JPH02255361A - Printer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a printing device in which a print head is mounted on a carriage and prints while the carriage is moved.

BACKGROUND OF THE INVENTION In recent years, printing apparatuses have been required to have high printing quality, and along with this, there has been a demand for carriages with high positional accuracy.

A conventional printing device will be described below.

FIG. 3 is a perspective view of a conventional printing device, in which 1 is a print head, 2 is a platen that supports paper (not shown) wound around it, and 3 is a carriage on which the print head 1 is mounted. , 4 is a carriage shaft that supports the carriage 3 so as to be slidable along the platen 2; 5 is a timing belt attached to the carriage 3; 6 is an encoder disk around which the timing belt 5 is wound and has a plurality of slits formed therein; Reference numeral 7 indicates a photo interlayer, and reference numeral 8 indicates a stepping motor that rotates the encoder disk 5. A stepping motor 8 is used to drive the carriage 3, which allows easy position control because the number of drive pulses matches the rotation angle. Further, the encoder disk 5 is provided to detect a state in which rotation of the stepping motor 8 is prevented for some reason.

The operation of the printing apparatus configured as described above at the time of overload will be described below.

Overload is a situation in which the movement of the carriage 3 is prevented during a printing operation, and the actual position of the carriage 3 does not match the position calculation of the computer (not shown in the figure) that controls its movement. In this case, the carriage 3 returns to a position beyond the predetermined stop position.

In the conventional printing device, if the carriage 3 is prevented from moving for some reason during its movement, the rotation of the encoder disk 6 is stopped and the signal from the photointerlab tough is stopped. This causes the computer to detect that the carriage 3 has stopped. After this,
The computer detects the stoppage and stops printing to prevent abnormal printing.

Problems to be Solved by the Invention However, the above-mentioned conventional configuration has a problem in that it uses a photointerlab turf and is expensive.

Means for Solving the Problems The present invention provides a home sensor for detecting the presence or absence of a carriage between the maximum movement range of the carriage and the movement range during printing, and detecting means for detecting the state of the home sensor when the carriage returns. It is equipped with the following.

Effect: With the above configuration, when the carriage returns beyond the range of movement during printing, the home sensor detects this state and determines that it is overloaded.

Embodiment FIG. 1 is a perspective view of a printing apparatus in an embodiment of the present invention, in which 1 is a print head, 2 is a platen, 3 is a carriage, 4 is a carriage shaft, 5 is a timing belt, and 8
is a stepping motor, and these have the same configuration as the conventional example. A leaf switch 9 is provided within the maximum movement range of the carriage 3 and outside the movement range of the carriage 3 during printing, and detects whether the carriage 3 is at that position.

FIG. 2 is a block diagram of the printing device of this embodiment.
11 is a control circuit that controls the print head 1 and carriage motor 8, and 11 is a detection circuit that detects the connection state of the leaf switch 9 when the carriage 3 returns to the leaf switch 9 side of the printing range after reciprocal printing or unidirectional printing. It is a circuit.

In the printing device of this embodiment configured as above,
The operation during overload will be explained.

First, if the movement of the carriage 3 is prevented for some reason during its movement, the control circuit 10 operates a counter (not shown in the figure) that counts a numerical value corresponding to the position of the carriage 3, even though the carriage 3 is stopped. (omitted) is incremented. After this, in the return process of the carriage 3, the return operation of the carriage 3 and the start of subtraction of the counter are performed at the same time, but the initial value of the counter before subtraction is the point at which the carriage 3 has actually stopped from the return position of the carriage 3. Since the value is larger than the value corresponding to the position where the carriage 3 was moved, the carriage 3 returns beyond the normal movement range during printing. At this time, the carriage 3 connects the leaf switch 9, which is within the maximum movement range of the carriage 3 and is provided outside the movement range of the carriage 3 during printing. The detection circuit 11 detects the state of the leaf switch 9 at the end of the reciprocal printing operation. At this time, the leaf switch 9 is in the connected state, so
It is determined that there is an overload, and the control circuit 10 interrupts printing.

According to this embodiment, the leaf switch is used instead of an encoder disk and a photocoupler as in the past, resulting in an inexpensive configuration, and the position of the leaf switch is outside the normal movement range during printing. Because of this, the leaf switch does not operate as long as the printing operation is performed normally, and only operates when the above occurs, so it is possible to use a leaf switch with a short lifespan, resulting in a cheaper configuration. I can do it.

Effects of the Invention The present invention includes a home sensor that detects the presence or absence of the carriage between the maximum movement range of the carriage and the movement range during printing, and a detection means that detects the state of the home sensor when the carriage returns. When the carriage returns beyond the printing range, the home sensor detects this condition and determines that it is overloaded.
A photo interleader and its detection circuit are not required, and overload can be detected at a low cost.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a printing device in an embodiment of the present invention;
FIG. 2 is a block diagram of the same, and FIG. 3 is a perspective view of the conventional printing device. DESCRIPTION OF SYMBOLS 1... Print head, 2... Platen, 3... Carriage, 4... Carriage shaft, 5... Timing belt, 8... Stepping motor, 9...
Leaf switch, 10...control circuit, 11...detection circuit. Name of agent: Patent attorney Shigetaka Awano (1 person) Figure 2 Figure 1 Print head Platen carriage Head carriage shaft Timing belt Steering motor Nof switch Section 3 Printing Rad Platen carriage Carriage shaft timing Belt encoder disc photo interlab testing motor

Claims (1)

[Claims] a printing means, a carriage on which the printing means is mounted, a support means for movably supporting the carriage, a stepping motor for driving the carriage, and a space between the maximum movement range of the carriage and the movement range during printing. A printing device comprising a home sensor for detecting the presence or absence of a carriage, and a detection means for detecting the state of the home sensor when the carriage returns.