JPH0616197B2 - Image forming device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, and in particular, it counts pulses of a pulse generator using a microcomputer and executes sequence control by the counted value. The present invention relates to an image forming apparatus.

(Prior Art) A conventional sequence control method for a copying machine is represented by a flowchart shown in FIG.

This is because a predetermined pulse count value for turning each load (“A”, “B” ...) On and off and a pulse count value to be counted up are compared and judged, and if they match. This is a control method in which the corresponding load is controlled and the next predetermined pulse count value and the counted pulse count value are compared and judged.

That is, if the pulse is 0, the load “A” is turned on, when the pulse becomes 1, the load “B” is turned on, when the pulse becomes 3, the load “A” is turned off, and the next step is performed. move on.

Such a sequence control method has drawbacks such as a long program execution time, a variation in execution time depending on load operating conditions, and a complicated timing change.

(Object) The present invention has been made in view of such drawbacks of the conventional example, and it is possible to achieve a simple configuration of a sequence control program, a reduction in the number of steps, a faster execution time, and an easier timing change. At the same time, it is an object to provide an image forming apparatus that can be standardized.

(Structure) Therefore, the present invention is a control table in which a start address of a subroutine of a control procedure of each load of an image forming apparatus controlled by a microcomputer and a positive integer are paired and arranged in order of the size of the positive integer. A read-only storage element (ROM) storing the value, a count value counted by the pulse counting means and the positive integer recorded in the control table are compared, and the designated position of the control table is determined according to the comparison result. Sequentially, and at least during the period from the start of the reading operation of the first original to the discharge of the recording paper on which the image of the original is formed, the start of the subsequent copying operation of the original. The microcomputer has as many pointers as the number of times, and the microcomputer has a sub-address designated by the start address of the single control table pointed by each pointer. The control is performed in parallel for each bluetin according to the program of the subroutine.

An embodiment of the present invention will be described below with reference to the drawings.

First, the sequence control table will be described. As shown in FIG. 1, this table 1 is constructed on the ROM with a pair of positive integers (0, 1, 3, 5, ...) Compared with the pulse count value and the start address of the execution subroutine. Further, a pointer indicating the execution position of the table 1 and a pulse counter 4 for counting the pulses of the pulse generator are provided on the RAM.

The table of FIG. 1 is created by using a part of the time chart of FIG. 2 as a model. The outline of the operation is as follows: (1) When the copy operation is started by pressing the print button, the pointer 2 is set to the head of the table, that is, the position of "A",
The pulse counter is initialized to 0 (initial value “O” setting 5).

(2) The pulse count value on the table 1 pointed to by the pointer 2 is compared with the pulse count value counted by the pulse counter 4 for counting the number of pulses generated from the pulse generator 3. Pulse count value ≧ on the table When the condition of (a) is satisfied, the subsequent subroutine on Table 1 is executed,
The pointer 2 is moved to the position of the next count value. Actually, since the head address of the subroutine is described in the table 1, an indirect jump will be performed.

Pulse counter <Count value on the table ... (b),
The pointer remains at that position, and the following subroutine is not executed.

The above operation will be described with reference to FIG. 1. Since the pointer 2 is set to the position "A" and the pulse counter 4 is initialized to 0 at the same time, the condition of the expression (a) is satisfied, and The output load "1" N is executed and the pointer is moved to the position "C". At this position, the condition of Eq.

Next, when the pulse from the pulse generator 3 is detected, the pulse counter 4 becomes "1", and at this time, the equation (a) is satisfied and the output load "2" N of "D" is executed. The pointer 2 is moved to the position of "E". The same is repeated thereafter.

Normally, the copying apparatus does not have to control only one sheet of transfer paper at the same time in the continuous copying operation.
That is, for example, when a certain transfer paper starts feeding, the transfer paper sent before that is in the process of image transfer, and the transfer paper in front of it is in the process of being fixed. Always. This cannot be achieved with the ideas described above.

The control method in such a case will be briefly described with reference to FIG. The time chart is shown in FIG.

(1) When the copy operation is started by pressing the print button, the pointer "1" is set to the head of the table and the pulse counter "1" is initialized to 0.

(2) Pulse counter “1” ≧ subsequent subroutine is executed under the condition of the count value on the table indicated by the pointer “1”.

(3) The operation of (2) is repeated until the pulse counter “1” = 10.

(4) When the pulse counter “1” = 10, the copy operation for the second sheet starts. Therefore, the contents of the pointer "1" and the pulse counter "1" that have been used so far are transferred to the pointer "2" and the pulse counter "2" respectively, and then the first copy is the pointer "2". to manage. On the other hand, the above operation (1) is performed for the second copy, and the management of the second copy is executed with the pointer "1".

(5) When the counter “1” = 10 again, the next copy operation starts. This clock counter "2" consists of twenty.

Pointer "2", pulse counter "2" to pointer "3", pulse counter "3", pointer "1", pulse counter "1" to pointer "2", pulse counter "2" After that, the operation of (1) is performed. From this point on, the three sets of pointer pulse counters are managing separate copies in parallel.

(6) After that, the processing described in (5) above is executed every time the counter “1” = 10. In short, the pointer "1" has a pulse count value of 0 to 10, and the pointer "2" has a pulse count value of 10 to 2.
The pulse count value 20 and thereafter are always managed by 0 and the pointer “3”.

The required number of pointers and pulse counters can be calculated from the time chart shown in FIG. That is, it is determined by how many times the number of pulses required for the repeat operation completes the entire copying process. In the case of FIG. 4, the number of pulses required for the repeat operation =
It can be seen that 10 sets and all copying steps = 21, and 3 sets are required. 5 and 6 are flowcharts showing the control operation described above.

The sequence control main routine is incorporated as part of a subroutine that divides and executes each function of the system. The pulse counting routine is usually executed by a hardware interrupt of the pulse generator.

Although not shown, apart from FIG. 6, there are initial settings of the pointer “1” and the pulse counter “1” when the print button is pressed.

(Effects) The present invention is as described above, and according to the present invention, the microcomputer executes the program of the subroutine for each subroutine designated by the head address of the single control table designated by each pointer. Since it is controlled in parallel according to the above, the number of steps in sequence control is small and the program configuration is simple, so the processing time of the program routine is short,
Moreover, the processing time can be made uniform, and further,
When changing the control timing of each load, only the control table needs to be changed, so that the operation of changing the control timing of each load can be performed quickly and easily.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing the relationship between the sequence control table and the pointer according to the first embodiment, FIG. 2 is its timing chart, and FIG. 3 is a relationship between the sequence control table and the pointer according to the second embodiment. FIG. 4 is a timing chart thereof, FIGS. 5 and 6 are flowcharts of a main routine and a subroutine thereof, and FIG. 7 is a flowchart of a conventional system. 1 ... table, 2 ... pointer.

Claims (1)

[Claims] 1. A pulse generating means for generating a pulse signal,
An image forming apparatus comprising: a pulse counting means for counting pulse signals generated by the pulse generating means; and a microcomputer for performing sequence control based on the count value counted by the pulse counting means, wherein the microcomputer controls the microcomputer. A read-only storage element (ROM) that stores a control table in which a start address of a subroutine of a control procedure of each load of the image forming apparatus and a positive integer are paired and arranged in order of the size of the positive integer; By comparing the count value counted by the pulse counting means with the positive integer recorded in the control table, the designated position of the control table is sequentially moved according to the comparison result,
At least during the period from the start of the reading operation of the first document to the ejection of the recording sheet on which the image of the document is formed,
The microcomputer has as many pointers as the number of start times of the subsequent copying operation of the manuscript which is subsequently started, and the microcomputer is designated by the leading address of the single control table designated by each pointer. An image forming apparatus, wherein each of the subroutines is controlled in parallel according to a program of the subroutine.