CA1083108A - Rotating warning lamp - Google Patents
Rotating warning lampInfo
- Publication number
- CA1083108A CA1083108A CA262,673A CA262673A CA1083108A CA 1083108 A CA1083108 A CA 1083108A CA 262673 A CA262673 A CA 262673A CA 1083108 A CA1083108 A CA 1083108A
- Authority
- CA
- Canada
- Prior art keywords
- shaft
- motor
- base
- bulbs
- providing
- 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
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60Q—ARRANGEMENT OF SIGNALLING OR LIGHTING DEVICES, THE MOUNTING OR SUPPORTING THEREOF OR CIRCUITS THEREFOR, FOR VEHICLES IN GENERAL
- B60Q1/00—Arrangement of optical signalling or lighting devices, the mounting or supporting thereof or circuits therefor
- B60Q1/26—Arrangement of optical signalling or lighting devices, the mounting or supporting thereof or circuits therefor the devices being primarily intended to indicate the vehicle, or parts thereof, or to give signals, to other traffic
- B60Q1/2611—Indicating devices mounted on the roof of the vehicle
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)
Abstract
ROTATING WARNING LAMP
Abstract A rotating lamp comprising a lamp base and an electric motor mounted on the lamp base. The electric motor drives a hollow shaft on which the lamps are mounted. A conductive rod extends through the shaft and is electrically isolated from the shaft. The lamps which are mounted on the shaft are electrically inter-connected between the rod and the shaft. The housing of the electric motor is electrically isolated from the base. Brush means provide electrical continuity between the power source and the rod. Additional brush means provide electrical continuity between the shaft and the base.
- i -
Abstract A rotating lamp comprising a lamp base and an electric motor mounted on the lamp base. The electric motor drives a hollow shaft on which the lamps are mounted. A conductive rod extends through the shaft and is electrically isolated from the shaft. The lamps which are mounted on the shaft are electrically inter-connected between the rod and the shaft. The housing of the electric motor is electrically isolated from the base. Brush means provide electrical continuity between the power source and the rod. Additional brush means provide electrical continuity between the shaft and the base.
- i -
Description
This invention relates to rotating warning lamps and specifically to improvements in their application in heavy-duty construction and industrial machinery.
Backqround of the Invention Devices used to warn approaching motoxists of a hazardous condition are generally constructed in a manner to facilitate the rendering of visual signals -over a complete field of 360 degrees. Consequently, such devices generally comprise a plurality of sealed beam lamps rotating about a vertical axis.
The utilization of such devices on heavy equipment, such as snow plows, road graders and the like, has generally resulted in severe problems due to reductions to normal life-expectancy. Experimen-tation has determined that these abnormally premature failures are caused by the mechanical exaggeration of electrical erosion at current carrying bearing or journal points. Normal applications of such devices .
use the rotating shaft of the device to carry current to the sealed beam bulbs. This results in an appre-ciable degree of arcing activity between the shaft and the journal bushings. In the presence of severe vibration loads, the constant motion serves to ~ ~
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...,, . . . . . ~ . . : . , :
. - . : ,,: :, . , ....... :., . . ~ : .: .... . .
. . .
~ -10831~
- significantly ampllfy the arcin~ factor, giving rise to a spark-erosion conditionO As the shaft rotates about its axis, circumferentially encompassed by the journal bushing, the effect of normal friction is grossly in- !
creased by the combined factors of increased shaft and journal temperatures and the erosion generated particles from the generally soft journal bushing. The direct result is the formation of an abrasive lapping compound which rapidly deteriorates the basic dimensional accu-racies of fit initially established. As the clearance ¦-between the components increases, the arcing increases ¦
in severity and the -Eactors causing failure are aggravated.
Therefore, the invention is directed to a rotating warning lamp wherein the lamp current does not pass through the shaft-journal interconnection an*, preferably, the motor 1 ~
current also does not pass throuyh the shaft-journal inter- ~ ;
i . .
connection.
S~MMARY OF THE INVENTION ~ -In accordance with one aspect of this invention I -there is provided in a rotating lamp, a base, a motor including a housing and a wlnding, means for mounting said motor on said base '!
such that said housing is electrically isolated from said base, a shaft extending u~wardly from said motor a plurality of bulbs, .
means for mounting said bulbs on said shaft, said shaft being hollow, electrically conductive means extending ~hrough said shaft and rotatable therewith, r~ ~
.... ~ .
.. ~ ' ' ' : ~ ,- . : .
. .
means for electrically insulating said shaft~
from said electrically conductive means, means for providing an electrical connec~ion from said electrically conductive means to said bulbs, means for providing an electrical connection .
from a source to said electrically conductive means, means for providing a grounding from said .
bulbs to said housing, means for providing an electrical connection I ~.
rom a source to said motor.
In accordance with another aspect of this inven- : .
tion there is provided in a ro~ating lamp, a base, a motor including a housing and a winding, means for mounting said motor on said base. .
such that said housing is electrically isolated from said base, .
. a shaft extending upwardly from said motor~ .
: a plurality of bulbs, means for mounting said bulbs on said shaft, said shaft being hollow, ¦~
a rod bf electrically conductive material extending ~hrough said shaft and rotatable therewith, ,~ , i~ , ~ 083~
means for electrically insulating said shaft from said rod, means for providing an electrical connection from said rod to said bulbs, ~ :
means for providing an electrical connection rom a source to said rod, ~:
means for providing a grounding from said :
bulbs ~o said housing, .. means *or pxoviding an electrical connection ~ ;
*rom a source to said motorO
.
Description of the Drawinqs ¦~
, ' ' '~ ' .
~igO 1 is a perspective view of a rotating warning lamp embodying the invention.
Fig. 2 is a vertical sectional view thereof. ~ .
Fig. 3 is a ragmentary sectional viewO
Fig. 4 is a wiring diagram of the lamp. i :
.
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~ .
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.
~L~133~
Description Referring to the drawings, the rotating warning lamp 11 comprises a base having a transverse top wall 12a, an electric motor assembly 30 mounted securely to the underside of the top wall 12a, and a rotatable vertical shaft 13 extending upwardly from the gear box section 14 of the motor assemhly 30. A plurality of sealed beam lamps 15 are mounted on the shaft 13 by an upper bracket 16b and a lower bracket 16a. The assembly of lamps 15 and brackets 16a, 16b is maintained in position on the shaft 13 by a retaining ring 19 at the bottom which snaps into a groove in shaft 13 and a nut 18 at the top (Figs. 2 and 3).
Shaft 13 is hollow and has a through-bore 13a. An insulating tube 20 surrounds an electrically-conductive rod 21 which passes through shaft 13. The rod 21 is electrically connected to the sealed beam lamps through wires 37, 38 made to positive contacts 37a, 38a of the sealed beams 15. A nut 27a is threaded on rod 21 to retain the end of wire 37 against insulating washer 27b and complete the circuit to rod 21. The lower end of the rod 21 has an annular contact 22 held in place by a nut 27. Contact 22 passes through a clearance hole in plate 26 and is electrical~y isolated from the shaft . ' ,' ' , , . .. . . . . : .. . ... .. .. . .
~L~83~
13 by the shouldered insulating bushing 17. Plate 26 is rigidly mounted onto the electric motor assembly 30 by bolts 25. It is electrically insulated therefrom by insulating wash~ers 28, 29 which encircle bolts 25. srush assembly 23 which is mounted on plate 26 includes a brush 24 yieldingly urged against contact 22 (Fig. 2). A
terminal 35 is connected to the brush assembly 23 and a lead 35a provides a circuit between the supply system, noted as a battery, and the sealed beam lamps 15. The 10 gear box 14 includes shaft journals 60a, 60b. Shaft 13 is mounted through ~ournals 60a, 60b. Gear 14a in gear box 14, part of motor assembly 30, is mounted on shaft 13. The motor assembly 30 and gear box 14 are mounted on top wall 12a of the base 12 by bolts 51 which pass .. . :. .
through electrically insulating washers 52, 52a. Washers 52, 52a insulate top wall 12a, which is electrically connected to circuit ground, from motor assembly 30 including gear box 14 and shaft journals 60a, 60b.
A contact member 45 spaced from top wall 12a 20 is held in place on shaft 13 by a set screw 47 and a -brush assembly 43 on wall 12a yieldingly urges a brush 44 against contact member 45 to provide eléctrical ; ;
continuity between the shaft 13 and the-top wall 12a.
The brush assembly 43 is fastened to the top wall 12a by suitable means, such as on,e or more tubular rivets 62 and the brush lead 61 is clamped therebetween.
~83~8 As shown in Fig. 2, the sealed beam contacts 14b and 14c are interconnected by a wire 38b and a wire 38c extends from contact 14b therefrom to lower support bracket 16a. The lower support bracket 16a is, in turn, electrically connected through shaft 13 to contact 45.
The lamp circuit current passes between the shaft 13 and top wall 12a only by means of the brush assembly 43.
Thus, the shaft-journal interconnection is electrically inert. The source of power such as a battery is connected `
to the motor 31 of motor assembly 30 by a lead 64. A
ground lead 63 from the motor extends to base 12a. ;
The circuit thus formed is shown in Fig. 4 with corresponding contact points identified in Fig. 2.
Current from the battery is supplied to point Bl at j -;
brush 24, to point B2 (annular contact 22), then to point B3 (rod 21) to points B4, B5, B6 (wire 37 and bulbs L1, L2), points A5, A4 (contacts 14c, 14b), point A3 (bracket 16a), point A2 (annular contact 45), point Al (brush 44) to point A7 (housing 12a) which is grounded. Current is supplied to the winding of motor 31 from contact B7, through the winding of the motor to ground via the contact A6. If four bulbs are used instead of two, added contacts Bg, Blo and ; -Alo, A11 are provided for supplying current to bulbs L3, L4.
.' ~'','''"."' .
, .~ . ... . . . .
', , ', ' ', , ' . ': ' ' ' , ' ' ' ', 33~
Although, in accordance with the invention, the lamp current is preferably prevented from passing through the journals by electrically insulating the motor housing from the grounded base, in the light of the disclosure, it will be apparent to persons skilled in the art that satisfactory results can be achieved by making the motor housing, journals or ~:
hollow shaft of non-conductive material; it being understood that if the shaft is made of non-conductive material, a circuit must be completed through other means such as wires. :;:
.
Backqround of the Invention Devices used to warn approaching motoxists of a hazardous condition are generally constructed in a manner to facilitate the rendering of visual signals -over a complete field of 360 degrees. Consequently, such devices generally comprise a plurality of sealed beam lamps rotating about a vertical axis.
The utilization of such devices on heavy equipment, such as snow plows, road graders and the like, has generally resulted in severe problems due to reductions to normal life-expectancy. Experimen-tation has determined that these abnormally premature failures are caused by the mechanical exaggeration of electrical erosion at current carrying bearing or journal points. Normal applications of such devices .
use the rotating shaft of the device to carry current to the sealed beam bulbs. This results in an appre-ciable degree of arcing activity between the shaft and the journal bushings. In the presence of severe vibration loads, the constant motion serves to ~ ~
:~;' ~ ':
~' ;' , .~ : ' .
...,, . . . . . ~ . . : . , :
. - . : ,,: :, . , ....... :., . . ~ : .: .... . .
. . .
~ -10831~
- significantly ampllfy the arcin~ factor, giving rise to a spark-erosion conditionO As the shaft rotates about its axis, circumferentially encompassed by the journal bushing, the effect of normal friction is grossly in- !
creased by the combined factors of increased shaft and journal temperatures and the erosion generated particles from the generally soft journal bushing. The direct result is the formation of an abrasive lapping compound which rapidly deteriorates the basic dimensional accu-racies of fit initially established. As the clearance ¦-between the components increases, the arcing increases ¦
in severity and the -Eactors causing failure are aggravated.
Therefore, the invention is directed to a rotating warning lamp wherein the lamp current does not pass through the shaft-journal interconnection an*, preferably, the motor 1 ~
current also does not pass throuyh the shaft-journal inter- ~ ;
i . .
connection.
S~MMARY OF THE INVENTION ~ -In accordance with one aspect of this invention I -there is provided in a rotating lamp, a base, a motor including a housing and a wlnding, means for mounting said motor on said base '!
such that said housing is electrically isolated from said base, a shaft extending u~wardly from said motor a plurality of bulbs, .
means for mounting said bulbs on said shaft, said shaft being hollow, electrically conductive means extending ~hrough said shaft and rotatable therewith, r~ ~
.... ~ .
.. ~ ' ' ' : ~ ,- . : .
. .
means for electrically insulating said shaft~
from said electrically conductive means, means for providing an electrical connec~ion from said electrically conductive means to said bulbs, means for providing an electrical connection .
from a source to said electrically conductive means, means for providing a grounding from said .
bulbs to said housing, means for providing an electrical connection I ~.
rom a source to said motor.
In accordance with another aspect of this inven- : .
tion there is provided in a ro~ating lamp, a base, a motor including a housing and a winding, means for mounting said motor on said base. .
such that said housing is electrically isolated from said base, .
. a shaft extending upwardly from said motor~ .
: a plurality of bulbs, means for mounting said bulbs on said shaft, said shaft being hollow, ¦~
a rod bf electrically conductive material extending ~hrough said shaft and rotatable therewith, ,~ , i~ , ~ 083~
means for electrically insulating said shaft from said rod, means for providing an electrical connection from said rod to said bulbs, ~ :
means for providing an electrical connection rom a source to said rod, ~:
means for providing a grounding from said :
bulbs ~o said housing, .. means *or pxoviding an electrical connection ~ ;
*rom a source to said motorO
.
Description of the Drawinqs ¦~
, ' ' '~ ' .
~igO 1 is a perspective view of a rotating warning lamp embodying the invention.
Fig. 2 is a vertical sectional view thereof. ~ .
Fig. 3 is a ragmentary sectional viewO
Fig. 4 is a wiring diagram of the lamp. i :
.
'' . . ~
i,. :.
t~:
, - . ' -:
~ .
-3a- ; :
.. ~. ' ' . .
' -( ~ , , ,. : , '' ' ' ' ~ , ', ' ;
.
~L~133~
Description Referring to the drawings, the rotating warning lamp 11 comprises a base having a transverse top wall 12a, an electric motor assembly 30 mounted securely to the underside of the top wall 12a, and a rotatable vertical shaft 13 extending upwardly from the gear box section 14 of the motor assemhly 30. A plurality of sealed beam lamps 15 are mounted on the shaft 13 by an upper bracket 16b and a lower bracket 16a. The assembly of lamps 15 and brackets 16a, 16b is maintained in position on the shaft 13 by a retaining ring 19 at the bottom which snaps into a groove in shaft 13 and a nut 18 at the top (Figs. 2 and 3).
Shaft 13 is hollow and has a through-bore 13a. An insulating tube 20 surrounds an electrically-conductive rod 21 which passes through shaft 13. The rod 21 is electrically connected to the sealed beam lamps through wires 37, 38 made to positive contacts 37a, 38a of the sealed beams 15. A nut 27a is threaded on rod 21 to retain the end of wire 37 against insulating washer 27b and complete the circuit to rod 21. The lower end of the rod 21 has an annular contact 22 held in place by a nut 27. Contact 22 passes through a clearance hole in plate 26 and is electrical~y isolated from the shaft . ' ,' ' , , . .. . . . . : .. . ... .. .. . .
~L~83~
13 by the shouldered insulating bushing 17. Plate 26 is rigidly mounted onto the electric motor assembly 30 by bolts 25. It is electrically insulated therefrom by insulating wash~ers 28, 29 which encircle bolts 25. srush assembly 23 which is mounted on plate 26 includes a brush 24 yieldingly urged against contact 22 (Fig. 2). A
terminal 35 is connected to the brush assembly 23 and a lead 35a provides a circuit between the supply system, noted as a battery, and the sealed beam lamps 15. The 10 gear box 14 includes shaft journals 60a, 60b. Shaft 13 is mounted through ~ournals 60a, 60b. Gear 14a in gear box 14, part of motor assembly 30, is mounted on shaft 13. The motor assembly 30 and gear box 14 are mounted on top wall 12a of the base 12 by bolts 51 which pass .. . :. .
through electrically insulating washers 52, 52a. Washers 52, 52a insulate top wall 12a, which is electrically connected to circuit ground, from motor assembly 30 including gear box 14 and shaft journals 60a, 60b.
A contact member 45 spaced from top wall 12a 20 is held in place on shaft 13 by a set screw 47 and a -brush assembly 43 on wall 12a yieldingly urges a brush 44 against contact member 45 to provide eléctrical ; ;
continuity between the shaft 13 and the-top wall 12a.
The brush assembly 43 is fastened to the top wall 12a by suitable means, such as on,e or more tubular rivets 62 and the brush lead 61 is clamped therebetween.
~83~8 As shown in Fig. 2, the sealed beam contacts 14b and 14c are interconnected by a wire 38b and a wire 38c extends from contact 14b therefrom to lower support bracket 16a. The lower support bracket 16a is, in turn, electrically connected through shaft 13 to contact 45.
The lamp circuit current passes between the shaft 13 and top wall 12a only by means of the brush assembly 43.
Thus, the shaft-journal interconnection is electrically inert. The source of power such as a battery is connected `
to the motor 31 of motor assembly 30 by a lead 64. A
ground lead 63 from the motor extends to base 12a. ;
The circuit thus formed is shown in Fig. 4 with corresponding contact points identified in Fig. 2.
Current from the battery is supplied to point Bl at j -;
brush 24, to point B2 (annular contact 22), then to point B3 (rod 21) to points B4, B5, B6 (wire 37 and bulbs L1, L2), points A5, A4 (contacts 14c, 14b), point A3 (bracket 16a), point A2 (annular contact 45), point Al (brush 44) to point A7 (housing 12a) which is grounded. Current is supplied to the winding of motor 31 from contact B7, through the winding of the motor to ground via the contact A6. If four bulbs are used instead of two, added contacts Bg, Blo and ; -Alo, A11 are provided for supplying current to bulbs L3, L4.
.' ~'','''"."' .
, .~ . ... . . . .
', , ', ' ', , ' . ': ' ' ' , ' ' ' ', 33~
Although, in accordance with the invention, the lamp current is preferably prevented from passing through the journals by electrically insulating the motor housing from the grounded base, in the light of the disclosure, it will be apparent to persons skilled in the art that satisfactory results can be achieved by making the motor housing, journals or ~:
hollow shaft of non-conductive material; it being understood that if the shaft is made of non-conductive material, a circuit must be completed through other means such as wires. :;:
.
Claims
The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
1.
In a rotating lamp, a base, a motor including a housing and a winding, means for mounting said motor on said base such that said housing is electrically isolated from said base, a shaft extending upwardly from said motor, a plurality of bulbs, means for mounting said bulbs on said shaft, said shaft being hollow, electrically conductive means extending through said shaft and rotatable therewith, means for electrically insulating said shaft from said electrically conductive means, means for providing an electrical connection from said electrically conductive means to said bulbs, means for providing an electrical connection from a source to said electrically conductive means, means for providing a grounding from said bulbs to said housing, means for providing an electrical connection from a source to said motor.
2.
The rotating lamp set forth in claim 2 including means for grounding said winding of said motor.
3.
The rotating lamp set forth in claim 1 wherein said base is made of electrically conductive material, means for mounting said motor housing on said lamp base and driving said shaft such that said motor housing is electrically insulated from said base.
4.
In a rotating lamp, a base, a motor including a housing and a winding, means for mounting said motor on said base such that said housing is electrically isolated from said base, a shaft extending upwardly from said motor, a plurality of bulbs, means for mounting said bulbs on said shaft, said shaft being hollow, a rod of electrically conductive material extending through said shaft and rotatable therewith, means for electrically insulating said shaft from said rod, means for providing an electrical connection from said rod to said bulbs, means for providing an electrical connection from a source to said rod, means for providing a grounding from said bulbs to said housing, means for providing an electrical connection from a source to said motor.
5.
The rotating lamp set forth in claim 4 including means for grounding said winding of said motor.
6.
The rotating lamp set forth in claim 4 wherein said means providing an electrical connection from said source to said rod comprises a brush extending radially and an annular contact on said rod engaged by said brush.
7.
The rotating lamp set forth in claim 4 wherein said means providing a ground for said bulbs comprises a brush on said base and extending radially and an annular contact on said shaft engaged by said brush.
1.
In a rotating lamp, a base, a motor including a housing and a winding, means for mounting said motor on said base such that said housing is electrically isolated from said base, a shaft extending upwardly from said motor, a plurality of bulbs, means for mounting said bulbs on said shaft, said shaft being hollow, electrically conductive means extending through said shaft and rotatable therewith, means for electrically insulating said shaft from said electrically conductive means, means for providing an electrical connection from said electrically conductive means to said bulbs, means for providing an electrical connection from a source to said electrically conductive means, means for providing a grounding from said bulbs to said housing, means for providing an electrical connection from a source to said motor.
2.
The rotating lamp set forth in claim 2 including means for grounding said winding of said motor.
3.
The rotating lamp set forth in claim 1 wherein said base is made of electrically conductive material, means for mounting said motor housing on said lamp base and driving said shaft such that said motor housing is electrically insulated from said base.
4.
In a rotating lamp, a base, a motor including a housing and a winding, means for mounting said motor on said base such that said housing is electrically isolated from said base, a shaft extending upwardly from said motor, a plurality of bulbs, means for mounting said bulbs on said shaft, said shaft being hollow, a rod of electrically conductive material extending through said shaft and rotatable therewith, means for electrically insulating said shaft from said rod, means for providing an electrical connection from said rod to said bulbs, means for providing an electrical connection from a source to said rod, means for providing a grounding from said bulbs to said housing, means for providing an electrical connection from a source to said motor.
5.
The rotating lamp set forth in claim 4 including means for grounding said winding of said motor.
6.
The rotating lamp set forth in claim 4 wherein said means providing an electrical connection from said source to said rod comprises a brush extending radially and an annular contact on said rod engaged by said brush.
7.
The rotating lamp set forth in claim 4 wherein said means providing a ground for said bulbs comprises a brush on said base and extending radially and an annular contact on said shaft engaged by said brush.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA262,673A CA1083108A (en) | 1976-10-04 | 1976-10-04 | Rotating warning lamp |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA262,673A CA1083108A (en) | 1976-10-04 | 1976-10-04 | Rotating warning lamp |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1083108A true CA1083108A (en) | 1980-08-05 |
Family
ID=4106999
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA262,673A Expired CA1083108A (en) | 1976-10-04 | 1976-10-04 | Rotating warning lamp |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1083108A (en) |
-
1976
- 1976-10-04 CA CA262,673A patent/CA1083108A/en not_active Expired
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |