|Publication number||US2417443 A|
|Publication date||Mar 18, 1947|
|Filing date||Jul 19, 1941|
|Priority date||Jul 19, 1941|
|Publication number||US 2417443 A, US 2417443A, US-A-2417443, US2417443 A, US2417443A|
|Inventors||Joseph N Paul|
|Original Assignee||Automatic Signal Corp|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (12), Referenced by (5), Classifications (8)|
|External Links: USPTO, USPTO Assignment, Espacenet|
March B, 1947. J, N, `PAUL 2,417,443
' SIGNAL Filedjuly 19, 1941 s sheets-Sheet 1 e `INVENTOR datum/Q ATTORNEY Iwanclll 18, 1947. J, NI PAUL 2,417,443
SIGNAL Filed July 19, 1941 s sheets-sheet 2 l Umar INVENTOR Patented Mar. 18, 1947 UNITED n SIGNAL Joseph N. Paul, Norwalk, Conn., assigner to Automatic Signal Corporation, East Norwalk, Conn., a corporation of Delaware Application July 19, 1941, `Serial No. 403,129
This invention relates to a signal, particularly I to a signal unit of the general type employed for trai-lic signals for road intersections. Signals of similar type are also employed at danger points on highways and at drawbridges, for example. Such traic signals ordinarily have one or more unit assemblies of a lamp, a reflector and a lens. The lens may be colored green, yellow or red for example or may be lettered or provided with some other form of signalling indication, and the lens is illuminated to display its color or indication by means of the lamp.
In one familiar form of traffic signal one of these signal units or an assembly of such units pointing in several directions as desired is used as a cautionary signal with a steady or flashing illumination. In another familiar form a red lens unit and a green lens unit are assembled together to direct traffic to stop and go respectively, and in many cases a third intermediate unit with a yellow lens is included as a signal change indicator, thus providing a three color trailic signal assembly.
As trafc signals, such multiple unit signal assemblies may be employed to give signal indications inone direction only or Several assemblies mayA be grouped to display indications in several directions as required or desired.
The assembly of a lamp socket and reflector and lens is often referred to as the optical assembly of the signal and this assembly is Yplaced in a signal casing for mechanical protection and proper spacing of several assemblies, and for protection against the weather.
The signal casing is provided with a door to hold the lens, and to provide necessary access tothe inside of the casing and the optical assembly to change lamps as they burn out or become ineicient and to clean the reflector and lens on the inside, as well as to work on the wiring for the electric power supply to the lamp. TheV door should be weather-tight but should be adapted to be opened readily since such signals are ordinarily mounted on relatively high posts or over the road for good visibility, and require the use of a tower truck or a ladder by a service man working on the signals. Under such conditions the service man is often able to haver only one hand free to Work on the signal. In many cases where the signal is suspended over the road the service man Working on the signal is exposed to the danger of accident from tramo in the road and Where the signal is suspended over the center of an intersection of tWo or` more roads l it is sometimes necessary to stop all traffic While repairs are being made on the signal.
Since the signals are in use as safety control devices it is important to minimize the time they have to be out of service for vrepair or adjustment and it is desirable therefore to have the casing designed so that the door can be opened quickly and easily under various conditions.`
Thus it is desirable to be able to open or close the door quickly and readily by hand or by a simple prying action of a screw driver, and it is desirable to have the door pressed tightlyagainst gasket material when closed `to protect the inside of the signal from dust and from the Weather.
It will be appreciated that tralic signals are installed in all kinds of climate and that weather conditions are variable over an extremely wide range from time to time at one location and that any one lot of signals manufactured may have signal units delivered to Widely separated locations having widely diiering conditions, so that an important object of signal design is to provide a rugged and' tight construction to meet severe conditions but also a simplified and convenient construction for accessibility of the various parts for service work, particularly inside the signal. l
In various types of signal construction in priorl use with which I am familiar some form of voluntary action by the service man is required to tighten the door after it is closed. A lever wedge ora thumb screw or thumb nut must be operated by hand to tighten the door in two familiar With such forms of construction it is very diiliv cult to obtain suicient or uniform tightness of the door against its gasket consistently in service work on the signalsl and when the usual exposed thread bolt is employed with a thumb nut the thread is frequently coated with paint or otherwise clogged and it is vdiilicult for the service man to determine whether he has tightened the door sufficiently.
These difliculties are increased when gloves are Worn by the service man in cold weather.
It is desirable to provide a strong and tight construction but also to make the door opening and closingl operation simple and to make the door tightening operationf positive and substantially automatic to avoid the possibility of human error in tightening the door insuiciently or unevenly.
- According to the present invention an improved signal is provided with a toggle catch construction for the door giving positive control of door closure pressure With simplified opening and closing operation of the door. In the preferred construction in accordance with the invention the signal is provided with concealed hinges and concealed toggle catches for the door so as to keep these working parts .free from outside exposure and from being clogged with paint in the fre-- quent painting necessary on the outside of signals. The catches employ a toggle device with a high pressure spring so that the door engages its gasket tightly with substantially uniform pres.-
. sure automatically in the closed position, withoutr the need of any tightening adjustment by hand'.
It is a general object of the invention to prof It is another Vobject of the inventicnlto pro-` vide an improved signal` door construction giv ing positive and substantially uniform closure pressure in the closed position. Y A It is also an object of the invention to provide an improved signal casing having a door with concealed hinge and'catch construction.
Itis a further object of the inventionto provide an improved signal casing having aY door with a toggle spring catch. f
An additional object of the invention is vto provide a signal ofthe character described, with a lever member havinga concealed bearing ineinber for opening the door of thersignal. A furtherobject of the invention is to provide an ,improved toggle catchmechanism Yfor a door. The construction of Yone preferred embodiment of theinvention will be better understood in con-l nection with the following description by ref-` erence to the several drawings iii-which:
Figs. l, 2Y and 3 are top, frontv and side views respectively of the signalcasing of asigna] unit.v
Fig. 4 is a partialfvertical sectional View on the lines 4--4V of Fig. 2. v Y
Fig. 5 is an enlarged sectional view of aV form of traffic signal unit showing a sectional View of the improved signal casing as in Fig. 4 but in full section and in connection with parts of the signal unit.
Fig. 6 is a horizontal sectional View of the casing, along the lines 6-5 in Fig. 2, and showing the door and door control in closed position.
Fig. 7 is a sectional view` as in Fig. 6 except that the door and door control are Vshown in open position.Y i 4 Figs. 8 and 9 showl views of the door fromthe right side Vand rear respectively.
Fig. i0 is an enlarged view of the door release lever.
Fig. 11 is a sectional view of the door release lever device along the lines ll-Il of Fig. 2.
Fig. 12 is a rear view of the reflector holder of the signal unit.`
Fig. 13 is a section alonglines I3-i 3 of Fig. 12.
Fig. 14 isa top view'of` the reilector holder.
Considering the signal casing of Figs'. 1, 2y and 3 in greater detail, the main housing and door of the casing are shown in these figures of the `drawings wit-hout the optical unit o f the signal for clearness of illustration. The housing forms the back of the signal unit and the main support the other principal cned or ribbed or both for additional strength if necessary or desired. On the outer surfacesV of the top or bottom sections of such Vassembly the hole may be omitted or plugged or covered with a pipe fitting or ornament as desired, de-
pending upon the means employed for suspending or mounting the signal kfor traine control.
purposes for example. L
In some instances the signal unit may be vused Jfor electrical connections. Y
A door 22 is provided on the front of the signal casing as shown in the front View of Fig. 2. The
door is preferably provided with a circular flange .Edhand lugs 24 on the front for attachment of a sun shield or hood as shown in the sectional sov for the optical assembly. This housing is` ordiview of Fig. 5. The door as shown in Figs. l, 2
and 3 is hinged at the left side of Fig. 2 on upper and lower pins 2S in the housing 28, the upper pin Zappearing in Fig. 1. A lever 2l operating a pivot 28 is provided at the right side of the Y door. This lever is more fully describedbelow. n In the half-section view in Fig; 4 on the vertical center line of the signal casing, along the lines e-i in Fig. 2, the housing 2Q appears partly in and housing in Figs.f Ll'7.v V- This gasket preferably extends along all four edges ofthe door.
Vvasan individual unit and may be back mounted y against an outlet box in a wall or the like and a "hole may be provided if desired in theback to care Four lugs 3l are provided on the inside-of the deer near the corners and one ofthese lugsappears inthe sectional viewof'Fig. 4. A platesz,
appearing in section in Fig. 4; is attacl'ied'to, the
top of the upper lugs 3 l and the spring and toggle cam of the toggle catch are mounted.' en .this plate 32.
The spring 33 and toggle cam 3- appear more K clearly in Figs. 6 and 7. Apin 35.15 fixed in boss 36 in-the top of the housing 2li, and' coop-1 erates with the toggle'camin controlling the'door closing and opening. The pin 35"appears in vertical section in Fig. 4 and in horizontal section in Figs. 6 and 7. Y
Another .pin 3l in a boss 'in the top ofthe housing serves as a bearing for the reiiector holder spring as will be more fully described-be- Iow. 1 Fig. 5 shows a full sectional'view of a signal unit including the signal casing' and the optical unitvassembly and hood. The sectional view is` lustration-but'the remainder of the signal Yunit is shown just as it should appear inthe sectional` viewxas described. A clear lamp' is ordinarily used but for simplicity in the drawingthe lamp filament is not shown.
The Optical unit includes the lens se, the iamp 40, and socket si, and the reflector l2. Therei'lector holder may also he,V considered a part of I, the optical unit and includes'the ring d5, the Spider 46. the gasket 47. the clamps es and screws 5l), and the spring Wire holder 5|.
The door 22 is provided with a recess on the inner side near each of its four edges and the gasket Si) is placed in this recess vto bear against the front edge of the housing when the door is closed. The door is slightly smaller than the housing so that when Signal units are assembled together the edges of adjacent doors will not interfere.' The lens 42 is. set in an inner circular recess in the door and is separated from the door by a gasket 52 which preferably extends over the. edge of the lens for a short distance on both the inner and outer sides. The lens is shown of plain cross-sectional shape for simplicity of illustration although it may have any of varM ious well known shapes depending on the type of light distribution desired outside the signal.
The lens is held in place in the door by the two plates 32, 32 bearing against the inner side of the lens gasket near the upper and` lower edges of the lens. These plates are fastened to the raised portions or bosses 3l on the door, by means of screws 53 through the plates. The upper plate is fastened to the two upper bosses and the lower plate to the two lower bosses. The upper plate 32 and screws 53 can be seen in Fig. 6.
The reflector holder ring 45 also bears against the lens gasket 52 in the closed position of the door.
The toggle catch mechanism for control of the door in accordance with the invention is best illustrated in Figs. 6 and 7 which show the door in closed and open positions respectively. These are sectional views looking down at a horizontal section line 8-6 justrbelow the top of the signal unit in Fig. 2. The plate 32 seen is the upper of the two similar plates on the door. The bearing pin 35, fastened in the top of the housing, is seen only in section.
The toggle cam 34 is positioned by the pin E55 but is free to rotate on this pin. This pin 55 is preferably provided with a shoulder resting against the top of the pate 32 and with another shoulder or head extending over the top of the vtoggle cam 34 so as to allow the cam to rotate on the pin 55 but to restrict the end play of the cam on the pin. The pin may be peened under the plate to hold the pin firm in place. The cam 34 is relatively long and narrow and one end of the cam is bifurcated into the lobes 55 and 'i and the other end is provided with a notch 58. A strong flat type spring 33 nts into the notch 58 at one end and is twisted one quarter turn at its other end Si) to bear on pin Si.
The pin 6l passes through a hole in the end 5B of the spring to key this end of the spring against accidental release but the spring is free to rotate on the pin El. The pin Si is preferably provided with a shoulder bearing against the plate 32 and with a washer lll, and with another shoulder or head overlapping the end of the spring to limit its end play on the pin. The hole in the spring is made large enough to allow passage of the pin shank.
Instead of twisting the end 60 of the spring 33 and providing a hole therein, this end may be formed into a loop to key it 'around the pin Eil, if desired.
The spring 33 is compressed by being bowed as shown in Figs. 6 and '7, and exerts considerable pressure tending to turn the toggle cam counterclockwise with the door in closed position as in Fig. 6. With the door in the open position as in Fig. 7 the spring exerts considerable pressure tending to rotate the toggle cam clockwise. j
A stop pin" 62 is preferably placed in the $2 to limit rotation of the cam 34, particularly in the open position of the door. A small amount of clearance is provided between the stop pin 62 and the cam 34 in the closed position-of the door so that the pressure of the spring 33 willl be transmitted fully through the lobe 56 of the cam against the pin 35 to press the door gasket 3G iirmly against the front edge of the housing 2Q.
The door can be closed simply by pressure against the front. Such pressure brings the lobe El of cam 3.1i into contact with the pin 35 and rotates the cam counterclockwise and thus compressing the spring 33 until the midpoint of maximum compression is reached, after which the spring aids in rotating the cam rapidly to force the door closed with a snap action.
. In opening the door it is pulled away from the housing against the pressure of the spring, since the inner branch or lobe 55 of the bifurcated cam 35i bears against the inner side of pin 35 and thus causes clockwise rotation of the cam and compresses the spring 33.
As soon as the cam passes the center point of maximum spring compression the cam is rapidly rotated further clockwise by pressure of the spring, the cam coming to rest against the stop pin (i2. in the latter position the lobe 5t of the cam is clear of the pin 35 so that the door can be swung freely open.
As shownin the side and rear views of the door in 8 and S a similar toggle catch is provided at the bottom of the door. Thus the two toggle catches, operating on the pins 35 substantially at the middle of the top and bottom of the door, serve to balance the pressure of the door gasket against the front edge of the housing on all sides, providing a floating contact effect under spring pressure.
rihe hole E3 in the plate '32 is made oversize so that there is considerable clearance between the hinge pin 2s and the bearing edge of the plate around the hole in the closed position of the door, thus permitting a free-balancing action of the upper and lower toggle catches.
To provide a convenient means of opening the door the release lever device 2l is mounted on the right side of the door-that is. opposite the hinge as shown in enlarged View in Fig. 10. The lever 2l' is pivoted on the shoulder screw 23 which is fixed in the housing. A rivet pin 84 is fixed in the lever 2l and projects slightly on the inside. This side wall of the housing is mortised as shown at 69 to receive the projection t5 on the door. This projection only7 a thin cross-section so that the mortise is shallow. The lever also requires only a thin cross-section. Y
It will be appreciated that the lever arrangement for opening the door may be omitted if desired and the door may be opened by inserting a screw driver between the door and the housing or between the projection and the edge of the mortise in the housing for leverage for example, and in the latter case a smaller clearance is preferably provided at this point.
in the preferred construction ofthe invention the upper and lower plates 32 bear against the lens gasket 52 for some distance along the inner edge of the lens at the top and bottom of the iens to hold the lens in vposition in the door. Other provisions such as removable lugs might be employed to fasten the lens into the door but in the present preferred embodiment of the invention theplates 32 serve the dual purpose of plate It will be understood that theY reector holder y could be hinged on the door with the spring wire l shape modiied somewhat to accommodate it to thesize and shape of the door, or one or more other well known forms of construction may be substituted orV mounting the reflector either in the housing or on the door without departing from the spirit' of the invention, but in the preferred construction as shown the lens is attached to the door and the reflector is attached to the housing so that only-'the door need be opened to obtain access to the inside of the lens and reiiector and to the lamp. Y
t will also be appreciated that the toggle catch cam and spring assembly could be mounted in the housing the bearing pins 35 mounted on a projection from the door so as to reverse these parts of the toggle catch with respect to the door and housing in place of the preferred construction shown. However the preferred construction has the advantage of making the plate and tog.
gle catch assembly more accessible for assembly and repair of the signal.
A small iange t6 may be provided on the lower end of the lever to provide a grip or bearing for the edge of the ringer in operating the lever toV open the door. A small amount of clearance is provided between fhe rear edge of the projection and the pin t as shown in l1, to allow the lower end of the lever arm to be pulled out beyond the outer edge of the door so that a more convenient grip on the lever may be obtained by the fingers.
The pin is shown in cross-section in Fig. il as this figure shows a sectional view immediately underthe lever. The pivot screw or pin 2S apcross-section 'also in Fig. 11.
in operating the'lever to open the door the lower end or the lever is pulled forward freely a short distance until the pin Ell engages the edge of the projection 65 on the door. Further pull on the-lever isexerted against the spring action of toggle catches by rotation of the toggle cams until the toggle catches are past dead center position. The stroke of the pin Eid against the edge of the projection 65. is long enough to carry the toggle catches beyond dead center.
The plates 32, 32 at the top and bottom of the doorr have a U--shaped sweep @l at the hinge side of the door to provide clearance for the forward edge of the housing when the door is open, thus permitting the door to be swung wide open even though the hinge isinside the housing.
The reflector and reflector-holder of the signal are shown in more detail in Figs. 12, 13 and In the rear and bottom views of Figs. 12 and la respectively the heavy spring wire frame 5l is shown most clearly. At the right side of these iigures the wire is formed into upper and lowerr loops 58 kto bear on the upper and lower reflector hinge pins 3i in the housing. rI'hese loops must be brought nearer together than their free position by deflection of the spring wire to place the loops over the ends of these hinge pins 31, and after being snapped into place the loops are held on the pins only by spring action so that the entire reflector and reiiector holder assembly may be removed readily without tools.
The spring wire is formed in a U-shaped loop and is` held at the four outer ends of the spider 45 by four clamps 5,3 which in turn are fastened to the spider legs by screws 5@ into lugs 'H on A notchedstop 13 `is preferably provided fork the reector holder spring wire 5l inside' the righi; side or thehousing as shown in Figs. 6 and '7 to hold the reflector in its normal operatingv position. The spring wire 5l can be deflected easily` to swing the' reflector holder `out on its hinges if desired. Y
The reiiector 'l2' bears against the offset inner edge on the rear of the ring 45 as shown in Fig. 13'
and is held against this edgelight but firmly by Y the gasket Ill between the spider and the reector. The reflector 'l2 may be of silvered glass or polished aluminum alloy or other material of high reflecting power.
The large hole in the middle of the rear of Y the reflector and spideras shown in the middle oi 12 and Vat the left side of Fig. 13 is provided for the lamp socket as illustrated in Fig., 5. The holes 11i-14 in the back of the spider are provided for screws to hold the lamp socket in place. f
With the loops 68, 68 sprung into place on Athe upper and lower hinge pins ill, 3l' as shown in 5 the completerefiector and reilector holder assembly swings on these hinge pins and can be swung out for access to the back of the lamp receptacle and wiring for example with the door open. Y
' When the door is closed the gasket 52 on the inof the lens presses against the front edgeV of the reflector ring it so as to make a substantially dust tight chamber inside the optical unit; This aids in maintaining the inside lens surface and theV reilector and lamp surfaces at a high it will be understood that the preferred con- Y' and on the door gasket in the closed position',VY
and provides cearance at the door hinges to allow such balancing of Vpressure entirely by' said catches, but that in some conditions of application of the toggle catch construction in signals it may be satisfactory to employ one toggle catch of the present construction opposite the hinge oi the door with reduced hinge clearance.
it will be appreciated that the signal unit employing the concealed hinge and toggle catch construction has been described and illustrated herein particularly as applied to street traffic signals but that the application of such construction is not .limited to such signals. Another example of advantageous application of such 'construction is in railroad signals. Although railroad signals diiier considerably in size and appearance and in optical assembly arrangement they have quite similar service requirements. Y Y
it will be understood that various changes in the'character and arrangement of the parts or substitution of equivalent parts or omission of parts might be made in the constructionof the present signal without departing from the spirit of the invention as defined by the claims.
I claim: I
l. In a signal having a lens, a housing; and a door for the housing, and said door providing a substantially central opening t0 receive said lens, a toggle catch mechanism between said housing and door, and means supporting `said mechanism on the inside ci said door and bearing against said lens to hold said lens in said door.
2. In a signal having a housing and a door for the housing, a toggle catch mechanism between the door housing, said mechanism including a pair of cams, means including a pair of pivots supporting said cams adjacent opposite edges on the inside of said door, a pair oi members mounted on the inside of said housing in position to bear against the respective cams to rotate the cams through an angle about said pivots in closure of the door, and spring means connected with said cams to provide a toggle action in rotation of said cams through said angle and to maintain pressure to hold the door nrmly against the housing when the door is closed.
3. In a signal having a housing and a door for the housing, an improved construction for connection of the door to the housing including the combination of a toggle catch device having a toggle spring cam element and a cooperating bearing pin, one 0n the inside of the door and the other on the inside of the housing adjacent one edge of the door, a second toggle catch device having a similar toggle spring cam element and cooperating bearing pin, one on the inside of the door and the other on the inside of the housing adjacent an opposite edge oi the door, both said devices cooperating to control closing oi said door against said housing and hold said door closed normally under spring pressure against rotation of said cams by said pins, and a pair of hinge pins within said housing closely adjacent to the door and edge of the housing and a pair of cooperating hinge members connected with the inside of said door and formed in an arc to provide clearance for the edge of the signal housing and permit the door to open wide when open but to conceal the hinges entirely inside the housing when the door is closed, said hinge members having considerable clearance from the hinge pins to permit the toggle catch devices to equalize substantially such closing spring pressure, whereby the hinge and catch connection of the door and housing is completely enclosed and closing pressure around the edge of the door is substantially balanced when the door is closed.
4. In a signal having a housing and a door for the housing, a toggle catch mechanism between the door and housing, said mechanism including 'a pair of cams, means including a pair of pivots supporting said cams adjacent opposite edges on the inside of said door, a pair of members mounted on the inside of said housing in position to bear against the respective cams to rotate theV 5. In a signal having a housing and a door or the housing, a plurality oi substantially balanced toggle catch devices between the housing and the door and enclosed within said housing and door when the door is closed, each said toggle catch device including a cam, means including a pivot supporting said cam on the inside of said door, a member mounted in said housing in position to against said cam to rotate the same through an angle in closure of the door, and a. spring connected with said cam to provide a toggle action in rotation of said cam through said angle, cam having one side bifurcated c two lobes, and said bearing member being located between said lobes in the closed position or the door and bearing against the inside edge one lobe tending to rotate the cam against ressure of the toggle spring to hold the door closed against the housing through the spring action.
6. In a signal having an optical assembly in cluding a lamp receptacle, a reector for said receptacle and a lens for covering said receptacie and reiiectcr, and a casing for enclosing the optical assembly, said casing including a housing and a door, and a toggle catch mechanism bet'f'aeen said housing and door a gasket at the edge oi said lens, said toggle catch mechanism including a pair ci plates adjacent opposite edges on the inside of the door and bearing against said gasket to hold the lens in said door, a pair of cams pivotably supported on said plates and hav- Lvio lobes on one side of each cam, and means within the housing and located so as to engage said cams between said lobes to rotate the cams through an angle as said door is closed, and a pair of springs one connected with each cam to provide a toggle spring action as said cams are so rotated through said angle and to maintain pressure tending to rotate said cams against said means in the housing tohold the ydoor iirmly against the housing in the closed position.
JOSEPH N. PAUL.
REFERENCES CITED The following references are of record in the le of this patent:
UNITED STATES PATENTS Number Name Date 1,641,681 Kircher Sept. 6, 1927 1,711,477 Halvorson I Apr. 30, 1929 1,836,845 Halvorson II Dec. 15, 1931 589,418 Conklin Sept. 7, 1897 '755,923 OShaughnessy Mar. 29, 1904 1,592,213 Kleckner July 13, 1926 827,352 Estes July 31, 1906 1,678,137 Douglas July 24, 1928 2,225,217 Hicok Dec. 17, 1940 2,227,655 Levy Jan. 7, 1941 FOREIGN PATENTS Number Country Date 553,587 German (Aus.) June 29, 1932 375,434 French May 14, 1907
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|U.S. Classification||362/374, 362/293, 362/310, 292/78, D10/114.1|