EP0077173A1

EP0077173A1 - Multiple sign

Info

Publication number: EP0077173A1
Application number: EP82305311A
Authority: EP
Inventors: Paul Douglas Tyers
Original assignee: GEC GLAUDGEN Ltd
Current assignee: GEC GLAUDGEN Ltd
Priority date: 1981-10-07
Filing date: 1982-10-06
Publication date: 1983-04-20
Also published as: GB2110452A

Abstract

In a roller blind sign in which the ends of a web (1) of flexible material carrying a plurality of display items are carried by respective supporting rollers (2,3), the rollers are mechanically coupled to each other for enabling them to be rotated in unison by a common reversible drive, and the part of the web between the rollers passes over a movable jockey roller (8) which is biased in a direction which ensures that the web is maintained under tension throughout the whole of its transference from one supporting roller to the other, thereby compensating for changes in the length of that part of the web due to changes in the effective diameters of the rollers as the web is transferred.

Description

This invention relates to signs of the kind which incorporate a plurality of display items, for example in the form of information, instruction, pictures or other matter, and in which a selected item can be brought to a display position to permit it to be viewed; the invention relates more particularly to such signs in which the display items are carried by a web of a suitable flexible material, the ends of which are carried by respective supporting rollers, these signs being commonly known in the art as roller blind signs and will hereinafter be referred to as such.
When only a small number of individual display items is required means are commonly provided for rolling the part of the web carrying items already displayed onto one of said supporting rollers, the part of the web carrying items still to be displayed being accommodated on the other roller, which is usually provided with a spring for the purpose of reversing the movement of the web when required. In such cases it is general to provide a source of power which rotates the first roller in one direction until all the items have been displayed; that roller is subsequently released and the stored energy in the spring returns the system to its starting point. When, however, the web carries a large number of display items it has been customary to provide two sources of power, one for each roller, and to provide a mechanism which changes the source of power from one roller to the other.
In a roller blind sign of this latter type it is obvious that if a large number of individual display items is involved the total length of the necessary web will be appreciable, and when wound from one roller to the other there will be wide variations of the effective diameters of the two rollers according to the length of web which happens at any moment to be wound onto the rollers.
Under these conditions it will be seen that one revolution of the roller with the effective large diameter will cause a far greater movement of the web than will occur with a similar revolution of the other roller, and accordingly the mechanics of the drive mechanism to move the web in either direction tends to become complicated. It follows that if the two supporting rollers could be driven in unison i.e at the same, or a uniformly related, speed irrespective of variations in their effective diameters the design and construction of the drive mechanism of a sign of the type concerned would be greatly simplified.
However it will also be seen that changes in the effective diameters of the rollers as they are rotated will introduce a further problem if they are driven at the same speed, because the length of the web between them will change with each revolution. Thus when the web is equally disposed on the two rollers the length of the free section of the web will be a maximum, gradually decreasing on rotation of the rollers until substantially the complete length is located on one or other of the rollers according to the direction of rotation.
An object of the invention is to provide a form of roller blind sign incorporating a simple drive system for the supporting rollers, but which provides an effective solution to this latter problem.
According to the invention a roller blind sign incorporates means mechanically coupling the supporting rollers to each other for enabling them to be rotated in unison by a common reversible drive means for bringing a selected one of the display items in the display position, and a movable jockey roller over which the part of the web between the supporting rollers passes, which jockey roller is biased in a direction which maintains the web under tension as it is transferred from one supporting roller to the other.
The use of an appropriately biased jockey roller ensures that the web is held under a suitable degree of tension throughout the whole of its transference from one supporting roller to the other, thereby compensating for changes in the length of the part of the web between the rollers due to the differences in the effective diameters of these rollers as the web is transferred.
Biasing of the jockey roller is preferably effected by spring means, although for some applications of the invention, depending upon the orientation of the sign, it may be provided by gravity.
The supporting rollers are preferably of substantially the same diameter, and the coupling between them is such as to cause these rollers to be rotated at identical angular velocities. The drive means may, for example, be connected or connectable to drive one roller, with that roller coupled to the other by means of interengaging pinions. Thus the coupling may be provided by pinions fixed to shafts drivingly supporting the rollers, and either engaging each other directly or through one or more intermediate pinions. However other forms of coupling may be employed. Thus, instead of pinions, the rollers may be coupled by a chain and sprockets, or by a timing belt and associated pulleys.
In an alternative arrangement the drive means may be applied to an intermediate rotatable member similarly coupled to both supporting rollers.
The drive means may comprise a manually operable handle or hand-wheel, fitted or capable of being fitted to an extension of the shaft of at least one of the rollers, or to the shaft of a said intermediate rotatable member where provided.
Preferably, however, the drive means comprises a reversible electric motor coupled to the shaft of at least one of the supporting rollers, or to the intermediate rotatable member where provided, through a reduction gear system. Such an arrangement enables the sign to be controlled remotely to change the display item on view at the display position. Means may then be provided generating position indicator signals indicative of the position of the web, and display means at the remote control position for indicating which of the display items is in the display position.
For example each display item may have associated with it on the web, or means movable therewith, a position indicator corresponding to that item, the sign incorporating a detector located adjacent the path of the position indicators on movement of the web and arranged to generate a position indicator signal appropriate to a respective display item when that item approaches or reaches the display position.
Means responsive to said position indicator signals may also be provided for automatically arresting the web with a selected display item in the display position.
In order that the invention may be better understood two different embodiments of it will now be described in detail with reference to Figures 1 to 4 of the accompanying schematic drawings in which

- Figures 1 and 2 illustrate diagrammatically a front view and a side view of the operative parts of one roller blind sign in accordance with the invention, and
Figures 3 and 4 illustrate, also diagrammatically, similar views of a second sign.

Referring first to Figures 1 and 2 the sign illustrated comprises a web 1 of any suitable flexible material such as a fabric or a plastic, the ends of which are firmly fixed to two similarly dimensioned supporting rollers 2, 3 respectively, the web having, disposed along its length, a plurality of different indicia required to be individually displayed at a display position represented by the broken line D (Figure 1). The rollers 2, 3 are mechanically coupled by intermeshing identical pinions 4, 5 attached to shafts 12, 13 drivingly supporting the rollers 2, 3.
In order to display the signs, the web 1, after it leaves the supporting roller 2, passes over a first idler roller 6 mounted at a suitable distance above the roller 2, depending upon the height of the matter required to be displayed, the web then passing over a further idler roller 7 before reaching the other supporting roller 3. However, instead of extending directly between the two idler rollers 6, 7, the web is passed under a jockey roller 8 which is free to move vertically and take up the slack existing between the jockey rollers 6, 7 either by the action of gravity or preferably by means of a pair of springs as shown at 9.
In order to change the matter displayed it is only necessary to rotate either of the supporting rollers 2, 3 for which purpose it is convenient to provide one of the roller shafts 12, 13 with an extension, as shown at 10, to which suitable drive means is, or is arranged to be, connected. It will be seen that as the two rollers 2, 3 are coupled together by one-to-one gearing provided by the pinions 4, 5, it is of no consequence which is used for connection to the drive means or at which end the drive is applied. When the sign is easily approached the drive means may comprise a handle or hand-wheel, fitted to the shaft extension as indicated, for example at H, to enable the display matter to be changed manually. In other circumstances; when for example the sign is disposed at some height from the ground, it is convenient to use an electric notor as the drive means. In such a case it is convenient to fit the motor with a reduction gear to ensure that the sign does not change too quickly as this might make it difficult to stop the web 1 accurately at a desired position. It is obvious that means must be provided for driving the supporting rollers 2, 3 in either direction and for this purpose the electric motor employed is preferably one which is easily reversed without complicated switching, such as for example what is generally referred to as a capacitor motor where it is only necessary to make connection to either of two windings to reverse the direction of rotation, but obviously any type of motor with appropriate switching may be employed.
Whatever form of drive is used it will be seen that as the web 1 is transferred from one of the supporting rollers 2 or 3 to the other the effective length of the part of the web between the idler rollers 6, ? will initially increase until an equal amount of web is around both rollers, and then decrease as the web continues to be wound on-to the second roller. The change in the effective length of the central part of the web will be compensated for by the gravity - or spring-biased jockey roller 8 which maintains the web under tension at all times. If springs are employed, as at 9, they should be of sufficient strength to provide the required tension for the web over its whole range of movement, for example by making them as long as practicable and using a low rating spring, as with a long web the change in length of its central part may be appreciable, and the use of too highly rated springs will necessitate the use of additional power to move the web.
The sign may be enclosed in an outer casing represented by the broken line S with the display position D provided by an opening in the casing, preferably covered with a transparent panel, for example of glass (not shown) through which the matter displayed can be viewed.
The second sign, which is illustrated in Figures 3 and 4, is somewhat similar to that described with reference to Figures 1 and 2, in that it comprises a flexible web 1 carrying individual items for display and having its ends fixed to respective supporting rollers 2, 3.
In this case, however, the pinions 4, 5 fixed to the supporting roller shafts 12, 13, instead of engaging each other directly, each engages an intermediate pinion 11 connected, through reduction gearing, shown diagrammatically at 15, to the output shaft of an electric motor 14 located between the rollers 2, 3.
In addition the idler rollers 6, 7 are spaced wider apart, and two further idler rollers 16, 17 are disposed slightly below them just forwardly of the rear roller 7 as shown in Figure 4. The jockey roller 8 in this case is located at the rear of the sign, the web 1 passing beneath it between the two idler rollers ? and 17; the spring-biased jockey roller 8 is biased downwards as before by springs 9, and thereby compensates for changes in the effective length of the web 1 as it is transferred from one supporting roller to the other, and thus maintaining the web under tension throughout as in the previous embodiment.
There are occasions when a sign of the type described has to be controlled remotely, the matter displayed not being visible at the control point. When this requirement exists the web 1 may be provided with what are generally referred to as locating means, each individual sign having its own locating means as, for example at 18 (Figures 3 and 4). Many systems of position indication or location are well known, incorporating detectors of many different kinds for example proximity switches or similar electro-magnetic devices as well as opto-electronic devices. The locating means on the web 1 may be of any convenient form necessary to actuate the particular type of detector employed. For example when an opto-electronic system is used each individual sign would have its own individual mark. The signal generated by the detector (shown for example at 19) would be used to control the motor 14 driving the web 1 and cause it to stop when the selected signal matched an appropriate signal from control equipment, shown at 20, located at the remote point. This arrangement is mentioned as a known method of location which may be applied to any sign not in any way forming part of the present invention but indicates how existing practice may be associated with it.
In carrying the invention into effect when desired the sign may be front illuminated but alternatively rear illumination may be used in which case the belt may be made of transluscent material with a light source located behind it which conveniently comprise fluorescent lamps, as at L in Figure 4, the number employed being determined by the light rating of the lamps and the physical size of the sign. One application of the present invention is to provide an easy means of displaying prices of goods which change quite frequently. In such an application the web 1 can, for example, carry ten individual display items respectively showing figures from 0 to 9 one such item in the form of the Figure 7 being shown at the display position D in Figure 3. When more than a single figure is required two or more signs made as identical physical units are conveniently assembled together as a composite unit within a common casing. It will be seen that by assembling three such units, for example, any price between one penny and nine pounds ninety nine pence could be displayed. However the matter displayed can take any other required form.
When the sign is controlled by an electric motor from a remote position but with the sign visible at the control point it may be found convenient to provide the control equipment 20 with either two push buttons which cause the motor to be energised as long as they are in the closed position, one marked "Raise" and the other marked "Lower" or alternatively with a single press button for the motor together with a two position switch similarly marked.
When however the sign is controlled from an appreciable distance in conjunction with a location means of the type hereinbefore referred to it may be more convenient to provide a rotary selector switch marked with the figures 0 to 9. Operation of this switch, which may in practice select a series of electrical resistances of different value by known circuitry, causes the motor to drive the sign to the appropriate figure. It is, however, to be understood that remote control of the sign is in no way limited to the method referred to and other known systems may be used if desired. Many minor constructional modifications will be obvious to those skilled in the art and may be introduced without exceeding the scope of the present invention. For example where the overall length of the web is considerable it will be appreciated that the variation in the length of that part of the web between the supporting rollers may be greater than can be accommodated by movement of a single jockey roller within the confines of the casing of the sign, and in such a case one or more additional suitably-biased jockey rollers may be employed, the web being looped round each jockey roller in turn.

Claims

1. A roller blind sign of the kind incorporating a web of flexible material having on it a plurality of display items, and a pair of supporting rollers carrying the ends of the web characterised in that it incorporates means mechanically coupling the supporting rollers to each other for enabling them to be rotated in unison by a common reversible drive means to bring a selected one of the display items in the display position, and a movable jockey roller over which the part of the web between the supporting rollers passes, which jockey roller is biased in a direction which maintains the web under tension as it is transferred from one supporting roller to the other.

2. A roller blind sign according to Claim 1 wherein the supporting rollers are of substantially the same diameter and the coupling between them is such as to cause them to.be rotated by the drive means at an identical angular velocity.

3. A roller blind sign according to Claim 1 or 2 wherein the drive means is connected or is connectable to drive one supporting roller and that roller is connected to the other by interengaging pinions, or by a chain and sprockets, or by a timing belt and cooperating pulleys.

4. A roller blind sign according to Claim 1 or 2 wherein the drive means is connected or is connectable to an intermediate rotatable member drivingly coupled to both supporting rollers.

5. A roller blind sign according to any preceding Claim wherein the shaft of at least one of the supporting rollers, or of a said intermediate rotatable member where provided, is provided with an extension drivingly engageable with a handle or hand-wheel for enabling the position of the web to be changed manually.

6. A roller blind sign according to any one of Claims 1 to 4 wherein the drive means comprises a reversible electric motor connected to one of the drums, or to a said intermediate rotatable member where provided, through a reduction gear system.

7. A roller blind sign according to Claim 6 in which the operation of the electric motor is controllable by control means located at a control position remote from the main body of the sign, and which incorporates means for generating position indicator signals indicative of the position of the web, and display means at said control position responsive to said signals for indicating which of the display items is in the display position.

8. A roller blind sign according to Claim ? wherein each display item has associated with it on the web or on means movable therewith a position indicator corresponding to that item, and the sign incorporates a detector located adjacent the path of the position indicators on movement of the web and arranged to generate a said position indicator signal appropriate to a respective display item when that item approaches or reaches the display position.

9. A roller blind sign according to Claim 7 or 8 incorporating means responsive to said position indicator signals for automatically stopping the drive motor when a selected display item reaches the display position.

10. A roller blind sign according to any preceding Claim incorporating one or more additional webs each associated with respective supporting rollers and jockey roller, and mounted within a common casing.