JP3284452B2 - Impact printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an impact printer for controlling a printing operation according to the temperature of an impact head.

[0002]

2. Description of the Related Art In a conventional impact printer,
In order to prevent the coil from being burned out due to the heat generated by the impact head, a temperature sensor is attached to the impact head as shown in Japanese Utility Model Application Laid-Open No. 58-136339, and printing operation is continued when the detected temperature is lower than a predetermined set temperature. When the temperature was high, printing was stopped until the detected temperature dropped below the set temperature.

[0003]

However, when high-duty printing is performed, printing is stopped in a short time from the start of printing, or the temperature of the impact head rapidly rises. Due to the thermal inertia, the set temperature is greatly exceeded, and it takes a long time until the temperature falls below the set temperature again, and the time until printing is restarted is long, causing data communication errors with the host computer. However, there is a problem that the user feels strange.

[0004]

In order to solve such a problem, an impact printer of the present invention drives an armature by an electromagnet and performs printing by a printing wire engaged with a tip of the armature. In the impact printer which includes a temperature sensor for detecting the temperature of the impact head and control means for controlling a printing operation in accordance with the temperature detected by the temperature sensor, the printing of one line is started in an impact printer which performs printing for each line. Before, the temperature sensor
A first determination is made as to whether or not the detected temperature exceeds the first set temperature.If the detected temperature does not exceed the first set temperature, printing of the line is executed, and the first set temperature is also set. When the temperature exceeds the second set temperature, a second determination is made as to whether or not the temperature detected by the temperature sensor exceeds a second set temperature set higher than the first set temperature, and the temperature does not exceed the second set temperature. Control means for executing printing of the line by interval printing provided with a predetermined non-printing time, and stopping printing when the temperature exceeds a second set temperature and returning to the first judgment. did.

[0005]

When the temperature detected by the temperature sensor exceeds the first set temperature and does not reach the second set temperature, the printing of the line is executed by interval printing with a predetermined non-printing time. The time required for the temperature rising gradient to decrease and the temperature to reach the second set temperature becomes longer, and even when the temperature reaches the second set temperature and printing stops even in a short time, the temperature rise gradient is small. The printing is resumed by lowering the temperature below the second set temperature, and the printing stop time is reduced.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the illustrated embodiments. FIG. 1 shows an embodiment of an impact printer according to the present invention, in which an impact head 1 is arranged in an impact printer 100, and the impact head 1 detects a plurality of coils 2 and the temperature of the coils 2. The thermistor 3 is provided. An A / D converter-4 for converting a voltage change of the thermistor 3 into a digital amount;
A CPU 5 for controlling a printing operation of the impact printer,
A print buffer 6 for storing print data, and a coil drive circuit 7 for supplying a current to the coil 2 of the impact head 1
And a CR motor for driving the CR motor and the LF motor, respectively.
Motor drive circuit 8, LF motor drive circuit 9, I / O 10,
A current flows from the power supply voltage Vcc to the thermistor 3 via the resistor 13, and the temperature Th of the coil 2 of the impact head 1 is detected from the voltage change due to the resistance change of the thermistor 3.

[0007] The operation of the apparatus thus constructed will be described with reference to the flowchart shown in FIG. Prior to one-line printing, first, a first determination is made as to whether or not the detected temperature Th of the thermistor 3 is higher than the first set temperature T1 (step A). If the temperature is not exceeded, one-line printing of the line is executed (step b). If the temperature is exceeded, it is determined whether the temperature detected by the thermistor 3 exceeds the second set temperature T2 (T2> T1). Make a second judgment (step c),
If not exceeded, an interface with a predetermined non-printing time
Execute the printing of the line by the global printing (step
D) If it exceeds, stop printing (step
E), returning to the first determination in step (a).

Here, the first set temperature T is a limit temperature at which continuous use is possible, and the second set temperature T2 is a limit temperature at which interval printing is possible. Each set temperature is obtained by an experiment. In this embodiment, T2 = 100
° C and T1 = 95 ° C. The non-printing time during interval printing is set to 0.1 second.

Referring to FIG. 3, a change in the detected temperature Th of the coil 2 by the thermistor 3 of the present embodiment will be described in comparison with a conventional example. The set temperature for stopping printing in the conventional example is T2 = 100 ° C., which is the same as in the present embodiment. In the first and second determinations (Steps I and C), a predetermined non-printing time is provided when the detected temperature Th exceeds the first set temperature of 95 ° C. and does not exceed the second set temperature of 100 ° C. Inter
The printing of the line is executed by the global printing. By this operation, from the time when the detected temperature Th of the coil 2 exceeds 95 ° C.,
Since the load is reduced, the time required for the temperature rising gradient to decrease and reach the second set temperature (100 ° C.) is longer than in the conventional example. As a result, the time from the start of printing to the stop of printing is longer than in the conventional example, and the user does not feel uncomfortable.

The gradient of the temperature rise after the temperature exceeds the first set temperature (95 ° C.) is small for interval printing, and after the temperature reaches the second set temperature (100 ° C.) and the printing is stopped, The amount of temperature overshoot in the vicinity of the thermistor 3 due to thermal inertia is also smaller than in the conventional example. As a result, the time (t1) during which printing is stopped is shorter than the time (t2) in the conventional example, and there is no data communication error with the host computer. Is not mistaken for failure.

[0011]

As described above, according to the present invention, when the temperature detected by the temperature sensor exceeds the first set temperature and does not reach the second set temperature, an interface having a predetermined non-printing time is provided. -Since the printing of the line is executed by the valley printing, the temperature rising gradient becomes small and the time required to reach the second set temperature becomes long, and the temperature rising gradient is small so that the temperature reaches the second set temperature. After the printing is stopped, the temperature becomes lower than the second set temperature in a short time, so that the time during which the printing is stopped can be shortened, and the inconvenience of causing the user to mistake as a failure can be prevented.

[Brief description of the drawings]

FIG. 1A is a block diagram showing the configuration of an impact printer according to an embodiment of the present invention, and FIG. 1B is a flowchart showing the operation thereof.

FIG. 2 is a temperature rise diagram showing a coil temperature rise of an impact head of the impact printer according to the embodiment of the present invention.

FIG. 3 is a diagram showing a change in a detected temperature Th of a coil 2 detected by a thermistor 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Impact head 2 Coil 3 Thermistor 4 A / D converter 5 CPU 6 Print buffer 7 Coil drive circuit 8 CR motor drive circuit 9 LF motor drive circuit 10 I / O 11 I / O 12 I / O 13 resistance 100 impact printer

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B41J 2/30

Claims (1)

(57) [Claims] 1. An impact head for driving an armature by an electromagnet and performing printing by a printing wire engaged with a tip of the armature, a temperature sensor for detecting a temperature of the impact head, and a temperature detected by the temperature sensor. and control means for controlling the printing operation in accordance with, the impact printers for printing line by line, before start of printing one line, said temperature sensor - one of the detected temperature exceeds the first set temperature performs first determination whether or not the temperature sensor when the time does not exceed the first setting temperature to perform printing of the line, also that exceeds the first preset temperature - the detected temperature is first Set higher than one set temperature
Perform a second set temperature second determination of whether or not beyond, which is constant, when it does not exceed the second set temperature interface provided a predetermined non-printing time - the printing of the line by Bal printing And a control means for stopping printing when the temperature exceeds the second set temperature and returning to the first determination.