GB2026791A

GB2026791A - Bicycle-lighting system

Info

Publication number: GB2026791A
Application number: GB7917613A
Authority: GB
Original assignee: VARTA Batterie AG
Current assignee: VARTA Batterie AG
Priority date: 1978-05-19
Filing date: 1979-05-21
Publication date: 1980-02-06
Also published as: NL7903939A; FR2425972A1; IT7922833A0; FR2425972B1; CH637339A5; BE876363A; IT1112918B; DE2821854A1

Abstract

A bicycle-lighting system comprises an a.c. generator (1) adapted to be driven by frictional engagement with the tyre of a bicycle wheel, the generator (1) supplying current to lamps (7) through a rectifier (10) and a resistor (6). A rechargeable battery (2) is connected to the rectifier (10) through a reed switch (3) which is closed by a permanent magnet when the generator (1) is moved on its pivotal mounting on the bicycle into engagement with the tyre. The value of the resistor (6) is chosen so that at normal bicycle speed the generator (1) supplies current to the lamps (7) and also to the battery (2) whereas at slow speed or when the bicycle is stationary the lamps (7) are energised by the battery (2). All the component parts shown to the left of the vertical dash line of Figure 1 are combined in a unitary structure. <IMAGE>

Description

SPECIFICATION Bicycle-lighting system TECHNICAL FIELD OF THE INVENTION The invention relates to a bicycle-lighting system which incorporates lamps and an a.c.

generator for the supply of current to the lamps.

BACKGROUND ART Up to the present time, bicycle-lighting systems have been supplied with the necessary energy for their operation by an a.c. generator running simultaneously with the bicycle according to the dynamo-electric principle, the generator being driven from a bicycle wheel by an engaging and disengaging pinion drive.

In lighting systems driven in this manner, the electric energy produced depends directly upon the speed of the generator armature, and the brightness of the lighting thus depends directly upon the speed of travelling. At low speed (on uphill slopes, or resulting from an increased load or resulting from the cyclist's inefficiency or from traffic-conditioned circumstances) the lighting is inadequate and goes out altogether when the bicycle comes to a standstill, for example upon stopping at traffic signalling systems or for other reasons connected with the flow of traffic, with the result that the substantial danger to which cyclists are exposed in present day road traffic is even further increased.

DISCLOSURE OF THE INVENTION It is thus an object of the invention to provide a bicycle-lighting system which can constantly provide lighting even when the bicycle stops.

In accordance with the invention, this object is achieved in that the lamps are connected through a resistor to a series connection comprising a rectifier and a generator, a chargeable battery to which an operating switch is connected being connected in parallel with the series connection.

In one embodiment of the invention the operating switch is a reed switch which is inductively operable by a magnet.

In an advantageous construction of the lighting system according to the invention all of the current-supplying structural parts are combined in an integral structural unit.

In a particularly advantageous construction of the lighting system according to the invention, the a.c. generator is accommodated in a bottleshaped housing carrying at its upper end an energy-transmitting friction wheel. The housing is provided with a bipartite fastening arm or bracket with a hinge or pivot pin connecting the two parts and is secured to one of the two parts so as to swivel about its longitudinal axis. The battery and the reed switch are arranged in the interior of the housing and the non-swivelling part of the fastening arm secured to the housing carries a permanent magnet at a position remote from the hinge pin.

This advantageous construction has the particular advantage that the built-in, chargeable battery provided in the housing is automatically switched on as the a.c. generator moves to its operative position, that is to say, when the friction wheel is brought into contact with the side of a tyre. When the bicycle is taken out of operation the a.c. generator is swung back away from the side of the tyre so that connection between the battery and the lamps is prevented with resulting prevention of discharge of the battery.

Embodiments of a bicycle lighting system according to the invention are hereinafter described, by way of example, with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a circuit diagram of the lighting system according to the invention; Figure 2 is a perspective view of a first embodiment of apparatus forming part of the system according to the invention, the apparatus being cut-away to show certain components; Figure 3a is an elevational view, partly in section, of a second embodiment of apparatus forming part of the system according to the invention; and Figure 3b is a developed view of certain components of Figure 3a.

BEST MODES OF CARRYING OUT THE INVENTION Referring now to Figure 1, the two lamps 7, usually fitted on bicycles, are supplied with current from an a.c. generator 1 through a rectifier 10 and a resistor 6.

In addition, there is provided a battery 2 which is also connected to the lamps 7 through a switch 3 and the resistor 6. All of these component parts of the system except the lamps 7, are combined in a current-supply part SV.

The circuit operates as follows:- When the bicycle travels at normal speed, the generator 1 transmits its output to the rectifier 10 according to that speed of travel. However, the chargeable battery 2 is simultaneously also connected to the lamps 7 by the closed switch 3.

At normal speed the potential at point A of the generator 1 exceeds, however, the potential at point B of the battery 2. This difference between the potentials causes a current to flow from the rectifier 10 to the tapping or branching point to which the battery 2 is connected on one side and to which the lamps 7, through the resistor 6 are connected on the other side.

The rectified current coming from the generator is divided between the lamps 7 and the battery 2 according to the dimensioning of the resistor 6 with the result that the lamps 7 are supplied with current and also the battery 2 is charged.

When a bicycle travels at a very low speed or cpmes to a standstill, the potential in point A of the a.c. generator 1 drops to zero with the result that current then flows in the reverse direction from the battery 2 to the tapping or branching point. However, the rectifier 10 prevents division of the battery current which consequently flows through the resistor 6 to the lamps 7 to be supplied.

The resistor 6 is dimensioned so as to ensure optimum distribution betwen the lamp load current and the battery charging current during normal travelling. A battery 2 of relatively low capacity can be used, since the battery 2 generally needs to be operated for only short periods of time, for example by reason of traffic-conditioned stops. A 100 mAh battery permitting continuous operation of the whole lighting system for a period of from 10 to 1 5 minutes can be used in the illustrated embodiment.

As described previously, the direction of flow of the current changes frequently due to the constantly changing traffic conditions with the result that the battery 2 is alternately charged and discharged.

The switch 3 is provided to permit prevention of discharge of the battery 2 by the lamps 7 when the bicycle is taken out of operation.

Figure 2 shows that the combination of the components of the circuit is an integral structural unit in which the construction of the switch 3 is of particular importance.

The a.c. generator 1 is a conventional generator and is contained in the upper part of a housing 1 a on the top of which a friction wheel 12 is mounted for the purpose of transmitting energy from the side of a wheel tyre. The housing 1 a is connected to a bipartite fastening arm or bracket 4. The two parts of the arm 4 are interconnected by a spindle or hinge pin 4a permitting the housing 1 a to swivel about its longitudinal axis L.

The housing 1 a is of ample dimensions so that a hollow space for accommodation of the battery 2 and of the switch 3 is available below the a.c.

generator 1.

The battery 2 is constructed as a hollow cylinder containing in its interior the switch 3 which is a reed switch. The reed switch 3 is operated by a permanent magnet 5 which is mounted on that part of the fastening arm 4 which is secured to the housing la.

The permanent magnet 5 actsinductively upon the reed contact 3 thus making it possible for the reed switch to be operated as the housing 1 a swivels about the pivot 4a of the fastening arm 4. When the housing 1a is swivelled so that the friction wheel 12 presses against the wheel tyre, the contact of the reed switch 3 is closed and releasable latching means (not shown) hold the housing in this position so that the generator 1 may be driven.

The housing 1 a is made of a paramagnetic material in order to avoid impeding this switching operation. Moreover, the other eiectronic components of the circuit shown in Figure 1 may be accommodated in matching recesses provided at the periphery of the battery chamber as shown in Figure 3a.

Referring now to the embodiment of Figures 3a and 3b, in which similar reference numerals are used as for the corresponding parts of Figures 1 and 2, a battery 2 comprising a plurality of button cells is accommodated centrally in a housing 1 b forming a lower extension of the a.c.

generator housing 1 a. A hollow space in the shape of an annulus or ring cylinder between the battery 2 and the housing ib contains a reed switch 3, a resistor 6 and the diodes of a rectifier 10. The annular hollow space is limited at the top by an insulating bush or sleeve 11. The reed switch 3 is within the radius of action of the permanent magnet 5 so that the reed switch can be closed or opened by swivelling the housing 1a.

The arrangement of the structural elements 3, 6 and 10 in the annular hollow space is shown in a development of the insulating bush or sleeve 11 in Figure 3b.

The battery circuit opening and closing and the tyre engaging and disengaging arrangement including the permanent magnet 5 and releasable latching means, are as described with reference to Figure 2. In this embodiment the releasable latching means is denoted by reference 13 in Figure 3a.

The electric connections for the lamps 7, denoted by plus and minus signs, are brought out through the bottom of the housing 1 b.

The system according to the invention has the advantage of being not only space-saving, but of permitting the lighting system to be switched automatically on and off when the housing of the current supply start is swung into and removed from its operating position with respect to the wheel tyre. The known method, in which the a.c.

generator 1 is switched on and off by tilting the dynamo, applies also to the construction according to the invention in which the battery 2, also, can be switched on and off by the same process. The invention thus has the advantage that operation of the lighting system is not made more difficult despite the more elaborate technique employed in the operation of the lighting system. The stop or rear light fed with current by the battery 2 lights up instantaneously as the user of the bicycle moves the dynamo housing to its operating position and an additional switch (not shown) is closed.

Without necessarily limiting the scope of the invention claimed preferred embodiments of the invention may be summarised as follows:- 1. A bicycie-lighting system which comprises lamps and an a.c. generator for supplying current to the lamps, characterised in that the lamps (7) are connected to a series connection consisting of a rectifier (10) and a generator (1) through a resistor (6), and a chargeable battery (2) connected to an operating switch (3) is connected in parallel with said series connection.

2. A bicycle-lighting system according to Summary 1, characterised in that the operating switch (3) is a reed switch inductively operable by a magnet.

3. A bicycle-lighting system according to Summary 1, characterised in that all of the current-supplying structural parts (SV) are combined in an integral structural unit.

4. A bicycle-lighting system according to any one of Summaries 1 to 3, in which the a.c.

generator is arranged in a bottle-shaped housing carrying on its upper end an energy-transmitting friction wheel, and in which the housing is provided with a bipartite fastening bow or bracket possessing a hinge or pivot pin, the housing being secured to the fastening bow so as to swivel about its longitudinal axis, characterised in that the battery (2) and the reed switch (3) are arranged within the housing and the non-swivelling part of the fastening bow (4) carries a permanent magnet (5) externally of its swivel axis hinge or pivot pin.

5. A bicycle-lighting system according to Summary 4, characterised in that the battery (2) is constructed as a hollow cylinder of which the longitudinal axis coincides with the longitudinal axis of the housing (1 a), and the reed switch is arranged internally of the hollow cylinder.

6. A bicycle-lighting system according to Summary 4, characterised in that a multicell, cylindrical battery (2) is arranged in the interior of the housing, a space having the shape of an annular or ring cylinder being available between the battery (2) and the housing ( 1 b), in which space the reed switch (3), the resistor (6) and the diodes of the rectifier (10) are arranged.

Although reference numerals have been used in the appended claims to improve the intelligibility of these claims, it is expressly stated that these reference numerals should not be construed as limiting the claims to the constructions illustrated in the accompanying drawings.

Claims

1. A bicycle-lighting system which comprises at least one lamp (7), and an a.c. generator (1) for supplying current to the lamps (7), and a rectifier (10) disposed between the generator and the lamp (7), characterised in that the lamp (7) is connected to the rectifier (10) through a resistor (6); the lamp (7) and the resistor (6) form a first series circuit; a rechargeable battery (2) is connected to the rectifier (10) through a control switch (3); and the battery (2) and the control switch (3) form a second series circuit in parallel with the first series circuit.

2. A system, according to Claim 1, characterised in that said controi switch (3) is a reed switch and the system includes a permanent magnet (5) for operating the reed switch (3) by magnetic induction.

3. A system, according to Claim 1 or Claim 2, characterised in that all the component parts of the system except the lamps (7) and electric cables connected thereto are combined in a unitary structure.

4. A system, according to Claim 2 or Claim 3, characterised in that the a.c. generator (1) is arranged in a bottle-shaped housing (1a) carrying on its upper neck end a drive wheel (12) for frictional engagement with the tyre of a wheel of the bicycle, the housing (lea) having a two-part mounting arm or bracket (4), said two parts being interconnected by a hinge or pivot pin (4a) and one of said parts being secured to the housing (lea) thus enabling the housing (1 a) to be swivelled about its longitudinal axis when it is mounted on the bicycle so that said wheel (1 2) can be engaged with and disengaged from the tyre, and said housing (1a) or an extension (1 b) of said housing (lea) contains said reed switch (3) and said battery (2) and said one of said two parts of the mounting arm or bracket (4) carries the permanent magnet (5) at a position remote from the axis of said hinge or pivot pin (4a).

5. A system, according to Claim 4, characterised in that the battery (2) is constructed as a hollow cylinder having its longitudinal axis coincident with the longitudinal axis of the housing (1a) and the reed switch (3) is arranged internally of the cylinder.

6. A system, according to Claim 4, characterised in that the battery (2) is a cylindrical battery consisting of a stack of individual cells, the battery (2) being arranged centrally within the housing extension (1b) and defining between itself and the inner wall of the housing extension (1 b) an annular space, and said resistor (6), said reed switch (3) and diodes 110) comprising said rectifier are arranged in said annular space.

7. A system, according to any one of Claims 4 to 6, adapted to operate such that, in use, when said wheel (12) is engaged with the tyre said switch (3) is closed and when said wheel (12) is disengaged from the tyre said switch (3) is opened.

8. A bicycle lighting system constructed and adapted to operate substantially as hereinbefore described with reference to, and as illustrated in, Figures 1 and 2 or Figures 1, 3a and 3b, of the accompanying drawings.