GB2113443A - Indicators - Google Patents

Abstract

An indicator, such as a label 5 displaying information, is readily detachable and interchangeable by magnetic forces. As shown, the label 5 is located by a pin 7 when applied to a supporting disc 4 which is rotatable with a knob 2 of a selector device. The supporting disc 4 may be formed of a flexible magnetic sheet 9 of ferromagnetic material attached to an aluminium plate 10 by an adhesive 11. The label 5 comprises magnetised material. Alternatively, the replaceable label (24) may display a graduated scale (23) for a slider (20). <IMAGE>

Description

SPECIFICATION Indicator Indicators such as labels are commonly used in connection with knobs or the like on electronic equipment which select ranges of power, voltage current, etc. and this is usually done by permanently marking different discrete positions which can be selected by moving the knobs. It is difficult to provide unambiguous information if the effective range value is alterable elsewhere; for example, an input signal may be subject to prescaling by different selectable values, so that the label applied to a knob may be true only for one particular prescaling value.

Alternatively a normalised factor can be provided on a label so that an operator himself can multiply by an appropriate amount to give a true value.

This difficulty could be largely overcome by the provision of interchangeable labels, each label being appropriate to a particular prescaling value, but although attractive in principle, interchangeable labels are cumbersome to use; in that time, care ans possibly special tools are needed to correctly mount and orient the label relative to the knob etc. The present invention seeks to provide an improved indicator in which these difficulties are reduced.

According to this invention an indicator for use with a selector device comprises a magnetic sheet material having location means so as to ensure correct orientation relative to the device; and label means for presenting visual information to an operator indicative of a selected position of the selector device.

- Conveniently the label means is secured to the magnetic sheet material by means of an adhesive, and preferably the magnetic sheet material is, itself, flexible.

The indicator is particularly suitable for use with a control knob or slider or the like, in which a control member is movable relative to a panel of some kind.

The label can be mounted on the panel, in which case the position of the knob or slider is used to indicate the location of the label which carries the relevant information, or the label can be mounted on the knob or slider so as to be movable therewith relative to a datum mark on the panel.

The invention is further described by way of example with reference to the accompanying draw ings in which, Figures 1 and 2 show plan and section views of an indicator in accordance with this invention, Figure 3 shows a section through part of the indicator in greater detail, and Figures 4 and 5 respectively show a plan and section views of an alternative indicator in accord ance with the invention.

The need for such an indicator can arise in connection with electronic test equipment which is required to accept input signals having widely differing amplitudes. It is usual to perform tests upon the signal by adjusting a control device either to attenuate or amplify a signal by a predetermined amount, or to select some other function, and it is usual for an indication to be provided to an operator so as to indicate in some way the numerical value of the parameter which he has selected. However, if the nature or the level of the signal is modified in some way elsewhere, the numerical values displayed on the selector may no longer be true and it may be necessary to apply a conversion factor to them or possibly to disregard the numerical values altogether.Such a requirement can arise where different input sensitivities can be selected depending on the level of an input signal or to enable different functions to be tested. Then, when the input level alters, it is necessary to adopt a new set of numerical values for the indicator.

The invention enables these numerical values to be readily changed at will in a very simple yet effective manner which requires no skill on the part of the operator.

Referring to Figures 1 and 2, part of the front panel 1 of an electronic test equipment is shown. A rotatable control knob 2 is mounted on the front panel 1 by means of a rotatable shaft 3, which passes through and is secured to the front panel 1. The rotatable knob 2 carries a rotatable support disc 4 which is permanently attached to the knob 2 and the shaft 3, so as to rotate therewith. A detachable label 5 is mounted on top of the support plate 4 and is provided with a locating aperture 6, which cooperates with a pin 7 projecting from the support plate 4. This ensures that the label 5 is exactly and correctly orientated with respect to the shaft 3.

The label 5 carries numerical values on its front surface and positioned around its perimeter, so that the numerical value adjacent to a datum mark 8 indicates the current setting of the instrument.

The numerical values carried by the label 5 may be correct for only one setting of the instrument, and when that setting is altered, the label 5 is simply detached from the support plate 4 and a replacement label mounted in its place. The back plate 4 is made of a ferro-magnetic material and the label 5 includes a magnetised material so that the label is retained upon the back plate firmly by magnetic force.

The construction of the label 5 is illustrated in more detail in Figure 3. A circular apertured disc of flexible magnetic sheeting 9 is secured to a thin, but stiff, aluminium plate 10 by means of an adhesive 11 carried by the sheet 8. The magnetic sheet 9 and the disc 10 both contain a control aperture to enable the label 5 to pass over the knob 2, but the plate 10 is provided with an additional indent 6 positioned with precision so as to co-operate exactly with the pin 7.

The magnetic material is a flexible sheet containing internal magnetisation. Its outer surface is provided with a suitable adhesive during manufacture and it is merely necessary to firmly press an aluminium disc against the adhesive to obtain a strong and long lasting bond. The information is formed on the outer surface 12 of the aluminium disc by conventional means, i.e. by painted or printed symbols.

In Figures 1 and 2, the information is carried by the rotatable knob which rotates relative to the fixed datum mark 8. However, this need not necessarily be so, and an alternative form of the invention is shown in Figures 4 and 5. A slider 20 is slidable up and down along a narrow slot 21. The slider 20 carries a datum mark 22, which is adjacent to a graduated scale 23, which is carried by a replaceable label 24.

The slot 21 is formed in a front panel 25 which also carries two registration pins 26 and 27, which co-operate with two apertures positioned and formed with precision through thickness of the label 24. The label 24 can be readily removed and replaced by a label carrying a different graduated scale by simply pulling to overcome the magnetic attraction force. The label 24 is a multi-layer structure which is exactly analogous to the label 5 described with reference to Figure 3.

Labels of this kind can be attached to a front panel and removed a very large number of times without damaging the label or the front panel, whilst enabling an attractive and professional appearance to be presented to an operator.

Claims (6)

1. An indicator for use with a selector device includes a magnetic sheet material having location means so as to ensure correct orientation relative to the device, and label means for presenting visual information to an operator indicative of a selected position of the selector device.

2. An indicator as claimed in claim 1 and wherein the label means is secured to the magnetic sheet material by means of an adhesive.

3. An indicator as claimed in claim 1 or 2 and wherein the magnetic sheet material is, itself, flexible.

4. An indicator as claimed in any of the preceding claims and which is mountable on a movable selector member.

5. An indicator as claimed in any of claims 1 to 3 and wherein it is mountable on an instrument panel.

6. An indicator arrangement substantially as illustrated in and described with reference to the accompanying drawings.

6. An indicator for use with a selector device and which is substantially as illustrated in and described with reference to any of the accompanying drawings.

New claims or amendments to claims filed on 12th Nov1982 Superseded claims 1 to 6 New or amended claims:

1. An indicator arrangement including a selector device having a movable portion; and an indicatior plate associated therewith; the indicator plate incorporating magnetic material and being detachably magnetically mounted in a precisely predetermined position relative to said selector device, and having location means so as to ensure its correct orientation and position with respect to said selector device, the indicator plate also having means for presenting visual information to an operator indicative of a selected position of the movable portion of the selector device.

2. An indicator arrangement as claimed in claim 1 and wherein said indicator plate consists of a magnetic sheet material and a support plate which are secured together by means of an adhesive.

3. An indicator arrangement as claimed in claim 2 and wherein the magnetic sheet material is, itself, flexible.

4. An indicator arrangement as claimed in any of the preceding claims and wherein the indicator plate is mounted on the movable portion of said selector device.

5. An indicator arrangement as claimed in any of claims 1 to 3 and wherein the indicator plate is mounted in a fixed position adjacent to said movable portion of said selector device.