GB2156121A

GB2156121A - Magnetic card reading equipment

Info

Publication number: GB2156121A
Application number: GB08506940A
Authority: GB
Inventors: E R Jervis
Original assignee: GEC TRAFFIC AUTOMATION
Current assignee: GEC TRAFFIC AUTOMATION
Priority date: 1984-03-23
Filing date: 1985-03-18
Publication date: 1985-10-02
Also published as: GB2156121B; GB8506940D0; GB8407660D0

Abstract

In magnetic card reading equipment, the card (20) is moved along a transport path (13, 17) by a drive wheel (30) which presses the card against a magnetic head (40). A resilient frusto-conical bevelled portion of the drive wheel imposes a lateral bias on the card to maintain it securely against a bearing surface (12) to one side of the path. The card has a centrally disposed magnetic strip (21), the drive wheel and magnetic head being accordingly spaced from the bearing surface (12) by half the width of the card, and sufficient lateral bias is provided by tilting the rotational axis (32) of the drive wheel to effectively increase the bevel. A wheel having a bevel ( alpha ) of 1 degree and tilted ( beta ) by 2 degrees has been found to provide a more effective bias than a wheel having a bevel of 3 degrees. <IMAGE>

Description

SPECIFICATION Magnetic card reading equipment This invention relates to card reading and transport means of magnetic card reading equipment.

In particular this invention relates to a card reading and transport means of magnetic card reading equipment comprising a guideway for the pasage of such a card, a bearing surface forming one side of the guideway and defining the transport path of the card, a drive wheel arranged to bear upon the card to drive the card along said transport path, and a magnetic head located opposite the drive wheel to be slidingly engaged by the card which is pressed thereagainst and moved thereover by the drive wheel, the drive wheel having its rotational axis in a plane perpendicular to the plane of the transport path, and the drive wheel being of bevelled frusto-conical form with increasing radius towards the side of the guidway which is formed by said bearing surface, at least the bevelled portion of the drive wheel being resilient, whereby the drive wheel imposes a lateral bias on the card to thrust the card against said bearing surface while driving it along said transport path.

Card reading and transport means as described above are known from U.K. Patent Application No. 2,096,808A wherein the drive wheel and the magnetic head are shown close to said bearing surface so that the drive wheel presses a card against the magnetic head along a strip of the card close to one longitudinal edge of the card, and the rotational axis of the drive wheel is parallel to the plane of the transport path.

According to the invention there is provided card reading and transport means as described in the penultimate paragraph, characterised in that it is for use with such a card having magnetic data on a lengthwise extending strip which is centrally disposed with respect to the width of the card, in that the drive wheel and the magnetic head are laterally spaced from said bearing surface by half the width of such a card whereby the drive wheel presses the central strip of the card against the magnetic head, and in that the rotational axis of the drive wheel is tilted with respect to the plane of the transport path, the angle of tilt being such as to effectively increase the frusto-conical bevel of the drive wheel in order to provide sufficient said lateral bias on the card.

A card having magnetic data on a lengthwise extending strip which is centrally disposed with respect to the width of the card can be processed by a correspondingly centrally disposed magnetic head according to a first predetermined process with one end of the card being the front end which first reaches the magnetic head upon insertion of the card into the equipment toward the head.

By turning the card through 1 80 degrees about an axis perpendicular to its plane so that the other end of the card becomes the front end, the magnetic data on the same central strip can be processed by the same magnetic head according to a second, different, predetermined process. One such application for such a magnetic card having magnetic data on a centrally disposed strip is with vehicle parking meters using such a magnetic card as a token, wherein the first process with the card inserted one way decrements the value of the card and the second process with the card inserted the other way displays the value of the card without decrementing it.

The magnitude of the lateral bias provided by the drive wheel in card reading and transport means as described in the second paragraph of this specification is dependent on the orientation of the rotational axis of the drive wheel, the material of the bevelled frustoconical portion of the drive wheel and the amount of that bevel. In an arrangement as disclosed in the above-mentioned U.K. Application No. 2,096,808A, that is to say with the rotational axis of the drive wheel parallel to the plane of the transport path, the material of at least the bevelled frusto-conical portion of the drive wheel being polyurethane and the drive wheel being close to the bearing surface, it has been found that a slight angle of bevel of approximately 1 degree results in sufficient lateral bias being provided by the drive wheel to maintain the card securely against the bearing surface of the guideway.

If this arrangement is adapted for use with cards having magnetic data on a centrally disposed strip, as described in the previous paragraph, by merely moving the drive wheel and magnetic head laterally away from the guideway bearing surface to the position of the central strip then the lateral bias provided by the drive wheel becomes insufficient.Different drive wheels having increased angles of bevel have been tried, but surprisingly it has been found that this is not nearly so effective in providing the required increase in lateral bias to maintain the card securely against the bearing surface of the guideway as using a drive wheel with the same slight angle of bevel, that is to say approximately 1 degree, but tilting the rotational axis of the drive wheel with respect to the plane of the transport path by a small angle of the same order as the angle of bevel of the wheel, that is to say an angle of tilt of approximately 2 degrees, such that the angle of bevel of the drive wheel is instead effectively increased.

The above-mentioned U.K. Application No.

2,096,808A discloses springs projecting into the guideway from the side away from the bearing surface to align the card in the guideway when it is not in contact with the drive wheel and also to apply additional lateral bias to the card when it is in contact with the drive wheel. Such springs may equally be used in arrangements according to the invention.

An embodiment according to the invention of card reading and transport means of magnetic card reading equipment will now be described with reference to the accompanying drawings, in which, Figure 1 shows a front section view of the guideway, drive wheel and magnetic head of the reading and transport means, Figure 2 shows a side section view of the parts shown in Fig. 1 together with a magnetic card passing through an entrance slot of the guideway, and Figure 3 shows a top view of the guideway with its top removed and a magnetic card passing under the drive wheel, and illustrates the deformation of the part of the drive wheel which bears on the card.

Referring now to the drawings, card reading and transport means of magnetic card reading equipment includes a guideway having top and bottom plates 10, 11. A strip 1 2 of material having a low coefficient of friction provides a bearing surface forming one side of the guideway and defines the transport path 1 3 of a magnetic card 20 inserted through a front slot 14 (Fig. 2). A drive wheel 30 is arranged to extend through an opening 1 5 in the plate 10 and to bear upon the card 20 to drive the card 14 along the transport path 1 3 when driven by a motor 31.A magnetic head 40 is located to extend through an opening 1 6 in the plate 11 opposite the drive wheel 30 and to be slidingly engaged by the card 20 which is pressed thereagainst and moved thereover by the drive wheel 30. The top of the magnetic head 40 and the bottom of the drive wheel 30 meet in the plane of the transport path 1 3 (shown by the dashed line 17 in Fig. 1).

The card 20 has magnetic data on a lengthwise extending strip 21 of the card 20 which is centrally disposed with respect to the width of the card (shown by the dotted lines in Fig.

3) and the drive wheel 30 and the magnetic head 40 are laterally spaced from the bearing surface of the strip 1 2 by half the width of the card 20 so that the drive wheel 30 presses the central strip 21 of the card against the magnetic head 40.

The rotational axis 32 of the drive wheel 30 is in a plane perpendicular to the plane 1 7 of the transport path. The drive wheel 30 is formed of resilient deformable materials, for example polyurethane, and is of bevelled frusto-conical form with increasing radius towards the side of the guideway formed by the strip 12. When in contact with the card 20, the part of the drive wheel which bears on the card is deformed (as shown in Fig. 3) so that the drive wheel 30 imposes a lateral bias on the card 20 to thrust the card against the bearing surface of the strip 1 2 while driving it along transport path 13. Polyurethane may go hard at very low temperatures, and the resilience of the bevelled portion of the wheel in these conditions is safeguarded by providing a recess in the larger face of the wheel near the rim.

Two springs 18 project into the guideway from the side away from the strip 1 2 to align the card 20 in the guideway when it is not in contact with the drive wheel 30 and also to apply additional lateral bias to the card 20 when it is in contact with the drive wheel 30.

The actual angle of bevel of the drive wheel 30, that it is say the angle a (Fig. 1) between the outer surface of the wheel and its rotational axis 32 may suitably be a slight angle of approximately 1 degree. The rotational axis 32 of the drive wheel 30 is tilted with respect of the plane 1 7 of the transport path, the angle of tilt ss (Fig. 1) being such as to effectively increase the frusto-conical bevel of the drive wheel 30 in order to provide sufficient lateral bias on the card 20 to maintain it securely against the bearing surface of the strip 1 2. The angle of tilt ss of the rotational axis 32 of the wheel 30 may suitably be a small angle of the same order as the actual angle a of bevel of the wheel 30, that is to say approximately 2 degrees. The wheel thus has an effective angle of bevel y (3 degrees) (Fig. 1) which is the sum of the angles a and ss

Claims

1. Card reading and transport means of magnetic card reading equipment comprising a guideway for the passage of such a card, a bearing surface forming one side of the guideway and defining the transport path of the card, a drive wheel arranged to bear upon the card to drive the card along said transport path, and a magnetic head located opposite the drive wheel to be slidingly engaged by the card which is pressed thereagainst and moved thereover by the drive wheel, the drive wheel having its rotational axis in a plane perpendicular to the plane of the transport path, and the drive wheel being of bevelled frusto-conical form with increasing radius towards that side of the guideway which is formed by said bearing surface, at least the bevelled portion of the drive wheel being resilient, whereby the drive wheel imposes a lateral bias on the card to thrust the card against said bearing surface while driving it along said transport path, characterised in that the card reading and transport means is for use with such a card having magnetic data on a lengthwise extending strip which is centrally disposed with respect to the width of the card, in that the drive wheel and the magnetic head are laterally spaced from said bearing surface by half the width of such a card whereby the drive wheel presses the central strip of the card against the magnetic head, and in that the rotational axis of the drive wheel is tilted with respect to the plane of the transport path, the angle of tilt being such as to effec tively increase the frusto-conical bevel of the drive wheel in order to provide sufficient said lateral bias on the card.

2. Card reading and transport means sub stantially as herein described with refernce to I the accompanying drawing.