GB2437300A

GB2437300A - Braking system for linked hand propelled vehicles

Info

Publication number: GB2437300A
Application number: GB0607665A
Authority: GB
Inventors: Donna Naseby
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-04-19
Filing date: 2006-04-19
Publication date: 2007-10-24
Also published as: GB0607665D0

Abstract

First and second vehicle units such as strollers (1) are connected together. A brake element (11) is associated with a wheel (6) of the first vehicle unit which is removed to connect the said first vehicle unit to the second vehicle unit. The brake element (11) is aligned with a wheel of the said second vehicle unit so that when the brake of first vehicle unit is engaged the said brake element (11) engages with the wheel (7) of the said second vehicle. Applying the brake of the first vehicle also engages the brake associated with the wheel of the said first vehicle which is not removed (7) in joining the first and second vehicles and therefore applying the brake of the first vehicle engages brakes on two spaced apart wheels. When the brake of the second vehicle (none of the wheels of the second vehicle are removed to join the said first and second vehicles) is applied, brake elements (15, 11) engage with wheels on both sides of the vehicle.

Description

Braking System for a Hand Propelled Vehicle

Field of the Invention

The present invention relates to a braking system for a hand propelled vehicle, and in particular to a braking system for a hand propelled vehicle formed from a plurality of vehicle units.

Background of the Invention

In UK patent application number 053527.4 there is described hand propelled load carrying vehicle comprising at least first and second vehicle units attachable one to another. To attach the vehicle units together the wheels and handle on one side of one unit are removed, and that side is connected to the side of another unit. The handle is used to secure the units together.

One potential problem which has been identified with this type of vehicle is that the braking systems of the units which arc joined together must be operated independently of each other.

Furthermore, one of the wheels of braked wheels of one of the vehicle units is removed to attach the vehicle united together Therefore one part of the vehicle has a reduced braking capacity.

In order to be able to market hand propelled vehicle as a child's pushchair or pram a safety standard must be passed. The safety standard includes a standard for braking effectiveness. The current test British Standard test for vehicles for carrying children is that the brakes must hold the pram stationary when on an incline of 9 degrees.

The present invention seeks to provide an efficient braking system for a hand propelled vehicle of the type described briefly above, and in greater detail in GB 0503527.4.

Summary of the Invention

According to one aspect of the invention there is provided a braking apparatus as specified in Claim 1.

Preferred features of the invention are described in the claims dependent on Claim 1, the

following description and the drawings.

The braking system of the present invention provides a simple and effective arrangement which ensures that which ever brake is applied at least two sets of wheels will be braked.

Each embodiment of the invention is concerned with a vehicle having a braking system of the type which engages with the surface of the wheel which engages with the surface supporting the vehicle, as opposed to braking systems which engage with the faces of the wheels perpendicular to the surface supporting the vehicle.

In one embodiment of the invention, when first and second vehicle units are connected together the brake element associated with a wheel of the first vehicle unit which is removed to connect the said first vehicle unit to the second vehicle unit is aligned with a wheel of the said second vehicle unit so that when the brake of first vehicle unit is engaged the said brake element engages with the wheel of the said second vehicle. Applying the brake of the first vehicle also engages the brake associated with the wheel of the said first vehicle which is not removed to join the first and second vehicles and therefore applying the brake of the first vehicle engages brakes on two spaced apart wheels. When the brake of the second vehicle (none of the wheels of the second vehicle are removed to Join the said first and second vehicles) is applied, brake elements engage with wheels on both sides of the vehicle.

In the second embodiment of the invention, when first and second vehicle units are connected together the brake element associated with a wheel of the first vehicle unit which is removed to connect the said first vehicle unit to the second vehicle unit connects with the brake of the said second vehicle unit so that when the brake of first vehicle unit is engaged the brake of the second vehicle is also engaged.

In a third embodiment of the invention the brake element of the first vehicle is arranged to engage with a wheel of the second vehicle and to interconnect with a brake element of the second vehicle.

Brief Description of the Drawings

In the drawings, which illustrate preferred embodiments of the invention, and are by way of

example:

Figure 1 is a rear view of a pair of vehicles units of a hand propelled vehicle according to the invention prior to attachment of one vehicle unit to the other; Figure 2 is a rear view of the pair of vehicle units illustrated in Figure 1 attached to each other; Figure 3 is a side view of part of the braking system of the invention; Figure 4 is a rear view of the part of the braking system illustrated in Figure 3; Figure 5 is a rear view of a pair of vehicles units of a hand propelled vehicle according to another embodiment of the invention prior to attachment of one vehicle unit to the other; Figure 6 15 a rear view of the pair of vehicle units illustrated in Figure 5 attached to each other; and Figure 7 is a side view of part of an alternative brake engagement mechanism of the invention.

Detailed Description of the Preferred Embodiments

Figure 1 illustrates the rear of two identical vehicle units which when attached form a hand-propelled vehicle. Each vehicle unit 1 comprises two sets of wheels 2, 3, one set 2 being mounted on a shaft 5 which may be attached and detached from an upright member 4 located to the other side of the vehicle unit I and the other set 3 being fixed to an upright member 8 located to one side of the vehicle unit 1.

Each set of wheels 2, 3 is provided with a brake assembly. The brake assembly 10 associated with the set of wheels 2 comprises a brake element 11 which is selectively engagable with both wheels 6 of the set 2. The brake element 11 is mounted on a lever 12, which lever is attached to the upright member 4 by a pivot mounting 13 (described in greater detail with reference to Figures 3 and 4). A spring extends between the lever 12 and the upright 4 to bias the brake element 11 into engagement with the surface of both wheels 6 of the set 2. The braking assembly 14 associated with the set of wheels 3 comprises a brake element 15 which is selectively engagable with both wheels 7 of the set 3. The brake element 15 is mounted on a lever 16, which lever is attached to the upright member 8 by a pivot mounting 17. A spring extends between the lever 16 and the upright 8 to bias the brake element 15 into engagement with the surface of the inner most wheel 7 of the set 3. A cross-member links the brake assemblies 2, 3 together so that when one of the brake assemblies is engaged or disengaged the other is similarly engaged or disengaged.

Referring now to Figure 2, the pair of vehicle units I are attached together by detaching the wheel set 2 from the upnght 4 and inserting the lower part of the upright 4 into the bracket 9. With the two vehicle units I attached together as illustrated in Figure 2, the brake element 11 aligns axially with the brake element 15, and is aligned radially with the outer most wheel 7 of set 3. In the example illustrated in Figures 1 to 4, the brake elements 11 and 15 are each provided with respective parts of a coupling so that with the two vehicle units attached to each other as illustrated in Figure 2 the brake clement 11 is attached to the brake element 15 (the coupling is described in greater detail with reference to Figures 3 and 4. In use, with the brake elements 11 and 15 are coupled, when any one brake assembly is engaged or disengaged, all the brake assemblies of the connected vehicle units are engaged or disengaged.

In another embodiment illustrated in Figures 5 and 6, the brake elements 11 and 15 are not coupled. Nevertheless, engaging the brake of one of the vehicle unit always results in a wheel of two spaced apart sets of wheels being engaged as the brake element 11 of the brake assembly 10 associated with the wheel set 2 which has been removed to join the vehicle units 1 together engages with the surface of a wheel 7 of the wheel assembly 3 of the other vehicle unit. \Xlhilst interconnection of the brake assemblies of the vehicle units I is preferred it is possible that for certain configurations of hand-propelled vehicle an adequate degree of braking can be achieved by braking some of the wheels of the said vehicle.

Figure 3 is a side view of a removable wheel set 2. The brake element his mounted on a lever 12 which is mounted on the upright 4 by a pivot 13 so that the brake element can be moved into and out of engagement with the surface of the wheel 6. Mounted on the upright 4 is a bracket 20 which is formed from a flexible material and provides for engagement and disengagement of the brake element 11 with the wheel 6. The bracket 20 includes two recesses 21, 21'. An end 23 of the lever 13 engages with one of the recesses 21, 21'. With the end 23 located in the recess 21' the brake element 11 is disengaged from the surface of the wheel 6. With the end 23 located in the recess 21 the brake element 11 engages with the surface of the wheel 6 to brake the vehicle. The spnng 19 serves to bias the brake element 11 into engagement with the wheel 6. The spring 19 ensures that in the event of the lever 12 not being moved sufficiently far for the end 23 of the lever 12 to engage with the recess 21' the lever 12 will be pulled into engagement with the recess 21 and the brake being applied. Similarly, if in attempting to engage the brake element hI the lever 12 is not moved sufficiently, the spring 19 assists in pulling the lever 12 so that the end 23 engages with recess 21.

The brake element 11 includes part of a coupling, which in the present example is a male/female coupling. The end 24 of the brake clement (shown in broken lines) forms the male part of a coupling, with the female part of the coupling forming part of the brake element 15. A securing clement in the form of a catch 26 may be provided to secure the brake elements 11 and 15 together.

However, a securing element 26 in fact should not be necessary as the male part of the coupling is inserted into and removed from the female part axially in the direction indicated by arrows X. When the brake is actuated the brake elements move rotationally about the pivot point 13 in the direction indicated by arrows Y. Hence engagement and disengagement of the brake does not impart a force on the brake elements 11, 15 having a direction which would cause the brake elements 11, 15 to become disengaged.

Figure 4 is a rear view of a part of a hand-propelled vehicle comprising two vehicle units attached to each other. An upright 4 of a first vehicle unit I is attached to an upright element 8 of another vehicle unit I by means of a bracket 9. As described above, the brake assemblies 10 and 14 of the vehicle units I comprise brake elements 11 and 15 respectively and compnse male and female elements 24 and 25 respectively of a coupling. An advantage of the arrangement illustrated in Figures 1 to 4 is that if both brake elements 11, 15 are not in the same brake engaged configuration the male coupling element will not insert into the female coupling element which itself prevents the upright 4 from locating fully in the bracket 9, which prevents the two vehicle units from being attached together, i.e. a mechanism is provided whereby the vehicle units may only be connected together when the brakes of the said vehicle units are applied.

In another embodiment shown in Figure 7 (where like reference numerals are used to indicate like parts), rather than the brake elements engaging with the surface of the wheels, the brake element comprises a fork 32 which engages with a recess 33 associated with a wheel. The brake element includes a male part 31 of a coupling which engages with a corresponding female part of the coupling.

Claims

Claims A hand propelled load carrying vehicle comprising at least first

and second vehicle units attachable one to the other; each vehicle unit comprising two spaced apart side frames and a load supporting means l)etween the two side frames, each side frame mounng at least a rear wheel and a handle member; wherein at least the rear wheel of at least one side frame of one of the vehicles is detachably mounted on the said frame; wherein at least one of the side frames of one of the vehicle units includes a first part of an attachment means and at least one of the side frames of the other vehicle comprises a second part of the attachment means; wherein the first part of the attachment means comprises at least two brackets secured to a said side frame at spaced apart locaons, and the second part of the attachment means comprises at least two attachment elements, each element co-operating with one of the said at least two brackets to attach the two vehicle units together; wherein the or each of the detachably mounted wheels arc each attachable to one of the said at least two attachment elements, and wherein detaching one of the said detachably mounted wheels reveals one of the said attachment elements; and a braking system associated with each rear wheel, the braking system comprising a selectively engagable brake element, wherein the braking element is moved in a substantially radial direction of the rear wheel to move between engaged and disengaged positions, and wherein engaging the brake of one vehicle unit brakes at least a wheel associated with two space apart side frames.

2. A hand propelled vehicle as claimed in Claim 1, wherein the brake element engages with a surface of a wheel of the vehicle.

3. A hand propelled vehicle as claimed in Claim 1 or 2, wherein each side frame is provided with a set of wheels and wherein the brake element associated with the side frame to which the rear wheel set is detachably mounted extends over at least two wheels of the set, and the brake element associated with the side frame to which the rear wheel set is fixedly mounted extends over one wheel of the set.

4. A hand propelled vehicle according to Claim 3, wherein the one wheel is an inner wheel.

5. A hand propelled vehicle according to Claim 4, wherein with at least two vehicle units connected together the braking element associated with the detached wheel set is aligned with and may act to brake a wheel of a wheel set of the vehicle unit to which it is connected.

6. A hand propelled vehicle according to Claim 4, wherein the brake element associated with the side frame to which the rear wheel set is fixedly mounted of one vehicle unit is coupled to the brake element associated with the brake element associated with the detached wheel set of another other vehicle unit, whereby engaging or disengaging the braking system on one vehicle unit engages or disengages the braking system on the other vehicle unit of the hand propelled vehicle.

7. A hand propelled vehicle according to Claim 6, wherein the coupling of the brake elements is a male/female coupling, one of the brake elements comprising the male part of the coupling and the other brake element comprising the female part of the coupling.

8. A hand propelled vehicle according to Claim 7, wherein the brake elements of the respective vehicle units are axially aligned.

9. A hand propelled vehicle according to any of Claims 6 to 8, wherein the brake elements are coupled together by moving one brake element substantially radially with respect to the other brake element.

10. A hand propelled vehicle according to any preceding claim, wherein each brake element is mounted on a lever, which lever is pivotally mounted on a side frame, and wherein the brake elements are engaged and disengaged by rotating the brake elements towards and away from the braked wheel.