US2178526A - Resilient support for lighting attachments - Google Patents

Description

Oct. 31', 1939. R E. voM LEHN 2,178.526

RESILIENT SUPPORT FOR LIGHTING ATTACHMENTS Filed April 1o, 1937 En@ =T 4gli 1Q-#wur Reinhold E'. UomLehn WN@ SM,

Patented Oct. 31, 1939 ""NTED STATES RESILIENT SUPPORT FOR. LIGHTING ATTACHMENTS Application April 10, 1937, Serial No. 136,059

2 Claims.

This invention relates to lighting attachments for sewing machines and more particularly to an improvement in the supporting means for the lighting attachment forming the subject of my U. S. Patent No. 2,067,868, issued Jan, 12, 1937.

In practice, it has been found that, in certain sewing machines, high speeds of operation set up vibrations therein which, when transmitted to a lighting attachment mounted upon the machine, materially shorten the life of the lamp bulb. With the particular type of lighting attachment disclosed herein, a lamp bulb of the low-voltage automobile type is preferred; the v usual soft contacts thereof engaging the ends of comparatively hard spring-biased pins mounted in the lamp-socket. Severe vibrations, when transmitted to the lighting attachment, cause the spring-biased pins to hammer small cavities into the contacts and, in a short time, these cavities 2g become of such depth that the pins no longer engage the contacts. In these extreme cases frequent renewal of the lamp bulb is required.

It is therefore one of the objects of the present invention to provide a lighting attachment with a g5" supporting means designed to dampen and absorb destructive vibrations and thereby prevent them from being transmitted to the lamp socket.

Another object of the present invention is to provide a vibration-absorbing support for a lighting attachment which will function eiciently and which will, at the same time, be simple in construction and easy to manufacture and assemble.

With the above and other objects in view, as

Will hereinafter appear, the invention comprises the devices, combinations and arrangements of parts hereinafter described in connection with the accompanying drawing which illustrates a preferred embodiment of the invention, and in which:

Fig. l is a perspective View of a sewing machine equipped with a lighting device embodying the invention.

Fig. 2 represents an enlarged vertical sectional view of the supporting means for the lighting attachment taken substantially along line 2 2, Fig 1.

Fig. 3 represents an enlarged view partly in section and partly in elevation taken, substantially along line 3 3, Fig, 2, showing the details of construction of the improved resilient supporting means.

Fig. 4 is an enlarged perspective view of the two-part sleeve which embraces the cylindrical attachment-supporting arm.

The invention is shown as applied to a sewing machine having a bed i from which rises a standard 2 of the overhanging bracket-arm 3 terminating in a head ll which supports the usual reciprocatory needle-bar 5 and presser-bar 6 carrying, respectively, the needle 'l and presserfoot 8. Below the bed are mounted the usual loop-taker 8 and feeding mechanism (not shown). The presser-bar and foot may be lifted,

for the insertion or removal of work, by means of 10:

the regular hand-operated presser-lifter I or by means of the treadle-controlled presser-lifter lever Il which is fulcrumed on a presser-lifter stud-screw I2 carried by the bracket-arm 3.

The presser-lifter stud-screw l2 is formed with 15f a head I3 from which projects a portion i4 on which is svidveled the vertically disposed arm l5 of a right-angle bracket i5, i5. In order to hold the right-angle bracket l5, IS in adjusted position on the stud-screw l2, there is provided a 20 dished spring-washer il which frictionally bears upon the arm l5 and holds the latter snugly in Contact with the washer i8 held in place by the nut I9.

Swiveled upon the horizontal arm I6 of the 25 angle-bracket i5, IG is the horizontal arm 20 of a second angle-bracket 2t, 2l. The angle-bracket arms I6 and 20 are preferably secured together by a shouldered stud-screw 22 under the head of which is disposed a dished spring-washer 23. 30 The nut 2t holds the stud-screw 22 tightly seated against the angle-bracket-arm 20,

The angle-bracket-arm 2l has a semi-cylindrically bent terminal portion 25 constituting one half of the casing 25, 2t, the other similarly bent 35 portion 25 of which is formed at its lower edge with a shank-plate 2i. These two casing members are preferably secured together by two fastening screws 28. Housed within the casing 25,

26 are two oppositely disposed helically-coiled 40 beehive springs 29, Sli the outer or larger ends of which abut against the inturned flanges 3l, 32 formed on the ends of the casing. The smaller or inner ends of the springs are coiled about the end-portions of an elongated collar 33 formed 45 centrally with an enlarged annular flange portion 34 which provides abutments 35 against which the ends of the springs act. In order to minimize endwise movement oi the collar 33, the two springs 29 and 39 are preferably almost, but not 50 quite, fully compressed when the supporting means is assembled, as shown in Fig. 3.

Disposed within the bore of the collar 33 is a two-part sleeve 3S embracing a cylindrical attachment-supporting arm or tube 3l. Passing 55 through the supporting-arm 31 is an electric conductor cord 31. In order to loosen or tighten the two-part sleeve 36 upon the attachment-supporting arm 31, which is rotatably and endwise slidably adjustable in the mounting, there is preferably provided a thumb-screw 38, the shank of which projects through a comparatively large clearance aperture 39 in the casing 25, 26. This clearance aperture permits relative lateral move' ment between the thumb-screw and the casing. The thumb-screw is threaded into the central portion of the collar 33 and the inner end thereofl impinges against the upper part of the sleeve 36, clamping it upon the attachment-supporting arm 31 in any desired position of adjustment. As can be seen in Figs. 2 and 4, the two-part sleeve 36, is prevented from shifting endwise relative to the collar 33 by the set-screw 40, the inner end of which projects into semi-circular notches 4| formed in the closely spaced edges 42 of the twopart sleeve 36. Obviously, it is essential for adjustment purposes that the thumb-screw 38 be positioned so that it is readily accessible to the operator.

As disclosed in Figs. l and 3, the cylindrical attachment-supporting arm 31 projects beyond the ends of the casing 25, 26 through generous clearance apertures 43 formed in the casing. It will be observed that the supporting-arm 31 is sustained substantially horizontally in cantilever fashion, as distinguished from a pendent supporting arm.

Secured to the arm 31, preferably at its free end, is a two-part clamp 44 the spherically cupped j jaws of which grip one ball-shaped end of a link 45. The other ball-shaped end of this link is gripped by the spherically cupped jaws of the two-part clamp 46, the similar sections of which are each formed with suitably shaped jaws 41 bent to grip the cylindrical lamp-socket 48. As described in detail in my previous patent hereinbefore noted, the provision of the link 45 provides for the universal adjustment and positioning of the lamp relative to the sewing eld. Further, the friction swivel joints about the right-angularly related stud-screws I2 and 22 constitute co1- lectively a universal joint connection between the cylindrical attachment-supporting arm 31 and the sewing machine frame and enable the arm 31 to be shifted into any desired angular relationship with the bracket-arm 3.

It will be noted that the two helically coiled springs 29 and 3B support in compression the entire lighting device. Obviously with this arrangement, severe vibrations set up in the sewing machine are largely and effectively damped out and are not transmitted to the lamp-socket. It is understood that other forms of resilient means, such `as rubber cones, etc., may be used as effectively as the herein disclosed coiled springs for supporting the lighting attachment.

While I have illustrated and described the preferred form of construction for carrying my in vention into effect, this is capable of variation and modification, without departing from the spirit of the invention. I therefore do not wish to be limited to the precise details of construction set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

Having thus set forth the nature of the invention, what I claim herein is:

l. A resilient support for a lighting device having, in combination, an outer member, a floating collar disposed within said outer member and adapted to adjustably support a lighting device, clamping means including a sleeve carried by said collar for securing the lighting device in adjusted position, and opposed bee-hive springs interposed between said outer member and collar for yieldingly supporting the collar within the outer member.

2. A resilient support for a lighting device comprising a two-part cylindrical casing having inturned end-flanges, a floating collar formed with an annular flange disposed within said casing and adapted to adjustably support a lighting device, a clamping sleeve and thumb-screw securing means therefor carried by said collar, and opposed beehive springs under compression abutting against the inturned end flanges of the casing and the annular ilange of the collar for yieldingly supporting the collar within the casing.

REINHOLD E. voM LEHN.

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