JPS6241813Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper detection device used in a printing device such as a line printer.

Such paper detection devices include a device that detects the presence or absence of paper, a device that detects the end of paper, and a device that detects the running of paper, etc. Detection means include a micro switch, a transmission type, and a reflection type optical device. There is a detection means, etc., but in order to ensure reliable detection even if the paper width changes, the detection means is engaged with the paper feed hole and works in conjunction with the tractor that feeds the paper. Generally, it is possible to move in the width direction.

However, the outer end of the holder that holds the detection means inside the tractor is generally installed at a predetermined distance from the edge of the paper so as not to come into contact with the paper, that is, it extends outside the tractor. Therefore, the width of the printing paper that can be used is limited to the width up to the point where the outer end of the holder hits the frame, and the margin between the edge of the paper and the first digit printing position or the last digit printing position is small.
There were some inconveniences such as limited printing specifications. That is, it becomes impossible to arbitrarily set the first digit printing position or the last digit printing position, and printing specifications are limited.

An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to prevent the deterioration of printing function due to the interlocking of the tractor and the detection means.

The present invention focuses on the fact that if the outer end of the holding body is prevented from moving by the frame, it becomes impossible to align the print position on the paper with the printing hammer, and the paper is moved to the left or to the left in a limited space. The printer is designed to move as far to the right as possible to secure the printing position, thereby preventing the printing function from deteriorating.

That is, the holding body can automatically shift the tractor by the compression of the spring and its restoring force.

The figure shows one embodiment of the present invention, and although an example is shown in which the detection means is installed on the left side of the paper 1, it goes without saying that the same effect can be obtained by installing it on the right side. A pair of upper and lower tractors 2 which engage with the feed holes along both side edges of the paper 1 to feed the paper 1 are attached to a tractor shaft 3 so as to be movable in the axial direction. The tractor shaft 3 is supported by frames 4 provided on both sides of the path along which the paper 1 travels.
A printing mechanism consisting of, for example, a type conveyor and a printing hammer is installed between the upper and lower tractors 2, but this is not relevant to the gist of the present invention and is therefore omitted.

A holder 5 that holds the detection means (not shown) at a position inside the tractor 2 and has an outer end extending outside the tractor 2 has a spring 6 attached to the outer end, and a spring 6 attached to the spring 6. A recess 8 extending in the width direction of the pressing body 7 and the paper 1 is provided. The upper end of the inner end of the pressing body 7 is attached to the lower end of the interlocking plate 9, which is attached to the lower tractor 2.

When the tractor 2 is moved along the tractor shaft 3 in accordance with the width of the paper 1 to be used, the holding plate 5 is also moved at the same time via the interlocking plate 9, the pressing body 7, and the spring 6. That is, the detection means also moves in the width direction of the paper 12 in accordance with the width of the paper 1. The left tractor 2 is moved to the left so that the outer end of the holder 5 hits the frame 4. When the tractor 2 is further moved from this state, the interlocking plate 9 and the pressing body 7 move while compressing the spring 6, so that the outer end of the interlocking plate 9 moves into the recess 8.
Tractor 2 can be moved until it hits the outer end of. That is, by compressing the spring 6, it is possible to use a sheet 1 that is wide enough to allow the interlocking plate 9 to hit the outer end of the recess 8, and the first digit can be printed at any position inside the sheet 1. Can be set.

As described above, according to the present invention, even if the holder hits the frame, the tractor can still be moved, so it is possible to use a large width of printing paper, and it is possible to move the tractor to the left or right side of the paper. The margin becomes larger and there is no fear that printing specifications will be limited.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the paper detecting device of the present invention, and FIGS. 2 and 3 are schematic diagrams for explaining the operation of the paper detecting device of the present invention. In the figure, 1 is paper, 2 is a tractor, 3 is a tractor shaft, 4 is a frame, 5 is a holding body, 6 is a spring, 7 is a pressing body,
8 is a recess, and 9 is an interlocking plate.

Claims (1)

[Scope of utility model registration request] A tractor is movable along a tractor shaft supported by a frame provided on both sides of the paper running path and engages with a paper feed hole to feed the paper, and a tractor is provided near the tractor to feed the paper. a holder that holds the detection means at a position inside the tractor, extends outside the tractor, and has an outer end located inside the frame; one end is attached to the tractor; A paper detecting device comprising an interlocking plate attached via a spring to an outer end of a holder having a predetermined interval therebetween.