US1921359A - Traffic signal - Google Patents
Traffic signal Download PDFInfo
- Publication number
- US1921359A US1921359A US428146A US42814630A US1921359A US 1921359 A US1921359 A US 1921359A US 428146 A US428146 A US 428146A US 42814630 A US42814630 A US 42814630A US 1921359 A US1921359 A US 1921359A
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- United States
- Prior art keywords
- tubes
- light
- color
- drum
- signal
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- 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
- 229910052754 neon Inorganic materials 0.000 description 12
- GKAOGPIIYCISHV-UHFFFAOYSA-N neon atom Chemical compound [Ne] GKAOGPIIYCISHV-UHFFFAOYSA-N 0.000 description 12
- 239000003086 colorant Substances 0.000 description 6
- 239000011521 glass Substances 0.000 description 6
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000005337 ground glass Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000008267 milk Substances 0.000 description 2
- 210000004080 milk Anatomy 0.000 description 2
- 235000013336 milk Nutrition 0.000 description 2
- 238000005192 partition Methods 0.000 description 2
- 239000004020 conductor Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229920000136 polysorbate Polymers 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08G—TRAFFIC CONTROL SYSTEMS
- G08G1/00—Traffic control systems for road vehicles
- G08G1/09—Arrangements for giving variable traffic instructions
- G08G1/096—Arrangements for giving variable traffic instructions provided with indicators in which a mark progresses showing the time elapsed, e.g. of green phase
Definitions
- the invention relates to a device for controlling traiiic, more particularly street trailc, by means of one or more colored surfaces, each of which is lighted at intervals. 5
- the advantage of such a device is that the signal device itself presents to the trafc an indication of its duration and of the time at which it will change.
- the invention relates more particularly to a device by means of which the above object can be realized in a very practical and simple manner, and moreover to a device which from a technical point of view has special advantages.
- the invention comprises light- 15. ing a number of colored surfaces and successively extinguishing the sources of light or the groups of sources of light.
- the device may comprise a casing suspended or placed upon a pedestal or column, or arranged in any other manner, and a number of sources of light, e. g., electric lamps, arranged in said casing or on said pedestal in such a manner that in case said lamps have been lit a surface or eld of a certain color is visible.
- sources of light e. g., electric lamps
- These lamps are connect- 25 ed, either separately or in groups, with a switching device that causes the lamps of a particular colored signal to be lit all together and to be extinguished in succession or in successive groups.
- the device may comprise one or more of such elds 0 of diiierent colors, e. g., for giving a red signal for stopping and a green,one for proceeding.
- the switching device may comprise a rotating controller drum, such asf-often used for electrical advertisementand the like.
- One switching device may be used for a plurality of apparatus. This switching device may be operated manually, electrically, or mechanically.
- lamps with'colored glass bulb In order to obtain the desired color effect, use may be made of lamps with'colored glass bulb, or
- Neon lights may be utilized advantageously.
- partition walls may be arranged between the sources of light in such a manner that the screen before the extinguished lamps receives no light or verir little light.
- connection between the sources of light and the switching de vice, and also the switching device itself may differ very much.
- the arrangement may be such that all lamps of one color are litat the same time and extinguished one after the other, and likewise groups of lamps may be extinguished in suc- ⁇ cession.
- the sequence in which the lamps or the groups of lamps are extinguished may vary, and
- the invention further relates to an improvement of devices as described hereabove, and in general to devices by means of which traffic may 05 be controlled with the aid of a number of differently colored and alternately appearing lights.
- the colored surfaces appear substantially inthe same plane. f It is evident that the signal controlby thismethod results in smoother and more efficient v traiiic flow, because the driver of the vehicle need only turn his eye towards one certain point. Furthermore, the device lookssmall and simple, which qualities are essential to trame control purposes.
- This invention may be realized in many ways.
- the sources of light for producing two colors e. g., red and green
- the whole may be set behind a screen of ground glass, milk glass, or other light-diffusive substance. The arrangement should be such that the sources of light for one color do not interfere with those for the other color.
- neon tubes are especially effective, because they do not needv colored transparent windows.
- the tubes for both colors, or for a plurality of colors, may be arranged alternately, and the connection may be such that the tubes for producing one color, after being lit, may be extinguished one after the other, whereupon the same operation occurs with the tubes for the other color.
- the sources o1' light or the tubes may be arranged in any position with respect to each other,
- connection i. e., the sequence in which they are extinguished
- the sources of light may for example be placed in concentric circles and the neon tubes may consist of concentric circular tubes.
- 'Ihe device may work in combination with others for different crossings, and they may also be combined with signal control devices for pedestrians.
- Signal devices according to the invention may be provided in a simple manner with means by which in case of need all signals may be placed manually, and/or automatically, for example, in order to pass the fire engines, street cars, or processions, or in case of accident. 'Ihis makes it possible to :dnd a solution for giving some prei- 110 v erence to the street car traic, which manner of controlling may be automatic by closing or interrupting contacts by the street car before the crossing in question.
- Figure 1 is a vertical, schematic section of a signal apparatus according to the invention.
- Fig. -2 is a front view of the indication apparatus.
- Fig. 3 shows schematically the diagram of connections for switching in and oi'the light sources.
- the apparatus comprises a cylindrical casing 1, constructed of durable material such as iron and having a diameter of about 60 centimeters. 'Ihe front of this casing is provided with a glass screen 2 or the like, and the back with a detachable plate 3.
- a disk 4 is arranged within the casing, said disk being made preferably of multiplex-wood or similar material, containing several perforations or openings and connected with the casing 1 by means of supports 16.
- Nine neon tubes 5-13 which are circularly bent and nest within one another are mounted on the said wooden disk 4.
- the odd numbered tubes may radiate a red light, and the even numbered tubes a green light.
- the electrodes of said tubes 5--13 pass through the perforations in the wooden disk 4 and thus they are arranged in the space which is accessible by means of the partition wall 3.
- the high voltage cables 14 connecting the various electrodes with the switching device enter into the said space.
- a screen 15 is 'arranged at the top in order to block out daylight and sunlight, so that the light signals will be clearly visible.
- the complete apparatus may be arranged on a pedestal 17 or against a wall by means of supports or be suspended from cables.
- Fig. 3 illustrates the diagram of connection of the device for lighting and extinguishing the neon tubes.
- the device comprises@1 controller drum 18 for short circuitingand lighting the neon tubes and contacts 19 sliding over said drum. These contacts 19 are connected with the high-voltage cables 14.
- the controller drum 18 is driven, via a reducing coupling 20, by an electromotor 21 having a predetermined number of revolutions which may be adjustable.
- the electromotor 21 is connected With the power network by the conductor 22 via fuses 23 and a switch 24. 'Ihe frame of the controller drum, the motor, and the transformers 25 and 26 are connected to ground, as is also one of the contacts 19.
- the available voltage (of 220 volts, for example) is stepped up by the transformers, which are connected in parallel, to the voltage necessary for lighting the neon tubes (such as 3500 volts)
- the transformers 25 and 26 are also connected in series with the neon tubes, so that for extinguishing the tubes it is necessary to only short circuit the latter.
- sparking on the controller drum 18 is considerably less than would be the case if the neon tubes were switched oi. In this manner, the life of the controller drum and the corresponding contacts is increased, since said parts are less subject to burning.
- the transformers may be considerably smaller, which is anadvantage when the available space is small.
- tacts 19 slide over the drum in such a manner, that with the exception of one contact, they come into contact with the body 18 of the drum or are out of contact with the said body. As soon as a contact comes in engagement with the body 18, one of the neon tubes is short circuited, and this short circuit is disconnected only when the said contact is broken. One ⁇ of the contacts 19 which is connected to groundl is in a continuous connection with the body of the drum.
- the controller drum is constructed so that when it is in rotation, at first the ve left contacts 19 cause the short circuit of five tubes (for example, the five tubes giving green light). At this moment, the four right contacts 19 are out of contact with the body 18, so that the other four tubes (e. g., the four tubes giving red light) are in operation. As the drum continues its rotation, the four right contacts are short circuited in succession, so that the corresponding four tubes are extinguished in succession. As soon as the last (inner) tube giving red light has been extinguished, the short circuit on the tubes giving green light is raised because the connection of the ve left contacts is broken and the green tubes will light. After some time, the tubes giving green light are short circuited one after another, and immediately thereupon the tubes gitfing red light begin to light again. At this moment, the drum has performed one revolution.
- the ve left contacts 19 cause the short circuit of five tubes (for example, the five tubes giving green light).
- the four right contacts 19 are out of contact with the body 18, so that the
- the transformers should be able to bear the short circuit on the tubes and are calculated so that they can endure the total short circuit.
- the controller drum 18 may be constructed so that the duration of the short circuit and that of the lighting of the tubes are mutually and independently adjustable. This may be effected, for example, by constructing the drum of some adjustably arranged rings, the number of which corresponds with the number of tubes or groups of tubes. Moreover, the contacts may be adjustably arranged on the said drum so that any variation is possible.
- the present invention also contemplates a signal which has only one light radiating surface, usually red. 1n this case, all of the concentric neon tubes shown in Fig. 2 will radiate red light. After they are all lit, they are gradually extinguished one at a time by means of the controller drum 18. It will be obvious that in this instance the controller drum 18 will diier from that shown in Fig. 3. In Fig. 3, it is necessary to light half the tubes and to extinguish them gradually, and
- the controller drum in this instance should have a continuous In the lowermost position, all the tubes are short circuited so that the traffic signal does not show any light, and the traic moves unhindered. In the next higher position, all the tubes will show a red light so that the traic is stopped. In the next higher position, one of the tubes is short circuited so that the total amount of surface illuminated red becomes smaller. This keeps on until the last or the uppermost position, as shown on the drum 18, when all the tubes are short circuited again, and the light radiating surface has disappeared. In the meantime, of course, the operators of the vehicle have been informed of the duration of the signal by the amount of illuminated surface visible to them.
- controller drum 18 may be manually moved so that'the proper tubes or number of. short circuited.' This can be veryeasily done by havingindexes on the controller drum to enable..
- the embodiment as described abovev tended to restrict the invention to tneuse "ofeoniy two colors. If only one color (e. g., a stopping signal) is desired, or in case use-is made ⁇ oi more j colors (e. g., in c'ase of an intermediate color be# tween red and green), the invention can be ap.,
- a group of gaseous discharge tubes of one color a group of gaseousl discharge tubes of a diierent color, means for tubes are"v apparent to.. v :with a tube of one color alternating with tubes :of vdverent color, a source of energy, means for applying said source of energy to one entire group of tubes and then extinguishing the tubes orsaid groups vone-ata time, and means for tire group of tubes after the last tube of the -rstgroup has been extinguished.
- 4.1In a traffic signal a group of gaseous discharge tubes adapted to emit the same color concentrically mounted, a source of energy, and means for applying said source of energy to the entire group of tubes and then extinguishing the tubes one at a time.
- a group of substantially circular neon gaseous discharge tubes ' adapted to emit the same color of varying sizes concentrically mounted, and means for supplying all oi the dischargev tubes with. electrical energy at.
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Illuminated Signs And Luminous Advertising (AREA)
Description
' TRAFFIC SIGNAL T TN @RF/ffy m, u 2@V Fil?. 13, 1950 2 Sheets-Sheet 2 Patented Aug. 8, 1933 UNITED STATES TRAFFIC SIGNAL Willem Huizinga, Amsterdam, Netherlands Application February 13, 1930, Serial No. 428,146, and in the Netherlands February 13, 1929 claims.
The invention relates to a device for controlling traiiic, more particularly street trailc, by means of one or more colored surfaces, each of which is lighted at intervals. 5 The advantage of such a device is that the signal device itself presents to the trafc an indication of its duration and of the time at which it will change.
The invention relates more particularly to a device by means of which the above object can be realized in a very practical and simple manner, and moreover to a device which from a technical point of view has special advantages.
In the rst place, the invention comprises light- 15. ing a number of colored surfaces and successively extinguishing the sources of light or the groups of sources of light.
The device may comprise a casing suspended or placed upon a pedestal or column, or arranged in any other manner, and a number of sources of light, e. g., electric lamps, arranged in said casing or on said pedestal in such a manner that in case said lamps have been lit a surface or eld of a certain color is visible. These lamps are connect- 25 ed, either separately or in groups, with a switching device that causes the lamps of a particular colored signal to be lit all together and to be extinguished in succession or in successive groups. The device may comprise one or more of such elds 0 of diiierent colors, e. g., for giving a red signal for stopping and a green,one for proceeding.
The switching device may comprise a rotating controller drum, such asf-often used for electrical advertisementand the like. One switching device may be used for a plurality of apparatus. This switching device may be operated manually, electrically, or mechanically.
In order to obtain the desired color effect, use may be made of lamps with'colored glass bulb, or
4 of colored transparent windows (colored glass), or any other device for producing colored light. Neon lights may be utilized advantageously.
In order to get a surface or eld which is colored as equally as possible, it may be advisable to ein-v ploy a screen of ground glass, milk glass, or other transparent light-diffusive glass. Insuch a case, partition walls may be arranged between the sources of light in such a manner that the screen before the extinguished lamps receives no light or verir little light.
' It is further observed that the connection between the sources of light and the switching de vice, and also the switching device itself, may differ very much. The arrangement may be such that all lamps of one color are litat the same time and extinguished one after the other, and likewise groups of lamps may be extinguished in suc-` cession.
Further, the sequence in which the lamps or the groups of lamps are extinguished may vary, and
likewise the manner in which these groups are arranged with respect to each other may be varied.
The invention further relates to an improvement of devices as described hereabove, and in general to devices by means of which traffic may 05 be controlled with the aid of a number of differently colored and alternately appearing lights. In my invention, the colored surfaces appear substantially inthe same plane. f It is evident that the signal controlby thismethod results in smoother and more efficient v traiiic flow, because the driver of the vehicle need only turn his eye towards one certain point. Furthermore, the device lookssmall and simple, which qualities are essential to trame control purposes. This invention may be realized in many ways. Thus, the sources of light for producing two colors (e. g., red and green) may be arranged alternately, and the whole may be set behind a screen of ground glass, milk glass, or other light-diffusive substance. The arrangement should be such that the sources of light for one color do not interfere with those for the other color. v
For the purposes of my invention, neon tubes are especially effective, because they do not needv colored transparent windows. The tubes for both colors, or for a plurality of colors, may be arranged alternately, and the connection may be such that the tubes for producing one color, after being lit, may be extinguished one after the other, whereupon the same operation occurs with the tubes for the other color.
The sources o1' light or the tubes may be arranged in any position with respect to each other,
while the connection, i. e., the sequence in which they are extinguished, may also be different. So the sources of light may for example be placed in concentric circles and the neon tubes may consist of concentric circular tubes. 'Ihe device may work in combination with others for different crossings, and they may also be combined with signal control devices for pedestrians.
Signal devices according to the invention may be provided in a simple manner with means by which in case of need all signals may be placed manually, and/or automatically, for example, in order to pass the fire engines, street cars, or processions, or in case of accident. 'Ihis makes it possible to :dnd a solution for giving some prei- 110 v erence to the street car traic, which manner of controlling may be automatic by closing or interrupting contacts by the street car before the crossing in question.
The invention is more fully described by the drawings, which show one embodiment of a traic control device according to my invention.
Figure 1 is a vertical, schematic section of a signal apparatus according to the invention.
Fig. -2 is a front view of the indication apparatus.
Fig. 3 shows schematically the diagram of connections for switching in and oi'the light sources. v The apparatus comprises a cylindrical casing 1, constructed of durable material such as iron and having a diameter of about 60 centimeters. 'Ihe front of this casing is provided with a glass screen 2 or the like, and the back with a detachable plate 3. At some distance from the casing Wall, a disk 4 is arranged within the casing, said disk being made preferably of multiplex-wood or similar material, containing several perforations or openings and connected with the casing 1 by means of supports 16. Nine neon tubes 5-13 which are circularly bent and nest within one another are mounted on the said wooden disk 4. The odd numbered tubes may radiate a red light, and the even numbered tubes a green light.
The electrodes of said tubes 5--13 pass through the perforations in the wooden disk 4 and thus they are arranged in the space which is accessible by means of the partition wall 3. The high voltage cables 14 connecting the various electrodes with the switching device enter into the said space.
On the front of casing 1, a screen 15 is 'arranged at the top in order to block out daylight and sunlight, so that the light signals will be clearly visible. The complete apparatus may be arranged on a pedestal 17 or against a wall by means of supports or be suspended from cables.
Fig. 3 illustrates the diagram of connection of the device for lighting and extinguishing the neon tubes. The device comprises@1 controller drum 18 for short circuitingand lighting the neon tubes and contacts 19 sliding over said drum. These contacts 19 are connected with the high-voltage cables 14. The controller drum 18 is driven, via a reducing coupling 20, by an electromotor 21 having a predetermined number of revolutions which may be adjustable. The electromotor 21 is connected With the power network by the conductor 22 via fuses 23 and a switch 24. 'Ihe frame of the controller drum, the motor, and the transformers 25 and 26 are connected to ground, as is also one of the contacts 19. The available voltage (of 220 volts, for example) is stepped up by the transformers, which are connected in parallel, to the voltage necessary for lighting the neon tubes (such as 3500 volts) The transformers 25 and 26 are also connected in series with the neon tubes, so that for extinguishing the tubes it is necessary to only short circuit the latter. The advantage of this is that sparking on the controller drum 18 is considerably less than would be the case if the neon tubes were switched oi. In this manner, the life of the controller drum and the corresponding contacts is increased, since said parts are less subject to burning. Moreover, the transformers may be considerably smaller, which is anadvantage when the available space is small.
When the controller drum 18 rotates, the convgroup of contacts in the form of steps.
According to the illustrated embodiment, the controller drum is constructed so that when it is in rotation, at first the ve left contacts 19 cause the short circuit of five tubes (for example, the five tubes giving green light). At this moment, the four right contacts 19 are out of contact with the body 18, so that the other four tubes (e. g., the four tubes giving red light) are in operation. As the drum continues its rotation, the four right contacts are short circuited in succession, so that the corresponding four tubes are extinguished in succession. As soon as the last (inner) tube giving red light has been extinguished, the short circuit on the tubes giving green light is raised because the connection of the ve left contacts is broken and the green tubes will light. After some time, the tubes giving green light are short circuited one after another, and immediately thereupon the tubes gitfing red light begin to light again. At this moment, the drum has performed one revolution.
The transformers should be able to bear the short circuit on the tubes and are calculated so that they can endure the total short circuit.
The controller drum 18 may be constructed so that the duration of the short circuit and that of the lighting of the tubes are mutually and independently adjustable. This may be effected, for example, by constructing the drum of some adjustably arranged rings, the number of which corresponds with the number of tubes or groups of tubes. Moreover, the contacts may be adjustably arranged on the said drum so that any variation is possible.
The present invention also contemplates a signal which has only one light radiating surface, usually red. 1n this case, all of the concentric neon tubes shown in Fig. 2 will radiate red light. After they are all lit, they are gradually extinguished one at a time by means of the controller drum 18. It will be obvious that in this instance the controller drum 18 will diier from that shown in Fig. 3. In Fig. 3, it is necessary to light half the tubes and to extinguish them gradually, and
thereafter to light theether han of the tubes and to extinguish them gradually. The controller drum in this instance should have a continuous In the lowermost position, all the tubes are short circuited so that the traffic signal does not show any light, and the traic moves unhindered. In the next higher position, all the tubes will show a red light so that the traic is stopped. In the next higher position, one of the tubes is short circuited so that the total amount of surface illuminated red becomes smaller. This keeps on until the last or the uppermost position, as shown on the drum 18, when all the tubes are short circuited again, and the light radiating surface has disappeared. In the meantime, of course, the operators of the vehicle have been informed of the duration of the signal by the amount of illuminated surface visible to them.
If it is desired to control the signal manually the controller drum 18 may be manually moved so that'the proper tubes or number of. short circuited.' This can be veryeasily done by havingindexes on the controller drum to enable..
the operator ofthe device to quickly movethe drum into the desired position. Ii itis desired to have the traine controlled by street cars, the
those skilled in the art.
The embodiment as described abovev tended to restrict the invention to tneuse "ofeoniy two colors. If only one color (e. g., a stopping signal) is desired, or in case use-is made `oi more j colors (e. g., in c'ase of an intermediate color be# tween red and green), the invention can be ap.,
plied with the same advantages. i
2. In a traiiic signal, a group of gaseous discharge tubes of one color, a group of gaseousl discharge tubes of a diierent color, means for tubes are"v apparent to.. v :with a tube of one color alternating with tubes :of vdiilerent color, a source of energy, means for applying said source of energy to one entire group of tubes and then extinguishing the tubes orsaid groups vone-ata time, and means for tire group of tubes after the last tube of the -rstgroup has been extinguished.
a different color,l means formounting said groups vapplying vsaid source of energy to another entire lgroup lof tubes when the lastftube of the pre- "ceding grouphas been extinguished.
4.1In a traffic signal, a group of gaseous discharge tubes adapted to emit the same color concentrically mounted, a source of energy, and means for applying said source of energy to the entire group of tubes and then extinguishing the tubes one at a time.
5.' In a trame signal, a group of substantially circular neon gaseous discharge tubes 'adapted to emit the same color of varying sizes concentrically mounted, and means for supplying all oi the dischargev tubes with. electrical energy at.
the same .time and forsuccessively discontinu- 'ing said supplyfot energy to the tubes one at a mounting said groups concentrically with a tubejt voi.' one color alternating with a tube of aditferent color, a source o1 energy. and means for applying'A said source oi energy to one entire -group of tubes and then extinguishing the last said tubes one st a time, the last-named means -applying the source of energy to the second engaseous discharge tubes, each group comprising v
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL1921359X | 1929-02-13 | ||
GB476930A GB347352A (en) | 1930-02-12 | 1930-02-12 | An improved signalling device for controlling street traffic |
Publications (1)
Publication Number | Publication Date |
---|---|
US1921359A true US1921359A (en) | 1933-08-08 |
Family
ID=26239353
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US428146A Expired - Lifetime US1921359A (en) | 1929-02-13 | 1930-02-13 | Traffic signal |
Country Status (3)
Country | Link |
---|---|
US (1) | US1921359A (en) |
DE (1) | DE610883C (en) |
NL (1) | NL24689C (en) |
-
0
- NL NL24689D patent/NL24689C/xx active
-
1930
- 1930-02-13 US US428146A patent/US1921359A/en not_active Expired - Lifetime
- 1930-02-13 DE DE1930610883D patent/DE610883C/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
DE610883C (en) | 1935-03-18 |
NL24689C (en) |
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