JP2001047717A - Residual quantity detector for ink ribbon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use up an ink ribbon to the maximum by detecting the residual quantity and the end of the ink ribbon with high accuracy. SOLUTION: A rotary encoder 8 comprises a sensor plate 8a coupled with the ink ribbon bobbin 7 in a print mechanism 1 employing an ink ribbon 4 to rotate integrally therewith, and a section 8b for counting the rotational quantity of the sensor plate 8a as the number of pulses. Based on the difference between the accumulated number of pulses counted by the rotary encoder 8 and a number of pulses for defining the end preset in correspondence with the overall length of the ink ribbon 4, residual quantity of ink ribbon is detected and a decision is made that the end of ink ribbon is reached when the residual quantity of ink ribbon is 0.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink ribbon remaining amount detecting device capable of detecting the remaining amount of an ink ribbon with high accuracy in a printing mechanism using an ink ribbon.

[0002]

2. Description of the Related Art As a conventional example of a printing mechanism using an ink ribbon, there is, for example, a thermal transfer printer. In a thermal transfer printer, black and white printing can be performed using a black ink ribbon, and color printing can be performed using ink ribbons corresponding to each of the three primary colors.

As a mechanism for detecting the end of the ink ribbon in such a conventional printing mechanism using an ink ribbon, for example, an actuator portion of a switch for detecting the end of the ink ribbon is brought into contact with the winding end of the ink ribbon, and the end of the ink ribbon is detected. It is common to use a structure in which the position of the actuator section moves in the radial direction as the remaining amount decreases, and the contact of the switch is closed when the remaining amount of the ink ribbon decreases to a predetermined margin. It is. By using such an ink ribbon end detection mechanism, it is possible to detect that the remaining amount of the ink ribbon has decreased to a predetermined margin, that is, to detect the end of the ink ribbon.

[0004]

In recent years, as the development of the material used for the ink ribbon has progressed, the thickness of the ink ribbon has tended to become thinner. In some cases, the total length of the ink ribbon is increased due to the thinning. When such ink ribbons having different film thicknesses are mixedly used, in the above-described conventional end detection method, it is determined that the end of the ink ribbon has arrived when the diameter of the used ink ribbon decreases to a predetermined value. Therefore, if the predetermined margin is set to be appropriate for a thick ink ribbon, the predetermined margin becomes excessive for a thin ink ribbon, The end is detected even though the ink ribbon remaining enough to withstand use remains. Therefore, improvement in detection accuracy has been desired.

A first object of the present invention is to detect the remaining amount of the ink ribbon with high accuracy. A second object of the present invention is to make it possible to use the ink ribbon effectively and without waste by detecting the end of the ink ribbon with high accuracy.

[0006]

In order to achieve the first object,
According to a first aspect of the present invention, a rotary member includes a rotating member coupled to an ink ribbon bobbin of a printing mechanism using an ink ribbon so as to rotate integrally with the ink ribbon bobbin, and a counting unit that counts the amount of rotation of the rotating member as a pulse number. An encoder is provided, and a remaining amount detecting means for detecting the remaining amount of the ink ribbon based on the total number of pulses counted by the rotary encoder and the total length of the ink ribbon is provided.

According to a second aspect of the present invention, for the second object, the remaining amount detecting means stores an end defining pulse number preset corresponding to the entire length of the ink ribbon. A definition pulse number storage unit, a total pulse number storage unit for storing the total pulse number counted by the rotary encoder, and a terminal definition pulse number stored in the terminal definition pulse number storage unit and stored in the cumulative pulse number storage unit And an end determining unit that calculates the remaining amount of the ink ribbon based on the total number of pulses and determines the end based on the remaining amount of the ink ribbon.

In the first invention, when printing is performed by a printing mechanism using an ink ribbon, the counting unit uses the amount of rotation of the rotating member coupled to the ink ribbon bobbin as the number of pulses when the rotating member integrally rotates. By counting, the rotating member and the counting section function as a rotary encoder. Meanwhile, the remaining amount detecting means detects the remaining amount of the ink ribbon based on the total number of pulses counted by the rotary encoder and the total length of the ink ribbon. It is possible to manage in real time, and it is possible to improve the accuracy of detecting the remaining amount of the ink ribbon.

In the second invention, the terminal definition pulse number storage unit, which is a component of the remaining amount detecting means, stores a terminal definition pulse number preset in correspondence with the entire length of the ink ribbon. The total number of pulses counted by the rotary encoder is stored in the total pulse number storage unit that is a component of the amount detection unit, and the termination determination unit that is a component of the remaining amount detection unit includes the termination definition pulse number and the Since the remaining amount of the ink ribbon is calculated based on the total number of pulses and the termination is determined based on the remaining amount of the ink ribbon, even when an ink ribbon having a different film thickness is used, the termination at the winding end of the ink ribbon is performed. It is unlikely that the ink ribbon remaining amount at the end detection differs as in the conventional example of the structure in which the actuator part of the detection switch is brought into contact. There. Therefore, the accuracy of detecting the remaining amount of the ink ribbon and the accuracy of detecting the end of the ink ribbon can be improved, and the ink ribbon can be used effectively to the maximum without waste.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a plan view conceptually showing a mechanism system of a printing mechanism incorporating the ink ribbon remaining amount detecting device of the first embodiment of the present invention, and FIG. 2 is a schematic diagram of a control system of the printing mechanism of the first embodiment. FIG. 3 is a block diagram illustrating a configuration.

The mechanism of the printing mechanism 1 of the present embodiment is shown in FIG.
As shown in FIG.
b, the printing paper 3 wound in a roll shape
Printing paper driving device 2 for feeding in the direction, and ink ribbon 4
Ribbon driving device 5 for winding up in the direction of arrow B in the drawing
A print head driving device (not shown) for driving the print head 6, and a sensor plate 8a and a sensor plate 8 which are rotating members coupled to the ink ribbon bobbin 7 so as to rotate integrally therewith.
a counting unit 8 for counting the rotation amount of a as a pulse number
It consists b, formed by and a rotary encoder 8 for counting the consumption L _U of the ink ribbon 4 as the cumulative number of pulses P _A. The ink ribbon 4, the ink ribbon driving device 5, the print head 6 (and the print head driving device), and the rotary encoder 8 perform color printing using, for example, ink ribbons corresponding to each of the three primary colors and black. When the printing mechanism 1 is configured, four sets are provided.

The control system of the printing mechanism 1 of the present embodiment is shown in FIG.
As shown in FIG. 5, a printing paper driving circuit 11 for driving the printing paper driving device 2, an ink ribbon driving circuit 12 for driving the ink ribbon driving device 5, and a printing head for driving the printing head driving device a drive circuit 13, terminating defined pulse number storage section 14 for storing a preset end defined pulse number P _L corresponding to the entire length L of the ink ribbon 4
When a cumulative pulse number storage section 15 for storing the cumulative pulse number P _A counted by the rotary encoder 8, stored in the terminating defined pulse number P _L and cumulative pulse number storage section 15 is stored in the end-defined pulse number storage section 14 the termination determined by whether or not reached the remaining number of pulses P _R 0 as well as calculating the remaining amount pulse number P _R corresponding to the ink ribbon remaining amount (L-L _U) based on has been accumulated pulse number P _a It comprises a termination determining unit 16 for performing operations and a control unit 17 for performing operation control and input / output of various signals with respect to each of the above components. In the case where the printing mechanism 1 is configured to perform color printing using the ink ribbon corresponding to each of the three primary colors and black, for example, the ink ribbon drive circuit 12 and the print head drive circuit 13 each have four sets. Shall be provided.

The following method is used to store the number of end-defined pulses P _L preset in correspondence with the total length L of the ink ribbon of each color used in the printing mechanism 1 in the end-defined pulse number storage section 14. is there. (1) When the full length data of the ink ribbon is input to the control unit 17 by external input means such as a keyboard, the control unit 17 automatically calculates a value obtained by subtracting the number of pulses corresponding to the margin from the pulse number conversion value of the full length data. Generated, which is the number of defined end pulses P
It is stored in the terminal definition pulse number storage unit 14 as _L. (2) The product identification numbers of all the ink ribbons that can be used in the printing mechanism 1 (assuming that the ink ribbons of different colors and different manufacturing rods have different product identification numbers) are associated with the entire length. A database is constructed in advance, and when the product identification number is selectively input from an external input means such as a keyboard or the barcode attached to the outer box of the ink ribbon is read and input, the control unit 17 performs the same operation as described above. Is stored in advance.

Next, printing control including control for detecting the remaining amount of ink ribbon in the printing mechanism 1 of the present embodiment will be described with reference to FIGS. FIG. 3 is a flowchart showing the initialization control in the printing mechanism of the first embodiment. This initialization control is executed when a new ink ribbon is set for exchanging the ink ribbon. First, in step 51 of FIG. 3, it clears the cumulative pulse number P _A which is stored in the cumulative pulse number storage section 15. In the next step 52, it stores the preset end defined pulse number P _L corresponding to the entire length L of the current set ink ribbon to the end defined pulse number storage section 14.

FIG. 4 is a flowchart showing printing control including control for detecting the remaining amount of ink ribbon in the printing mechanism according to the first embodiment. This printing control is performed during a printing operation. First, at step 61 in FIG. 4, it is checked whether or not a print command has been issued from the control unit 17 to the printing mechanism 1. Only when a print command has been issued, control is performed at step 6.
Proceed to 2. In step 62, the printing paper 3 and the ink ribbon 4 are driven synchronously and sent out in the directions of arrows A and B in FIG. 1, respectively. At the same time, when the print head 6 is driven according to the print content in the next step 63, the ink of the ink ribbon 4 is transferred to the printing paper 3 and printing according to the print content is performed.

While the printing is being performed, the sensor plate 8a coupled to the ink ribbon bobbin 7 rotates with the rotation of the ink ribbon bobbin 7 on the sending side, and the amount of rotation of the sensor plate 8a is counted by the counting unit 8b to determine the pulse number. Is counted as Thus the number of pulses counted by the rotary encoder 8 in the are sequentially added, because it is updated and stored in the cumulative pulse number storage section 15 as a total pulse number P _A at step 64, the cumulative pulse number P _A is up to that point in time This indicates the consumption amount (feed amount) L _U of the ink ribbon 4.

In the next step 65, the termination determining section 16 determines the number of termination pulses P _L stored in the termination pulse number storage section 14 and the total pulse number P _A stored in the cumulative pulse number storage section 15. Ink ribbon remaining (L
The number of remaining pulses P _R = P _L -P _A corresponding to −L _U ) is calculated, and in the next step 66, it is determined whether or not the number of remaining pulses P _R has reached 0. This determination is NO (P _R > 0)
If so, since the end of the ink ribbon has not yet been reached, the control is returned to step 61 and thereafter, and the above printing operation is repeated. If YES (P _R = 0), the end of the ink ribbon has been reached. Since this is the case, the control proceeds to the next step 67. In step 67, the termination determination is performed, and the termination detection signal is transmitted from the termination determination unit 16 to the control unit 17.
Return to. Then, in the next step 68, the control unit 1
7 based on a command from the printer 7 (printing paper drive 2
And the operation of the ink ribbon driving device 5 and a warning message indicating that the ribbon has run out are performed.

According to the printing mechanism 1 of the present embodiment, the difference between the number of pulses P _L defined at the end corresponding to the total length L of the ink ribbon 4 and the total number of pulses P _A counted by the rotary encoder 8 is used. A certain remaining pulse number P
_{Since the} remaining amount of the ink ribbon is detected by _R , the remaining amount of the ink ribbon that changes every moment according to the consumption of the ink ribbon can be managed in real time, and the remaining amount of the ink ribbon can be detected with high accuracy.

Further, since it is determined that reaches the end of the ink ribbon when the remaining number of pulses P _R reaches 0, it is possible to perform end detection of the ink ribbon with high accuracy. Therefore, even when ink ribbons having different film thicknesses are used, the ink ribbon remaining at the time of detecting the end is different from the conventional example in which the actuator of the switch for detecting the end is brought into contact with the winding end of the ink ribbon. The ink ribbons can be used to the maximum extent possible without waste, without the problem of different amounts. Further, by previously setting the terminated separately defined pulse number P _L respectively different ink ribbon overall length, it is always possible to use to terminate a multi-type of the ink ribbon.

[0020]

As described above, according to the first aspect, the remaining amount of the ink ribbon is detected based on the total number of pulses counted by the rotary encoder and the total length of the ink ribbon. The remaining amount of the ink ribbon that changes every moment can be managed in real time, and the accuracy of detecting the remaining amount of the ink ribbon can be improved.

According to the second aspect of the present invention, the remaining amount of the ink ribbon is calculated based on the predetermined number of defined end pulses corresponding to the entire length of the ink ribbon and the total number of pulses, and the termination is determined based on the remaining amount of the ink ribbon. Therefore, even when ink ribbons having different film thicknesses are used, it is possible to detect the remaining amount and the end of the ink ribbon with high accuracy. Therefore, the ink ribbon can be reliably used up to the end, and the ink ribbon can be used stably up to the usage limit.

[Brief description of the drawings]

FIG. 1 is a plan view conceptually showing a mechanism system of a printing mechanism incorporating an ink ribbon remaining amount detecting device according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a schematic configuration of a control system of a printing mechanism according to the first embodiment.

FIG. 3 is a flowchart illustrating initialization control in the printing mechanism according to the first embodiment.

FIG. 4 is a flowchart illustrating print control including ink ribbon remaining amount detection control in the printing mechanism of the first embodiment.

[Explanation of symbols]

 Reference Signs List 1 printing mechanism 2 printing paper driving device 2a paper driving unit 2b paper feeding roller 3 printing paper 4 ink ribbon 5 ink ribbon driving device 6 print head 7 ink ribbon bobbin 8 rotary encoder 8a sensor plate (rotating member) 8b counting unit 11 printing paper driving Circuit 12 Ink ribbon drive circuit 13 Print head drive circuit 14 Termination definition pulse number storage unit 15 Cumulative pulse number storage unit 16 Termination determination unit 17 Control unit

Claims (2)

[Claims] 1. A rotary encoder comprising a rotating member coupled to an ink ribbon bobbin of a printing mechanism using an ink ribbon so as to rotate integrally therewith, and a counting section for counting the amount of rotation of the rotating member as the number of pulses. An ink ribbon remaining amount detecting device, comprising: a remaining amount detecting means for detecting the remaining amount of the ink ribbon based on the total number of pulses counted by the rotary encoder and the total length of the ink ribbon. 2. The remaining amount detection means includes a terminal definition pulse number storage unit that stores a preset terminal definition pulse number corresponding to the entire length of the ink ribbon, and a total pulse number counted by the rotary encoder. A cumulative pulse number storage section for storing, and a remaining ink ribbon remaining amount calculated based on the terminal definition pulse number stored in the terminal definition pulse number storage section and the cumulative pulse number stored in the cumulative pulse number storage section. 2. The ink ribbon remaining amount detecting device according to claim 1, further comprising an end determining unit that performs an end determination based on the remaining amount of the ribbon.