US2223344A

US2223344A - Lamp replacer

Info

Publication number: US2223344A
Application number: US239207A
Authority: US
Inventors: Harold D Grinnell
Original assignee: G C A Manufacturing CO
Current assignee: G C A MANUFACTURING Co
Priority date: 1938-11-07
Filing date: 1938-11-07
Publication date: 1940-12-03
Anticipated expiration: 1957-12-03

Description

Dec. 3, 1940. H D- RINNELL 2223,34@t

LAMP REPLACE R' Filed Nov. 7, 19348 v3 sheets-sheet l.

` ATTORNEYS 3 Sheets-Sheerl 2 Dec. 3, 1940. H. D. GRINNELL LAMP REPLACER Filed Nov. '7, 1938 19A/POL '//wva L LM ATTORNEYS A 3 Sheets-Sheet 5 llllllll. rlllll INVENToR /Zmow 5mm/fu H. D. GRINNELL LAMP REPLACER Filed Nov. 7, 19u38 Dec. 3, 1940.`

Patented Dec. 3, 1940 unire-.o STATES PATENT OFFICE y2,222,34fi

Hamid n. Grinnell. Pittsfield. Mass., assigner to.

The G. Ci. A.` Manufacturing Co.,I lfittsfield,A Mass., a corporation of Massachusetts Y Application-November 7, 1938, Serial No. 239,207

' cciaims. (c1. 294-20) Thisinvention relates-tov apparatus for removing electric light bulbs, particularly those of Alarge size, from sockets ofi the pull type. It is particu`` larly directed to improvements in devices of the general ty-pe shown inV my` prior Patent No. 1,520,946J December 30; 1924, to provide an apparatus which will be capable of handlingbulbs of` larger; size andwith less clearance. between the bulb andthe surrounding reflector or shade. A further object is to prevent injury to the workman in case the bulb should be broken in removal or should come loose beforelbeing properly grasped by the device. A, further object is to provide a mechanism of this type which will be of eX- ceptionally light weight, soA that it may ber of a size to handle bulbsof large sizebut will still not be unwieldy when mounted on the end ofa long pole. A further object is to provide a lamp remover'in. which the opposed grasping iingers'will f beelectrically insulated fromeach other -to avoid accidental short circuting if the fingers contact any part. of the electrical wiring. Additional ob `jects will. appear from the following description and claims.A

Referring to thedrawingsi Fig. 1 is a front elevation of a device constructed in accordance with my invention;

Fig. 2 is a sideelevation thereof;

Fig. 3is' a detail similar `to Fig. 1 but showin the tongsin` open position;

Fig. 4 is a. detail corresponding to Fig. 3` showingthe tongs'beng introduced between the bulb andl the surrounding reflector;

Fig. 5 is a similar detail showingthe tongs grasping the ange of the socket;

Fig. Gisa section on line 6-6 ofFig. l;

Fig. '7 is asection on line 1-1 of Fig. 1;

Fig. 8 isa section on line 8--8 of Fig. 1';

Fig. 9 is a section on line 8-9 of Fig. 1; and

Fig. l is a section on line Ill-I of Fig. 1.

The. device is supported on a squarer tube ll, preferably off sheet aluminumY alloy, embracing and secured to a- Wooden plug i2 (Fig.`9) cylindrical at its lower end and providedwith an 50T relatively longN grasping fingers by vsome mechanism maintaining'said lower ends ata substantially constantdistance apart. Preferably this mechanismconsists'of a sliding frame which will nowv be described.` Freely slidable on theesquare 557 tube. lil is alower frame member Hespecially fingers 3l` are coupled as by links llto the up'- fabricated to secure lightness and strength and4` to vinsulate it from the tube. The frame is composed of two side `plates I8 of sheet insulation, preferably of a fabric base impregnated and. coated with an articial resin which may be one oi the phenolic condensation products. 'Ihese side plates arereenforced throughout their length by strips I9 heid thereto by tubularrivets 20. If the electrical insulation of the fingers isnotl important the strips may be of metal; if insulation is desired they are preferably made of the same material as the plates. Use is repeatedly' made of this type of construction, so that its advantages `may be pointedout now to avoid later repetition.

The insulating sheet itself has strength in its plane, but is flexible as to forces applied transversely. By laminating the sheet with the strip a much stronger plate results. At the same time the insulating properties of the sheet can be preserved by making the reinforcements of the same material; or, if the reenforcements are to be of metal, by terminating them short of any point to which the transmission of current is to be prevented. The platesv are notched at 2l to receivev ears 22 extending from cross plates 23 (Fig. 6) perforated for lightness and forming together with the side plates `a box` structure slidable up and downcnthe tube l l'. On each side the plates i8 arealso reenforced by aluminum cast frames 2t having lugs 25 engaging the ears 22 on` the cross plates'. The castings are secured together by hollow pins 25 secured as in the case of the upper frame to be described. The pins pass freely through a slot 2l in the tube,the slot being suiiioi'en'tly larger than the pins so that the latter never make contact with the metalV tube.

Pivotedfto the ends of the lower frame Il as by hollow pins i are the main. socket grasping -fingersl having notches 32 adjacent their upper ends to receive the flange 33 of a socket 34" of the pull type. These fingers are preferably formed of cast aluminum suitably apertured for lightness, and transversely curved to conform to the socket 3ft and to the electric light bulb 35 r carried by it. Thepins 35j may be anchored in 40 any desired way, but preferably by clips 36 having their ends 3l (Fig. 1) turned over the edges of the strips i3 and the plates I8, and having perforated lugs S8 through which, and the pins 30, cotter y pins 3Q may be passed. The clips serve not only 50 to assist in transmitting stress between the fingers andthe frames but to give a permanent anchorage for the cotter pins.

At an intermediate ypoint of) their length the For this purpose the pair of insulatingstrips t6' per end of the tube I I. For this purpose the tube l I is provided with opposed cap pieces 4I secured together by a hollow pin 42 (Figs. l, 3, and 6) headed over at one end and secured by a cotter pin 43 at the other. The cap pieces are provided with recesses 44 (Fig. 7) at their ends into which t pins 55 of insulating material. The pins pass through holes in the lower ends of the links 4i), and between the links and the cap pieces pass through' strips t of insulation and through side extensions el of the material of the tube II. The insulation serves not only to insulate the links from the tube, but as upper anchorages for certain operating springs as will be pointed out below. The outer ends of the links are pivoted 'to the fingers by hollow pins i8 received in holes in the fingers and secured to the links by Cotter pins (not shown).

The lower frame Il slides freely upon the tube II in order to permit rocking movement of the links Ml. and thus the linkage described determines the path of movement of the fingers 3l but does not actually cause their movement. To operate the fingers under the control of the user there is provided an upper slide 5i! positively controlled in av direction causing opening of the fingers and spring controlled in the direction which causes closing of the ngers. This upper frame is generally similar to the lower frame in construction, having side plates 5I, external reenforcing strips 52 and 53, andv internal reenforcing strips 54 secured as in the former case by hollow rivets (Fig. 8). The frame is provided with cross plates 55 and castings 5G constructed and functioning as in the previous case. The pin 5l by which the two castings are secured together is longer than pin 25 so that it passes through two links 58 pinned at 55 (Fig. 3) to a lever 50 pinned to the tube I I at BI. The pin 6I is preferably insulated from the tube II and ferrule I3 by insulating bushings t I Pin 5l is headed over at one end, and is secured at the other end to one of the links by a cotter pin 52 (Fig. 6). The lever 60 may be provided with a rope (53 (Fig. 3) by which the lever may be rocked downwardly to lower the upper slide by an operator holding the lower end of the pole. IThe plates 5I preferably overlap the strips It in all positions to prevent possible misalignment. f

To raise the upper slide it is connected by tension springs 55 with the upper end of the tube II.

previously referred to are slotted at their ends on their upper edges to receive metal cross pieces 66 (Fig. 5) which are themselves slotted to intert with and thus to retain rm position on the strips. Each cross piece 65 is also notched centrally to receive an end loop of one of the springs 55. A loop on the lower end of the spring is attached to a similar cross piece 6l held in place between ears 68 (Figs. 3 and 8) formed from the internal reenforcing strips 5l. By the force of the spring the upper slide is urged upwardly, in

the opposite direction from that given by pulling on the rope 53, operating through the mechanism now to .be described to cause closure of the fingers. i

On the upper portion of the upper slide 50 opposing side plates are joined by hollow rivets lil (Fig. i0) surrounded freely by rollers l E, preferably ofY insulating material, the rivets preferablyl being held'by clips l2 similar to the clips 36 previously described. As the frame reciprocates the rollersrideuponl a cam I3 formed on the outer surface of. thev fingers and embodying a curved portion 'III and a straight locking portion 15 having an angularity sufficiently small to prevent any outward movement of the fingers. The coaction of the rollers and the cams forces the fingers inwardly when the springs 65 draw the upper frame upwardly, the links 40 rocking and the lower slide I'I rising to permit this motion. When the lever 6I] is rocked to lower the upper frame, the fingers tend to sink by their own weight and to carry the lower frame down with them. In this downward movement the resulting swinging ofthe links 40 carries the ngers outwardly. If for any reason the lower slide should stick, it will be moved downwardly by the positive contact of the box-like structure of the two frames where they surround the tube II.

In order to prevent a bulb, or the fragments of a shattered bulb, from dropping, a fabric bag is ysecured to a frame 8| shown as consisting of a metal base 82 with upstanding sides and light, flexible sides 83 preferably of the same insulating material as was used'in the construction of the sliding frames. The bag receives the sides of the bulb practically completely, and prevents its dropping by its premature loosening from the socket; and also prevents fragments of a bulb from dropping if Ait is accidentally shattered.

Referring particularly to Figs. 4 and 5, it will. v

be seen that while the device is useful in extracting bulbs and sockets of any pull type, it is particularly useful in cases where the external reector or shade 85 is spaced very closely to the bulb, so that the lingers have only a slight clearance in which to enter and then to shift their position in order to grasp the socket fiange. In the case for which the device of the present invention was originally designed this clearance was only'%". At the same time the larger sized bulbs have a ratio between maximumv bulb diametel' and socket diameter much higher than is true with smaller sizes. This means that the fingers not only have to pass through a small aperture, but have to tilt sufficiently to grasp the socket while leading their intermediate portions around the bulb in close proximity thereto, A parallel motion such as shown in my Patent No. 1,520,946 will not produce this double effect with as little clearance as is necessary in the conditions for which the present invention was designed.

Inthe present instance the lower ends of the clamping fingers Aare carried on vertically reciprocating pivots, although it is apparent that a pair of links pivoted to the tube I I would furnish support in somewhat the same manner. The motion given to the 'fingers is thus'almost entirely one of tilting as may be controlled by the links til'. Suitable variations in this motion for special conditions may beA controlled by changing the lengths and pivotal points of the links; as suggested above by substituting a supporting linkage for the lower sliding frame; and by changing the lengths` of the lingers themselves.

I claim:

l. In a device for removing lamps from sockets, a pair of grasping fingers having free grasping ends, a pole-carried support, links connected to said support and tri-intermediate points on the fingers and divergingin a direction towards the freeY ends of the fingers, av slide mounted on saidA support, pivots connecting said slide with the other ends of the fingers, a second slide on the support engageable with the fingers intermediatetheir lengths, `the contacting surfaces of said second slide and said fingers being shaped for cam action, spring means for Vshifting the second slide on the support in a direction to cause said cam action to close the fingers, and manually operable mechanism for causing movement of the second slide in the opposite direction, said contacting surfaces being formed at such an angle as `to be irreversible when the fingers are in grasping position.

2. A pole-supported lamp removal device for lamps of the pull-socket type, having socketengaging iingers and actuating means therefor, in combination with a flexible bag and means for positioning the bag in open condition between the fingers.

3. A pole-supported lamp removal device for lamps of the pull-socket type, having socketengaging fingers and actuating means therefor, in combination with a iiexible bag and a iiexible bag support carried by the pole in position to hold the bag in open condition between the fingers.

4'. A lamp removal device comprising a support, opposed lingers having free ends shaped to conform to and grasp a portion of the lamp to be removed, a slide movable lengthwise on the support and having pivotal connection with the fingers at the opposite ends thereof, an intermediate slide movable lengthwise on the support and having cam connection with intermediate portions of the fingers, links connecting an intermediate portion of each nger With the support, and means for moving the intermediate support in one direction to` cause operation of said cam connections or in the other direction to make contact with the rst support to cause the fingers to be separated by outward swinging of said links.

5. A lamp removal device comprising a support, opposed fingers having free ends shaped to conform to and grasp a portion of the lamp to be removed, a'y slide movable lengthwise on the support and having pivotal connection with the fingers at the opposite ends thereof, an intermediate slide movable lengthwise on the support `and having cam connection with an intermediate portion of each finger, each of said frames comprising a box-like structure of sheetv insulation surrounding the guide and finger-engaging portions of said sheet insulation extending laterally from said `box-like structure, and reenforcing strips riveted at intervals to said sheet material, linksv connecting an intermediate portion of each finger with the support, and means for moving the intermediate support in one direction to cause operation of the cam connections or in the other direction to make contact with the rst support to cause the fingers to be separated by outward swinging of said links.

6. A lamp removal device 'comprising opposed fingers having free end-s shaped to conform to and grasp a portion of the lamp to be removed, three mutually movable members, pivotal connections between the opposite ends of the ngers and one of the members, links connecting an intermediate portion of each iinger with a second member, locking cam connections between the fingers and the third member, and means for causing relative movement between the members.

HAROLD D. GRINNELL.