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BE333461A
(h)
|
|
|
|
US1955616A
(en)
|
|
Signal device
|
|
US2045045A
(en)
|
|
Headlight blinker for daylight signals
|
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BE355284A
(h)
|
|
|
|
US1866422A
(en)
|
|
Electric switch device
|
|
US1786524A
(en)
|
|
Fire-alarm system
|
|
US307096A
(en)
|
|
Electric circuit for railroad-crossing gates |
|
US452281A
(en)
|
|
Railway signaling device |
|
US1561717A
(en)
|
|
Automatic crossing gate |
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US1197130A
(en)
|
|
Annunciator.
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|
US1498349A
(en)
|
|
Automatic railway-crossing signal
|
|
CN2718700Y
(zh)
|
|
急转弯公路汽车安全交会声光警示装置
|
|
US946202A
(en)
|
|
Electric signaling apparatus for railways.
|
|
US1255277A
(en)
|
|
Electric fire and burglar alarm.
|
|
US1169991A
(en)
|
|
Electric signaling system.
|
|
US457565A
(en)
|
|
Signaling-telegraph for cable railways |
|
US1901404A
(en)
|
|
Out-of-order signal
|
|
US1235242A
(en)
|
|
Fire-alarm.
|
|
BE539048A
(h)
|
|
|
|
US934284A
(en)
|
|
Electric signaling device.
|
|
US926437A
(en)
|
|
Automatic block-signal for trolley systems.
|
|
GB384029A
(en)
|
|
Improvements relating to traffic-control signals
|
|
US518525A
(en)
|
|
Automatic electric signaling device for crossings |
|
US1197273A
(en)
|
|
Electrical signaling system.
|
|
US1016670A
(en)
|
|
Listening-detector for telephone-lines.
|