US2696826A - Crutch - Google Patents

Description

E. R. DAVIES Dec. 14, 1954 CBUTCH Filed June 20, 1952 J. wig

INVENTOR EFF/C R .DfiV/ES BY W M ATTORN EY United States Patent CRUTCH Eric R. Davies, New York, N. Y., assignor to Roland Gwynne Davies, Colvcrley, Leeds, England Application June 20, 1952, Serial No. 294,537

' 4 Claims. Cl. 135-52 This invention relates to crutches and, more particularly, to an improved crutch which is comfortable to use.

A crutch is generally comprised as an upright member or limb which supports a shoulder rest at its upper end. Attempts to eliminate discomfort in the use of the crutches of the prior art have embodied, for instance, rubber pads on the shoulder rest to eliminate chafing. However, such a construction fails to eliminate pressure about the arm-pits, and such pads subjected to constant use restrict the flow of blood in the arms. Much of this pressure around the arm-pits exists because the shoulders of the user must rise in an arc as the body is swung forward on the crutch. It is preferable to make the crutch so that the shoulders of the user may move along a straight line which is substantially horizontal. However. in providing a means which allows the users shoulder to move straight forward and downwards, care must be taken not to exert other pressure on the armpit of the user which will cause discomfort.

Accordingly, the princi al object of the present invention is to provide a crutch which does not apply undue pressure to the users arm-nits and which is comfortable to use for a long period of time.

A further obiect of my invention is to provide a crutch which will allow the users shoulder to move forward and downward, the normal movement of the shoulder in walking, and not bear against the users arm-pit with undue pressure.

M re spec ficall an obiect of mv invention is to provide a pivoted shoulder rest, movable in a vertical direction, which will follow the users shoulder without undue ressure thereon.

A still further obiect is to provide for resilient resistance to shoulder-rest depression commensurate to the applied weight or pressure exerted by the user.

The above ob ects. and other ob ects which will become apparent as the description proceeds. are accomplished by providing a crutch having a pivoted shoulder rest so as to he movable in a vertical direction and by spring loadin the sh der rest by op sed resilient means, prefe bly of differing tensions, which tend to rotate the shoulder rest about the Divot in opposite directions. According to the ar itr rilv selected embodiment of the invention for this disclosure, the construction is such that the shoulder-re eiving part of the shoulder rest is mainlv in fr nt of the limb or forwardly of the pivotal mounting of the shoulder rest.

The pposed res lient means may be springs which are attached at one end to the shoulder rest and at the other end to the crutch limb, and with the springs at the front and back of the crutch and attached to the shoulder rest at opp site sides of the pivot; or the opposed springs may be enclosed within the limb member itself and the resultant force of the action of the springs applied to the shoulder rest.

Referring to the accom anying drawing in which like numerals of reference indicate similar parts throughout the several views:

Fi ure 1 is a side elevation showing my improved cru ch with the shoulder rest in normal position;

Figure 2 is an elevation looking at the ri ht side of Fi l. or at the rear of the crutch as preferably used;

Figure 3 is a view enlar ed from Fig. 1, showing the up er end of the crutch; and

Fi nre 4 is se nal elevation of the upper end of a modified construction.

In the particular embodiment of the invention shown in Figures 1 to 3 of the drawing, a limb or upright portion of the crutch, which may be made of tubular material of a required length to suit the particular user, is designated generally by the reference numeral 10. The basal end of the limb 10 is provided with a rubber tip or pad 11 to prevent the crutch from slipping when in use. At about midway of the length of the limb 10, a hand grip 12 is aifixed thereto, projecting laterally therefrom and arranged so as to slope slightly back from right angles to the body of the user. Holes 13 at intervals in the limb enable the hand grip to be adjusted for height. Also, the limb may be made of telescopic tubular sections secured by a removable stud 14 which passes through the telescoped sections in one of a series of holes 15 in the limb to allow adjustment of the length of the limb to suit the height of the particular user.

A movable shoulder rest 16 is pivotally mounted at the top of limb 10. For that purpose a stud 17 is shown with a neck 18 depending into the upper end of the tubular stock comprising the limb. Said stud 17 is provided with a flange 19 to rest on the upper end of the limb and has an upwardly projecting stem 20 to constitute the fixed hinge member for a pivotal mounting. The shoulder rest 16 has depending from its under side a downwardly directed hinge member 21 lapping the fixed member 20 of stud 17 and hinged thereto by pivot pin 22.

The shoulder rest 16 is held in its normal position, preferably horizontal, by opposed resilient means. form of opposed resilient means is shown in Figures 1 to 3 and comprises longitudinally coiled springs 23 and 24. In the specific showing of the drawing, two springs 23 are secured at the rear of the crutch, as by a yoke 25 at the lower ends of the springs, said yoke being engaged at its middle under a bolt or stud 26 projecting at the rear of the crutch. Suitable eyelets 27 are provided at the under part of the shoulder rest 16, rearwardly of the pivot, to receive the upper ends of said rear springs 23. These two springs have a combined tension sufficient to substantially support the weight of the user as he leans and swings forward in walking. It will be noted that when the user is erect, there is usually no weight on the shoulder rest, but the further forward the person leans, the more will be the weight applied to the shoulder rest. It is therefore desirable to have very light spring-loading at the normal or horizontal position of the shoulder rest and to have the spring-loading commensurately increase as the user applies more weight. Likewise, as the user returns to upright position it is desirable to lessen the spring loading and avoid jerking his shoulders suddenly upward. According to my invention, the upward pressure is eased off commensurate with the removal of the users weight against the shoulder rest, and thereby enables the shoulder rest to follow the users shoulder in an easy floating manner. For this purpose, I provide the front springs 24 to provide spring loading contra to that of the pair of rear springs. The front spring loading should be less than the rear spring loading, and as indicative of this circumstance, I show only a single spring 24 at the front of the crutch, it being shown as secured to the crutch by looplng at its lower end upon the front end of stud 26 and hooked at its upper end in an eyelet 27 depending from the shoulder rest 16 forwardly of the pivotal mounting.

The rear springs 23 tend to rotate the shoulder rest upon its pivot in a direction contra to that of the single front spring and exert greater tension than the front spring, and produce a combined action such that the greater the applied weight of the user, the greater will be the resistive tension of the rear springs assisted by the decreasing tension in the front springs. But as the users weight on the shoulder rest lessens, the front spring becomes effective to partly counteract the rear springs, preventing the shoulder rest from slapping against the arm-pit of the user, and permitting the users shoulder to move steadily horizontally forward.

According to the present showing, the shoulder rest has a greater length of projection forwardly than rearwardly from the pivot, and is of curved formation, here depicted as having an upwardly curved rearward Patented Dec. 14, 1954 One end 29 and an upwardly curved forward end 30 and with the up-curved forward end longer than the upcurved rear end. These curvatures form a good seating for the front and rear of the users shoulder next to the arm-pit. Furthermore, the shoulder rest is provided with suitable padding to form a good seating for the users shoulder. The rest is of narrow formation so as not to be objectionable under the arm-pit, and its greater length toward the front is to enable the users shoulder to be supported wholly or mainly forward of the limb.

The shoulder rest may have a permitted twist or rotation about the axis of the limb if so desired, and for this purpose a slot 32, extending in a circumferential direction, is provided near the top of the limb in the region occupied by neck 18 of stud 1 7, and a screw 33 passing through said slot and fixed in said neck keeps the stud assembled upon the limb but permits the desired rotation.

Furthermore, the amount of the upward or vertical swing of the shoulder test may be limited, and this limitation may be made adjustable by an adjusting screw 34 interposed between the stud and the flange 19. Also, adjustment of the spring tensions may be included, for instance by providing a choice of holes 35 in the limb 10 for the bolt or stud 26 to pass through.

In the modification of Figure 4, the pivoted mounting for shoulder rest 16 is offset from the axis of the limb 1t), and the opposed springs, preferably of different strength, are enclosed within the upper end of the tubular limb. For this purpose, a tubular collar is threaded or otherwise secured onto the upper end of limb 10. Extending horizontally or laterally from the collar in a rearward direction and then vertically or upward, is a tubular L-shaped fitting 41 which in effect forms an offset portion of limb 10. For the purpose of pivotally mounting the shoulder rest 16 on the limb 10, above described stud 17 is supported by the upper end of fitting 41 with the member 20 projecting upwardly to form a fixed hinge member cooperating with the movable hinge member 21 depending from the under part of the shoulder rest to form a hinge by inclusion of pivot pin 22 therethrough.

Enclosed within the upper portion of limb 10, and placed end to end are two longitudinally coiled springs 44 and 45, of which the lower one 44 preferably has greater strength or compressive tension than the upper one 45. The lower spring 44 may be supported at its bottom on a bolt 46 which passes transversely through the limb 10. The upper end of upper spring is arranged to bear against a ring 48 shown threaded into the upper end of collar 49, said ring providing an axial hole 50 therethrough.

To apply the resultant force of the springs 44 and 45 to the shoulder rest 16, a rod 51 is dependingly sup ported at its upper end from approximately the midpoint of the shoulder rest by an eyelet 52. The rod extends substantially along the axis of limb 10 and 1 r it) through said hole 50 of ring 48 and terminates in a loop juxtaposed to said eyelet to which it is pivoted. A plate 54 between the otherwise meeting ends of the springs 44 and 45, is adjustably supported, as by lock-nuts, on said rod. This plate 54 transmits the resultant force of the two springs to the shoulder rest through intervention of said rod 51.

The springs 44 and 45 are under compression and the degree of compression may be adjusted by varying the location of the supporting bolt 46 at the bottom of spring 44. The relative degree of compression between springs 44 and 45 may be regulated by varying the position of plate 54 on the rod 51. It will now be clear that the springs 44 and 45 will have the same effect on the movement of the shoulder rest as obtained by springs 23 and 24 of Figures 1 to 3.

I claim:

1. A crutch comprising a limb, a shoulder rest having a normal transverse relation to said limb and pivotally mounted thereon to swing vertically, and opposed resilient means resistive to swing of said shoulder rest on its pivotal mounting respectively to and from said normal relation, said means having greater resistive force to swinging of said shoulder rest in one direction than in the other direction.

2. A crutch comprising a limb, a shoulder rest transverse to said limb and having pivot connection thereto, said limb having greater length forwardly from said pivot connection than rearwardly therefrom, and opposed resilient means resistive to swing of said shoulder rest in either direction on said pivot connection, said means having greater resistive force to swinging the forward end of said shoulder rest downwardly than upwardly.

3..A crutch in accordance with claim 1 wherein said resilient means comprises a tensioned spring applying a downward force to said shoulder rest at a point forwardly of the pivotal support and a tensioned spring applying a downward force to said shoulder rest rearwardly of the pivotal support.

4. A crutch in accordance with claim 1 wherein said resilient means comprises opposed springs within said limb, and means to apply the resultant vertical force of said opposed springs to said shoulder rest at a part thereof away from the pivotal support of the said shoulder rest.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 467,675 McGrain Jan. 26, 1892 974,494 Jensen et al Nov. 1, 1910 1,183,008 Hipwood May 16, 1916 FOREIGN PATENTS Number Country Date 176,777 Canada May 1, 1917

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