5, a suitable larger screen may be supported at a greater distance from the projector. Whether a small or a large screen is used, the projector may be arranged to accommodate strip film as illustrated, or to accommodate slides.

I claim as my invention:

1. A portable projection apparatus comprising, in combination, a picture projector, a carrying case in which it is fixedly and permanently mounted so as to be in readiness for operation when the case is opened, and a detachable cover for said case comprising a wall, a pad of superimposed sheets for use successively as projection screens, clamping means on the wall engaging a marginal portion of said pad and a lip extending from the wall engaging an opposite marginal portion of the pad, together with a part extending at right angles from one edge of said wall to record playing mechanism supported in the case including a spindle extending through the top wall thereof, and a turntable removably engaged with the spindle, said case having an opening opposite said lens of the projector with a hinged closure for said opening and having a space to accommodate the turntable in vertical position on edge when removed from the spindle, and said closure having a retaining flange which overlaps a marginal portion of the turntable, confining it when the closure is closed and releasing it when the closure is swung to open position.

3. In the combination defined in claim 2, a detachable cover for the case including a side wall and means for securing it in position to en close said space which accommodates the turntable, said side wall including a flange which overlaps said hinged closure to secure it in closed position.

4. In combination, a picture projector including a light directing lens, a carrying case in which it is mounted in position for use, a record playing mechanism supported in the case including a spindle extending through the top wall thereof, a turntable removably engaged with the spindle, a stylus arm pivotally mounted to swing over the top wall of the case, and a detachable cover including a portion having a cavity to enclose the stylus arm, and a wall extending at right angles to said portion providing a projection screen and fitting over one side of the case when the cover is applied thereto, said first mentioned portion of the cover acting as a standard to support the screen in upright position when the-cover is detached from the case and set up in inverted position. i

5. In combination, a picture projector, a carrying case in which it is mounted, and a detachable cover for said case comprising a wall providing a projection screen and a marginally flanged part extending at right angles thereto having a cavity open in the direction in which said wall extends, the outer surface of said part acting as a base to support the screen in upright position when the cover is detached from the case and provided with an elastic member stretched obliquely from the flange of said part to its base wall to act as a retaining strap for film containers.

6. In combination, a picture projector including a light directing lens and a picture control member, a carrying case in which the projector is mounted in position for use, a record playing mechanism supported by the case including an electric motor and a spindle extending through the top wall of the case, a turntable operable by the spindle, said case having an opening in one end opposite the lens of the projector, a sound amplifier including a speaker unit mounted in one side wall of the case, and a stylus arm mounted to swing over the turntable and having an operative connection with the sound amplifier, together with a conductor cable, a switch for the projector lamp, a switch for the turntable motor and a control switch for the sound amplifier, all presented at the side of the case opposite that which carries the speaker unit, and a removable cover which includes a portion to enclose the stylus arm and 9. depending portion which exposes said switches, said conductor cable and said projector control member when the cover is removed.

'7. In the combination defined in claim 6, the depending portion of said cover having a flat surface dimensioned to serve as a projection screen, and the portion which encloses the stylus arm having a substantially flat outer surface disposed at right angles to such projection screen and acting as a base to support the screen in upright position when the cover is removed and inverted.

8. In combination, a picture projector including, a light directing lens, a carrying case in 5 which the projector is fixedly mounted in position for use, a record playing mechanism supported in the case including a spindle extending through the top wall thereof, a turntable removably engageable with the spindle, a stylus arm pivotally attached to the top wall to swing over said turntable, and a cover including a portion having a downwardly open cavity to enclose the spindle and stylus arm with a wall depending from said portion to fit over one side of the case when the cover is applied. thereto, together with a carrying handle attached to the upper face of the cover portion having said cavity, said cover being attached to the case by separable hinges connecting the portion which has the cavity with the top of the case at the side opposite that covered by the depending portion, each'of said hinges comprising a part on the cover and a part on the case formed to suspend the case from the cover when the latter is in closed position, the portion of the hinge on the cover being separable from the other portion when the cover is inverted by rotation about the hinge axis.

9. In combination, a picture projector including a light directing lens and a control member, a carrying case in which the projector is secured in position for use, said case having an opening opposite said lens of the projector with a hinged closure for said opening, and a cover detachable from said case to expose one side of the projector and its control member, said cover including a wall providing a projection screen and a part extending at right angles thereto to act as a standard to support the screen in upright position when the cover is detached from the case, said side wall of the cover including a flange which overlaps said hinged closure to secure it in closed position when the cover is applied to the case.

ROBERT H. LARSON.

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