JPS6348720B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printer tractor moving device that detects the position and size of paper initially set on a tractor and moves the tractor to a predetermined position.

When a printer prints output on paper, the position at which the paper is set may be determined for each paper size. In this case, in conventional printers, the paper is set at the printing position as follows. That is, the operator moves the tractors on the left and right as appropriate to hook the holes provided on both sides of the paper onto the claws of the tractor, and then fixes the tractor to the shaft. Next, the operator operates the printer at the position where the paper is set to print on the paper. This is to see how much "deviation" there is between the position of the set paper and the print position determined for each paper size. The operator moves the tractor by the amount of this "shift", fixes it, operates the printer again, and checks whether the paper is in the printing position. When the operator confirms that the paper is in the printing position, he starts printing, and on the other hand, when the paper is not in the printing position, he repeats the above procedure again.

As described above, with conventional printers, it takes considerable time for the operator to align the paper to the printing position, and since this is done manually, it is difficult to align the paper to the printing position accurately. It was hot.

The present invention was developed in view of these circumstances, and its purpose is to detect the position and size of the paper initially set on the tractor, move the tractor by the amount of "shift", and print on the set paper. It is an object of the present invention to provide a tractor moving device for a printer that can be adjusted to the desired position.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

The illustrated tractor 1 is for feeding paper, and this tractor 1 has a paper presser 2 on the top.
is attached, and a sprocket is built in underneath. The paper presser foot 2 is designed to undulate,
The sprocket is adapted to receive rotational force from the paper feed shaft 3. Furthermore, as shown in the figure, a through hole 4 is formed in the direction perpendicular to the paper feeding direction, and a female threaded portion 5 is formed in the vertical direction of this through hole 4, and a knob 6 is screwed into this female threaded portion 5. has been done. The tip of this knob 6 is designed to protrude into the through hole 4. This knob 6 is also used to move the tractor 1 left and right in relation to a transfer section 7, which will be described below.

The transfer section 7 includes a shaft 8 that moves the tractor 1 left and right, and a drive section 9 that rotates the shaft 8. The shaft 8 has a screw groove 1.
0 is formed, and a pulley 11 is fixed to one end. This shaft 8 is fitted into the through hole 4 such that the tip of the knob 6 protruding into the above-mentioned through hole 4 engages with the screw groove 10, and is rotated at any two points (not shown). It is supported by, for example, a bearing so that it can move freely and not move in the thrust direction. Therefore, this shaft 8
When the tractor 1 is rotated, the tractor 1 is moved in the axial direction by the knob 6 engaged with the screw groove 10 since it is supported by the two shafts 3 and 8. The direction and amount of movement of the tractor 1 are determined by the inclination angle of the screw groove 10 formed in the shaft 8 and the rotation direction and rotation speed of the shaft 8. A drive unit 9 rotates the shaft 8. This drive section 9 is composed of a pulse motor 12, a pulley 13 fixed to the motor shaft, and a belt 14 wound around this pulley 13 and the above-mentioned pulley 11. This pulse motor 12 rotates in either direction by a predetermined number of rotations in accordance with a control signal to be described later. This is determined by the position and size of the paper 15 initially set on the tractor 1.

The sensor 16 is for detecting the position and size of the paper 15 described above, and consists of a switch 19 attached to the carriage 18. Although the switch 19 is not limited to this, it is in a conductive state when the contact portion 20 is on the platen 17, and is in a non-conductive state when it is on the paper 15. This can be done by forming the outer cover of the platen 17 from a conductive material and passing an electric current through the outer cover. Further, when a large number of copies are to be printed, the thickness of the paper can be used to make conduction and non-conduction possible using a micro switch. This switch 1
Reference numeral 9 indicates a platen 17 and paper 15 by moving a carriage 18 using a pulse motor (not shown).
conduction or non-conduction by moving it at a constant speed.

A control section (not shown) detects the position and size of the set paper by detecting the conduction state of the switch 19. That is, from the time the carriage 18 starts moving from the reference position until the switch 19 becomes conductive (until one end of the paper is detected).
The number of pulses applied to a pulse motor (not shown) that moves the carriage 18 is counted. By measuring in advance how far the carriage 18 moves with one pulse, the position where the paper is set can be determined from the counted number of pulses. Further, while the switch 19 is in the conductive state, the paper size can be similarly determined by counting the number of pulses applied to the pulse motor to move the carriage 18.
Based on the detected paper size, the control unit reads out the printing position of the paper of the detected size from a storage unit that stores determination means corresponding to each paper of each size in advance. The control section detects the "misalignment" between the read printing position and the position where the paper is set. The control section determines the rotational direction of the pulse motor 12 necessary to correct this "deviation" and calculates the number of driving steps of the pulse motor 12.
The control section supplies the pulse motor 12 with the number of pulse signals necessary to drive the pulse motor 12 in a predetermined rotational direction by the calculated number of steps as control signals. The pulse motor 12 that received this control signal
rotates in a predetermined direction by a predetermined number of steps to connect the motor 12, pulleys 11, 13, and belt 14.
The shaft 8 connected via the shaft 8 is rotated to move the tractor 1 by the amount of "shift". When this tractor 1 moves by the amount of "shift", the paper set on it is aligned with the printing position.

In the tractor moving device configured in this way,
When the operator raises and lowers the paper presser 2, sets the paper 15 on the tractor 1, and scans the carriage 18 once, the paper 15 can be automatically aligned to the printing position.

Moreover, this tractor moving device moves the tractor 1 by loosening the knob 6 screwed onto the tractor 1.
can be moved manually.

As explained above, according to the present invention, once the paper is set on the tractor and the carriage is scanned once, the paper is automatically aligned to the printing position. There is no need to repeat such troublesome steps.

Further, according to the present invention, the paper can be accurately aligned to the printing position because manual alignment is not required as in the conventional method.

In the above embodiment, a pulse motor is used in the transfer section, and the control section generates a pulse train signal to rotate the pulse motor in a predetermined direction a predetermined number of times to rotate the shaft. The shaft is not limited to this, and the shaft may be rotated using various known means such as a DC motor and a servo mechanism.

In addition, in the example, a switch is used as a sensor to detect the position and size of the set paper, but in the present invention, a phototransistor is used instead of the switch, and the difference in brightness between the platen and the paper is used. Electrical signals can also be obtained.

[Brief explanation of the drawing]

The figure is a perspective view showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Tractor, 2...Paper presser, 3...Paper feed shaft, 6...Knob, 7...Transfer unit, 8...
... Shaft, 9 ... Drive section, 10 ... Screw groove, 12 ... Pulse motor, 15 ... Paper, 16
...sensor, 17...platen, 18...carriage, 19...switch.

Claims (1)

[Claims] 1 a platen, a pair of tractors for conveying the set paper, and a pair of tractors for transporting the set paper so that the paper is placed at a predetermined position on the platen; a carriage equipped with a print head that is movable parallel to the platen; a paper detection means provided on the carriage for detecting the paper disposed on the platen; When moving the carriage from one end of the platen to the other end, the tractor moving means for moving the paper in the direction of paper size determining means for determining the paper size; and paper size determining means that determines the paper size, and a paper size determined in advance according to the paper arrangement position and the paper size based on the paper arrangement position and the paper size determined by the paper size determination means. a deviation amount calculation means for calculating an amount of deviation from a position where the paper should originally be placed on the platen; and a deviation amount calculation means for controlling the tractor moving means based on the deviation amount calculated by the deviation amount calculation means; A printer comprising a control means for moving a pair of tractors and moving the paper set on the pair of tractors to a position where the paper should originally be placed on the platen according to the size of the paper. Tractor moving device.