JP2564340B2 - Medium transport method and device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a medium transport system, and in particular, paper sheets such as banknotes, passbooks, cut sheets used in bank terminal devices and recording sheets used in printers and the like. The present invention relates to a medium carrying system suitable for carrying a paper by a carrying means such as a rubber roller with high accuracy.

[Conventional technology]

Generally, in the transportation of paper sheets, since the feeding accuracy is influenced by the number of times of operation and the type of paper sheets handled, the feeding amount and the like are adjusted each time the vehicle is driven. Also,
As described in Japanese Utility Model Laid-Open No. 62-41553, a mode is selected for various media types by a plurality of modes that are predetermined based on the thickness of the conveyed paper and the number of the papers, and the paper feeding There is one that changes the torque of the motor.

[Problems to be solved by the invention]

In the above-mentioned conventional technique, the mode is selected for the type of paper by a plurality of modes determined in advance based on the thickness and the number of sheets, and the transport torque is controlled. The difference in friction coefficient between the transfer roller and the transfer roller due to the paper is not considered so much, and there is a problem in securing high feed accuracy. In particular, there is a problem in that a misalignment of printing or a smear due to slippage occurs in the passbook feeding in the bank terminal device or the recording paper feeding in the printer.

The present invention performs an initial parameter setting operation for automatically determining the control parameter of the medium feeding motor before the main operation of the medium feeding device, in which an unknown friction coefficient of paper is estimated, It is an object of the present invention to provide a medium transport system that can achieve the same feed amount regardless of the paper thickness, step difference, and friction coefficient of the medium.

[Means for solving problems]

The purpose is to store the fluctuation component of the pressing force with respect to the paper thickness of the medium as a parameter in advance in the data table, and use the equation of motion to describe the medium transportation, and to use the preliminary transportation stage before the main transportation stage. Based on the amount of slip measured in, the coefficient of friction of the medium is determined, and further, a calculation unit that determines the control parameters of the paper feed motor that creates the transport speed pattern to achieve the amount of slip at the time of predetermined transport ,
By setting the coefficient storage unit that stores the control parameters and the data storage unit that stores the slip amount, highly accurate medium conveyance control is achieved.

[Action]

The calculation unit that determines the control parameters of the paper feed motor is
Depending on various media, the control parameter values are determined such that the feed amount values are the same for all media. Then, the control parameter data is stored in the coefficient storage unit, and by sequentially sending the data to the motor drive unit, the paper feeding with the same accuracy is realized regardless of the type of the medium.

〔Example〕

As an example of the present invention, FIG. 1 shows a main part of a passbook carrying device in a normal printing device.

The passbook 1, which is a medium to be transported, is provided on the guide plate 10 which is a guide member by the first transporting means 5 and the second transporting means 15 which is appropriately separated from the first transporting means 5. Be transported.

The first conveying means 5 has a first driving roller 2 and a first driven roller 3 facing the first driving roller 2, and the second conveying means 15 has a second driving roller 12 And a second driven roller 13 facing the second driving roller 12. Each of the rollers 2, 3 and 12, 13 described above is, for example, a rubber roller whose surface has a high coefficient of friction.
The driven rollers 3 and 13 are supported by supporting members 4 and 14 such as springs, one end of which is fixed to the fixed frame 6. As a result, the first drive roller 2 and the first driven roller 3 and the second drive roller 12 and the second driven roller 13 convey the passbook 1 while sandwiching it from above and below in the figure. During transportation,
The first driven roller 3 and the second driven roller 13 follow the thickness of the passbook 1 by the support members 4 and 14 and freely move up and down.

A pulse motor 8 is connected to the second drive roller 12 as a transmission mechanism, for example, via a belt 7 as a drive unit. Although not shown, the first drive roller 2 and the second drive roller 12 are synchronously driven at the same speed by a transmission mechanism such as a belt or a gear. The first drive roller 2 and the second drive roller 12
May be driven in synchronization with each other by connecting a drive motor to each of them and controlling the speed and the like of these drive motors.

The first sensor 17 detects the position of the leading edge of the passbook 1 in the state of printing on the passbook 1, and detects the displacement of the passbook 1 with respect to the reference position when the passbook 1 is stopped, that is, the amount of slippage.

A line sensor or the like is used as the first sensor 17, for example. The second sensor 18 is provided in the vicinity of the first driven roller 3 between the first conveying means 5 and the second conveying means 15. This second sensor 18
The passbook 1 is for detecting that the stitch portion 1a is sandwiched between the first drive roller 2 and the first driven roller 3, and an optical sensor or the like is used, for example.

The control unit 20 controls driving of the pulse motor 8 described above. The control unit 20 includes a first sensor 17 and a second sensor 17
Signal processing unit 21 and signal processing unit 2 for processing signals from
A data storage unit 22 for storing data from 1, a calculation unit 23 for performing calculation based on various signals, a coefficient storage unit 24 for storing results calculated by the calculation unit 23, and this coefficient storage unit The drive unit 25 that controls the drive of the pulse motor 8 using the data of 24 and the correlation data of the thickness of the medium and the difference ΔW between the pressing force and the conveying force in advance, the position of the first driven roller 3 and the passbook step The storage unit 26 stores related data in a table. And these first
The sensor 17, the second sensor 18, and the control unit 20 measure the slip amount of various media in the pre-transport stage before entering the main transport stage, and based on the slip amount, determine the same transport amount for various media. I am trying to become.

First, the operation in the preliminary carrying stage will be described with reference to FIGS. 1 and 2. As an example, let us consider a case where a single slip and all pages of a passbook are transported on the same transport path.

First, in the first stage, a reference medium is designated among the mediums to be conveyed. Here, for example, a single form is designated.

When the reference medium is designated, the reference medium is then conveyed through the conveyance path shown in FIG.

A constant in the equation (1) describing the movement of the reference medium by the conveyance of the reference medium, that is, the friction coefficient μ ₁ of the reference medium is determined here. (Step (A)) Next, a method of determining the friction coefficient μ ₁ will be described.

Generally, when a medium having a mass m ₁ is conveyed by a rubber roller or the like at a constant speed pattern V ₁ , the medium feed amount or slip amount x ₁ is Is represented by

Here, m ₁ and w ₁ represent the mass of the medium and the pressing force of the driven roller at the time of transport, and F ₁ represents the resistance force of the medium in the transport direction.

In the step (A) described above, the velocity pattern V ₁ is made variable, the medium is conveyed for each velocity pattern, and the slip amount x ₁ of the medium at this time is measured, so that the inverse equation is obtained by using the equation (1). Estimate the friction coefficient μ ₁ . The data of the other parameters m ₁ , w ₁ , and F ₁ are stored in advance as a database in the storage unit.
Stored at 26. Then, the calculation is performed by the calculation unit 23 by sequentially referring to this database, and the friction coefficient μ
You will be looking for ₁ .

Then, the distribution of the slip amount x ₁ at this time is calculated in the data storage unit.
It is stored in 22 (step (B)), and the control parameter of the pulse motor 8 that achieves the speed pattern at this time is stored in the coefficient storage section 24. (Step (C)) Next, a passbook is conveyed, and the friction coefficient μ ₂ in a state in which an arbitrary number of pages are turned over is obtained as in the case of the single-cut sheet which is the reference medium. (Step (D)) In this case, the passbook is conveyed with the intermediate page open for comparison with a single slip.

The slip amount x ₂ of the passbook in this state is the same as that of 1 (equation) above. Is represented by

Here, m ₂ and w ₂ indicate the mass of the intermediate page of the passbook and the pressing force of the driven roller during conveyance, and F ₂ indicates the resistance force of the passbook in the conveyance direction.

The unknowns in equation (2) are μ ₂ and Δw ₁ . In the passbook, the thickness of the passbook changes as compared with the case of single-cut conveyance, and the pressing force of the conveyance rollers also changes. The aforementioned Δw ₁ is this change.

This data is data stored in the storage unit 26 in advance, and Δw ₁ is obtained based on this data.

The friction coefficient μ ₂ is the slip amount x ₂ measured by changing the speed pattern V ₂ as in the case of the above-mentioned step A.
Estimate by

Then, the distribution of the slip amount x ₂ at this time is stored in the data storage unit 22 (step E), and the control parameter of the pulse motor 8 that achieves the speed pattern at this time is stored in the coefficient storage unit 24. (Step F) Thereafter, in the same manner, the friction coefficients μ ₃ , μ _4, ... Of the sequentially passed passbooks are estimated.

In this way, the friction coefficient μ ₁ , μ _2, ... Estimating in an arbitrary page-turning state of the passbook is completed.

Next, the transport speed V _i with respect to the feed amount x _i of each page is calculated. (Step H) Since the coefficient of friction μ ₂ has already been obtained in order to obtain the transport speed V _i , Is represented by

Here, Δw _i differs depending on each page and each row, and its data is stored in the storage unit 26 in advance, and the parameter is determined based on this data. (Step G) Here, by arbitrarily changing the transport speed V _i ,
The right side of equation (3) and the right side of equation (1) are made equal. The control parameter of the pulse motor 8 that achieves the transport speed V _i when these are equal is stored in the coefficient storage unit 24. As a result, the transport speed pattern in the transport state of all pages is determined.

The control operation described above with reference to the flow chart of FIG.

FIG. 3 shows a flow chart of the algorithm executed by the arithmetic unit 23.

First, in the operation of the reference medium, the slip amount is measured based on the initial data m _i , V ₁ , t (step (1)), and then using the equation (1), the friction coefficient μ of the transport surface of the reference medium is measured. Estimate ₁ (step (2)). Next, the passbook is set, and the slip amount pattern x ₂ when the central page is open is measured by changing the transport speed pattern V ₂ , and the friction coefficient is calculated using the equations (step (3)) and (2). Estimate μ ₂ (step (4)). This estimation is performed under the setting of the fluctuation component Δw ₂ of the pressing force corresponding to the thickness of the open page of the passbook. Then, the determined friction coefficient μ ₂ is used to compare the slip amount pattern x ₁ when the reference medium is conveyed with the above-mentioned slip amount pattern x ₂ (step (5)). Then, the transport speed pattern V ₂ is sequentially changed until the difference becomes smaller than a predetermined minute value ε ₁ . Then, the slip amount pattern x ₂ when | x ₁ −x ₂ | <ε ₁ is stored in a predetermined place. At this time, the fluctuation component Δw ₂ of the pressing force w _i due to the thickness t of the medium for central page feeding is obtained from a data table as shown in FIG. 4, for example.

Similarly, the slip x _i at the time of carrying each i page of the passbook is measured by changing the carry speed pattern V _i (step (6)), and using the formula (3), the slip amount pattern x ₁ and the slip amount are measured. The pattern x _i is compared (step (7)). Then, the transport pattern V _i is determined so that the difference becomes smaller than a predetermined minute value ε ₂ . After determining the control parameters of the pulse motor for conveyance that achieves V _i on all pages, (step (8)) computing unit
The determination of the transport control parameter of the paper feed motor in 23 is completed.

As described above, when the control parameters of the pulse motor 8 for conveyance that achieves V _{i of} all pages are determined and the storage in the coefficient storage unit 24 is completed, the main conveyance stage is entered. At this main transport stage, as shown in FIG.
The passbook 1 is conveyed while being guided by the guide plate 10 by the first conveying means 5 and the second conveying means 15.

At the time of this conveyance, the thickness of the passbook 1 is detected by the second sensor 18, and the slip amount is obtained by the calculation unit 23 of the control unit 20 based on the friction coefficient and pressing force at that time, and corresponds to this slip amount. The control parameter is determined from the value stored in the coefficient storage unit 24. This control parameter is, for example, the gain of the motor, and the operation of the pulse motor is controlled based on this control parameter. The front end of the bankbook 1 being conveyed is always positioned at a predetermined position and is stopped. In this way, before the actual operation of the device, the operation to determine the gain of the transport motor and other control parameters is performed, so that the friction coefficient of the medium is unknown for any medium. Even so,
The same feed amount can be achieved regardless of the medium.
It can always be stopped at a fixed position.

As a result, for example, in a passbook printing apparatus, since the passbook can be opened and the conveyance can always be stopped at a fixed position irrespective of the location of the page, print misalignment does not occur and dirt due to slipping does not occur.

〔The invention's effect〕

As described above, according to the present invention, it is possible to achieve the same feed amount regardless of the paper thickness, step, and friction coefficient of the medium to be conveyed.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a flow chart for explaining an operation procedure of a pre-conveyance stage in the present invention, and FIG. 3 is a flow chart for explaining a decision algorithm of a calculation unit in the present invention. FIG. 4 is a diagram schematically showing an example of the contents of the data storage unit. 1 ... passbook, 5 ... first transport means, 8 ... motor, 15
...... Second conveying means, 17 ...... First sensor, 18 ...... Second
Sensor, 20 ... control unit, 21 ... arithmetic processing unit, 22 ... data storage unit, 23 ... arithmetic unit, 24 ... coefficient storage unit, 25 ...
Drive unit, 26 ... Storage unit.

Claims (5)

(57) [Claims] 1. A medium carrying method for carrying media having different friction coefficients by a carrying means such that the amount of slip between the carrying means and the medium becomes substantially constant during carrying based on the friction coefficient of the medium. The medium is conveyed by a preliminary conveying step of previously determining a control parameter of the driving means of the conveying means, and a main conveying step of conveying the medium using the control parameter obtained in the preliminary conveying step. A method of transporting a medium, which is performed. 2. The medium is conveyed by a preliminary conveying step of previously determining a control parameter of the driving means of the conveying means and a main conveying step of conveying the medium according to the control parameter obtained in the preliminary conveying step. In the medium transport method described above, the preliminary transport step includes a step of obtaining and storing a friction coefficient of the medium using a predetermined medium motion equation,
And a step of obtaining and storing a control parameter of the driving means for achieving the speed pattern at this time. 3. A transport means for transporting a medium while guiding the medium by a guide means, a first sensor for detecting an end portion of the medium when the medium stops at a predetermined position, and a thickness of the transported medium. The second sensor for detecting the height, the driving means for driving the conveying means, the signals from the first sensor and the second sensor, and the control parameter of the driving means obtained in advance in the preliminary conveying stage 2. A medium carrying device, comprising: a control unit for controlling the driving means so that the feeding amount of the same becomes the same feeding amount. 4. A conveying means for conveying a medium while guiding the medium by a guide means, a first sensor for detecting an end portion of the medium when the medium stops at a predetermined position, and a thickness of the medium to be conveyed. And a control parameter of the driving means for obtaining the same feed amount of the medium in the pre-conveying step and the second sensor for detecting the height are stored, and in the main conveying step,
A medium carrying device comprising a control unit for controlling the driving unit based on the stored control parameter. 5. A control parameter for controlling the drive of the driving means based on the control parameter is obtained and stored in the preliminary transporting step so that the control parameter of the drive means is obtained and stored so that the feed rate of the medium becomes the same. The unit includes a signal processing unit that processes a signal relating to the thickness of the medium to be conveyed and an end position when the medium is stopped, a data storage unit that stores data from the signal processing unit, a medium thickness, and a conveying unit. Based on the data from the storage unit, the drive unit that controls the drive of the drive unit, the data storage unit, and the storage unit, the control parameter for obtaining the optimum speed pattern of the drive unit is calculated. An arithmetic unit and a coefficient storage unit that stores the result calculated by the arithmetic unit are provided.
A medium carrying device, wherein the medium is carried by a control parameter selected from a large number of control parameters stored in the coefficient storage section according to the type and carrying state of the medium.