JPS6160788B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printer having a margin setting mechanism for defining a printing range.

Conventionally, in printers that scan the recording head to write information on the recording medium, some printers are equipped with a margin set mechanism, but such printers detect the position of the recording head and control the margin set, so it is extremely difficult to do so. This required an accurate detection mechanism.

The present invention has been made to eliminate these drawbacks, and provides a margin set mechanism that allows easy adjustment during assembly even when using low-precision parts, and that can accurately detect the head position. It is something.

Other objects of the present invention will become clear from the description of embodiments given below with reference to the drawings.

One embodiment will be described below with reference to the drawings.

FIG. 1 shows a perspective view of a printer according to the invention. In the figure, a head carriage 2 to which a print head 1 is attached is slidable along a slide shaft 3 and is connected to a pulse motor 7 via a wire 4, an idle pulley 5, and a drive pulley 6. As the pulse motor 7 rotates, the print head 1 moves along the slide shaft 3 to perform appropriate printing on the recording paper 8.

Furthermore, as margin setting means, left and right margin set carriages 11 and 12 to which left and right head position detectors 9 and 10 are attached are movable along a guide rail 13.
It is possible to fix every two digits by means of notches 14 provided at one-digit intervals d and click mechanisms (not shown) provided on the left and right margin set carriages 11 and 12.

Here, as the detection means for the left and right head position detectors 9 and 10, contact type switches such as a spring set switch, micro switch, reed switch, etc., and non-contact type switches such as a Hall element switch or a photocoupler can be considered.

Here, the operational relationship between the print head 1 and the head position detector will be described.

In FIG. 2, a contact shaft 1 that is slidable in the axial direction of a slide shaft 3 is mounted on a head carriage 2.
6 is provided.

Washers 18, 18' are fitted on both sides of a tensioning washer 17 fixed to the center of the contact shaft 16. The washers 18, 18' are movable in the axial direction of the contact shaft 16 independently of the contact shaft 16.

Further, coil springs 19, 19' are installed coaxially with the contact shaft 16, and washers 18, 1
8' is pressed against the stopper 20.

Now, the head carriage 2 is moving in the direction of arrow A, and the right end of the contact shaft 16 pushes the first leaf spring set 21 of the right head position detector 10, and the first leaf spring set 21 and the second leaf spring set 22 come into contact. Detects the position of the head. Here, it is necessary to select the elastic force of the coil spring 19' to be stronger than the elastic force of the first plate spring set 21 and weaker than the combined elastic force of the first plate spring set 21 and the second plate spring set 22.

Next, when the head carriage 2 moves further in the direction of arrow A to the designated digit, the right end of the contact shaft 16 is pushed in, so the position of the head can be detected without affecting the first and second leaf spring sets 21 and 22. will be maintained.

The above description has been made regarding the detection of the right head position, but the invention can be similarly applied to the detection of the left head position.

Further, the detection means can be applied not only to the leaf spring set switch but also to all contact type switches.

Note that a member for absorbing the contact impact may be provided on the detector.

In Fig. 1, a 4-phase (4-step) pulse motor is used as the pulse motor 7 for driving the head, and the printing head 1 is moved by one digit d by two-step rotation of the pulse motor 7. The diameter of the drive pulley 6 is selected.

Further, the guide rail 13 is provided with a notch 14 every two digits 2d, so that digits can be designated every two digits.

FIG. 2 is a diagram showing the principle of a four-phase pulse motor.
By energizing each phase φ1, φ2, φ3, and φ4 in sequence, the rotor 15 rotates in the forward direction, causing the drive pulley 6 coaxial with the rotor 15 to rotate, and the print head 1
This is a movement in the digit direction. Conversely, by sequentially energizing each phase as φ4, φ3, φ2, and φ1, the rotor 15 is reversed, and the carriage return of the print head 1 is performed. Therefore, by adjusting the rotational position of the pulse motor 7 and the position of the print head 1, the pulse motor 7 can be adjusted as shown in FIG.
There can be a one-to-one correspondence between the positions of the print head 1 and the phases of the print head 1.

Now, if the right head position detector 10 is set to an even number digit, the phase of the pulse motor 7 will always be φ3. Therefore, as shown in FIG. 4, the AND gate AG1 calculates the AND of the detection signal of the right head position detector 10 and the phase signal φ3 of the pulse motor 7, and outputs the carriage return signal to the printer control circuit (not shown). It is something to do. With this configuration, even if the right head position detector 10 outputs a detection signal a little before the specified digit (for example, at φ2), it will become a phase signal φ3, and the print head 1 will be in the normal position. A carriage return signal is obtained only when the carriage is moved to the position shown in FIG.

This relationship holds true for the left head position detector 9 as well.

Therefore, in this embodiment, even if there is some error in the detection position of the print head 1, digits can be detected accurately, and the detection means will not be damaged by the print head.

As described above, although the present invention is provided with the detection means at both the left and right ends of the movement area of the head carriage, it is possible to absorb the impact when the head carriage comes into contact with these detection means, and The present invention is extremely useful as it provides an inexpensive margin setting mechanism that does not require high component precision and is easy to assemble and adjust.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a printer having a margin setting mechanism according to an embodiment of the present invention. FIG. 2 is a detailed view of the printing head, and FIGS. 3a and 3b are diagrams illustrating the operation of the printing head and head position detector. FIG. 4 is an explanatory diagram showing the principle of a pulse motor. FIG. 5 is a diagram illustrating an embodiment of the present invention. FIG. 6 is a signal system diagram of one embodiment of the present invention. 1...Print head, 6...Drive pulley, 7...Pulse motor, 8...Recording paper, 9...Left head position detector, 10...Right head position detector, 11...Left margin set carriage, 12...Right margin set carriage, 13...guide rail, 15...rotor, 16...contact gear.

Claims (1)

[Claims] 1. A printer that records on a recording medium, comprising a recording head for recording on the recording medium, a head carriage that supports the recording head, and a head carriage that allows the recording head to reciprocate along the recording medium. a drive means for reciprocating the carriage; a first detection means for detecting the position of the head carriage, which is provided on the left end side of a movement area of the head carriage reciprocally moved by the drive means; a second detection means for detecting the position of the head carriage provided on the right end side of the area; a contact member provided therein; and first and second elastic members provided between the head carriage and the contact member along the contact member on the left and right sides of the fixing member fixed to the contact member. A printer comprising: shock absorbing means for absorbing a contact shock between the head carriage and the detecting means.