GB2327667A

GB2327667A - Card transport device

Info

Publication number: GB2327667A
Application number: GB9815840A
Authority: GB
Inventors: Graham Gutsell; Clive Ayling; Steven Doyle
Original assignee: Thorn Secure Science Ltd
Current assignee: Thorn Secure Science Ltd
Priority date: 1997-07-25
Filing date: 1998-07-21
Publication date: 1999-02-03
Anticipated expiration: 2018-07-21
Also published as: GB2327667B; GB9715604D0; TW448123B; JPH11134443A; GB9815840D0; KR19990014139A

Abstract

A card or ticket transport apparatus comprises a plurality of pinch drive means (1,2, 3), consisting of a drive roller (4, 5, 6) facing and resiliently biased towards a follower roller (7, 8, 9), to feed a card or ticket along a transport path (11) therebetween. The follower rollers (7, 8, 9) are carried by a carriage (12) which is pivotably moveable, in response to the presence of a card or ticket, to vary the spacing between the cooperating rotatable members. This arrangement reduces jitter during card transport in magnetic, optical, or electronic reader/encoder systems.

Description

A CARD OR TICKET TRANSPORT APPARATUS This invention relates to a card or ticket transport apparatus, comprising a plurality of pinch drive means, each having a rotatable drive member facing and being biased relative to a corresponding rotatable follower member which co-operates with the drive member, for feeding a card or ticket along a transport path. This invention also relates to card or ticket reader and/or encoder systems incorporating such apparatus.

A known apparatus of this general type is disclosed in US 4,886,957, although many similar systems have been described from time to time in the prior art. Another type of document feeder is disclosed in GB 2289885. A problem with both of these prior art feeder systems is that large frictional forces must be overcome when the edge of a document encounters the pinch drive means. This causes unwanted variations in speed of the document (known as jitter) as it passes along the transport path in use. This can make reading data on the card more difficult, and can damage thin documents.

According to one aspect of the present invention there is provided a card or ticket transport apparatus as specified in the daims.

This arrangement causes a given pinch drive means to be free to open in a relatively compliant state when a card or ticket approaches it, due to the see-saw action of the pivotably moveable carriage, thereby reducing unwanted speed variations during card or ticket transport, and making the reading of data on the card or ticket easier.

It is an object of the present invention to provide an improved card or ticket transport apparatus suitable for use in magnetic, optical, or electronic reader and/or encoder systems, and particularly, though not exclusively, for systems in which card or ticket transport is bi-directional.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawing, in which: Figure 1 shows a front elevation of an apparatus according to the invention at various times as a card or ticket passes along the transport path.

In Figure la, a card or ticket transport apparatus is shown which comprises a plurality of pinch drive means (1, 2, 3), each having a rotatable drive member (4, 5, 6) which faces and is biased relative to a corresponding rotatable follower member (7, 8, 9) which co-operates with the drive member for feeding a card or ticket (10) along a transport path (11). Rotatable members (7, 8, 9) from two or more of the plurality of pinch drive means on a given side of the transport path are carried by a carriage (12) which is pivotably moveable. In the present example, the rotatable drive members are rollers or wheels, which are mounted on a frame (14) in a straight line arrangement in which they all share a common plane of rotation parallel to the plane of the paper. The carriage (12) carrying the corresponding follower rollers is biased towards the drive members (in the present example resiliently) by the action of a resilient member, such as for example a spring (15), attached to the frame (14) and mounted adjacent the central pinch drive means. This biases the carriage (and hence the follower rollers) towards the drive rollers mounted on the frame in use. This arrangement also enables the carriage (12) to pivot about one end of the spring in the plane of rotation of the rotatable members - i.e. parallel to the plane of the paper. This movement resembles that of a see-saw as will be described in detail later. In the present example, optional end stops (17, 18) are provided, to ensure that there is a space between the drive and follower rotatable members in the absence of a card or ticket in the transport path. The end stops may be adjustable so that different spacings can be set, in order that the apparatus may be adjusted for use with various thicknesses of card or ticket.

Although in the present example the central set of rotatable members comprises drive and follower wheels or rollers, this central driven member can be replaced by an idler member (such as a wheel or a roller) if the distance between the other two pinch drive means is less than the length of the ticket or card being transported.

Figure 1b shows what happens when a card or ticket (10) is introduced to the apparatus from the right hand side, moving towards the left hand side of the Figure. The card enters the right hand pinch drive means (comprising rotatable nip rollers 6 and 9). The resilient member (15) is compressed by lever action of the carriage (12), which pivots on the left hand end stop (17). If this end stop were not present, the carriage would pivot about drive member 4.

Figure ic shows the situation for the same apparatus a short time later, by which time the card or ticket has been transported to the left by the right hand pinch drive means, and is about to enter the central pinch (in the present example comprising driven roller 5 and follower roller 8). The presence of the card or ticket causes the resilient member 15 to be compressed to its greatest extent. As a result the carriage is now dear of both end stops (17, 18). Card reading and/or encoding may now proceed by means of the magnetic read and/or write head (19) which is located on the carriage adjacent the axis of rotation of follower roller 8 and which co-operates with a magnetic strip on the card or ticket (not shown). As an alternative this head may be carried by the frame (14) if desired. A plurality of read and/or encode heads may be provided.

In Figure ld, the card or ticket has been transported to the left by the right hand pinch drive means and/or the central pinch drive means, and is about to leave the right hand pinch drive means. Since there is no net imbalance in forces at this time, the right hand pinch does not dose, so that the card or ticket transport speed does not jitter as in a conventional transport mechanism. In addition, the left hand pinch drive means (comprising driven roller 4 and follower roller 7) is now free to open to substantially the correct extent to receive the card or ticket.

Figure le shows the situation a short time later, by which time the card or ticket has been transported to the left by the centre pinch drive means, and is about to enter the left hand pinch drive means. As the card or ticket enters the left hand pinch drive means, it will experience very little speed jitter as the pinch is already open at approximately the correct spacing to receive the card or ticket, and the restoring force of the resilient member (in the present case the spring 15) acts substantially through the rotatable members comprising the central pinch drive means, thus minimising the resistance to change in the spacing of the other rotating members, and thus providing a mechanism having a low stiffness (i.e. a high compliance).

The cause of unwanted speed variation when entering a pinch drive means is due to the requirement to overcome biasing forces when opening the gap between the rollers to the correct value. In general, these speed variations will occur if the gap is smaller than the card or ticket thickness. It is always difficult to ensure correct gap size because of manufacturing tolerances.

However, in the present design, the resistance to opening the gap of the pinch drive means consists mainly of inertial forces, with very little contribution from the restoring force of the spring. Even when the first pinch drive means is encountered, the lever action of the carriage pivoting about its opposite end provides a mechanical advantage for compressing the resilient member 15.

In Figure If, the card or ticket has been transported to the left by the left hand pinch drive means comprising driven roller 4 and follower roller 7, such that the card or ticket has left the central pinch drive means. The resilient member 15 is therefore under less compressive stress, and relaxes upwards such that the carriage rises and pivots to engage with the right hand end stop 18. As the card or ticket is no longer adjacent the read and/or write head, the reading and/or encoding of data must have stopped by this time.

Although in the above embodiment the rotatable drive members are rigidly mounted on the frame (14), as an alternative they may be resiliently coupled to the frame.

In the above embodiment the rotatable members carried by the carriage (12) are idler or follower rotatable members. Such an arrangement is easy to manufacture, as the drive means for the driven rotatable members does not have to cope with the moveable carriage (12). However, if desired, one or more rotatable drive members may be mounted on the carriage (12) as an alternative.

Lastly, the accompanying claims and abstract are incorporated herein by reference.

Claims

1. A card or ticket transport apparatus, comprising a plurality of pinch drive means (1, 2, 3), each having a rotatable drive member (4, 5, 6) facing and being biased relative to a corresponding rotatable follower member (7, 8, 9) which co-operates with the drive member, for feeding a card or ticket along a transport path (11), characterized in that the rotatable members (4, 7,6,9) comprising two or more of the pinch drive means (1, 3) are spaced from one another to provide a gap therebetween corresponding to the thickness of the card or ticket (10) or a fraction thereof, a rotatable member (7, 9), from each of two or more of the said plurality of pinch drive means, on a given side of the transport path, being carried by a carriage (12) which is pivotably moveable in response to the presence of a card or ticket, to permit variation of the said gap, for minimising unwanted speed variations of the card or ticket in use.

2. A card or ticket transport apparatus as claimed in claim 1 in which the carriage is pivotably moveable about at least two pivots (17, 18) spaced along the transport path.

3. A card or ticket transport apparatus as daimed in any preceding claim in which the rotatable members (7, 8, 9) being carried by the carriage (12) are biased resiliently relative to the corresponding rotatable members not being carried by the carriage.

4. A card or ticket transport apparatus as daimed in any preceding claim in which the carriage is biased resiliently relative to the corresponding rotatable members (4, 5, 6) not being carried by the carriage.

5. A card or ticket transport apparatus as claimed in any preceding claim in which the rotatable members (7, 8, 9) being carried by the carriage (12) are follower members.

6. A card or ticket transport apparatus as claimed in any preceding daim in which the pivot (s) is (are) adjacent a rotatable member (7, 8, 9) on the transport path (11).

7. A card or ticket transport apparatus as claimed in any preceding daim including a read and/or write head (19) adjacent said transport path.

8. A card or ticket transport apparatus as claimed in claim 7 in which said read and/or write head is responsive to magnetic signals.

9. A document reader and/or encoder system including a card or ticket transport apparatus as claimed in any preceding claim.