GB2190496A - A device for indicating the speed of a vehicle equipped with a speed transducer - Google Patents

Abstract

A device for indicating the speed of a vehicle equipped with a speed transducer and having a movement sensor 2 which is arranged on the steering wheel 1.1, is connected via linkage 3 to a touch element 4 and is only activated by a deviation signal when there is a deviation from a signal of the speed transducer corresponding to the predeterminable speed, and moves the touch element 4, guided in a radial and outwardly open borehole in the steering wheel rim and lying flush with its outer contour, radially outward, projecting beyond the outer contour. Thus, the speed indicator provides the driver with an indication of speed 4 overshoots and undershoots independently of the speedometer. <IMAGE>

Description

SPECIFICATION A device for indicating the speed of a vehicle equipped with a speed transducer The invention relates to a device for indicating the speed of a vehicle equipped with a speed transducer.

On a largepartofthe road networkthere arespeed limits which must be observed. It is often difficultfor a vehicle driver not to exceed the maximum speed, in particular on downward inclines, in light traffic, at night etc. Usually, an optical check is kept on speed.

This necessitatesfrequentglances atthe speedometer, in which attention has to be diverted from road traffic. To counter this, acousticwarning systemswhich warn the driver bye gong orhorn when a maximum permissible speed is exceeded are already known as aids and even prescribed for example in a number of countries. In the case of these devices, it may be considered disadvantageous that -all vehicle occupants, in otherwords alsothe passengers who are not concerned, are disturbed, - the acoustic warning is only reasonable at more or less larger intervals, - acoustic communication to the driver is frequently occupied by radio or conversations with passengers.

Moreover, a checking device for the direction indicators of a two-wheeled vehicle is known (German Offenlegungsschrift 2,931,565), which generates a kinetic signal at a motorcycle handlebar grip made of elastomeric material, this signal acting in a pulsating manner in radial direction on the handlebargrip.Thissignal servesthe purpose of reliably informing the motorcycle rider, via his sense offeel, oftheswitched-on indicators.

The present invention is based on the object of providing, in addition to the speed indication always provided bythe speedometer, afurther device for indicating the speed, which gives the driverthe possibility of assessing his speed at any one moment without diverting his attention from the road traffic.

According to the present invention there is provided a device for indicating the speed of a vehicle equipped with a speed transducer, including a movementsensorwhich is arranged onthe steering wheel, and is connected to a touch element, the sensor being only activated by a deviation signal when there is a deviation from a signal ofthe speed transducer corresponding to a predeterminable speed, the touch element being guided in a generally radial and outwardly open borehole in the steering wheel rim and normally lying flush with the rim outer contour, and being movable radially outwardly to project beyond the outer contour in response to activation of said movement sensor by a said deviation signal.

Preferably, when the vehicle speed is less than the predeterminablespeed,the deviation signal results in a constant continuous activation of the movement sensor.

Preferably also, when the vehicle speed is greater than the predeterminable speed, the deviation signal results in an alternating activation ofthe movement sensor.

The movement sensor may comprise an electromagnet, the armature of which is operatively connected to the touch element.

In a preferred embodiment, the magnetic coil of the electromagnet is connected to the output of an electronic signal processor, to the input of which the signal of the speed transducer is supplied,the processor generating said deviation signal when there is a deviation from a signal corresponding to said predeterminabie speed at its output, such a signal at the output ofthe processor comprising a corresponding signal for activation of the electromagnet.

Preferably, a pressure switch is arranged in the movement sensor, which pressure switch can be activated radially inward from the armature upon manual activation of the touch element, and the pressure switch is electrically connected to the signal processor.

The movement sensor may be arranged on the steering wheel in the region of a steering wheel spoke.

For convenience of operation, the touch element is arranged in the second quadrant ofthe steering wheel, lying on the steering wheel rim and in the region of the fingers of the hand of the driver of the vehicle holding the steering wheel.

Preferably, the frequency of the deviation signal resulting in an alternating activation ofthe movement sensor is dependent on the amount of overshoot of the predetermined speed. Thus, owing to the fact that the driver is additionally offered an indication by his sense of feel, he does not have to continually turn his head to the speedometer, so that an impairment of safety is excluded; nor is he dependent on subjective features. Furthermore, the device also has the advantages -that it only reaches the responsible driver, -thatitcan beprogrammedtoanyspeeds, -that it continuously indicates speed overshoots and undershoots, and that the driver can, in a simple way, switch off from the information if thins is necessaryfor compelling reasons.

An embodiment ofthe invention will now be described in more detail by way of example with reference to the drawing, in which: Figure 1 shows the inventive device in diagrammatic representation and Figure2shows a detailed representation of the movement sensor.

The steering wheel 1 shown in Figure 1 and designed in a known way has a steering wheel rim 1 .1, a body 1.2 and a steering wheel spoke 1.3which comes out of the steering wheel hub 1.4, is connected to the body and is preferably arranged in the second quadrant of the steering wheel; at least one further steering wheel spoke - not shown - is then provided in the third quadrant. Arranged on the steering wheel spoke 1.3 there is then a movement sensor2, from which a linkage3comesoutand, passing through the body 1.2, extends as far as the steering wheel rim 1.1. Provided in the steering wheel rim 1.1 is a radially directed and outwardly open borehole 1.1.1, in which a touch element 4 is guided secure against twisting and is connected to the linkage 3.The touch element 4 and the linkage 3 are matched in such a way that the touch element4 terminates approximatelyflush with the outer contour 1.1.2 ofthe steering wheel rim 1.1, butstill has a certain distance from the bottom ofthe borehole 1.1.1. As is evident in conjunction with Figure 2, the movement sensor 2 consists of an electromagnet with a magnetic coil 2.1 and an armature 2.2, which is firmly connected at one end to the linkage 3. Atthe other end, the armature has a collar2.2.1, between which on the one hand and a housing part2.4ofthe movement sensor on the other hand a compression spring 2.3 supports itself, in ordertherebyto hold the armature in its rest position.The armature protrudes moreover, with its collar end, into a flange part 2.5 of the movement sensor 2 and rests in the latter on a thrustwasher 2.5.1, which in turn is held in its rest position against a stop 2.5.3 by means of a further compression spring 2.5.2.

Arranged in axiai alignmentto the armature 2.2 in the flange part 2.5 is a pressure switch 5, a movable element of which is turned toward thethrustwasher 2.5.1. Both the pressure switch 5 and the magnetic coil 2.1 are electrically connected to outputs 6.1 and 6.2 of a signal processing stage 6, the input 6.3 of which is connected to a speed transducer7 of known design. Both the speed transducer 7 and the signal processing stage 6may be components ofthe electronic speedometer in any case provided, in which case only the signal processing stage has to be extended in accordance with the operation described below.

The operating principle ofthe device is asfollows: If driver is driving his vehicle and does not wish to exceed a speed of for exampie50km/h, when at a speed of 50 km/h according to the speedometer indication, he briefly presses the touch element4 with one finger of the hand 8 holding the steering wheel.This causes the touch element4to be moved radially inward in the borehole 1.1.1 and with italso the linkage 3 and the armature 2.2, which presses the th rust washer 2.5.1, against the movable element of the pressure switch 5 via its collar 2.2.1. The pressure switch is thereby contacted and activates the signal processing stage 6, in which the speed travelled at the momentwhen the touch element4 is pressed - in other words 50 km/h - is then stored, available to it as signal of the speed transducer 7. lfthethus predetermined speed is maintained by the driver, there is no signal at the output 6.2 of the signal processing stage 6, i.e.,the magnetic coil 2.1 is not excited and armature, linkage and touch element remain in their rest position shown in the drawing.

Without looking atthe speedometer,the driver is therefore signalled that he is driving at the preselected speed by feeling the touch element lying flush with the outer contour ofthe steering wheel rim. If, on the other hand, the speed falls belowthe preselected and stored speed, the comparison of the signal ofthe speed transducerwith the stored signal causes the signal processing stage 6 to generate a deviation signal, as a result of which the magnetic coil 2.1 is permanently excitedvia the output6.2, with the effect that the armature 2.2 is attracted against the force of the spring 2.3 to the right in the drawing - and the touch element4 is moved via the linkage 3 radially outward, projecting beyond the outer contour 1.1.2 - which is shown in the drawing in broken lines.On feeling the touch element projected beyond the outer contour of the steering wheel rim, the driver is signalled thatthe speed travelled at that moment is less than the preselected speed. If, however, the driver has exceeded the preselected speed,the signal comparison likewise causes the signal processing stage to generate a deviation signal, but this time a pulsating signal, as a result of which the magnetic coil 2.2 is alternately excited and de-excited via the output 6.2, with the effectthat, via the armature and the linkage, the touch element 4 performs a vibrating movement which signals to the driver, when he feels it, a speed overshoot.

In afurtherdevelopmentofthe invention,the frequency of the pulsating deviation signal can be made dependent on the amount of overshoot of the preselected speed.

Aswitching-offofthe device is possible in the embodiment by keeping the touch element pressed a little longer, as a result of which the electronics of the signal processing stage are disconnected via the pressure switch. Renewed brief pressing of the touch element then reactivates the device with simultaneous storage ofthe speed then travelled at that moment.

It goes without saying that it is also possible to divide the touch element into several segments, each segment being assigned to a certain speed. In this case, the movement sensorwould have to be designed as a servo-motor which indirectly or directly moves the segments via a corresponding cam, the deviation signal generated at a particular corresponding speed serving as correcting variable for the servomotor and then, depending on the angle of rotation ofthe servomotor, then extending the corresponding segment or segments via the cam.

Claims (10)

1. A device for indicating the speed of a vehicle equipped with a speed transducer, including a movementsensorwhich is arranged on the steering wheel, and is connected to a touch element, the sensor being only activated by a deviation signal when there is a deviation from a signal of the speed transducer corresponding to a predeterminable speed, the touch element being guided in a generally radial and outwardly open borehole in the steering wheel rim and normally lying flush with the rim outer contour, and being movable radiallyoutwardlyto project beyond the outer contour in response to activation of said movement sensor by a said deviation signal.

2. A device according to claim 1, wherein, when thevehiclespeed is lessthan the predetermined speed, the deviation signal results in a constant continuous activation of the movement sensor.

3. A device according to claim 1, wherein, when the vehicle speed is greaterthan the predetermined speed, the deviation signal results in an alternating activation of the movement sensor.

4. A device according to claim 1, wherein the movement sensor comprises an electromagnet, the armature ofwhich is operatively connected to the touch element.

5. A device according to claim 4, wherein the magnetic coil ofthe electromagnet is connected to the output of an electronic signal processor, to the input of which the signal of the speed transducer is supplied, the processor generating said deviation signal when there is a deviation from a signal corresponding to said predetermined speed at its output, such a signal at the output of the processor comprising a corresponding signal for activation of the electromagnet.

6. Adevice accordingto claims40r5,whereina pressure switch is arranged in the movement sensor, which pressure switch can be activated radially inward from the armature upon manual activation of the touch element, and the pressure switch is electrically connected to the signal processor.

7. A device according to claim 1,whereinthe movement sensor is arranged on the steering wheel in the region of a steering wheel spoke.

8. A device according to claims 1 and 7, wherein the touch element is arranged in the second quadrant ofthe steering wheel, lying on the steering wheel rim and in the region of the fingers of the hand ofthe driver of the vehicle holding the steering wheel.

9. A device according to claim 3, wherein the frequency ofthe deviation signal resulting in an alternating activation of the movement sensor is dependent on the amount of overshoot of the predetermined speed.

10. A device for indicating the speed of a vehicle equipped with a speed transducer substantially as described herein with reference to and as illustrated in the accompanying drawings.