JPS5872484A - Generation of sending hole pulse of continuous slip - Google Patents

Abstract

PURPOSE:To lessen the disorder of the reference position for raising the accuracy of the stop position of slips by generating sending hole pulses when a predetermined value is reached according to specific pulse widths among adjacent sending hole signals for continuous slips. CONSTITUTION:A fixer is provided with a sending hole detector 9, a motor 12 to drive a heat roller and an encoder 13 attached to the motor 12. Since the running amount of paper is considered to be determined by the revolving number of the heating roller, the pulse width of the sending hole signal is investigated by counting encorder pulses contained in the sending hole signal. Also, the skew running of paper between the sending hole intervals is considered to be less and the pulse widths of the adjacent sending hole signals are considered nearly equal. Even when the pulse widths of the sending hole signals are varied by the skew running, the reference position can be kept constant if pulse is generated as hole pulse at the center position regardless of the speed of paper because the center position of the pulse is almost immovable.

Description

[Detailed description of the invention] The present invention relates to a method for generating Hall pulses.

FIG. 1 schematically shows a fixing device of a printer employing an electrophotographic method. Both sides of the folding perforation of paper 4! It is assumed that a certain range of the screen, for example, a range asmm from the perforation, is not printed, and this part is called a print-prohibited area. The toner (black powder book) adhering to the paper 4 is heated by the preheater 1,
When the printing that is fixed by the heat roller 2 and the backup roller 3 stops, the paper in the electric layer part also stops, but when it stops, only the print-prohibited area comes into contact with the heat roller so that the toner on the paper does not adhere to the heat roller. must be maintained. Assuming that the contact width between the heat roller and the puncture-up roller is 12 m, and the print-prohibited area is as mm on both sides of the perforation, the error in the perforation position when stopped is 5 cm or less. There must be.

Now, in order to detect the amount of paper fed out by the heat roller, a feed hole detector is provided in the fixing device at a portion where the paper passes through the holes. The hole diameter is 4 m.

l @ Figure 2 shows the feed hole detector, Figure 3 shows the detector output 20 (
large feed signal). When the feed hole passes through the detector part and the light from the light emitting diode 5 is not reflected by the shield 4, no current flows through the phototransistors 1 and 2, and to is 0. When paper exists, to becomes 1. Feed holes are drilled every 12.7 mm, and the amount of paper fed out from the sheet roller can be determined by counting the large feed signal. By the way, there are restrictions as mentioned above when stopping the paper, but in order to control the paper stop position in this way, a pulse is created at the trailing edge of the large feed signal (point A in Figure 6) (
The pulse created from the large sending signal is called a Hall pulse)
, in this case, refers to the pulse generated at A in Figure 3, and deceleration is started using the position where this pulse is generated as the reference position, so that the perforation stops at the center of the contact area between the heat roller and the backup roller. controlled. But in this case,
When the paper is skewed on the preheater, the width of the large feed signal changes and the position where the Hall pulse is generated is also shifted.

゛ Since the reference position will be incorrect, the stopping position of the perforation will also be shifted, and the reference position will be up to 2m due to skew.
I'm going to go crazy.

The object of the present invention is to generate a hole pulse at a nearly constant position (d) even when the number of sprocket holes changes due to skewing of the paper, thereby reducing deviations in the reference position and improving the paper stop position. ?# We are trying to improve our level.

The present invention focuses on the fact that the pulse widths of adjacent large feed signals are almost equal, and from this (yellow out JQ feed), a hole pulse is generated according to the pulse width of the feed hole one position before the large feed signal. The timing is determined.The center of the large feed signal does not move much regardless of the pulse width, that is, even when moving diagonally, so if a pulse is created near the center and this is used as a Hall pulse, the reference position is set to the oblique position. It remains almost constant regardless of the row.

A view of Figure 1 viewed from the direction of the arrow is shown in Figure 4\4.

In Fig. 4, 9 is a feed hole detector, 10 and 11 are gears, 12 is a motor that drives the heat roller, and 13 is an encoder attached to the motor.The number of pulses of the encoder is 240 per rotation of the motor shaft. Assume that the paper is fed out from the heat roller by approximately 518 mm per revolution of the motor shaft (an error occurs due to variations in the heat roller diameter, etc.).

Therefore, it is approximately 0.21 ffiI per encoder pulse. Since it is thought that the paper running condition is determined by the rotation sound of the heat roller, by counting the encoder pulses included in the large feed signal, we can find out that the pulse width of the large feed signal is 61! I can be seen. Furthermore, the interval between the feed holes is 12.7 mm, and there is little skewing of the paper during this interval, and the pulse widths of the large feed signals that make instant contact are considered to be almost equal. Even if the pulse width of the large feed signal changes due to skewing, the center position of the pulse remains almost constant, so if you create a pulse at the center position regardless of the paper speed and use this as the Hall pulse, the reference position will be skewed. It will remain constant regardless of the Now, in Fig. 6, P, 1 is the perforation hole number that has already been detected, and the number of encoder pulses counted in PO is no.
Individual. It is assumed that the Hall pulse pl is generated when encoder pulses are counted starting from the leading edge of the large signal P1 to be sent and N pulses are counted. It is assumed that the value of N is selected according to the value of no as shown in FIG. If the relationship between no and N is determined in this way, the error of the Hall pulse generation position from the center position of the large sending signal will be as shown in FIG. For example, if no:=15, N=7 and the error from the center position of the Hall pulse generation position is 0.5XO
121 (=-'0.105. For all nos, the maximum error amount from jft in front of the center of the Hall pulse generation position is 1.5X[121=[L315.

This is about -〇〇 compared to the conventional one.

Next, a specific circuit will be explained with reference to FIGS. 7 and 8.

In M7IA, 14 is a counter for counting encoder pulses, and 15 is a latch, which captures the output of the counter in response to signal a in FIG. 8 and temporarily stores it. 16
is a ROM (Read Only Memory), and according to Figure 5, the Nll') value for no is
1". 17 is a counter, and the signal C in Fig. 8 is
The power of the ROM is taken in by and subtracted by the encoder pulse. 18 is a zero pulse circuit, and when the counter is subtracted by the encoder pulse and becomes 0, it becomes 1.
generates several pulses (Hall pulses).

According to the present invention, even when the paper is skewed, the error in the position where the hole pulse is generated can be reduced, so that the paper stop position EFi4[ can be improved.

In the example, the value of N is divided into five stages, but if it is acceptable even if the error is historically large, it may be divided into six stages, for example, as shown in X-X in Fig. 5. In this case, the maximum error is [1
It becomes 63°1. Also, the number of pulses of the motor encoder is 1
It does not have to be 240 turns per rotation, but it may be selected so that the required 48 degrees can be obtained.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a fixing device, where 1 is a preheater, 2 is a heat roller, 3 is a backup roller, and 4 is paper. Figure 2 is a seven-character diagram of the sprocket hole detector. 5 is a light emitting diode, 6 is a phototransistor, 7 is a perforation hole, and 8 is a resistor. FIG. 3 is a time chart showing the relationship between the conventional detector output and the Hall pulse, and FIG. 4 is an arrow diagram of FIG.
12k motor, 13k encoder. Figure 5 shows n
FIG. 6 is a diagram showing the error from the ino-center position with respect to no. FIG. 7 is a block diagram showing an embodiment of the present invention. 16 is a ROM, +7 is a counter, and 18 is a zero pulse circuit. Figure 8 is the time chart for No. 1g used in Figure 7. Patent issued, name of acquaintance Hitachi Koki Co., Ltd. Saij map - f2 leap year 30 year 4 figure year 51 yen `i = 7 figure 8th hole l gurusu

Claims (1)

[Claims] In a device that has a motor that is the driving source for sending continuous slips and an encoder that detects the rotation angle of this motor, one 1÷6→Hall pulse ÷ corresponding to the feed hole drilled in the continuous slip is used. Regarding the method of generating , the numerical value N is determined corresponding to the pulse width of the signal that is generated earlier among the adjacent large feed signals, and the encoder pulse starts from the time when the later large feed signal starts to be generated. How to start counting.