JPH0768895A - Impact printer - Google Patents

Abstract

PURPOSE:To automatically set the optimum gap adjusting mode by a method wherein gap adjusting modes, which are three ones set in advance every paper feeding route, are selected on the basis of the detection signal sent from a feeding paper sheet detection sensor. CONSTITUTION:The ON/OFF states of photosensors 1a, 1b and 1c are changed over when sensor light beam is broken by printing papers fed to respective paper feeding routes, resulting in sending in the form of detection signal emitted from a feeding paper route detection sensor 1 to a selecting means 2. In the selecting means 2, the gap adjusting code corresponding to the feeding paper route detected by the feeding paper route detection sensor 1 is selected on the basis of the mode setting conditions, which are set in advance in a gap adjusting mode setting section 3 so as to transfer the selected gap adjusting mode to a gap adjusting means 5. Thus, the gap adjusting means 5 acts in accordance with the gap adjusting mode selected by the selecting means 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has three paper feed routes as a route for feeding printing paper between a print head and a platen, and a gap adjustment for adjusting a gap between the print head and the platen. The present invention relates to an impact printer having three mode functions as modes.

[0002]

2. Description of the Related Art Generally, in the structure of an impact printer, a gap (hereinafter, referred to as a gap between a print head and a platen)
The print gap, which is called the print gap, has a range in which good printing can be performed due to factors such as running stability of the print paper and mechanical response characteristics of the print wire in the print head. A mechanism for adjusting the print gap is provided. Usually, the print gap can be set to be several steps wide, and the operator sets the number of gap steps according to the paper thickness of the print paper to perform printing. This setting of the number of gap steps was done manually by an operator, but as the printer's functionality and added value continue to increase,
Various so-called auto gap methods, which can automatically set the optimum print gap, have been devised and put into practical use.
In such an auto gap method, it is essential to detect the paper thickness of the printing paper fed between the print head and the platen in order to obtain the optimum printing gap.

FIG. 6 is a schematic diagram for explaining a paper thickness detection method for a typical print paper. First, in the figure, a pressure sensor 12 is installed between the platen 10 and the print head 11 at a position where the fed print paper P is sandwiched. The pressure sensor 12 is movably supported by a sensor moving mechanism (not shown) in the direction of the platen 10 shown by an arrow in the figure. At the time before feeding, the pressure sensor 12 moves to the platen 10 and detects the position of the platen 10,
The distance from the initial position of the pressure sensor 12 to the platen 10 is measured, and this is stored in the memory as reference data.
After that, when the printing paper P is fed, the pressure sensor 12 again moves to the platen 10 side and measures the distance from the initial position to the printing paper P. The paper thickness of the print paper P is detected by comparing the measured data obtained here with the reference data stored in the memory. Then, the print gap is set to the optimum gap by operating a print gap automatic adjustment mechanism (not shown) based on the paper thickness detection data.
It should be noted that the print head 1 is
A system in which the tip of the sheet 1 is brought into contact with the platen 10 or the print sheet P to detect the sheet thickness has also been put into practical use.

Furthermore, as a method for detecting the thickness of the printing paper, the following method has been put into practical use. Figure 7
FIG. 6 is a half cross-sectional view of a so-called sensor print head in which a sensor is built in the print head. In the structure of the print head 20 shown in the figure, the armature 22 fixed to the free end side of the spring 21 is composed of an armature yoke 23, a spring 21, a spacer 24, an upper yoke 25, a magnet 26, a lower yoke 27, a base 28, and a core 29. It is a component of a circuit. Therefore, during non-printing, the armature 22 is attracted to the core 29 side by the magnetic flux passing between the core 29-spring 21 and the armature 22. On the other hand, at the time of printing, by energizing the coil 30, the magnetic flux attracting the armature 22 is canceled and the armature 22 is opened, so that the spring 21 is also released from the state of being bent by the thickness of the spacer 24. Then, together with the armature 22, the movement starts upward in the drawing. Here, since the print wire 31 is fixed to the tip of the armature 22, it operates together with the armature 22. That is, the printing wire 31 is
Guide nose 33 while being guided by wire guide 32
Vigorously projects from the front end of the sheet and collides with the print sheet through an ink ribbon (not shown) to print.

On the other hand, a sensor board 34 is arranged at a position facing the armature 22.
An electrode 35 is provided on the surface 4. The electrode 35 and the armature 22 form a kind of capacitor.
Therefore, if the change in the electrostatic capacitance due to the operation of the armature 22 is detected, the time from the start of the movement of the armature 22 to the collision of the printing wire 31 with the printing paper (hereinafter referred to as printing time) is detected. be able to.

Therefore, when actually detecting the paper thickness, the reference printing time is first measured. Since this measurement is performed in the state where the printing paper is not fed, the printing wire 31 collides with the platen via the ink ribbon (not shown). This operation is performed for each print wire 31, and the print time data of each print wire 31 is stored in the memory as reference data. Next, after feeding the print paper and receiving the print data from the host computer, select the desired number of dots from the dots to be printed on the first line of the print data, perform preliminary printing, and print as described above. Measure time. The difference between this printing time and the reference printing time stored in the memory is proportional to the paper thickness of the printing paper (the larger the time difference, the thicker the paper thickness,
The smaller the time difference is, the thinner the paper thickness is. Therefore, the paper thickness of the print paper can be detected by the arithmetic processing based on the difference between the printing times of the two. Therefore, the print gap is set to the optimum gap by operating the gap adjusting mechanism (not shown) based on the thus detected paper thickness data.

Further, in the conventional serial printer, the gap adjustment mode for adjusting the print gap is an automatic gap adjustment mode for adjusting the gap for each print sheet, and the gap for only the first print sheet supplied after the power is turned on. Some have three mode functions: a semi-automatic gap adjustment mode for adjustment and a manual gap adjustment mode for gap adjustment by operator operation. In general, when the thickness of paper to be used changes frequently such as cut sheets and copy paper, it is necessary to detect the thickness of each sheet and adjust the gap, and thus the ode gap adjustment mode is suitable. Also, when using several continuous sheets of the same paper thickness such as cut sheets and copy paper, or when using continuous paper, the paper thickness is detected only for the first printing paper supplied. The semi-automatic gap adjustment mode is suitable because you only have to adjust the gap by adjusting the gap.

On the other hand, in the case of the same paper such as copy paper and envelope used for slips, which has different paper thickness depending on the location (hereinafter referred to as special paper), the auto gap adjustment mode or the semi-auto gap adjustment is performed. When the mode is set, when the print gap is automatically adjusted based on the paper thickness data detected in the thin paper part, the gap between the print head and print paper becomes too narrow in the thick paper part, The rubbing with the ribbon may cause the printing paper to be contaminated, or a paper jam may occur to interrupt the printing process. For this reason, when handling special sheets, the manual gap adjustment mode in which the operator can set the desired number of gap steps is suitable so as not to cause the above-mentioned problems.

Further, in the past, as a route for feeding a print sheet between the print head and the platen,
Some have multiple paper feed routes. FIG. 8 is a schematic diagram showing this type of printer configuration. In the illustrated printer configuration, as the plurality of paper feed routes, a top feed paper feed route R1 for feeding the print paper P1 from above the platen 10 and a print paper P from the rear side of the platen 10 are used.
It has three paper feed routes, a rear feed paper feed route R2 for supplying 2 and a bottom feed paper feed route R3 for supplying the printing paper P3 from below the platen 10. Usually, a cut sheet P1 such as a cut sheet is supplied through a top feed paper feed route R1 wound around the platen 10 about half a round, and a continuous paper P2 provided with perforations.
Are supplied through the rear feed paper feed route R2 wound around the platen 10 for about 1/4 round.

On the other hand, when a printing paper P3 having a certain thickness or more such as thick paper, copy paper, or sticker paper is used, the rigidity of the entire paper becomes high, so that the platen 10 cannot be tightly adhered and wound. . Therefore, in the case of the print paper P3 having a certain thickness or more, the print paper P3 is supplied through the bottom feed paper feed route R3 which can be fed without being wound around the platen 10. Further, even if the same paper is a special paper having a different paper thickness depending on the location, it is supplied through the bottom feed paper feed route R3. In this way, usually a suitable paper feed route is determined for each type of printing paper,
The operator uses different paper feed routes according to the type of printing paper used.

[0011]

However, in the above-mentioned conventional serial printer, although the gap adjustment mode can be freely set by the operation of the operator, once the gap adjustment mode is set, the print sheet is supplied from any paper feeding route. Since the same applies when it is supplied, for example, while printing in the semi-auto gap adjustment mode on the continuous paper supplied from the rear feed paper feed route R2, only one sheet is cut from the top feed paper feed route R1. If you want to supply and print the cut sheets, switch the gap adjustment mode setting from the semi-auto gap adjustment mode to the auto gap adjustment mode or the manual gap adjustment mode before using the cut sheets and finish printing the cut sheets. , Again the gap adjustment mode to the original semi-auto gap adjustment mode Etc. it is necessary to reset, there is a troublesome that must be re-set the gap adjustment mode by the operator operation every time the printing paper handling changes and paper feed route changes.

The present invention has been made to solve the above problems, and an impact printer capable of automatically setting an optimum gap adjustment mode corresponding to a paper feed route to which print paper is actually supplied. The purpose is to provide.

[0013]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and a printing paper is fed from above the platen as a paper feeding route for feeding the printing paper between the printing head and the platen. It has three paper feed routes: a top feed paper feed route that supplies paper, a rear feed paper feed route that supplies printing paper from the back side of the platen, and a bottom feed paper feed route that supplies printing paper from below the platen. A gap adjustment mode that adjusts the gap between the head and the platen, an auto gap adjustment mode that adjusts the gap for each print sheet, and a semi-auto gap adjustment that adjusts the gap only for the first print sheet supplied after power is turned on. Manual gap adjustment mode 3 in which the gap is adjusted by the mode and operator operation In the impact printer equipped with the mode function of, the paper feed route detection sensor that detects which of the three paper feed routes the printing paper is fed, and the detection signal from the paper feed route detection sensor On the basis of this, there is provided a selecting means for selecting a preset gap adjustment mode for each of the three paper feed routes. Further, the printing conditions differ depending on the paper thickness of the printing paper for each of the three paper feed routes.

[0014]

In the impact printer of the present invention, the paper feed route detection sensor detects from which of the three paper feed routes the printing paper is fed, and the selection means operates based on the detection signal. Since the preset gap adjustment mode is selected for each paper feed route, the optimum gap adjustment mode is automatically set according to the paper feed route to which the printing paper is actually fed during the printing process. Become. Further, since the setting number of the printing gap corresponding to the paper thickness of the printing paper and the setting condition of the corresponding printing speed are different for each printing route, not only plain paper but also special printing paper is handled. Good printing can be performed.

[0015]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram showing the functional configuration of an embodiment of a serial printer according to the present invention. First, as the configuration of the printer, as shown in FIG. 2, as a paper feed route for feeding the print paper between the print head 11 and the platen 10, a top feed paper feed for feeding the print paper P1 from above the platen 10 is used. Route R1, rear feed paper feed route R2 for supplying print paper P2 from the back side of platen 10 and bottom feed paper feed route R3 for supplying print paper P3 from below platen 3
It has one paper feed route. The gap adjustment mode for adjusting the print gap is an auto gap adjustment mode for adjusting the gap for each print sheet, a semi-auto gap adjustment mode for adjusting the gap only for the first print sheet supplied after the power is turned on, and an operator. It is equipped with three mode functions: a manual gap adjustment mode in which gap adjustment is performed by operation.

In the configuration of this embodiment, as shown in FIG. 1, one of the three paper feed routes R1, R2 and R3 described above is used to detect which paper feed route the print paper is fed to. The route detection sensor 1 and the selection means 2 for selecting a preset gap adjustment mode for each of the three sheet feeding routes R1, R2, R3 based on a detection signal from the sheet feeding route detection sensor 1 are provided. Has been done. The paper feed route detection sensor 1 includes, for example, as shown in FIG. 2, three optical sensors 1a, 1b, 1 arranged for each paper feed route.
each of the optical sensors 1a, 1b, 1
In c, the printing paper supplied to each paper feed route switches the on / off state by blocking the sensor light beam, and this becomes a detection signal (on / off signal) from the paper feed route detection sensor 1 to the selection means 2. Sent out. Therefore, the selection unit 2 can determine from which paper feed route the printing paper is supplied, depending on which one of the three photosensors 1a, 1b, 1c sends the detection signal.

On the other hand, the gap adjustment mode setting section 3 includes
The gap adjustment mode is set in advance for each of the paper feed routes R1, R2, R3. The mode setting information in the gap adjustment mode setting unit 3 is read by the selection unit 2 as needed. Further, the mode setting conditions in the gap adjustment mode setting unit 3 can be variously set by the operator via the mode setting input unit 4, for example, by menu setting by an operator panel, mechanical lever operation, or a function code from the host computer. It is possible to change the conditions.

Then, the selecting means 2 selects the gap adjusting mode corresponding to the paper feeding route detected by the paper feeding route detecting sensor 1 based on the mode setting condition preset in the gap adjusting mode setting section 3. Then, the selected chap adjustment mode is transferred to the gap adjusting means 5. As a result, the gap adjusting means 5 operates according to the gap adjusting mode selected by the selecting means 2.

FIG. 3 is a diagram showing an example of mode setting conditions in the gap adjustment mode setting section. First, in the case of Example 1, when the print paper is supplied through the top feed paper feed route R1, the semi-auto gap adjustment mode is set, when the print paper is supplied through the rear feed paper feed route R2, the automatic gap adjustment mode is set, and When the printing paper is supplied through the bottom feed paper feed route R3, the manual gap adjustment mode is set. The mode setting conditions of Example 1 are as follows. Cut paper having the same paper thickness is used in the top feed paper feed route R1, continuous paper of which the paper thickness is not determined is used in the rear feed paper feed route R2, and bottom feed paper feed is performed. The route R3 is suitable for using special paper.

On the other hand, in the case of Example 2, when the print paper is supplied through the top feed paper feed route R1, the manual gap adjustment mode is set, and when the print paper is supplied through the rear feed paper feed route R2, the semi-automatic gap adjustment is performed. Mode, when the print paper is supplied through the bottom feed paper feed route R3, the semi-auto gap adjustment mode is set. The mode setting conditions of Example 2 are
The top feed paper feed route R1 uses a cut sheet feeder to use a large number of envelopes with an optimal number of gap stages, for example, four, and the rear feed paper feed route R2 and the bottom feed paper feed route R3 use print sheets of a particular size. It is suitable when the type is not decided.

Further, since the printing paper supplied through the bottom feed paper feed route R3 is often a special paper, when the operator sets the number of gap steps in the manual gap adjusting mode, the running stability of the printing paper and the prevention of dirt are required. Considering this, the print gap is set to be slightly wider than when the paper is fed through the top feed paper feed route R1 or the rear feed paper feed route R2. Similarly, even when the gap adjustment mode corresponding to the bottom feed paper feed route R3 is set to the automatic gap adjustment mode or the semi-auto gap adjustment mode, the top feed paper feed route R1 or the rear feed paper feed route R2 is used. The print gap is set wider than when feeding paper.

FIG. 4 is a diagram showing the setting conditions of the number of gap steps according to the paper thickness for each sheet feeding route, and FIG. 5 shows the setting conditions of the printing speed according to the number of gap stages for each sheet feeding route. It is a figure. As can be understood from the figure, the paper thickness corresponding to each number of gap steps is set to be 0.5 mm thinner in the bottom feed paper feed route R3 than in the top feed paper feed route R1 and the rear feed paper feed route R2. ing. Therefore, for example, even when the paper thickness is 0.23 mm, the top feed sheet feeding route R1 and the rear feed sheet feeding route R2 have four gap stages and the bottom feed sheet feeding route R3 has a wider gap of five stages. Is set to.

Also, regarding the relationship between the number of gap steps and the printing speed, in the top feed paper feed route R1 and the rear feed paper feed route R2, the first to third stages are 100%, the fourth to sixth stages are 80%, and the seventh stage is 7 steps. In the bottom feed paper feeding route R3, 100% of the 1st and 2nd trays are 80% of the 3rd to 5th trays, and 50% of the 6th and subsequent trays.
%. Therefore, for example, even when the number of gap steps is set to the same three steps, the printing speed is 1 in the top feed paper feed route R1 and the rear feed paper feed route R2.
The bottom feed sheet feeding route R3 is set to 00%, which is later than 80%.
Similarly, regarding the coil energization time of the print head, although not shown, the bottom feed paper feed route R3 is set to be slightly longer than the top feed paper feed route R1 and the rear feed paper feed route R2. It has become.

The reason for changing the setting number of print gaps and the setting conditions of print speed according to the paper thickness for each paper feed route is called special paper as described in the prior art example. This is because most of the paper that is fed is fed through the bottom feed paper feed route R3. In other words, for special paper, the printing gap is set wider considering the running stability of the printing paper and the prevention of stains. Impact strength becomes weak. Therefore, when the paper is fed through the bottom feed paper feed route R3, the printing speed is slowed or the coil is energized for a long time to obtain a sufficient impact force over the entire surface of the paper as described above.

[0025]

As described above, according to the impact printer of the present invention, the paper feed route detection sensor detects the paper feed route of the print paper for the print paper fed from the arbitrary paper feed route. Based on this detection signal, the selection means selects the gap adjustment mode preset for each paper feed route, so that the print paper is actually fed to the paper feed route during the printing process. Accordingly, it becomes possible to automatically set a gap adjustment mode suitable for it. As a result, it is not necessary for the operator to switch the gap adjustment mode each time the paper feed route is changed or the type of print paper to be handled is changed, thereby eliminating the conventional troublesome setting of the gap adjustment mode. Further, since the setting number of the printing gap according to the paper thickness of the printing paper and the setting condition of the corresponding printing speed are different for each paper feeding route, even when handling not only plain paper but also special paper, As described above, excellent printing can be performed on various types of printing paper without requiring complicated setting work.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a functional configuration of a printer according to an embodiment.

FIG. 2 is a schematic diagram illustrating a printer configuration according to an embodiment.

FIG. 3 is a diagram showing an example of mode setting conditions in a gap adjustment mode setting unit.

FIG. 4 is a diagram showing setting conditions of the number of gap stages according to the sheet thickness for each sheet feeding route.

FIG. 5 is a diagram showing setting conditions of a printing speed according to the number of gap stages for each paper feed route.

FIG. 6 is a diagram for explaining a paper thickness detection method for a typical print paper.

FIG. 7 is a half sectional view of a sensor print head.

FIG. 8 is a schematic diagram showing a printer configuration in a conventional example.

[Explanation of symbols]

 1 Paper feed route detection sensor 1a to 1c Optical sensor 2 Selector 10 Platen 11 Print head R1 Top feed paper feed route R2 Rear feed paper feed route R3 Bottom feed paper feed route P1 to P3 Print paper

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takanori Mimura 1-7-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd. (72) Inventor Yoshihiko Shimosugi 1-12-12 Toranomon, Minato-ku, Tokyo No. Oki Electric Industry Co., Ltd.

Claims (2)

[Claims] 1. A top feed paper feed route for feeding print paper from above the platen as a paper feed route for feeding print paper between the print head and the platen, and a print paper from the back side of the platen. And a bottom feed paper feeding route for feeding printing paper from below the platen, and as a gap adjusting mode for adjusting the gap between the print head and the platen. , Automatic gap adjustment mode to adjust the gap for each print paper,
In an impact printer having three mode functions, a semi-automatic gap adjustment mode in which gap adjustment is performed only on the first print sheet supplied after power is turned on, and a manual gap adjustment mode in which gap adjustment is performed by operator operation. Of the paper routes, based on a paper feed route detection sensor that detects which paper feed route the print paper is supplied, and a detection signal from the paper feed route detection sensor,
An impact printer comprising: a selection unit that selects a preset gap adjustment mode for each of the three paper feed routes. 2. The set number of print gaps according to the paper thickness of the print sheet and the print speed setting condition corresponding to the set number of print gaps are different for each of the three paper feed routes. The impact printer according to claim 1, wherein: