JPH0780582B2 - Card carrier - Google Patents

Description

TECHNICAL FIELD The present invention relates to a card carrying device in a card reader / writer.

[Prior Art] In a conventional general card reader / writer, a roller type card conveying device is used. In this device, a drive roller and a driven roller are arranged inside the card entrance / exit, a card is sandwiched by both rollers to generate a frictional force between the card and the drive roller, and in that state, the motor rotates the drive roller. By doing so, the card is conveyed.

A magnetic head in the case of a magnetic card and a contactor in the case of an IC card come into contact with a card conveyed by such a device. Therefore, the transporting device is given a transporting ability in consideration of the contact pressures thereof.

[Problems to be Solved by the Invention] However, when the surface of the card is dirty, the drive roller may slip and a sufficient conveying force may not be obtained. In that case, once a slip occurs, the frictional force between the drive roller and the card is extremely reduced, and it becomes impossible to convey the card to a predetermined position inside the device. May become inaccessible.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a card transport device that can transport a card to a target position even if some slip occurs.

[Means for Solving the Problems] The card carrier of the present invention is configured as follows in order to solve the above problems.

The first card transport device is a card transport device that transports a card inserted into a card insertion / exit slot between a drive roller and a driven roller and rotates the drive roller by a motor to transport the card inside the device. When a card does not reach a predetermined position inside the device even after a lapse of a predetermined time from the start, means for judging the slip, and when the means judges the slip, the motor is set so that the drive roller and the drive card are relatively stationary. Motor control means for controlling the chopper so as to rotate intermittently.

Further, the second card carrying device is characterized in that it is provided with a device for making a slip judgment by detecting a change in rotation of the motor, instead of the slip judging device of the first card carrying device.

[Operation] In the roller type transporting device, when the drive roller slips due to dirt on the surface of the card, the card does not reach the predetermined position inside the device naturally.
In the first device, the slip determination means determines the slip of the drive roller when this time is exceeded. When the slip determination is made, the motor control means switches from the continuous rotation control up to now to the chopper control. That is, the voltage is supplied to the motor in a pulsed manner to intermittently drive the motor.

Here, when the drive roller is slipping with respect to the card, dynamic friction acts between the drive roller and the card surface, but once the chopper control is performed, the drive roller and the card are stopped for a moment. When the state is achieved,
A frictional force, which is much larger than the dynamic friction and is close to static friction, acts between the drive roller and the card.

Therefore, by intermittently rotating the drive roller under chopper control, the slip ratio is suppressed and the carrying force is increased. Then, in the case of a light slip state, the card can be reliably conveyed.

Further, in the case of the second device, slip determination is performed based on the change in rotation of the motor. Here, the rotation change that serves as a criterion for determination will be described. First, when the card is not sandwiched between the driving roller and the driven roller, the driving roller idles in the unloaded state. The rotation speed of the motor at that time is the idling speed No.

If the card is sandwiched between the driving roller and the driven roller and the driving roller is slipping naturally with respect to the card, the dynamic frictional force acts, so the motor rotates at a speed Ns close to idling but slightly slower than idling. . Further, when the card is intentionally held so as not to be conveyed, even in the same slip state, a slip rotation state with a large load is brought about, so that the rotation of the motor further slows down. If the speed at this time is Nk, there is a relationship of Nk <Ns <No.

Therefore, by detecting this change in the rotation speed, the above three states, idling, natural slip, and intentional slip can be distinguished. Then, when the rotation is equivalent to natural slip, the slip determination means determines that it is slip. Then, at that time, the motor control device chopper-controls the motor. After that, the card is conveyed to the target position by the same principle as in the case of the first device. If the above determination is intentional slip, for example, a card ejection operation is performed.

[Embodiment] An embodiment in which the present invention is applied to an IC card reader / writer will be described below with reference to the drawings.

FIG. 1 shows a schematic structure of a card carrier of the embodiment. 1
Is a card entrance / exit, and a driving roller 2 and a driven roller 3 for conveying the card K are provided in a pair in the vicinity of the inside of the card. The driven roller 3 is biased by a leaf spring 4 so that the inserted card K can be nipped with the drive roller 2 with a predetermined contact pressure.

A head 6 having a contact 5 is provided on the back side of the drive roller 2 so as to be slidable along an inclined guide 7. Then, when the card K is conveyed inside the apparatus, the head 6 is pushed by it and moves to the back side, and the contact 5 on the lower surface of the head 6 comes into contact with the contact on the upper surface of the card K in accordance with the operation, It is accessible in the state.

The drive roller 2 is connected to the DC motor 10 via a speed reduction mechanism, and by switching the rotation direction of the motor 10, it is possible to carry in the carry-in direction and carry in the discharge direction. A front limit switch (hereinafter abbreviated as front LS) 11 for detecting the insertion of the card K is provided near the card entrance / exit 1, and the card K is located at a proper accessible position at the back of the device. A rear limit switch (hereinafter abbreviated as rear LS) 12 for detecting that the sheet has been transported to is provided.

20 is a control device including a microcomputer. This control device 20 includes a front LS11, a rear LS12, and a motor.
A drive signal is supplied to the motor drive circuit 14 based on the signal input from the rotation detector 13 that detects the rotation of 10.

This control device 20 is a slip judging means equipped with a timer.
The slip determining means 20A includes a predetermined time (time required for the card K to be transported to the access position in the normal transport state) after the front LS11 is turned on.
Even after a while, when the card detection signal "The card came to the access position" is not input from the rear LS12,
"Drive roller 2 is slipping on card K"
It has a function to judge.

The slip determination means 20A intentionally (artificially) presses the card K depending on the signal level from the rotation detector 13 of the motor 10 whether the drive roller 2 is idling or naturally slipping. It also has a function of determining whether the drive roller 2 is slipping in an unnatural state. As a criterion for discrimination, as shown in FIG. 7, A, B
The following two values are given: when the motor rotation speed when a constant voltage is applied is higher than A, idling, when it is A or less and B or more, natural slip, when it is less than B, intentional slip, It is supposed to be judged.

Further, the control device 20 has a "normal control mode" in which the motor applied voltage is continuously kept constant in order to continuously rotate the motor 10, and a "chopper" in which the motor applied voltage is pulsed in order to intermittently rotate the motor 10. Control mode 20 which selectively outputs "motor control signal" by selectively selecting "control mode"
Have B.

As the chopper control mode in this case, there are prepared three modes in which the pulse period and the pulse width are changed. Differences between the three modes are shown in FIGS.
In the figure, the solid line shows the motor applied voltage, and the chain double-dashed line shows the motor rotation speed. As shown in FIG. 4, the chopper mode 1 is a mode in which a pulse voltage with a short width is applied at a somewhat long cycle. The chopper mode 2 is the chopper mode 1
This mode has a slightly smaller cycle and the same pulse width. The chopper mode 3 is a mode in which a single pulse voltage having a large width is applied.

Next, the operation of the control device 20 will be described. Two cases will be described as operation examples. The first example is an example in which slip determination is performed only by checking the transport time, as shown in the flowchart of FIG. Therefore, when performing this control, the rotation detector 13 may be omitted. Also, the second
As shown in the flowchart of FIG. 3, the example of is an example in which it is determined whether the slip is a natural slip or a deliberate slip based on the change in the rotation of the motor in addition to the check of the transport time.

First, the first example will be described with reference to FIGS. 1 and 2.

When the card K is inserted from the card entrance / exit 1, the front
The LS11 is turned on, the control device 20 starts operating, and the processing of FIG. 2 starts. At the start stage, initialization is performed, and at the same time, the motor 10 continuously rotates in the carry-in direction to carry the card K inside the apparatus and the timer is activated. When the rear LS12 is turned on within the predetermined time T, the motor 10 is stopped, the card catch flag is set, and the process proceeds to the next data reading process (steps 101, 10).
2, 103, 104).

If the rear LS12 does not turn on even after the specified time has passed,
It is determined that slip has occurred, and the determination in step 102 is YES. Then, the motor 10 is once stopped (step 10
5) After that, the motor is controlled in the chopper mode 1 (step 106). This control is performed for a predetermined time, after which the state of the rear LS12 is checked (step 107), and O
In the N state, the motor is stopped (step 103).

If the rear LS12 is not in the ON state, go to the next step 10
At 8, it is determined whether the card K has been removed. If not, the motor control is performed in the next chopper mode 2 (step 109). If it is extracted, the motor 10 is stopped (step 118), and the process ends.

If the card K is not conveyed to the target position even in the chopper mode 2, the motor is controlled in the chopper mode 3 (step 112). After the chopper control in each mode, the state is checked from the rear LS12 each time, and if it is ON, the process proceeds to step 103, the motor 10 is stopped, and the process proceeds to the next process. If the card K is removed in the middle of the process, the motor 10 stops and ends (steps 111, 1).
14, 118).

Then, if the rear LS12 does not turn on even though the motor control was finally performed in the chopper mode 3, if the rear LS12 does not turn on again,
Returning to step 105, chopper modes 1, 2, and 3 are repeated. Then, repeat this three times (steps 115, 1
If the card is not conveyed even after 16), the card K is discharged (step 117), the motor 10 is stopped (step 118), and the process ends.

When such control is performed, escape from the tip is performed as follows.

First, in normal conveyance, the motor is continuously rotated to convey the card K into the apparatus. Therefore, it is assumed that the slip occurs due to dirt on the surface of the card. Then, the frictional force between the drive roller 2 and the card K drops extremely. This is because the friction coefficient becomes the dynamic friction coefficient.

When the chopper control is performed in this state, when the rotation speed of the motor becomes low and the rotation speed of the drive roller 2 decreases, the drive roller 2 and the card K are in a relatively stationary relationship for a moment. . Then, between the drive roller 2 and the card K, a static friction much larger than a dynamic friction acts. Therefore, the drive roller 2 is intermittently rotated by the chopper control, so that the slip ratio is suppressed and the carrying force is increased. Then, in the case of a light slip state, the card K is reliably conveyed to the target position.

In this case, when it is not transported in chopper mode 1,
Chopper mode 2 and chopper mode 3 are sequentially executed,
Since the average voltage gradually increases, the card is conveyed in a mode suitable for the slip situation at that time. Further, since the execution of each mode is repeated up to three times, the certainty of conveyance is increased.

Next, an example of the second control will be described with reference to the flowchart of FIG.

The start of this processing is the same as in the case of the first example. At the start stage, initialization is performed, and at the same time, the motor 10 continuously rotates in the carry-in direction to carry the card K inside the apparatus and the timer is activated. And rear
While monitoring the state of the LS12 (step 201), a change in the rotation of the motor is detected to determine whether it is a natural slip or a deliberate slip (step 202). If it is determined that the intentional slip has occurred, the card ejection operation is immediately executed (step 219), and the motor 10 is stopped (step 2).
20).

If the intentional slip does not occur, when the rear LS12 is turned on within the predetermined time T, the card K has reached the predetermined position, the motor 10 is stopped, the card catch flag is set, and the next data reading is performed. The process moves to (steps 201, 203, 204, 205).

If the rear LS12 does not turn on even after the predetermined time T has passed, it is determined that a natural slip has occurred (step 203).
Then, the motor 10 is once stopped (step 206), and then the motor is controlled in the chopper mode 1 (step 207). Subsequent procedures are substantially the same as in the case of the first control example described above. The difference is that chopper mode 1, 2, 3
After that, it is judged again whether the natural slip is a deliberate slip (step 216). If it is a natural slip, the procedure returns to step 206 again, and the chopper mode is sequentially repeated. Is performed (step 219).

In the case of this control, even if conveyance is impossible due to the same slip, in case of intentional slip, it is immediately discharged without chopper control, and in case of natural slip, it is tried to convey to the target position as much as possible by chopper control. To do. Therefore, useless processing is omitted.

[Effects of the Invention] As described above, according to the card carrier of the present invention, when the drive roller slips, the chopper control is performed such that the motor is intermittently rotated so that the drive roller and the card are relatively stationary. Therefore, in the case of some slip, the card can be reliably conveyed to a predetermined position in the device. Therefore,
It is possible to realize a highly reliable device.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of a card carrier according to the present invention, and FIG. 2 is a diagram showing an example of a control flowchart thereof.
FIG. 3 is a diagram showing another example of the control flowchart, and FIGS. 4 to 6 are explanatory diagrams of a chopper mode in which time is plotted on the horizontal axis and motor applied voltage and motor rotational speed are plotted on the vertical axis. FIG. 4 is a diagram of the chopper mode 1, FIG. 5 is a diagram of the chopper mode 2, FIG. 6 is a diagram of the chopper mode 3, and FIG. 7 is a difference in the motor rotational speed in each case of idling, natural slip, and intentional slip. FIG. K ... Card, 1 ... Card entry / exit, 2 ... Drive roller, 3 ... Followed roller, 10 ... Motor, 13 ... Rotation detector, 20 ... Control device, 20A ... Slip determination means, 20B …
... Motor control means.

Claims (2)

[Claims] 1. A card transport device for transporting a card inserted into a device between a drive roller and a driven roller and rotating the drive roller with a motor to transport the card to the inside of the device. Means for judging slip when the card does not reach a predetermined position inside the apparatus even after a lapse of time, and when the means judges slip, the motor is intermittently rotated so that the drive roller and the card are relatively stationary. And a motor control unit that controls the chopper as described above. 2. A card transport device for transporting a card inserted into a device between a drive roller and a driven roller and rotating the drive roller by a motor, thereby changing the rotation of the motor. And a motor control means for controlling the chopper to intermittently rotate the motor so that the drive roller and the card are relatively stationary when the means determines that the slip occurs. And a card carrier.