GB1580793A - Braking means for pedal actuated vehicles - Google Patents

Description

(54) BRAKING MEANS FOR PEDAL ACTUATED VEHICLES (71) We, C D T DESIGN CONSUL TANTS LIMITED, a British Company, of Flat F1, 37 Dyott Road, Moseley, Birmingham B13 9QZ, do hereby declare the invention for which we pray that a Patent may be granted to us and the method by which it is to be performed to be particularly described in and by the following statement: This invention relates to braking means for pedal actuated vehicles.

According to the present invention we proc vide a braking means for a pedal actuated vehicle conaprising: a first rotatable element and a second rotatable element; a formation between said first and said second rotatable elements, which has engaged and disengaged positions, the position of said formation being determined by the direction of rotation of one of said rotatable elements so that when the formation is in the engaged position the two rotatable elements are caused to rotate together, and when the formation is in the disengaged position said one rotatable element can rotate relative to the other; said formation comprising at least one rolling element disposed in a cowoperating slot which at one end has a dimension larger than that of the rolling element to permit rotation of the rolling element and, at the other end, a dimension smaller than that of the rolling element, a control device for moving the formation to the disengaged position during forward rotation of said one rotatable element with respect to the other rotatable element, wherein the control device is arranged so that backward rotation of said one rotatable element with respect to the other causes said formation to move to the engaged position; a braking force transmitting system coupled to a pair of braking force transmitting cables; means for securing said one of said rotatable elements to a rotatable drive member of the pedal actuated vehicle; and means connecting the other of said rotatable elements to said braking force transmitting system.

Conveniently, the control device is actuatable by an actuating member which permits a predetermined rotation of the one rotatable element in a reverse direction before actuating the control device to permit the rolling elements to move towards the locking position.

It is desirable that a release plate be operatively connected to said one rotatable element so that when it is rotated in a forward direction the release plate causes the rolling elements to be released from the engaged position. This arrangment greatly facilitates the initial rotation in the forward direction particularly when the rolling elements have been forced against rhe bearing surfaces of said slots to such an extent that they would not release themselves without the intervention of mechanical releasing means.

If desired the control device may be actuated by separate or auxiliary means such as manually operable actuating means.

Referring to the accompanying drawings: Figure 1 is an exploded perspective view of part of a braking means according to the invention; and Figure 2 is a diagrammatic side elevation of a braking means showing part of a brake force transmitting system.

The device shown in Figure 1 comprises an actuator plate 6 having a flange 6a which forms a bearing surface with rollers 14, a cam plate 8 having cam surfaces for receiving the rollers 14, a release plate 9, a retainer 10, a pedal crank plate 11 and a delay plate 12.

The actuator plate includes a cyLindrical flange 6a and a projecting portion 6b having an aperture 6c whereby an operating lever may be connected thereto.

A cam plate includes six cam surfaces 8a, detail of the shape of which is shown in the inset. The cam plate is also provided with three radially distrilbuted apertures 8d for receiving retaining threaded elements 13 which are riveted in apertures 8d.

It will be seen from the drawing that when the cam plate 8 is assembled with the actuator plate 6 such that rollers 14 are disposed between the cam surfaces 8a and the flange 6a rotation of the cam plate 8 relative to the actuator plate will be permitted in a clockwise direction, but when it is rotated in an anti clockwise direction the rollers will be trapped between the surfaces 8a and flange 6a causing rotation of the actuator plate 6.

The release plate 9 includes a series of apertures 9e and three slots 9d. The plate 9 is of annular form and includes inner projections 9b which control the positions of the rollers 14 between the respective bearing surfaces the rollers 14 being biassed towards the projections 9b by springs 15. Thus, the release plate 9 operates in the manner of a cage for retaining the rollers 14 and the position of this cage relative to the cam plate 8 will determine whether or not any force is transmitted to the actuator plate 6. Threaded members 17 are riveted in the apertures 9e.

The brake retainer comprises an annular plate 10 having an inturned portion 10b.

The pedal crank plate 11 comprises an annular plate having an inner diameter 11b of a size to Suit the size of the pedal crank boss and having three radially distributed apertures lld. A portion of the chain wheel is shown diagrammatically at 16.

The brake delay plate includes three radially distributed apertures 12d and three radially distributed slots 12e.

The various plates are assembled as shown in Figures 1 and 2 with bolts 13 passing through the apertures 8d, slots 9d, apertures 11d and apertures 12d in the plates. The bolts 17 pass through the apertures 9e and the slots 12e.

The device is, in use, attached to the chain wheel 116 of a bicycle so that the pedal crank plate rotates with the chain wheel 16. During normal forward running of the bicycle the pedal crank plate causes the delay plate, the brake release plate and the cam plate to rotate in the same direction, the rollers being disposed within the cam surfaces 8a in the disengaged position which does not cause any rotation of the actuator plate. When the chain wheel of the bicycle is rotated in the reverse direction by the pedals, however, the pedal crank plate again rotates therewith and by virtue of the bolts 13 the delay plate 12 is caused to rotate therewith.

The first portion of the movement is taken up by the slots 12e which then after a short period of time cause the brake release plate 9, by virtue of rhe threaded members 17 in the apertures 9e, to rotate in the reverse direction and the projections 9b move the rollers towards the looking position between the cam surfaces 8a and the flange 6a on the actuator plate 6. The actuator plate is thus caused to rotate and this rotation may be used to operate a brake system for the bicycle.

It will be appreciated that movement of the chain wheel in the forward direction will cause the respective plates to adopt their original position permitting free movement of the chain wheel and associated plates relative to the actuator plate.

The device described above is particularly convenient for use as a braking device on a bicycle, the braking action being caused by back-pedalling. The braking action is particularly reliable and the arrangement described above permits the bicycle to be wheeled forwards or backwards without engagement of the rollers with the bearing surfaces taking place and is also effective in producing a positive release of the rollers from the engaged position to facilitate the bicycle being pedalled after a braking action has taken place.

A brake force transmitting system is illustrated in Figure 2.

The force transmitting system 20 is shown fixed by means of a bracket 21 to a frame member of a bicycle 22. The actuator plate 6 is shown in solid lines in the "brake-off" position and in dotted lines in the "brake-on" position.

The portion 6b of the actuator plate 6 is pivotally connected to a connecting arm 23 which in turn is pivotally connected to a connecting means 24. The connecting means 24 is supported on fixed means 25 by an elongate rod 26 pivotally attached to the connecting means 24 at a position 27. Slots 28 and 29 receive the bosses at the end of Bowden type cables which are used for operating the front and rear brakes respectively of the bicycle.

When the actuating element is moved to the "brake-on" position the connecting arm 23 causes the connecting means 24 to move relative the fixed means 25 thereby actuating both front and rear brakes via the cables connected at 28 and 29.

The system is capable of seff-adjustinent by virtue of the provision of washer 30 which is of a type which permits movement of the washer 30 relative to the elongate rod 26 in one direction but prevents such relative movement in the opposite direction. Thus, the washer 30 acts as an abutment against the fixed means 25 and automatically adjusts the position of the connecting means 24 relative thereto to compensate for the condition of the brake pads.

As shown in Figure 2 connecting arm 23 is pivoted to the connecting means 24 at a position which is offset towards the connection 28. This arrangement provides for a greater braking force to be applied to the cable attached at 28 than that applied to the cable attached at 29, the precise position being predetermined to give the desired distribution of brain effect.

The slot 31 in the base of the connecting means 24 allows limited angular movement of the arm 23 to provide a minimum fail safe deflection of alignment in the event of failure of one brake, brake mechanism or brake cable or casing.

The system described above is particularly reliable in operation and has a very convenient self-adjustment feature. In addition it also possesses a safety feature in that should one of the brake operating cables break the connecting means 24 will pivot by virtue of the tension applied by the connecting arm 23 and thereby cause the other brake to be operated.

WHAT WE CLAIM IS:- 1. A braking means for a pedal actuated vehicle comprising: a first rotatable element and a second rotatable element; a formation between said first and said second rotatable elements, which has engaged and disengaged positions, the position of said formation being determined by the direction of rotation of one of said rotatable elements so that when the formation is in the engaged position the two rotatable elements are oaused to rotate together, and when the formation is in rhe disengaged position said one rotatable element can rotate relative to the other; said formation comprising at least one rolling element disposed in a co-operating slot which at one end has a dimension larger than that of the rolling element to permit rotation of rhe rolling element and, at the other end, a dimension smaller than that d the rolling element, a control device for moving the formation to. the disengaged position during forward rotation of said one rotatable element with respect to the other rotatable element, wherein the control device is arranged so that backward rotation of said one rotatable element with respect to the other causes said formation to move to the engaged position; a braking force transmitting system coupled to a pair of braking force transmitting cables; means for securing said one of said rotatable elements to a rotatable drive member of the pedal actuated vehicle; and means connecting the other of said rotatable elements to said braking force transmitting system.

2. Braking means according to claim 1 in which the rolling element(s) are biassed towards the smaller dimension of the slot(s).

3. Braking means according to claims 1 or 2 in which the control device is actuatable by an actuating member which permits a predetermined degree of rotation of said one rotatable element with respect to the other rotatable element before the rolling element(s) move towards the engaged position.

4. Braking means according to any of claims 1 to 3 in which the force transmitting system comprises a fixed element, an arm pivoted to a connecting means, said connecting means being secured to an elongate rod, said connecting means and said rod being movable with respect to said fixed element in response to movement of said arm, said connecting means having a pair of slots to receive and retain the ends of force transmitting cables.

5. A braking means substantially as herein described with reference to and as shown in the accompanying drawings.

6. A pedal actuated vehicle provided with a braking means as claimed in any of claims 1 to 5.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. also possesses a safety feature in that should one of the brake operating cables break the connecting means 24 will pivot by virtue of the tension applied by the connecting arm 23 and thereby cause the other brake to be operated. WHAT WE CLAIM IS:-

1. A braking means for a pedal actuated vehicle comprising: a first rotatable element and a second rotatable element; a formation between said first and said second rotatable elements, which has engaged and disengaged positions, the position of said formation being determined by the direction of rotation of one of said rotatable elements so that when the formation is in the engaged position the two rotatable elements are oaused to rotate together, and when the formation is in rhe disengaged position said one rotatable element can rotate relative to the other; said formation comprising at least one rolling element disposed in a co-operating slot which at one end has a dimension larger than that of the rolling element to permit rotation of rhe rolling element and, at the other end, a dimension smaller than that d the rolling element, a control device for moving the formation to. the disengaged position during forward rotation of said one rotatable element with respect to the other rotatable element, wherein the control device is arranged so that backward rotation of said one rotatable element with respect to the other causes said formation to move to the engaged position; a braking force transmitting system coupled to a pair of braking force transmitting cables; means for securing said one of said rotatable elements to a rotatable drive member of the pedal actuated vehicle; and means connecting the other of said rotatable elements to said braking force transmitting system.

2. Braking means according to claim 1 in which the rolling element(s) are biassed towards the smaller dimension of the slot(s).

3. Braking means according to claims 1 or 2 in which the control device is actuatable by an actuating member which permits a predetermined degree of rotation of said one rotatable element with respect to the other rotatable element before the rolling element(s) move towards the engaged position.

4. Braking means according to any of claims 1 to 3 in which the force transmitting system comprises a fixed element, an arm pivoted to a connecting means, said connecting means being secured to an elongate rod, said connecting means and said rod being movable with respect to said fixed element in response to movement of said arm, said connecting means having a pair of slots to receive and retain the ends of force transmitting cables.

5. A braking means substantially as herein described with reference to and as shown in the accompanying drawings.

6. A pedal actuated vehicle provided with a braking means as claimed in any of claims 1 to 5.