US2425255A - Photoelectric control for game devices - Google Patents

Description

Aug. 5, 1947. J. A. MacLAGAN ETAL PHOTOELECTRIC CONTROL FOR GAME DEVICES Filed Jime 25. 1942 m m 2 7 m Y 2 :2. B .8 101% @E. va T 01 Q W E {FLU Patented Aug. 5, 1947 PHOTOELECTRIC CONTROL FOR GAME DEVICES James A. MacLagan, Forest Park, and Thaddeus "A. Walsh, Chi

cago,.lll., assignors to Pioneer Trust & Savings Bank of Chicago, as trustee Application June 25, 1942, Serial No. 448,468

16 Claims.

The present invention relates generally to signalling devices and more particularly to foul detecting means for games and recreational contests such as bowling. Th present invention is an improvement in certain respects upon our automatic foul line keeper for which application for Letters Patent, Serial No. 389,976, filed April 23, 1941, has been made, referenceto same being made herein to the extent subject matter in common may be involved.

One of the objects of the present invention is to provide an improved circuit for photo-electric cells or the like which responds to slight interruptions or dimming of the beam as where smoke haze might exist and operate a fire alarm before heat developed is enough to set oif other well known detectors, or, as where the sole of the shoe on the foot of a player committing a foul interrupts only a portion of the beam.

A further object of the invention is to provide an improved detector of fouls at the foul line where the passage or presence of a bowling ball upon the foul line or a sudden fall in the voltage powering the circuit will not register a false foul.

Another object of the invention is to provide a set of interlocked circuits immediately responsive to interruption, one of wh ch prevents operation of the signal as long as it is interrupted and another of which prevents the operation of the signal before it is interrupted.

Another object of the invention is to provide a compact and simple unit of equipment which is inexpensive and can be readily installed upon a bowling alley and serviced easily from time to time, as required Another object of the invention is to provide a foul detector for bowling alleys characterized by a stream-lined arrangement of parts with those subject to damage located below the alley bed.

These being among the objects of the present invention, other and further objects will become apparent from the drawings, the description relating thereto and the appended claims.

Referring now to the drawings:

Fig. 1 is a vertical section taken longitudinally through a bowling alley indicating the arrangement and preferred construction of the interlocked devices that detect infractions of the rules of play;

Fig. 2 is a fragmentary view, a part of which is enlarged, taken from above the alley shown in Fig. 1;

Fig. 3 is a diagrammatical showing of the photo-electrical controls and their interlock employed to detect infractions of rules of play at the foul line.

Referring now to the drawings more specifically, the bowling alley indicated at l0 comprises a bed Ii divided by a foul line I! into a runway l3 upon one side and a varnished portion M upon the other side over which the ball i5 travels to reach and strike the bowling pins I6 that are set up on the far end of the alley Along both sides of the varnished portion, the alley I0 is bounded by gutters I1 and .the gutters by rails lB, each rail separating adjacent alleys one from another where more than one alley is installed.

At the ends of the rails l8 that are adjacent the foul line l2, the rails are cut away as at 20 to receive a box 2| in which are mounted in shielded relationship the light sources for the photo-electric beams and the two photo-electric cells and also, preferably, the circuits which are employed to detect infractions of rules of play at the foul line.

More particularly, in each box is provided a light source 22 for one of the alleys and the photoelectric receiver for the beam of light projected over'an adjacent alley, each box 2| being identical between alleys to serve 'as a source of light to project the beams to the adjacent photoelectric receiver over one alley on one side and to act as a receiver for the beams of light projected from another box over another alley on the other side.

Because of this arrangement, .the source of light for the beams and the photocells occupy a very small space in each'box and in the rest of the box there is room enough for all of the simplified photo-electric equipment provided by the present invention. Although it is possible to place the photo-electric control circuits elsewhere, if upon occasion such is deemed to be desirable, it is preferred that the photo-electric circuits be mounted in the box so that from a service and stray capacity viewpoint one box or unit can be removed in event of failure, repair or insertion of new tubes, and replaced by another unit ready to operate that need only be adjusted to its environment, which adjustment can be done with little trouble.

In such an installation, live rubber grommets are employed to secure the box in place at widely spaced points to eliminate vibration and provide stability. In fact, where the units are original equipment for the alley, a yoke separate from and disposed under the alley boards may be employed to link all the boxes together as an independent floating unit supported upon the under supports of the alley with extensive rubber cushions to absorb shock.

More particularly, for each alley two beams of light are arranged one above the other, the top one 23 being located where it is interrupted by a ball approaching the foul line before the lower beam 24 is interrupted, and is the last of the two beams to be re-established as the ball rolls beyond the foul line, it being impossible thereby to interrupt the lower team 24 with a bowling ball without interrupting the top beam 23 first.

The lower beam 24 is a wide beam with its greatest width disposed in a vertical plane as more particularly described in our application Serial No, 389,976, reference to which is hereby made.

Furthermore, if desired, a trip beam 25 "may be employed down the alley a short way to control a normally closed switch 26 that is held open by energization of the relay 53a to prevent registering an infraction as a foul unless the ball is released to pass down the alley. Interruptance of the beam 25 operates to close the switch 26 by means of a circuit similar to that controlled by beam 23.

Furthermore, another circuit similar to that controlled by the beam 23, which will be described later, may be controlled by a beam 21 located just in front of the pins I6 to open a normally open switch 28 held closed by energization of the relay 53b. The switch is permitted to open when a ball passes that point to prevent a player committing an intentional foul when he sees that the ball has struck the pins and left them in such a way as to provide the player with a diflicult second try. The photo- electric controls 25 and 21 and the operation of the switches 26 and 28 will be described further in their relation to the photo- electric controls 23 and 24, it being understood that the photo- electric controls 25 and 21 can be dispensed with in any installation if the results provided by them are not desired by the alley owner.

From light sources 22 the beams run substantially longitudinally of the alley to fall upon mirror 30 that direct the rays across the alley at the foul line I2 and against mirrors 3i on the other side of the alley which in turn direct the beams against other mirrors 32 and 33, respectively, and by the last mirrors the beams are directed downwardly against photo-electric cells, a photo-electric cell 34 being disposed in the path of one beam beneath an aperture 35 and a photoelectric cell 36 being disposed in the path of another beam beneath an aperture 31. The apertures are cut in the intermediate framework or shield 39 of the box 2|.

Condensing lenses 38 disposed in the path of the beams provide parallel rays of light in the beams where they cross the alley, and provide focal points for the beams at the photo-electric cells. Aside from the relative location of the photo-electric cells in the box along with their circuits, the construction is similar in many respects to that disclosed in our application Serial No. 389,976, reference to which is hereby made for further details to the extent that they might be of interest.

Referring now to Fig. 3, a gong and a foul signal lamp 4I are powered independently from an A. C. house line 49 through a step down transformer 43, if desired, which provides a voltage of from 6 to 32 volts as controlled by a switch (not shown) in the referee's booth, depending upon manufacturing expedients and the desires of alley owners. The lamp and gong, preferably a single stroke gong or chime, are connected in parallel with each other and with the switch 44 of a normally open relay 45 for automatic operation. The relay has a self-energizing circuit I01 connected to one of the contacts of the switch to energize the relay and the switch it controls and hold the switch closed once it is energized, until such time as a normally closed bi-metal timing switch 41 breaks after application of heat by a heater unit 48.

The relay 45 is powered from the current source 42, through the conductor I 00, the normally closed relay switch 50, conductor IN, the normally opened switch 28, conductor I02, the coil of the relay 45, conductor I03, the normally opened switch 52, conductors I04 and I05, normally closed switch 41, and conductor I06. As an al- I ternative, the relay 45, once actuated, closes the switches 44, after which the energization of the relay 45 is self supported through conductors I00 and I01, the lower of the switches 44, conductor I03, switches 52 and 41 and conductors I05 and I06.

In addition to the energization of the relay 45 being self supporting, current is passed through the heater coil 48 from the lower of the switches 44 through conductors I03 and I06. The upper of the switches 44 actuates the bell and alarm through conductors I00, I01, IIO, switch 26, and conductors I05 and I06 as controlled by the timer switch 41.

The normally closed relay switch 26 is held open by the coil 53a as described in connection with the trip beam 25 located where it will detect the release of the ball. The switch 26 is disposed preferably in the foul signal circuit 46 so that it does not interfere with the action of the relay 45, but rather cooperates with its action, being in series with the switch 44 thereof.

The relays 53a and 53b differ from relay 53 in that they act quickly but have a delayed recovery from their resting position once the resting position is attained.

For a better understanding of the general organization of the photo-electric circuits as they control the relays, it is the intention to use the beam 23 and relay device 52, 53 to lock out the system instantly whenever the ball goes through and to return the system to operation instantly when the ball clears the beam 23. The lo'wer or wide beam relay device 50, 5| is instantly responsive to slight or partial interruptance of the beam 24. Until the beam 21 has been interrupted the relay device 44, 45 may be closed by the interruptance of the beam 24 alone and held closed by the timer 41, 40. Then, when the ball trips the beam 25, signifying that it has been released and put into play, the switch 26 closes and operates the signals 40 and 5| to indicate that the infraction interrupting the beam 24 was a foul. 0n the other hand, if a foul has not been committed until after the [ball interrupts the trip beam 25, closure of the switch 26 merely sets up the circuit controlled by the relay 45 and the lower beam registers a foul if committed before the ball interrupts the beam 21.

Referring further to Fig. 3, and the details of the circuit controlling the relay device 50, 5| including the lower or wide beam 24, this circuit is designed to be extremely sensitive, sufficiently so, that a puif of cigarette smoke of low intensity or a light interruptance of less than 10% of the beam will set off the system even though the system is adjusted on the safe side of a resting condition, thus providing a detector which can be used in fire alarm systems and other connections as well as the one shown herein for foul'detection,

In the particular system illustrated, although a vacuum envelope can be used, an electron emission device, preferably a gas-filled envelope of the hot cathode, tetrode type such as an R. C. A. Thyratron #2050 or #2051 tube is employed wherein the usual anode (3) 6|, cathode (8) 62 heated by the filament (2) (7) 63 and control grid (5) 65 are provided along with a grid (6) 64 which will be referred to hereafter as the screened grid.

The system is powered preferably by a 120 watt.

auto transformer 66 having a low voltage secondary 61 connected in circuit with the filament 63, with or without a filament control (not shown), which control is preferably dispensed with for the sake of simplicity and economy, as being not indispensable.

The anode 6| is connected in circuit with one end 10 of the auto transformer 56 through the relay 5| as bridged by a condenser II to prevent chattering in the coil. This end 10 of the auto transformer 66 may be referred to as the positive" end since the tube 66 is inherently a half wave rectifier in that the current in the anode circuit 6| has a direct current component flowing half the time, so to speak, f om the anode to the cathode, the electron flow being in the opposite direction. a

By way of augmenting the flow of electrons through the tube from the cathode 62 to the anode 6f, the screen grid 64 and cathode are connected to the positive side of the filament (7) 63 to provide greater cathode area and reduce capacities between the filament and anode, thereby providing a large potential or path for electron emission to keep the coil of the relay 5| energized. Although 120 volt A. C. current is employed, the positive end may be the positive pole of a 120 D. C. pulsating current substituted to provide the essential characteristics herein discussed.

A center tap l2 separates the auto transformer into unbalanced components, namely, 61 volts and 59 volts, as indicated. This tap is connected directly to the anode 13 of the photoelectric cell 36, the 59 volt span being disposed between the tap 12 and the positive end 10.

The electron flow in the tube is controlled by the control grid 65 connected to the cathode 14 of the photo-electric cell 36. This connection in turn is negatively biased through a- 15 megohm resistor 15 in circuit with the center or movable tap of a 400 ohm potentiometer 16, one end 11 of which is connected to the negative pole of the auto transformer 66. The other end 80 of the potentiometer 16 is connected to the positive side of the filament 63 along with the screened grid and cathode, and this connection 8| is bridged to the anode 13 of the cell 36 by a 500 ohm resistor 82.

The characteristics of the resistor 15 are determined by the type of cell 31 employed, having preferably substantially the same current characteristic as the cell when the cell is fully illuminated. Then th potentiometer I5 is adjusted to accommodate the cell characteristics and to a point where the control grid has control of the tube 60 when the cell is illuminated by the full beam.

Thus the control of the tube which permits electron emission and current flow to energize the relay 5| is due to the setting of the potentlometer in relation to the value of the light falling upon the cell 36. Electron flow through the cell is at the highest, and since the current through the cell is operating in relation to the center tap which is less negative than that derived through the resistor 15, the control grid 65 of the tube 60 is less negativ than it should be to lose control of the tube.

When the cell 36 is shadowed the current flow through the cell lowers, and the negative pole I8 of the transformer, through the resistor 15, swings the 'bias on the control grid 65 to increase the negative characteristic thereof with respect to the cathode 62 and the control grid loses control of the tube during the negative or off-cycle of the current when current is not flowing through the tube, the anode of the tube having current only during one-half of the A. C. cycle.

The photo-electric circuit controlling the relay 53 as regards the interruptance of the beam 23 is a peak-interruptance circuit employing an R. C. A. tube # 41, 83, in whichthe photo-electric cell 34 is connected between the negative pole 18a of the auto transformer 66a and a positive tap 84 with the cathode 14a biased negatively by the negative pole 1811 through a 15 megohm resistor 15a to lose control of the tube 83 through the control grid 85 connected thereto when the light beam 23 is interrupted and the cell 34 darkened. The relay 53 is de-energized when the cell 34 is darkened.

Circuits like the one just described for cell 34 can be used to control the operation of relays 53a and 53b with regard to interruptance of beams 25 and 2'! respectively.

A further point of intent regarding the operating characteristics of the present invention is the one relating to sudden drops in the line voltage in the supply current. Both the lower beam 24 circuit and the upper beam 23 circuit are af-' fected by a voltage drop. However, the lower beam circuit as described is less sensitive to voltage drops than the peak interruptance circuit employed with the upper beam and therefore the switch 52 is opened by cle-energization of the relay 53 before the switch 50 is dropped by the relay 5|. Thereby the effect is substantially the same as though a ball interrupted the top beam 23 before interrupting the lower beam 24. No false fouls are called, which might otherwise occur with voltage drops.

Many of the steps of operation have already been described, but, in review, when a player advances to the foul line l2 to place the ball in play by delivering it down the alley in the direction of the pins l6, any infractions of the rules of play at the foul line will be detected by the beam 24 and registered by the relay 45 closing the switch 44 and sustaining the closure as timed by the timer 41. Whether the ball has been released before or after the infraction, the registry will be established since, if the ball interrupts the beam 23, the relay 45 is released or locked out only to let the ball go through and, if the infraction takes place or continues to exist after the ball has been released, the moment the upper beam 23 is reestablished the relay 45 will be energized.

Energization of the relay 45, however, does not sound the signal and register the foul immediately unless the beam 25 i dispensed with, in which case the foul will be immediately recorded. If the beam 251s employed in any par- 7 ticular installation, the recording or the foul will not be made until the beam 25 is interrupted and the switch 26 permitted to close.

The beam 25, when employed, is installed far enough down the alley that it is unlikely that a ball will be thrown over it, and low enough upon the alley to catch the ball rolling past it. Although it is desirable to have the beam 25 as close to the foul line as possible to apprise the player of his foul as soon as possible for psychological reasons, the distance the beam 25 is beyond the foul line is not critical so long as a slow-moving ball will interrupt it within the timing period of the timer 41. Thus a foul is registered and then recorded if the ball has been put into play.

In order to prevent a player committing an intentional foul to better his chances on a second try or to prevent facetious fouling merely to work the apparatus after the play of the ball has been completed, it is preferred that a beam 21 be located just in front of the pins to remove the foul detector from operation at or shortly after the ball has struck the pins Hi. This particular arrangement is described in our above mentioned copending application.

In some respects we are not able to account fully for the improved results which are obtained by the apparatus and arrangement of elements and circuits of this invention, and it should be understood that any attempt to analyze the theory or theories believed to be impossible for these results is to be construed not as defining a mode of operation but merely as a possible explanation of certain physical, electrical or capacity phenomena which have been observed.

Although certain embodiments and preferred arrangements of the elements of the present invention have been shown and described herein, it will be apparent to those skilled in the art that various uses, modifications and changes may be made without departing from the spirit and substance of the invention, the scope of which is commensurate with the appended claims.

What is claimed is:

1. In a signalling device for bowling alleys or the like having a foul line, a signal circuit including a signal and two switches one of which is controlled by a relay, means for detecting infractions of rules 06 play at the foul line for actuating said relay to close said circuit, timer means for maintaining closed the circuit thus closed for a predetermined time, and means for closing the other switch when a ball passes a predetermined point on the alley beyond the foul line.

2. In a signalling device for bowling alleys or the like havin an areaway for foot movement of a player and a foul line, two substantially parallel rays of undulating energy extending from one side of the alley to the other side, one at the foul line and the other above it, means responsive to interference with each ray including two relays, a control circuit including the switches of the two relays connected in series, a signal circuit controlled by said control circuit, a third relay having an open switch in said signal circult, and means responsive to the passage of the ball down the alley beyond the foul line for actuating said third relay to close said open switch.

3. In a signalling device for bowling alleys or the like having an areaway for foot movement of a player, two substantially parallel vertically 8 spaced beams of undulating energy extending from one side of the alley to the other at the foul line, circuit means including a signal, electron means responsive to an interruption of the lower beam for closing said circuit, electron means responsive to an interruption of the upper beam for opening said circuit, the last electron means bein more sensitive to drops in line voltage than the first mentioned electron means.

4. In a signalling device for bowling alleys or the like having an areaway for foot movement of a player, two beams of undulating energy projected across the alley at the foul line, one of said beams being located above the other and obscured by a bowling ball when the other beam is also obscured, means for signalling a foul including an electrical circuit, electron discharge means responsive to interference with the lower beam for closing a portion of said circuit, electron discharge means responsive to interruption of the upper beam'for opening a portion of said circuit, means for holding said circuit closed when closed by said first electron discharge means in absence of interruption of the upper beam, and means for closing the rest of the circuit after the ball has progressed down the. alley beyond the foul line.

5. In a signalling device for a game played with a moving object and a circuit having a plurality of interconnected switches therein, means for controlling the operation of said switches in relation to the position of a player with respect to the foul line, a relay controlled by said circuit, a signal circuit including a switch of the relay, and switch means for rendering the signal circuit inoperative when the object reaches a predetermined position with respect to the foul line.

6. In a signalling device for bowling alleys or the like having an areaway for foot movement of a player and a foul line, two substantially parallel vertically spaced beams of undulating energy extending across the alley at approximately the foul line, a signal means, circuit means for actuating the signal, electron means connected in said circuit means responsive to an interruption of the lower beam for actuating the signal, electron means connected in said circuit means responsive to an interruption of the upper beam for removing the signal from actuation, said last means being more sensitive to drops in line voltage than the first mentioned electron means.

7. In a signalling device for bowling alleys or the like having an areaway for foot movement of a player and a foul line, two substantially parallel vertically spaced beams of undulating energy extending across the alley at approximately the foul line, a signal means, circuit means for actuating the signal, electron means connected in said circuit means responsive to slight interruption of the lower beam for actuating the signal, electron means connected in said circuit means responsive to complete interruption of the upper beam for removing the sighail from actuation.

8. In a foul detecting and indicating system for bowling alleys, a normally inoperative foul signaling device, an operating circuit for the signaling device which includes a normally open switch, electro-magnetically operated means for operating the signal circuit switch, a circuit for said electro-magnetically operated signal-circuitswitch-operating-means and which, circuit, includes a serially connected pair of switches, one

of said pair of switches being normally open and the other of which is normally closed, separate electro-magnetically operated devices for independently operating said last named switches, another circuit for said electro-magnetically operated signal switch operator and which includes a normally open switch under control of the last said electro-magnetically operated switch operator, whereby to provide a holding circuit for maintaining the said electro-magnetic signal switch operator energized independently of said pair of switches after initial energization by coincidental closing of said pair of switches, light wave responsive control devices for independently controlling operation of said electro-magnetically operated devices, and means for projecting light waves from side to side of a bowling alley above and parallel to the foul line thereof and below the top of a bowling ball rolled over the foul line, said light wave responsive control devices each being subject to projected light waves that will be intercepted by a bowling ball rolled over the foui line.

9. In a, foul detecting indicating system for bowling alleys, a normally inoperative foul signaling device, an operating circuit for the signal which includes a normally open switch, electromagnetically operated means for operating the signal circuit switch, a circuit for said electromagnetically operated signal circuit switch operating means and which circuit includes one normally open switch and one normally closed switch, separate electro-magnetically operated devices for independently operating the last said switches, light wave responsive cotnrol devices for .independently controlling operating of said last named electro-magnetic switch operators, and means for projecting light waves from side to side of a bowling alley above and parallel to the foul line thereof and below the top of a bowling ball rolled over the foul line, said light wave responsive control devices each being subject to projected light waves that will be intercepted by a bowling ball rolled over the foul line, the ,said light wave responsive control devices being positioned one directly above the other and in which the upper thereof is directed to be acted upon by light rays projected longitudinally of the foul line in a plane near the maximum diameter of a bowling ball rolled over the foul line. I

10. In a, signalling device for bowling alleys or the like having a foul line, a signal, circuit means for actuating said signal including a plurality of switches, means for actuating one of the switches when an infraction of the rules of play occurs at the foul line to make ready the circuit to register a foul, means for actuating another of said switches when a ball has passed a predetermined point to complete the circuit and actuate said signal, and means for removing said circuit means from signal actuating condition when the ball has passed a second predetermined point.

11. In a signalling device for bowling alleys or the like having a foul line, a signal, circuit means for actuating said signal including a plurality of switches, means for actuating one of the switches when an infraction of the rules of play occurs at the foul line to ready the circuit means to actuate the signal, means for actuating another of said switches when a ball has passed a predetermined point to complete the circuit means to actuate the signal, and means for actuating another of said switches for removing the circuit mean-s from signal actuating condition after a predetermined period of time.

12. In a signalling device for bowling alleys or the like having a foul line, equipment for said alley including a foul signal, means for actuating the equipment including a. plurality of switches, means for actuating one of said switches with an infraction of the rules of play occurs at the foul line and including an element sustaining said actuation for a predetermined length of time, means for actuating another one of the switches when a ball has been put into play on the alley, said equipment being actuated when the two switches are in the state of being actuated at the same time.

13. In a signalling device for a bowling alley or the like, means responsive to the presence of an object at a predetermined point upon the alley, a second means responsive to the passage of a ball past a predetermined point upon the alley, a signal, and circuit means for actuating said signal controlled by said responsive means, said circuit means actuating said signal when the first mentioned responsive means responds to presence of an object in absence of the second responsive means being responsive to the passage oi the ball, and means for holding the first mentioned responsive means in responsive condition for a period of time after the responsive condition is established.

14. In a signalling device for bowling alleys or the like having an areaway for foot movement of a player and a foul line, means for detecting infractions of the rules of play at the foul line including an electron emission device controlling a relay and a timer for delaying recovery of said relay, a signal circuit means including the switch of said relay, an open switch in said circuit means, and means responsive to the passage of a ball for closing said switch when a ball has been put into play beyond said foul line.

15. In a foul detecting and indicating system for bowling alleys, a normally inoperative foul signaling device, an operating circult for the signal which includes a normally open switch, electromagnetically operated means for operating the signal circuit switch, 2, circuit for said electromagnetically operated signal circuit switch operating means and which circuit includes one normally open switch and one normally closed switch, separate electromagnetically operated devices for independently operating the last said switches, light wave responsive control devices fOr independently controlling operation of said last named electromagnetic switch operators, and means for projecting light waves from side to side of a bowling alley above and parallel to the foul line thereof and below the top of a bowling ball rolled over the foul line, said light wave responsive control devices each being subject to projected light waves that will be intercepted by a bowling ball rolled over the foul line, said light ray responsive control devices being so arranged that a bowling ball rolled over the foul line will successively interrupt the projected light rays thereto, and in which the light ray responsive device affected by projected light waves second interrupted by a bowling ball operates to set the signal in action responsive to interruption of light waves thereto and dependent upon a signal operative condition of the other light wave responsive device, and in which the last said light ray responsive device is operative responsive to interruption of light rays thereto to nullify the effects of a, signal operating condition of the 11 ment associated with the alley including means for disclosing commission of a foul and a foul line across which a bowling ball is delivered by a bowler when put into play, an apparatus including a device actuated by a body such as a bowlers foot present at the foul line, a timer device for maintaining said actuation for a predetermined period of time, a, device actuated by a body such as a ball put into play beyond the foul line, and means controlled by the joint operation of two of said devices for operating said equipment in which one of the two devices is the ball actuated device.

JAMES A.'MACLAGAN. THADDEUS A. WALSH.

REFERENCES CITED The following references are of record in the file of this patent:

v UNITED STATES PATENTS Number Name Date 2,170,157 Pray Aug. 22, 1939 2,162,508 Knowles June 13, 1939 2,231,621 Goodridge Feb. 11, 1941 2,202,67-1 Seaman May 28, 1940 2,037,671 Yannes Apr. 14, 1936

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