WO1992006661A1

WO1992006661A1 - Handbrake for wheeled vehicles

Info

Publication number: WO1992006661A1
Application number: PCT/SE1991/000611
Authority: WO
Inventors: Per Elvinsson
Original assignee: Etac Ab
Priority date: 1990-10-23
Filing date: 1991-09-16
Publication date: 1992-04-30
Also published as: DE4193708T1; SE9003375D0; CA2094502A1; SE468621B; SE9003375L; DE9190147U1

Abstract

A brake device for a walker, rollator or the like has a wheel with a brake which, via a strand (19), is connected to an operating portion (10) a distance beneath the handle (9) of the rollator. The operating portion (10) is secured with its one end (13) in the handle (9) and, with its other end (11), in a rocker (12) pivotal about a pivot shaft (16) and secured beneath the handle (9). The strand (19) is secured in the rocker (12) such that the brake is activated when the rocker (12) is pivoted in that the operating portion (10) is pulled upwardly towards or pushed down from the handle (9). The rocker (12) is pivotal between abutments (17, 18) and may, by depression of the operating portion (10), be pivoted to the abutment (18) such that the strand (19) here passes the pivot shaft (16) and the rocker (12) passes its dead centre and in such instance holds the brake in the braking position.

Description

HANDBRAKE FOR WHEELED VEHICLES

TECHNICAL FIELD

5 The present invention relates to a brake device for a wheeled implement or vehicle including at least one wheel fitted with a brake, a connection device such as a line or rod provided for operating the brake, a gripping portion on the implement for maneuvering thereof, and a handle device disposed a slight distance from the gripping portion and substantially therealong, the handle 1 0 device being, with a first end, secured in the implement.

BACKGROUND ART

Wheeled implements or vehicles of the type mentioned by way of introduction 15 are employed as walking aids for people suffering from greater or lesser disability, for example the elderly or people undergoing rehabilitation after an accident. These implements are also variously entitled walkers, wheeled walking frames, or rollators and, to be able to fulfil their function, must be highly maneuverable and, in particular must not require any appreciable 20 degree of strength on the part of the user operating the brakes, irrespective of whether this applies to normal braking or parking braking.

An implement (rollator ) of the type mentioned by way of introduction is previously known from SE-C-442 731. In this prior art implement, the brake

25 device has a portion of a cable secured along and in slight spaced apart relationship from a handle fitted on the implement. This portion is pivotally secured with one end section in an anchorage on the handle. Furthermore, the cable is, at the opposite end of this portion, longitudinally displaceably passed through a guide, whereby drawing of the portion towards the handle

30 will realise application of the brake. For parking braking, the portion is provided with a fixed stop at the guide and a U-shaped channel projecting towards the anchorage is disposed beneath the guide, and the stop may be caught against the free end of the channel when the portion is pressed downwards from the handle.

Jb

The employment of a cable (often called a wire) in the prior art design and construction requires considerable space, since the cable cannot be bent sharply without a deterioration of or obstruction to its function. Furthermore, the cable employed constitutes an irritating fault source since it often breaks. Finally, for maneuvering the brake to the parking position, such large forces are required that a handicapped person, for example someone suffering from rheumatism, would not be capable of carrying out this manoeuvre. 5

PROBLEM STRUCTURE

The present invention has for its object to realise a brake device of the type mentioned by way of introduction, the brake device being designed in such a

1 0 manner as to permit full operation already upon the application of very slight forces. The present invention further has for its object to realise a brake device which requires no major maintenance adjustment, the previously employed cable having been eliminated and the force transmission between the operating device of the brake and the brake proper being effected in a manner

15 which does not require considerable space, finally, the present invention further has for its object to realise a brake device which is simple and economical in manufacture and is extremely operationally reliable.

SOLUTION 0

The objects forming the basis of the present invention will be attained if the brake device intimated by way of introduction is characterized by a portion connected to the implement and pivotal about a pivot shaft, in which portion the connection device is secured in spaced apart relationship from the pivot 5 shaft such that the brake is actuable by rotation of the pivotal portion in a first direction, the other end of the handle device being secured in the pivotal portion a distance from the pivot shaft such that, in the non-activated position of the brake, an actuation of the handle device towards or away from the gripping portion will rotate the pivotal portion in the first direction.

30

In one preferred embodiment, it further applies according to the present invention that the pivotal portion is pivotal within such a pivotal radius defined by abutments that, at the ends of the pivotal radius, the connection device is located on opposite sides of the pivot shaft. ό >

Since the connection device, on activation of the brake, thus passes over dead centre, i.e. past the pivot shaft, a considerable braking force will be generated on slight operating power and, furthermore, the possibility of function as parking brake will also be afforded.

Further advantages will be achieved if the brake device is also given one or more of the characterizing features as set forth in appended Claims 3 and 4.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will now be described in greater detail hereinbelow, with particular reference to the accompanying Drawings, in which:

Fig. 1 shows, straight from the side, an upper portion of an implement (rollator fitted with the brake device according to the present invention, the brake device being located in the non-activated state;

Fig. 2 shows a lower portion of the implement of Fig. 1 ; and

Fig. 3 is a view corresponding to that of Fig. 1, but with the brake device in the activated, parking position.

DESCRIPTION OF PREFERRED EMBODIMENT

It will be apparent from Fig. 1 that the implement has a rear frame section 1 with downwardly directed shanks which carry wheels (not shown in this Figure). The upper end of the rear frame is bent forwardly and there assumes an approximately horizontal recumbent, roughly U-shaped form. It is apparent from the Drawing that the implement also has a front frame 2 with downwardly directed shanks whose lower ends are fitted with pivotal wheels. The front frame 2 is connected to the rear frame 1 by the intermediary of joints 3 so that the frames 1 and 2 are pivotal in relation to one another between the opened position of use illustrated in Fig. 1 and a collapsed position in which the front frame 2 is swung in towards the rear frame.

Fig. 2 shows the lower end of the rear frame 1, it being apparent from this Drawing that each downwardly directed shank in the rear frame is fitted with a wheel 4. Furthermore, there is provided, in the region above the wheel, a pivotal arm 6 with a laterally directed projection 7. The pivotal arm 6 is secured by the intermediary of a joint 8 and is pivotal in accordance with the arrow A so that the projection 7, on pivoting in a clockwise direction by upward pulling of a connection device 19, may be brought into engagement with the periphery of the wheel 4 so that the wheel is thereby braked.

In order to ensure that the pivotal arm 6 and, in particular, its lateral projection 7 do not continuously drag against the periphery of the wheel 4, a return spring is provided which strives to pivot the arm 6 in a counterclockwise direction, possibly into abutment against a stop.

The transitional region, shown in Fig. 1 , between the downwardly directed shanks of the rear frame 1 and the horizontal formation constitute gripping portions 9 or handles which the user grasps when the implement is being propelled. A slight distance beneath these gripping portions 9, and substantially therealong, there is provided a handle device 10 which, with its one end 11, is secured in a pivotal portion 12 or rocker. The other end 13 of the handle device 10 is secured in an anchorage 14 designed as a projecting stub shaft on the second frame 2.

The handle device 10 may be produced from a flexible, strip shaped and substantially inextensible material, such as for example a planar woven strap, a strand or the like. In the released, non-braking state illustrated in Fig. 1, the handle device 10 extends approximately rectilinearly between the stub shaft 14 and its anchorage 11 in the rocker 12. In this position, the handle device is more or less stretched and is located at such a distance from the gripping portion 9 that it is readily accessible by a hand, with the wrist resting on the upper side of the gripping portion.

The rocker 12 is pivotally secured on a stirrup bar 15 so that the rocker is pivotal, about a pivot shaft 16, between the positions illustrated in Figs. 1 and 3. The rocker 12 has a pivotal radius which is defined by abutments 17 and 18 on the outside of the stirrup bar.

The rocker itself is designed as a U-shaped yoke seen in the longitudinal direction of the handle device 10 and has its shanks on the outside of the stirrup bar 15, which has two approximately mutually parallel shanks. The distance between these shanks is so large that a connection device 19 may move in between them, this device being, with its one end, secured in the rocker and, with its other end (see Fig. 2), secured in the pivotal brake arm 6. An upward pulling of the connection device 19 realises, as is apparent from Fig. 2, a braking of the wheel 4.

The pivotal radius which is permitted for the rocker 12 by the two abutments 17 5 and 18 is of such magnitude that, when the rocker is pivoted from the position according to Fig. 1 (brake released) to the position according to Fig. 3 (parking brake), the connection device 19 will pass from one side of the pivot shaft 16 to the other side thereof. Thus, the connection device 19 passes over dead centre.

1 0

The connection device 19 may, in practice, consist of a substantially inextensible strand, a woven, planar strap, but may also be a rod. The length of the connection device 19 is adapted in such a manner that, with the rocker 12 in the position as shown in Fig.1, the pivotal brake arm 6 is located in the

1 5 non-activated state according to Fig. 2. On commencement of pivoting of the rocker 12 in a counterclockwise direction, the connection device 19 will, however, be drawn upwardly, as a result of which the brake arm 6 is pivoted in a clockwise direction into engagement with the periphery of the wheel 4. With the correct adjustment of the brake, this will occur somewhere between the

20 position of the rocker according to Fig. 1 and a position in which the connection device 19 is located in register with the pivot shaft 16. Suitably, application of the brake may also take effect approximately centrally of this region.

25 On pivoting of the rocker 12 so far in a counterclockwise direction that the connection device 19 passes the pivot shaft 16, a somewhat downwardly directed movement will once again be imparted to the connection device (which thus acts on the brake in its direction of release). However, the abutment 18 is located in such a position that the continued pivoting of the

30 rocker 12 is arrested already when the connection device 19 is located but a slight distance past the pivot shaft 16 in a direction to the left in Fig. 1. This position is clearly illustrated in Fig. 3. In this position, the brake arm 6 is located with the projection 7 in hard contact with the periphery of the wheel 4 so that the vehicle is braked for parking. j

The length of the handle device 10 is adapted in such a way that, when the handle device is pulled upwardly towards the gripping portion 9, pivoting of the rocker 12 will be effected in a counterclockwise direction so far that braking is realised. Since the direction of pull from the handle device 10 is directed obliquely upwardly, the rocker 12 will not be capable of being pivoted so far that the connection device 19 passes the pivot shaft 16. Alternatively (depending somewhat on the placing of the hand), the handle device 10 will come into abutment against the underside of the gripping portion 9 before the connection device 19 has passed over dead centre. This implies that it is impossible to realise parking braking by actuating the handle device in an upward direction.

If the handle device 10 is instead subjected to a downwardly directed, force, there is no limit to how far the rocker 12 may be pivoted in a counterclockwise direction other than that limit defined by the abutment 18. This entails that parking braking may simply be realised by pressing the handle device 10 in a downward direction.

It will be apparent from Fig. 3 that if the handle device 10 is pulled upwardly, this will entail an actuation of the rocker 12 in the clockwise direction so that thereby parking braking is cancelled and the brake, by the action of the above- mentioned return spring, snaps over to the position according to Fig. 1.

Because the anchorage 20 of the connection device 19 in the rocker 12, spaced apart from the pivot shaft 16, lies relatively high on the pivot arc which the anchorage point 20 passes through, a very large upwardly directed tractive force will be generated in the connection device 19 already when the rocker 12 is subjected to quite insignificant torque. Since, in addition, the direction of pull which the handle device 10 exercises on the rocker (at least during the major part of the braking cycle), is directed approximately at right angles to a line between the pivot shaft 16 and the anchorage 11 of the handle device 10 in the rocker, maximum torque will be achieved in relation to the force exercised on the handle device 10. In other words, the rocker acts as a force amplifier gear arrangement.

In Fig. 2, the solid line 19 represents the connection device in that position which this assumes when the brake is not activated, while the broken line 19' shows the direction of the connection device in that position this assumes in the parking braked state (according to Fig. 3). The present invention may be modified without departing from the spirit and scope of the appended Claims.

Claims

1. A brake device for a wheeled implement or vehicle including at least one wheel (4) fitted with a brake (6, 7), a connection device (19) such as a strand or a rod provided for operating the brake, a gripping portion (9) on the implement for maneuvering thereof, and a handle device (10) disposed in slight spaced apart relationship from the gripping portion and substantially therealong, the handle device being secured in the implement by means of a first end (13), characterized by a portion (12) connected to the implement and pivotal about a pivot shaft (16), in which portion the connection device (19) is secured in spaced apart relationship from the pivot shaft such that the brake (6, 7) is actuable by pivoting of the pivotal portion in a first direction, the other end (11) of the handle device (10) being secured in the pivotal portion in spaced apart relationship from the pivot shaft such that, in the non-activated position of the brake, an actuation of the handle device towards or away from the gripping portion (9) pivots the pivotal portion in the first direction.

2. The brake device as claimed in Claim 1 , characterized in that the pivotal portion (12) is pivotal within such a pivot radius defined by abutments (17, 18) that, at the ends of the pivot radius, the connection device (19) is located on opposite sides of the pivot shaft (16).

3. The brake device as claimed in Claim 2, characterized in that the connection device (19) is of such length that the brake (6, 7) is fully activated when, during the pivoting of the pivotal portion (12) in the braking direction, the connection device (19) passes the pivot shaft (16); and that one abutment (18) is disposed to arrest the pivotal portion somewhat after the connection device has passed the pivot shaft.

4. The brake device as claimed in Claim 2 or 3, characterized in that the handle device (10) is of such length that it extends substantially rectilinearly to the pivotal portion (12) in the non-activated position of the brake; and that on pulling towards the gripping portion (9), it realises a pivoting of the pivotal portion such that the connection device (19) moves towards but not past the pivot shaft (16).