JPH0682447B2 - Recording / reproducing method of magnetic card reader - Google Patents

Description

The present invention relates to a recording / reproducing system of a magnetic card reader.

[Conventional technology]

Conventionally, recording / reproducing of this kind of magnetic card reader consists of a method using a read / write magnetic head with the same write track width and read track width, and two windings with a read track width narrower than the write track width. There is a recording / reproducing system using a so-called combination head.

Checking the writing status of the magnetic card is an effective means for monitoring the life of the magnetic head of the magnetic card reader and the contact status between the magnetic head and the magnetic card recording unit.
Generally, it is executed by comparison (verification) of read data after writing.

FIG. 2 is a diagram showing the relationship between the write track and the read track when the write track width and the read track width are the same in the recording / reproducing system using the conventional read / write magnetic head, and 10 is a magnetic card. , 11
Is a write track, 12 is a read track at the time of verification, and 13 is a read track. Where the reference numerals are shown side by side, the two tracks have the same width and overlap. In this recording / reproducing system, the write track 11 and the read track 13 have the same width, and the write track width is read over the entire width, so that the magnetic head and the recording portion of the magnetic card are misaligned between the card reader devices. If a part of the writing width direction is not recorded normally, that is, if the read track is indicated by 13 'instead of 13, or if the magnetic head and the magnetic recording part are not in close contact, the output is It is output from the magnetic head as noise because the magnetic recording is reduced or magnetic recording remains before writing.
Therefore, when a read / write magnetic head is used, the writing state is highly reliable, but the above-mentioned output drop is caused by the difference in the positions of the mechanical magnetic head and the magnetic card recording unit between the magnetic card reader devices. Since this causes noise and causes poor compatibility between devices, it has the drawback of requiring high mechanical accuracy.

FIG. 3 is a diagram showing the relationship between the tracks on the magnetic card 20 in the recording / reproducing system (described above) using the combination head developed to improve the compatibility between the devices. In this recording / reproducing system, the read track 22 and the read track 23 at the time of verification
Is located at the center of the write track 21, and even if the positions of the magnetic head and the magnetic card recording unit are slightly deviated, the operation is performed for the time being, so that it is excellent in terms of compatibility.

[Problems to be solved by the invention]

However, in the recording / reproducing method using the combination head with the narrowed read track width, the writing state is checked only in a part of the recording portion of the magnetic card in which the writing is performed. As compared with the read / write head, the performance is remarkably deteriorated.

As a method for solving the above drawbacks, there is a method of providing a plurality of magnetic heads with a redundant function, but there is a drawback that the cost increases.

Therefore, it is an object of the present invention to increase the compatibility between magnetic card reader devices without impairing the reliability of the writing status check.

[Means for solving problems]

According to the present invention, in the magnetic card reader having the writing function, the reading of the magnetic card data for the read data comparison after writing the magnetic card is performed with the same track width as the magnetic card writing track width. The read / write method of the magnetic card reader is characterized in that the read is performed with a track width narrower than the write width of the magnetic card.

〔Example〕

FIG. 1 is a diagram showing the positions of the writing and reading tracks in the recording / reproducing system of the magnetic card reader according to the embodiment of the present invention, and the verification is performed on the magnetic card 30 with the same track width as the writing track 31. At this time, the track 32 is read to check the output signal, and the normal reading is performed by the read track 33, so that the device compatibility between the card readers can be easily ensured.

FIG. 4 is a diagram showing the configuration of a magnetic head drive circuit for realizing the mutual relationship of the three tracks in the embodiment of FIG. 1, and the writing winding 42 of the magnetic head 41 is used for reading during writing and verifying. The write current is controlled by the write drive circuit 43, and the reproduction output at the time of reading is input to the first amplifier for verification 44.

Normal reading is performed by the read-only winding 45 having a track width narrower than the track width of the write winding 42 of the magnetic head 41, and the reproduction output is the read-only second amplifier.
Entered in 46.

The gate circuit 47 selects the output from the first amplifier 44 and the second amplifier 46 by reading at the time of verification and reading of normal magnetic card data. Naturally, the gain of the first amplifier 44 is made lower than the gain of the second amplifier 46 to check the writing state with higher reliability. The gate circuit 47 and the switch 48 form a pair to form the switch circuit 19. The output of this switch circuit is demodulated by the double-width circuit 50 to generate the device output.

Generally, the deterioration of the written state often occurs from the direction perpendicular to the written track. That is, the write track width advances in the direction of decreasing. However, since a write error may occur only in the central part of the track, the write winding 42 and the read-only winding 45 are used for verifying in order to check the write state with higher reliability. Doing is also an effective means.

FIG. 5 shows that the output signals from the write winding 42 and the read-only winding 45 are input to the first amplifier 44 and the second amplifier 46, respectively, and both output signals are first demodulated. The circuit 51 and the second demodulation circuit 52 demodulate into binary data, and the arithmetic circuit 53 executes a comparison check with the write data.

As described above, according to the present invention, it is possible to always provide a highly reliable magnetic card reader capable of checking the writing state over the entire track width and increasing the compatibility between the card reader devices. .

[Brief description of drawings]

FIG. 1 is a diagram showing the positions of write tracks and read tracks in the recording / reproducing system of the magnetic card reader of the present invention, and FIGS. 2 and 3 are diagrams showing the positions of write tracks and read tracks in the conventional system. 4 and 5 are block diagrams of the magnetic head drive circuit according to the method of the present invention. Symbol description: 10 is a magnetic card, 21 is a writing track, 22
Is a read track at the time of verification, 23 is a read track, 31 is a write track, 32 is a read track at the time of verify, 33 is a read track, 41 is a magnetic head, 42
Is a write winding, 43 is a write drive circuit, 44 is a first amplifier, 45 is a read-only winding, 46 is a second amplifier, 47 is a gate circuit, 49 is a switch circuit, 50 is a demodulation circuit, and 51 is a first 1 is a demodulation circuit, 52 is a second demodulation circuit, and 53 is an arithmetic circuit.

Claims (1)

[Claims] 1. In a magnetic card reader having a writing function, reading of magnetic card data for comparison of read data after writing to the magnetic card is performed with the same track width as the magnetic card writing track width. A read / write method for a magnetic card reader, which is characterized in that reading is performed with a track width narrower than the magnetic card write track width.