WO2000018639A1

WO2000018639A1 - Mechanical anti-block braking system, for a bicycle's wheel

Info

Publication number: WO2000018639A1
Application number: PCT/GR1999/000036
Authority: WO
Inventors: George Papadeas
Original assignee: George Papadeas
Priority date: 1998-09-30
Filing date: 1999-09-20
Publication date: 2000-04-06
Also published as: EP1064191A1; GR1003181B; AU5642599A

Abstract

Mechanical system that prevents the blocking of a bicycle's wheel upon braking, which, externally, reminds of a 'dynamo' and is installed on the bicycle in a similar manner. The main elements of this system are a main axis (1), two symmetrical parts rotating around it (3), one, or alternatively two inclined rings for the actinic slip of the aforementioned parts (4, 27), concentric with their rotation axis (1) and a brake pad (5), mechanically connected to the upper inclined actinic slip ring (4). The entire system can move axially, that is to the direction of the main rotation axis (1) thus achieving its function.

Description

TITLE

"Mechanical anti-block braking system, for a bicycle's wheel."

DESCRIPTION

The structure of the invention is made in reference to drawings 1 , 2, 3 and 4. Drawing 1 , shows the longitudinal section of the device according to arrow A-A, where we see the way it co-operates with the wheel of the bicycle. Drawing 2, shows the plan view of the entire system, where we can see the force offsetting wheel (22) mentioned below. Drawing 3, shows the profile of the entire system, where we can see the way the main mechanism is connected to the bicycle's frame, as well as the way it co-operates with the wire rope of the brake. Drawing 4, shows the detail concerning the co-operation of components (2) and (3), to which I will refer further on, as well as the oil holes of the mechanism. Drawings 5 and 6 refer to an alternative design. More specifically, drawing 6 shows the detail concerning the co-operation of components (2) and (3), in case the alternative solution of drawing 5 is adopted. The invention consists of the following systems:

A) The braking forces' offsetting system, which consists of a wheel (22), which is placed directly opposite to the pad, at the other side of the wheel and can roll freely on the rim. The purpose of this system is to prevent the disfigurement of the bicycle's wheel, which can be caused from the unilateral application of the braking force, on one side.

B) The main mechanism, which consists of a central longitudinal axis (1), constantly co-operating with the bicycle's wheel, thanks to the assistance of the elastic cone ring (18), located on one of its ends. The central axis (1 ), sets a pair of identical solids into gyration (3), thanks to the assistance of four dowel pins (2), which are vertically pasted to the central axis (1 ), "pierce" the solids (3) and transmit their gyrating motion to them. The dowel pins (2), are on the same vertical longitudinal level of the mechanism, which crosses the center of the main axis (1), while every two dowel pins, are on the same straight line. When the bicycle rider does not pull the brake, the gyration of the pair (3) occurs on a lateral level, stable as far as the axis (1) is concerned and, in such a way, that the gyrating solids (3), are always symmetrical to it. The radius of the cyclical gyration of the pair (3), may vary between two extremes (maximum and minimum), at the same time the pair gyrates. Thus, apart from gyration we also have an actinic slip of the gyrating solids (3), that is slip to the direction of their gyration radius. In this case, the nuts of the dowel pins (2) determine the end of the gyration radius of the solids (3), at its maximum. The hole on each solid (3), is bigger than the relevant diameter of the dowel pin (2), in order to ensure the free slip of the dowel pins (2), within the gyrating solids (3). The gyrating solids (3), have a flat base on their lower end, so that this base is constantly adjacent to a graduation of the diameter (ridge) of the central axis (1). However, alternatively, according to drawing 5, the lower base of the gyrating solids (3), may also be part of an adjoining surface of a truncated cone, which is concentric to their gyration axis, in order to be constantly adjacent to the lower inclined actinic slip ring (27). The upper part of the gyrating solids (3), is also an adjoining surface of a truncated cone, concentric to their gyration axis, in order to be constantly adjacent to the upper inclined actinic slip ring (4). The brake pad (5), is mechanically connected to the inclined actinic slip ring (4), in order to effect the braking of the wheel. All components (1), (2), (3) and (4), (alternatively (27) as well), are in the interior of a pipe, which is used as the shell of the device (6). There are also two roll ball bearings, used for the bearing of the central axis (1 ). The actinic ball-bearing (10), which is placed in the lower part of the mechanism, is stable in relation to the shell, while it permits the free slip of the central axis (1), along the longitudinal direction of the mechanism, an element of great importance to the system's functioning. The axial ball-bearing (9) is placed directly above the upper inclined actinic slip ring (4), and is the one receiving the entire braking force, as the central axis (1) slips along the direction of its length. Directly above the axial ball-bearing (9), component (5) is placed, which, in turn, is adjacent to the internal diameter of the shell (6), by free mounting, in order to ensure the unhindered axial slip of all components (1), (2), (3) and (4), and at the same time the bearing of the central axis (1 ), to the upper part of the mechanism. Lever (14), transmits the force of the wire rope to the central axis of the mechanism (1), whose articulation lies in the lower part of the mechanism's shell, as shown in drawing 3. The lower part of the central axis (1), ends at a conical surface, whose tip is adjacent approximately to the middle of the lever (14), that is between the articulation and the application point of the wire rope's force, as shown in drawing 3. The tip of the conical surface of the central axis (1) ensures the minimization of friction, as the central axis is gyrating while at the same time pressed by the lever (14). In the upper part of the shell, component (16) is placed, which is used for holding the braking return spring (17). The fastening of component (16) to the shell of the mechanism (6) is made with the assistance of three coupling bolts, which are placed at the circumference of the shell, as shown in drawing 2. Component (16) is also used for additional holding at the brake pad, upon braking. Finally, plates (11) and (12), are used for attaching the mechanism to the frame of the bicycle, as shown in drawings 2 and 3. The hole mechanism, operates as it's described below : The main axis of the mechanism (1 ) is set in motion directly from the bicycle's wheel, thanks to an elastic conical ring (18) at one of its ends, which is constantly adjacent to the bicycle's wheel, thus setting into gy- ration the two symmetrical bodies (3), at a gyration frequency much greater than that of the bicycle's wheel. (Apparently, this is due to the very big transmission relation between the two wheels). When the biker is not braking, the centrifugal force of the gyrating solids (3) is received entirely by the dowel pins (2), while the nuts, together with the rings, are used as the end of the radial movement, of these bodies. Upon braking the main axis of the mechanism (1), is pushed upwards thanks to lever (14), which is moved by the wire rope of the bicycle, as shown in drawing 3. The result is that component (5) also moves upward, meeting the rim of the wheel (26), thus effecting the braking of the bicycle. How- ever, in this case, the vertical braking force is multiple than the horizontal centrifugal force, due to the relatively small inclination of the contact surface of components (3) and (4), on the basis of the inclined plane principle. It has to be noted that if the speed of the bicycle is just 3 km/h the vertical braking force that the biker can produce, reaches up to 24 kp, a number which, in any case, can be considered as satisfactory. As the bicycle is braking, the centrifugal force is reduced, and, therefore, also its vertical, actinic component. Thus, after a given bicycle speed, the horizontal actinic component of the braking force, exceeds the centrifugal force, and as a result the gyrating bodies (3) "coil" to the center of the axis (1), the brake pad (5), starts descending, and this way the anti-blocking system is activated.

The adjusting screw (21), which lies at the lower part of the mechanism, adjusts the maximum braking travel, which is vital for the proper functioning of the system. After a given bicycle speed, when the brake pad ascends, because the gyrating solids (3) are deflected to a bigger orbit radius, due to the centrifugal force, there is a very small gap left between the pad and the rim (26). This gap is essential, because otherwise "the wheel would break by its own", that is without pulling the brake. Therefore, on one side this travel must always exceed the ascend of component (5), resulting from the "outwards" actinic motion of the solids (3) due to the centrifugal force, as well as the aforementioned gap. If this does not happen, then the "descent" of components (5) and (4), when the anti-blocking system is activated, as well as the aforementioned gap, would definitely exceed the maximum braking travel, resulting to its improper coverage, thus "rendering the brakes inoperative", each time the system would be activated. Moreover, the brakes would be useless when the bicycle would be stopped, since in this case the gyrating solids (3) would be "coiled" to the minimum radius of their orbit. However, on the other hand the maximum braking travel, must not be much longer, since there is the danger to immobilize the wheel and, in effect, render the entire system useless. Therefore, the maximum braking travel must include the following parts: 1 :The ascent of component (5) , resulting from the "outwards" actinic motion of the solids (3) apparently due to the centrifugal force.

2 : A travel corresponding to a residual braking force, big enough, in order to avoid the immobilization of the wheel, shortly before it is completely immobilized, when the additional force provided by the mecha- nism at that given moment, is practically nil.

3 : (If there is), a gap between the rim and the pad, when the ascend of components (4) and (5) has occurred, after a given bicycle speed. A way for realizing the invention is shown in drawings 2, 3, where the bearing plates (11), (12) of the mechanism's shell (6), are used for its attachment to the bicycle frame (25).

TABLE OF COMPONENTS

Claims

Mechanical system that prevents the blocking of a bicycle's wheels upon braking, which consists of the following parts:

A) The braking forces offsetting system, which consists of a wheel (22), placed directly opposite from the pad, on the other side of the bicycle's wheel and can move freely on the rim without sliding.

B) The main mechanism which consists of a central longitudinal axis (1), which set a pair of identical solid parts into gyration (3). The gyration of the pair (3) when the biker is not braking, is effected on a steady lateral level, in relation to the axis (1 ), at an angular velocity identical to that of the central axis (1) in such a menner that the gyrating solids (3), are always symmetrical to it. The radius of gyration of the pair (3), may vary between two extreme numbers (maximum and minimum) at the same time with its gyration. At the lower part of the gyrating solids (3) their base may constantly be tangent to the central axis (1), either in graduation of its ridge, or alternative, on an inclined actinic slip ring (27). The upper part of the gyrating solids (3) is always tangent to an inclined actinic slip ring (4). The pad (5) is connected to the inclined actinic slip ring (4), so that this move as a single body towards the di- rection of the central axis (1) and thus effecting the braking of the wheel. The invention is characterized by the following facts:

1) The angle of inclination of the inclined actinic slip rings (4), (27), to the lateral level of the mechanism, is bigger than the actinic slip friction angle between the rings and the gyrating solids (3), as well as between components (1) and (3), on the ridge of the axis (1). (In the alternative case).

2) The actinic slip friction factor between the gyrating solids (3) and the inclined actinic slip rings (4), (27), (and, alternatively, the ridge of the axis (1)), is less than 0.8 3) There is possibility for the axial shifting of all the components (1), (3), (4) and (5), (and, alternatively, (27) ), wherein these components may move across the length of the central axis (1).

4) The transmission relation between the gyration axis of the pair of solids (3) and the bicycle's wheel, is greater than 2 (TWO).

5) The minimum gyration radius of the mass center of each gyrating solid of the pair (3), is greater than 2mm

6) The mass of each gyrating solid of the pair (3), is greater than 2gr

7) The gyration axis of the force offsetting wheel (22), is immobile as far as the skeleton of the bicycle is concerned.