US2282132A - Electrical timing mechanism - Google Patents
Electrical timing mechanism Download PDFInfo
- Publication number
- US2282132A US2282132A US2282132DA US2282132A US 2282132 A US2282132 A US 2282132A US 2282132D A US2282132D A US 2282132DA US 2282132 A US2282132 A US 2282132A
- Authority
- US
- United States
- Prior art keywords
- switch
- watches
- race
- tape
- stop
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 230000000295 complement Effects 0.000 description 6
- 230000004075 alteration Effects 0.000 description 4
- 230000000994 depressed Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 230000004301 light adaptation Effects 0.000 description 4
- 230000003247 decreasing Effects 0.000 description 2
- 238000009429 electrical wiring Methods 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 230000001264 neutralization Effects 0.000 description 2
Images
Classifications
-
- G—PHYSICS
- G04—HOROLOGY
- G04F—TIME-INTERVAL MEASURING
- G04F8/00—Apparatus for measuring unknown time intervals by electromechanical means
- G04F8/08—Means used apart from the time-piece for starting or stopping same
-
- G—PHYSICS
- G07—CHECKING-DEVICES
- G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
- G07C1/00—Registering, indicating or recording the time of events or elapsed time, e.g. time-recorders for work people
- G07C1/22—Registering, indicating or recording the time of events or elapsed time, e.g. time-recorders for work people in connection with sports or games
- G07C1/24—Race time-recorders
Definitions
- Our present invention relates to improvements in electric timing mechanisms, including electromagnetic means for controlling a series or number of stop watches, and involving a portable equipment adapted for use in connection with horse-races, boat-races, and other sporting events, as well as for timing industrial operations.
- a portable equipment adapted for use in connection with horse-races, boat-races, and other sporting events, as well as for timing industrial operations.
- our invention we refer herein to the adaptation of the portable timing mechanism as employed at track meets, and especially the timing of a foot race.
- the portable equipment may be situated at a desirable and convenient location adjacent the track, in order thatI the start of the race may be signaled by the use of the customary starting gun, and the finish of the race indicated by the customary breaking of a tape, light cord, or other usual means.
- the firing of the starting gun automatically controls the starting of a number or series of stop watches through the instrumentality of complementary electro-magnetic control devices.
- Two of the series of stop watches are automatically controlled and stopped at the finish of the race by the winning contestant as he breaks the tape, or'crosses the nish line, thus providing a dual indication of the time of the winner, and eliminating the chance of inaccurate timing.
- the remaining stop watches are stopped by means of manually operated switches or push-buttons manipulated by judges who stand in position to see the finish of the race, and thus give the time of each of the following contestants. While we have shown six stop watches, including the dual indicators for the winner of the race, it will be understood that the number of remaining stop watches may be increased or decreased in accord with the number of contestants in a race.
- Figure 1 is a conventionalized diagram of the electrical wiring and electrically operated control devices employed in carrying out our invention, all of the switches being shown in open position.
- Figure 2 is a view showing part of the portable equipment of our invention, including the starting gun with its starting switch and the manually controlled stop switches for use at the iinish of the race, together with a carriage or wheeled cabinet in which the equipment may be stored and from which the wires, cords, cables and other devices may be withdrawn for use.
- Figure 3 is a top plan view of the balanced mechanical parts involved in the operation of the automatically controlled tape-switch at the finish of the race which switch controls two of the stop watches of the series.
- Figure 4 is a face view of the tape-switch mechanism of Figure 3, showing the circuit wires connected thereto.
- Figure 5 is an enlarged detail sectional View of an interior part of the portable cabinet, show- Y ing the electro-magnetic control devices of one of the stop watches.
- Figure 6 is a top plan View showing one of the stop watches with its hammer that engages the crown of the watch for controlling the mechanism of the watch.
- the series of stop watches are designated as l, 2, 3, 4, 5, and t, and they are controlled loy the complementary solenoids 1, 8, 9, i0, Il, and i2 that are included in the operating circuit 0, which includes the battery B and a cut-out or battery switch i3, which is closed when the mechanism is in use.
- the starting gun G (Fig. 2) has an automatically closed starting switch M (Fig. l.) included in a starting circuit S that includes the battery B and the cut-out switch I5, which battery switch is also closed when the mechanism is to be used.
- the wires of the six solenoids and the lead wires of the starting switch M are connected with the starting circuit through the closing of eight circuit makers l5, Il, I8, IQ, 28, 2l, Z2, and 23, and these circuit makers may be the usual hand switches as indicated, or if desirable one or two knife switches may be utilized for this purpose.
- the main wire O of the operating circuit O is connected with the starting circuit through. the relay 24 in the starting circuit and the relay switch 25, this relay being energized to close the switch 25 when the starting switch I4 is automatically closed as the signal gun G is red for the purpose of starting the race.
- the solenoids 1 and 8 simultaneously control the stop watches I and 2 to time the winner of the race, and the remainder of the stop watches 3, 4, 5, 5, controlled by the solenoids 9, I0, II, vand I2, are adapted for selective use, depending upon the number of contestants in ⁇ the race.
- Numerals 26, 21, 28, 29, indicate manually controlled switches, and 30 is the tape switch in the finish circuit F. These four switches 26, 21, 28, 29 are closed if and when it is desired to stop all of the watches when the tape is broken by the winner, and thus time the winner with a plurality of watches.
- the primary use of the invention is to employ the switch 3
- , 32, 33, 34, as shown are connected with the respective solenoids 9, I0, II, and I2, and they are also connected with a wire of the nish circuit F that includes the open, balanced tapeswitch 30 that is automatically closed when the winner breaks the tape at the nish of the race, and thereby stops the stop watches I and 2, to indicate the time of the winner.
- Starting circuit and other Wires, cords, or cables may be wound upon a reel, or reels, that may be rolled along the ground to their desired locations for use in the timing operations.
- the stop watches are mounted on the upper face of a board or plate 36 located in the upper part of the cabinet and adjustable holders 31 for the watches are provided with adjusting screws 38 for use in accurately placing the watches.
- the crown C of each watch is depressed to start, stop, and reset the watches, and
- FIG. l a re-setting switch 39 is shown in the starting circuit, which switch when closed causes the several solenoids to actuate the operating mechanism that depressed the crowns C.
- This operating mechanism includes a hammer 4D (Figs. 5 and 6) having a rubber or cushioned head 4
- a spring 46 is connected to the lever arm and anchored to the board 35 for holding the head out of conmounted therein to receive the push buttons 3
- the other arm 41 of the bell crank lever is pivotally connected at 48 to a longitudinally adjustable, and substantially long connecting rod 49 rigid with the armature 59 of the solenoid (as 1) and a turnbuckle 5I couples this rod with the pivot link 52.
- the stop watch is thus mounted at a substantial distance from the magnetic eld of the solenoid to prevent magnetic interference with the operation of the watch movement,'and the adjustable turnbuckle is utilized for varying the length of the connecting rod to adjust the stroke of the solenoid plunger or armature.
- the hammer-head is also adjustable with relation to the crown of the watch for the purpose of insuring accuracy in the control of the operation of the watch.
- FIGS 3 and 4 we have disclosed one form of support for an end of the tape T, which includes a balanced or equalized arrangement of the open switch 3
- the tape is fastened to a horizontally extending and comparatively long U-shaped yoke'53, which is rigidly mounted on a switch-arm 54 that is pivoted at 55 on a supporting board or plate '56.
- This board or plate is a stationary support fixed in suitable manner at the iinish line of the race track, and the electric wires from this tape-switch are of suitable length to extend to terminals in the portable cabinet or carriage in which the stop Watches are mounted.
- the movable switch arm 54 is provided with a contact point complementary to a stationary contact point mounted on a suitable bracket 51 xed to the supporting board 56.
- the movable switch-arm 54 is balanced with the tape-switch open, by means of a spring 58 connected at one end with the arm, andthe other end of the spring is connected to the adjoining end of an adjusting screw 59 mounted in a nut 60 fixed on the board 56.
- the tension of the spring may be adjusted for accurately positioning the lever or switch-arm, and a stop 6
- a second weaker spring 62 is also ebn- ⁇ nected at one end to the switch arm near its free end, and the other end of this spring is anchored to a balancing lever 63, pivoted at B4 on the board 5S.
- This lever is loosely pivoted at ⁇ Sil., but it is provided with a friction brake in the nature of a spring 65, coiled about the pivot 64 and interposed between the hub-portion of the lever and a hanged Washer 6E.
- the friction or braking action applied to the lever by tension of the spring 65 may be varied to adjust the tension of the auxiliary or balancing spring 62.
- the tape T may be stretched taut with the pivoted switch arm balanced and the tape-switch open.
- the auxiliary spring 62 may be slightly extended by movement of the resiliently held friction lever 63 to impose a slight extra or overbalancing tension on the tape, which will resist pressure of wind on the stretched tape and thus prevent accidental closing of the tape switch.
- the tape-switch is closed when the winner of the race hits the tape and pulls the contact point of the pivoted switch arm into contact with the stationary contact point, thus closing the circuits of the two solenoids 'I and 8 and stopping the dual watches I and 2.
- the springs 58 and 62 which pull the movable switch-arm into position of Figure 4.
- timing equipment may be adapted to be utilized in other contests and sporting events and similar timing purposes. While we have illustrated and described specific niechanie cal devices in connection with the electrical equipment of our invention, it will be understood that changes and alterations may be made within the scope of our appended claim without departing from the principles of our invention.
- An electric race-timing mechanism including a series of stop watches, a source of electricity, means including a group of solenoids each adapted to start and stop one of said watches, a solenoid-operating circuit connected to said source and said solenoids being connected in parallel relation in said circuit, manually operated switches in said solenoid operating circuit, one switch for each solenoid, a relay-operated switch in said solenoid-operating circuit, a relay-operating circuit for energizing said relay including a switch to be closed at the starting of a race, a tapeoperated nish switch in series with said source and with two of said solenoids, said tape-operated switch being in parallel with the relay-operated switch and the said manual switches, whereby said two solenoids are energized by the winner upon reaching the finish-tape.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Unknown Time Intervals (AREA)
Description
Z6 Z7 Z8 May 5, 1942. E. P. HALToM x-:rAL
ELECTRICAL TIMING MECHANISM Filed May 1o, 1940 s sheets-sheet 1 VON) llt,
gam"
lLIL blt. L L.
Snucnfor May 5, 1942- E. P. HALTM ET AL 2,282,132
ELECTRICAL TIMING MECHANISM Filed May 10, 1940 3 Sheets-Sheet 2 K lnveutors Eva/mfr P//fa ron Bg GEORG; Lfp//ve/m/w May 5, 1942- Y E. P. HALToM ET AL 2,2825132 ELECTRICAL TIMINGMECHANISM Filed- May l0, 1940 3 Sheets--Sheel 3 Bnventor Y Jij (ltfornegb Patented May 5, 1942 ELECTRICAL TIMING MECHANISM Evanda 1. Haltom and George L. Ledingham, Fort Worth, Tex.
Application May 10, 1940, Serial No. 334,500
(C1. ll- 18) 1 Claim.
Our present invention relates to improvements in electric timing mechanisms, including electromagnetic means for controlling a series or number of stop watches, and involving a portable equipment adapted for use in connection with horse-races, boat-races, and other sporting events, as well as for timing industrial operations. For convenience in illustration and description of our invention we refer herein to the adaptation of the portable timing mechanism as employed at track meets, and especially the timing of a foot race.
For such an event the portable equipment may be situated at a desirable and convenient location adjacent the track, in order thatI the start of the race may be signaled by the use of the customary starting gun, and the finish of the race indicated by the customary breaking of a tape, light cord, or other usual means.
For positive and accurate timing of the race, the firing of the starting gun automatically controls the starting of a number or series of stop watches through the instrumentality of complementary electro-magnetic control devices. Two of the series of stop watches are automatically controlled and stopped at the finish of the race by the winning contestant as he breaks the tape, or'crosses the nish line, thus providing a dual indication of the time of the winner, and eliminating the chance of inaccurate timing.
The remaining stop watches, here shown as four in number, are stopped by means of manually operated switches or push-buttons manipulated by judges who stand in position to see the finish of the race, and thus give the time of each of the following contestants. While we have shown six stop watches, including the dual indicators for the winner of the race, it will be understood that the number of remaining stop watches may be increased or decreased in accord with the number of contestants in a race.
In the specific adaptation of our invention illustrated in the accompanying drawings we employ a standard type of stop watch, the hands of which are started, stopped, and re-set or returned to neutral position at will, and these functions oi lthe series of Watches are controlled by our novel combinations and arrangements of electrical equipment, as will be hereinafter more fully pointed out and claimed.
In the accompanying drawings we have illustrated one complete example of the psysical embodiment of our invention, but it will be understood that changes and alterations may be made in these exemplifying disclosures within the scope of our claim without departing from the principles of our invention.
Figure 1 is a conventionalized diagram of the electrical wiring and electrically operated control devices employed in carrying out our invention, all of the switches being shown in open position.
Figure 2 is a view showing part of the portable equipment of our invention, including the starting gun with its starting switch and the manually controlled stop switches for use at the iinish of the race, together with a carriage or wheeled cabinet in which the equipment may be stored and from which the wires, cords, cables and other devices may be withdrawn for use.
Figure 3 is a top plan view of the balanced mechanical parts involved in the operation of the automatically controlled tape-switch at the finish of the race which switch controls two of the stop watches of the series.
Figure 4 is a face view of the tape-switch mechanism of Figure 3, showing the circuit wires connected thereto.
Figure 5 is an enlarged detail sectional View of an interior part of the portable cabinet, show- Y ing the electro-magnetic control devices of one of the stop watches.
Figure 6 is a top plan View showing one of the stop watches with its hammer that engages the crown of the watch for controlling the mechanism of the watch.
In the conventional diagram of Figure l, the series of stop watches are designated as l, 2, 3, 4, 5, and t, and they are controlled loy the complementary solenoids 1, 8, 9, i0, Il, and i2 that are included in the operating circuit 0, which includes the battery B and a cut-out or battery switch i3, which is closed when the mechanism is in use.
The starting gun G (Fig. 2) has an automatically closed starting switch M (Fig. l.) included in a starting circuit S that includes the battery B and the cut-out switch I5, which battery switch is also closed when the mechanism is to be used. The wires of the six solenoids and the lead wires of the starting switch M are connected with the starting circuit through the closing of eight circuit makers l5, Il, I8, IQ, 28, 2l, Z2, and 23, and these circuit makers may be the usual hand switches as indicated, or if desirable one or two knife switches may be utilized for this purpose.
The main wire O of the operating circuit O is connected with the starting circuit through. the relay 24 in the starting circuit and the relay switch 25, this relay being energized to close the switch 25 when the starting switch I4 is automatically closed as the signal gun G is red for the purpose of starting the race.
The solenoids 1 and 8 simultaneously control the stop watches I and 2 to time the winner of the race, and the remainder of the stop watches 3, 4, 5, 5, controlled by the solenoids 9, I0, II, vand I2, are adapted for selective use, depending upon the number of contestants in` the race. Numerals 26, 21, 28, 29, indicate manually controlled switches, and 30 is the tape switch in the finish circuit F. These four switches 26, 21, 28, 29 are closed if and when it is desired to stop all of the watches when the tape is broken by the winner, and thus time the winner with a plurality of watches. The primary use of the invention, however, is to employ the switch 3|) for dual control in simultaneously and automatically stopping watches I and 2 to time the winner; and thereafter individually time the succeeding runners as they also nish the race. The runners who nish after the winner are timed by time-keepers who hold in their hands manually controlled switches 3|, 32, 33, 34. Thus if there were ve contestants in the race (the maximum number that may be timed by the equipment herein indicated) the four manually operated switches 2S, 21, 28, and 29, are left open in preparation for the timing operations.
The four selective circuit closers or switches 3|, 32, 33, 34, as shown are connected with the respective solenoids 9, I0, II, and I2, and they are also connected with a wire of the nish circuit F that includes the open, balanced tapeswitch 30 that is automatically closed when the winner breaks the tape at the nish of the race, and thereby stops the stop watches I and 2, to indicate the time of the winner.
The timing of the other four contestants in' solenoids 1 and 8 are connected by a shunt y wire 3|a, and the wire of solenoid 1 is extended to wire F of the nish circuit, therefore it will be obvious that closing of switch 30 will energize solenoids 1 and 8 resulting in another action which stops these dual-controlled watches I and 2 thereby timing the winner of the race.
Assuming that the four remaining contestants nish or cross the line successively, the four judges holding the push button switches 3|, 32, 33, and 34, close these switches successively to close the individual circuits of the push buttons, and energize the respective solenoids 9, I0, I I, and I2, thereby stopping the watches 3, 4, 5, and 5, to time the losers of the race.
As indicated in Figure 2 all of the circuits or wires are connected to terminals within a carriage or wheeled cabinet W which may be trundled to a suitable spot with relation to the track by use of handles, one of which is indicated at H and the cabinet has a hinged lid or window L so that the watches are readily visible when the lid is closed. A pocket is provided in the front of the cabinet, and a suitable rack 35 is.
starting circuit, and other Wires, cords, or cables may be wound upon a reel, or reels, that may be rolled along the ground to their desired locations for use in the timing operations.
The stop watches are mounted on the upper face of a board or plate 36 located in the upper part of the cabinet and adjustable holders 31 for the watches are provided with adjusting screws 38 for use in accurately placing the watches. The crown C of each watch is depressed to start, stop, and reset the watches, and
Ain Figure l a re-setting switch 39 is shown in the starting circuit, which switch when closed causes the several solenoids to actuate the operating mechanism that depressed the crowns C.
This operating mechanism includes a hammer 4D (Figs. 5 and 6) having a rubber or cushioned head 4| located in position to contact with and depress the crown C, and by means of an adjusting screw 42 and nut 43 the head is mounted in the upper end of arm 44 of a bell crank pivoted on a suitable support at 45. A spring 46 is connected to the lever arm and anchored to the board 35 for holding the head out of conmounted therein to receive the push buttons 3|, A
tact with the crown, and for quickly retracting the head after it has imparted a hammer blow to the crown thus permitting prompt recoil of the crown. The other arm 41 of the bell crank lever is pivotally connected at 48 to a longitudinally adjustable, and substantially long connecting rod 49 rigid with the armature 59 of the solenoid (as 1) and a turnbuckle 5I couples this rod with the pivot link 52.
The stop watch is thus mounted at a substantial distance from the magnetic eld of the solenoid to prevent magnetic interference with the operation of the watch movement,'and the adjustable turnbuckle is utilized for varying the length of the connecting rod to adjust the stroke of the solenoid plunger or armature.
The hammer-head is also adjustable with relation to the crown of the watch for the purpose of insuring accuracy in the control of the operation of the watch.
In Figures 3 and 4 we have disclosed one form of support for an end of the tape T, which includes a balanced or equalized arrangement of the open switch 3|] that is automatically closed, when ,the tape is broken, to cause solenoids` 1 and 8 to be energized vand simultaneously stop the dual watches I and 2. The tape is fastened to a horizontally extending and comparatively long U-shaped yoke'53, which is rigidly mounted on a switch-arm 54 that is pivoted at 55 on a supporting board or plate '56. This board or plate is a stationary support fixed in suitable manner at the iinish line of the race track, and the electric wires from this tape-switch are of suitable length to extend to terminals in the portable cabinet or carriage in which the stop Watches are mounted. The movable switch arm 54 is provided with a contact point complementary to a stationary contact point mounted on a suitable bracket 51 xed to the supporting board 56.
The movable switch-arm 54 is balanced with the tape-switch open, by means of a spring 58 connected at one end with the arm, andthe other end of the spring is connected to the adjoining end of an adjusting screw 59 mounted in a nut 60 fixed on the board 56. The tension of the spring may be adjusted for accurately positioning the lever or switch-arm, and a stop 6| prevents undue movement of the pivoted arm. In order to insure a delicatev adjustment of, and
precision in, the closing movement of the tapeswitch, a second weaker spring 62 is also ebn-` nected at one end to the switch arm near its free end, and the other end of this spring is anchored to a balancing lever 63, pivoted at B4 on the board 5S. This lever is loosely pivoted at `Sil., but it is provided with a friction brake in the nature of a spring 65, coiled about the pivot 64 and interposed between the hub-portion of the lever and a hanged Washer 6E. Thus the friction or braking action applied to the lever by tension of the spring 65 may be varied to adjust the tension of the auxiliary or balancing spring 62.
By adjusting the screw 59 to vary the tension of spring 53 the tape T may be stretched taut with the pivoted switch arm balanced and the tape-switch open. After the switch arm is thus balanced the auxiliary spring 62 may be slightly extended by movement of the resiliently held friction lever 63 to impose a slight extra or overbalancing tension on the tape, which will resist pressure of wind on the stretched tape and thus prevent accidental closing of the tape switch.
As before pointed out, the tape-switch is closed when the winner of the race hits the tape and pulls the contact point of the pivoted switch arm into contact with the stationary contact point, thus closing the circuits of the two solenoids 'I and 8 and stopping the dual watches I and 2. Immediately after contact has been made it is broken by action of the springs 58 and 62 which pull the movable switch-arm into position of Figure 4.
While we have thus fully illustrated and described cne complete physical embodiment of our invention as applied to and used in timing a foot race involving ve contestants, it will be under stood that the equipment may be adapted for tim- `ing diiierent numbers of entrants in such a race;
and further, the timing equipment may be adapted to be utilized in other contests and sporting events and similar timing purposes. While we have illustrated and described specific niechanie cal devices in connection with the electrical equipment of our invention, it will be understood that changes and alterations may be made within the scope of our appended claim without departing from the principles of our invention.
Having thus fully described our invention, what we claim as new and desire to secure by Letters Patent is:
An electric race-timing mechanism including a series of stop watches, a source of electricity, means including a group of solenoids each adapted to start and stop one of said watches, a solenoid-operating circuit connected to said source and said solenoids being connected in parallel relation in said circuit, manually operated switches in said solenoid operating circuit, one switch for each solenoid, a relay-operated switch in said solenoid-operating circuit, a relay-operating circuit for energizing said relay including a switch to be closed at the starting of a race, a tapeoperated nish switch in series with said source and with two of said solenoids, said tape-operated switch being in parallel with the relay-operated switch and the said manual switches, whereby said two solenoids are energized by the winner upon reaching the finish-tape.
EVANDA P. HALTOM. GEORGE L. LEDINGHAM.
Publications (1)
Publication Number | Publication Date |
---|---|
US2282132A true US2282132A (en) | 1942-05-05 |
Family
ID=3432610
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US2282132D Expired - Lifetime US2282132A (en) | Electrical timing mechanism |
Country Status (1)
Country | Link |
---|---|
US (1) | US2282132A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2547214A (en) * | 1947-04-16 | 1951-04-03 | Westinghouse Electric Corp | Contact device |
US2843689A (en) * | 1954-06-07 | 1958-07-15 | Deering S Roberts | Device for temporarily closing a circuit |
-
0
- US US2282132D patent/US2282132A/en not_active Expired - Lifetime
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2547214A (en) * | 1947-04-16 | 1951-04-03 | Westinghouse Electric Corp | Contact device |
US2843689A (en) * | 1954-06-07 | 1958-07-15 | Deering S Roberts | Device for temporarily closing a circuit |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2590444A (en) | Bowling machine totalizer | |
US2283277A (en) | Golf swing indicator | |
US2282132A (en) | Electrical timing mechanism | |
US2500172A (en) | Hawaiian electric guitar with harmonic facilities | |
US2296508A (en) | Game scoring apparatus | |
US2531608A (en) | Bombing game | |
US2627415A (en) | Electrical automatic time control | |
US1055929A (en) | Registering system. | |
US2058712A (en) | Stop clock | |
US2148612A (en) | Electric target range | |
US2152598A (en) | Amusement apparatus | |
US2211617A (en) | Game apparatus | |
US2233026A (en) | Selector for phonographs | |
US2435141A (en) | Amusement game | |
US766353A (en) | Electric billiard-register. | |
US2085849A (en) | Time keeping and indicating | |
US3150361A (en) | Mail indicator and door signal | |
US2594103A (en) | Automatic electric time control | |
US2595048A (en) | Annunciator for games | |
US2057376A (en) | Regulating device for wireless receivers | |
US2019126A (en) | Amusement apparatus | |
US2419770A (en) | Plunger for pinball machines | |
US2541690A (en) | Radio time switch | |
US2577408A (en) | Automatic electric timing system | |
US2485721A (en) | Game apparatus |