A crutch

Description

[0001] This invention relates to crutches and it is an object of the invention to provide crutches which can be used by a patient to raise himself to a standing position.

[0002] Many patients who have leg disabilities have difficulty in raising themselves from a sitting position to a standing position unless they are able to use their arms to provide the necessary lift. Accordingly, such a patient normally has to receive some form of assistance to enable him to reach the standing position. Such patients frequently have to walk with the aid of crutches and, accordingly, it is a particular object of the present invention to provide crutches which enable a patient to raise himself from the sitting position.

[0003] United States Patent Specification No. 2 674 253 discloses a crutch including a portable frame having an arm rest, a hand-grip, a staff slidably carried by the frame, and a spring urging the staff away from the frame. A brake is provided to regulate sliding of the staff relative to the frame, and locking means are also provided for securing the staff in any one of a plurality of positions relative to the frame. When the crutch is to be used to enable a user to move from a standing position to a sitting position, the locking means are unlocked and the brake is used to control sliding movement of the staff relative to the frame against the action of the spring. When the crutch is to be used to help a user to return to a standing position from a sitting position, the locking means are again unlocked and the brake is used to control outward movement of the staff relative to the frame under the influence of the spring.

[0004] In contrast to the complicated structure of the crutch disclosed in the said United States Patent Specification the present invention aims to provide means by which a standard well-known type of elbow crutch could be provided with a very simple additional mechanism enabling it not only to fulfil the avowed purpose of the crutch disclosed in the said United States Patent Specification, but also to provide a crutch which can be used much more simply and satisfactorily by a disabled person than could a crutch constructed in accordance with the said United States Patent Specification.

[0005] The type of elbow crutch referred to comprises a main tubular member; an elbow support fitted on said main tubular member; a hand-grip fitted on said main tubular member; and a further tubular member slidable within said main tubular member. Such a crutch is not capable of being extended while it is in use. Crutches of this kind are designed to be adjustable in length so that they can be used by patients of different heights or having legs of different lengths. To enable the length of such a crutch to be adjusted, it normally has to be lifted from the ground and both hands are required to operate the locking mechanism and change the length of the crutch.

[0006] The invention consists in a crutch comprising: a main tubular member; an elbow support fitted on said main tubular member; a hand-grip fitted on said main tubular member; a further tubular member slidable within said main tubular member; a spring operative to urge said further tubular member out of said main tubular member; a first clamp secured to said further tubular member; a ring member slidable along said main tubular member; a toothed rack, one end of which is secured to said first clamp, and the other end of which is secured to said ring member; a second clamp secured to said main tubular member; a pawl pivotally mounted on said second clamp and provided with a projecting portion adapted to engage the teeth of said rack; an operating lever pivotally mounted on said main tubular member in the vicinity of said hand-grip; interconnecting means coupling said operating level to said pawl; and a further spring urging the projecting portion of the pawl to engage the teeth of the rack.

[0007] It is to be understood that the arrangement of the operating lever in the vicinity of the hand-grip enables a user of the crutch to engage and release the pawl by manipulating the lever with the hand which is gripping the hand-grip. When the user releases the operating lever, the further tubular member is securely locked within the main tubular member. However, when the user moves the lever towards the hand-grip by squeezing it with his fingers, the pawl is disengaged from the rack so that the further tubular member may be moved outwardly with respect to the main tubular member under the influence of the spring or may be moved into the main tubular member under the influence of the user's weight.

[0008] When a pair of crutches in accordance with the invention is used to enable a patient to raise himself from the sitting position to the standing position, he operates the lever on each crutch to reduce the length of the crutch to the minimum by pressing the crutch on the floor or other ground surface. He then places his arms through the elbow supports and, holding the hand-grips, places one crutch on each side of the chair in the vertical position. He then raises himself by supporting his weight with the two crutches alternately, operating the control lever of the crutch which is not supporting his weight, to allow that crutch to extend a short distance under the influence of the spring.

[0009] Preferably the interconnecting means between the operating lever and the pawl comprises a rod pivotally attached at one end to the pawl, and at the other end to the operating lever. However, in an alternative construction, the rod is replaced by a flexible cable or the like.

[0010] Preferably the teeth of the rack are shaped so that they positively prevent the end portion of the crutch moving outwardly from the main portion as well as moving inwardly into the main portion. However, if desired, the rack may be in the form of a ratchet so that the end portion can move with respect to the main portion without operation of the control lever. With this arrangement, the spring loading on the pawl must be so arranged in relation to the spring loading on the extensible end portion that there is no unintentional extension of the crutch.

[0011] It is to be understood that a known form of crutch may be readily converted into a crutch in accordance with the invention by the addition of the manually-operable lever and the locking means for preventing relative movement between the extensible end portion and the main portion. Similarly, if at any time it is desired to use the crutch in the normal manner, the manually-operable lever and the locking means can be removed therefrom.

[0012] One method of performing the invention will now be described with references to the accompanying diagrammatic drawings, in which:-

Figure 1 is a side view of a clutch in accordance with the invention; and

Figure 2 is an enlarged view, partly in section, of the crutch illustrated in Figure 1.

[0013] The crutch illustrated includes a main tubular member 1, to which is fitted an elbow support 3 and a boss 9 carrying a hand grip 2. A further tubular member 4 is slidable within the tubular member 1, and is provided with a rubber ferrule on the outer end thereof. Both tubular members consist of aluminium or an aluminium alloy, and the tubular member 4 is urged out of the tubular member 1 by means of a steel spring 6, one end of which bears on a plug 7 inserted in the end of the tubular member 4. The other end of the spring 6 bears on a further plug (not shown) in the tubular member 1. This further plug is held in position within the tubular member 1 by means of a pin 8 passing through the boss 9.

[0014] A clamp 10 is secured to the tubular member 4 and supports one end of a steel rack 11 enclosed between two steel strips 12. The other ends of the rack 11 and the strips 12 are secured to a ring member 13 which is slidable along the tubular member 1.

[0015] A further clamp 14 is secured to the tubular member 1, and a steel pawl 15 is pivotally mounted on the clamp 14 by means of a pivot pin 16. The pawl 15 is provided with a projecting portion 17 adapted to engage the teeth 18 of the rack 11. A stainless steel rod 19 is pivotally attached at one end to the pawl 15 and, at the other end, to an aluminium operating lever 20. The lever 20 is pivotally mounted on the tubular member 1 by means of a clamp member 21. It will be understood that the position of the pawl 15 about its pivot axis is determined by the position of the lever 20, and the rod 19 is urged by a spring 22 in the direction necessary to cause the projecting portion 17 of the pawl 15 to engage the teeth of the rack 11.

[0016] Normally the spring 22 will cause engagement between the pawl 1 and the rack 11 so that the tubular member 4 is substantially locked in position in the tubular member 1. However, if the operating lever 20 is moved towards the hand grip 2, the pawl will be moved into the position shown in broken lines in Figure 2, so that it will be disengaged from the rack and, if no pressure is applied to the crutch, the tubular member 4 will move out of the tubular member 1 under the influence of the spring 6. On the other hand, if pressure is applied to the crutch with the ferrule 5 in engagement with the ground, the tubular member 4 will be moved into the tubular member 1. When the lever 20 is released, the pawl will be returned to the position shown in full-lines in Figure 2 to limit any further relative movement of the two tubular members.

[0017] If desired, the simple rack and pawl mechanism illustrated may be replaced by any of the well-known mechanisms for ensuring that the pawl moves only one tooth along the rack each time the lever 20 is operated.

Claims

1. A crutch comprising: a main tubular member (1); an elbow support (3) fitted on said main tubular member; a hand-grip (2) fitted on said main tubular member; a further tubular member (4) slidable within said main tubular member; a spring (6) operative to urge said further tubular member out of said main tubular member; a first clamp (10) secured to said further tubular member; a ring member (13) slidable along said main tubular member; a toothed rack (11), one end of which is secured to said first clamp (10), and the other end of which is secured to said ring member (13); a second clamp (14) secured to said main tubular member; a pawl (15) pivotally mounted on said second clamp and provided with a projecting portion (17) adapted to engage the teeth of said rack; an operating lever (20) pivotally mounted on said main tubular member in the vicinity of said hand-grip; interconnecting means (19) coupling said operating lever to said pawl; and a further spring (22) urging the projecting portion of the pawl to engage the teeth of the rack.

2. A crutch as claimed in Claim 1, wherein the hand-grip (2) is carried by a boss (9) secured to the main tubular member.

3. A crutch as claimed in Claim 1 or Claim 2, wherein the toothed rack (11) is enclosed between two strips (12) which prevent lateral movement of said pawl when it is in engagement with the rack, each of said strips being secured at one end to said first clamp, and at the other end to said ring member.

4. A crutch as claimed in any of the preceding Claims, wherein said interconnecting means (19) comprise a rod pivotally attached at one end to said pawl, and at the other end to said operating lever.

5. A crutch as claimed in Claim 4, wherein one end of said further spring is attached to said rod, while the other end of said further spring is attached to said second clamp.

6. A crutch as claimed in any of the preceding Claims, wherein the operating lever (20) is pivotally mounted on a third clamp (21) secured to the main tubular member.

Ansprüche

1. Krücke mit einem rohrförmigen Körper (1); einer an dem genannten rohrförmigen Hauptkörper befestigten Ellbogenstütze (3); einem an dem genannten rohrförmigen Hauptkörper angebrachten Handgriff (2); einem weiteren innerhalb des genannten rohrförmigen Hauptkörpers verschiebbaren rohrförmigen Körper (4); einer Feder (6), die den genannten weiteren rohrförmigen Körper aus dem genannten rohrförmigen Hauptkörper herausdrängt; einer ersten Klemme (10), die an dem genannten weiteren rohrförmigen Körper befestigt ist; einem entlang dem genannten rohrförmigen Hauptkörper verschiebbaren Ringglied (13); einer gezahnten Stange (11), deren ein Ende an der genannten ersten Klemme (10) und deren anderes Ende an dem genannten Ringglied (13) befestigt ist; einer an dem genannten rohrförmigen Hauptkörper befestigten zweiten Klemme (14); einer an der genannten zweiten Klemme drehbar gelagerten mit einem vorspringenden Stück (17) zum Einrasten der Zähne der genannten Stange versehenen Klinke (15); einem in der Nähe des genannten Handgriffs an dem genannten rohrförmigen Hauptkörper drehbar befestigten Betätigungshebel (20); Verbindungsmittel (19), die den genannten Betätigungshebel an die genannte Klinke koppeln; und einer weiteren Feder (22), die das vorspringende Stück der Klinke dazu drängt, die Zähne der Stange einzurasten.

2. Krücke nach Anspruch 1, bei der der Handgriff (2) von einer an dem rohrförmigen Hauptkörper befestigten Nabe (9) getragen wird.

3. Krücke nach Anspruch 1 oder 2, bei der die gezahnte Stange (11) zwischen zwei Leisten (12) eingeschlossen ist, die ein seitliches Bewegen der Klinke verhindern, wenn sie mit der Stange in Eingriff steht, wobei jede der genannten Leisten an einem Ende der genannten ersten Klemme und an dem anderen Ende an dem genannten Ringglied befestigt ist.

4. Krücke nach einem der vorhergehenden Ansprüche, bei der die genannten Verbindungsmittel (19) eine Strebe besitzen, die an einem Ende an der genannten Klinke und an dem anderen Ende an dem genannten Betätigungshebel drehbar angebracht ist.

5. Krücke nach Anspruch 4, bei der ein Ende der genannten weiteren Feder an der genannten Strebe angebracht ist, während das andere Ende der genannten Feder an der genannten zweiten Klemme befestigt ist.

6. Krücke nach einem der vorhergehenden Ansprüche, bei der der Betätigungshebel (20) drehbar an einer an dem rohrförmigen Hauptkörper befestigten dritten Klemme gelagert ist.

Revendications

1. Béquille comprenant un corps principal tubulaire (1), un support de coude (3) emmanché sur ce corps tubulaire, une poignée (2) fixé sur le corps tubulaire, un autre organe tubulaire (4) coulissant à l'intérieur du corps tubulaire principal, un ressort (6) agissant pour pousser cet autre organe tubulaire hors du corps tubulaire principal, un premier crampon (10) pour fixer cet autre organe tubulaire (4), un anneau (13) coulissant le long du corps tubulaire principal (1), une crémaillère (11) dont une extrémité est fixée au premier crampon (10) et l'autre extrémité est fixée à l'anneau (13), un second crampon (14) fixé au corps tubulaire principal (1), un cliquet (15) monté pivotant sur ce second crampon (14) et pourvu d'un appendice (17) adapté pour s'engager dans la denture de la crémaillère (11), un levier de manoeuvre (20) monté pivotant sur le corps tubulaire principal (1) au voisinage de la poignée (2), des moyens d'interconnexion (19) accouplant le levier au cliquet, et un autre ressort (22) poussant l'appendice du cliquet vers son engagement dans la denture de la crémaillère.

2. Béquille suivant la revendication 1, caractérisée en ce que la poignée (2) est supportée par un bossage (9) fixé au corps tubulaire principal (1).

3. Béquille suivant l'une des revendications 1 ou 2, caractérisée en ce que la crémaillère (11) est comprise entre deux bandes (12) qui s'opposent à un déplacement latéral du cliquet lorsqu'il est engagé dans la crémaillère, chacune de ces bandes étant fixée, par une extrémité, au premier crampon (10), et, par son autre extrémité, à l'anneau coulissant (13).

4. Béquille suivant l'une quelconque des revendications 1 à 3, caractérisée en ce que les moyens d'interconnexion (19) comprennent une tige fixée, à pivotement par une des ses extrémités, au cliquet, et par son autre extrémité au levier de manoeuvre (20).

5. Béquille suivant la revendication 4, caractérisée en ce qu'une extrémité de l'autre ressort (22) est fixée à la tige tandis que son autre extrémité est fixé au second crampon.

6. Béquille suivant l'une quelconque des revendications 1 à 5, caractérisée en ce que le levier de manoeuvre (20) est monté sur un troisième crampon (21) fixé lui-même au corps tubulaire principal (1).

Drawing