JPS5814712B2 - Timing signal skew compensation circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a timing signal skew compensation circuit for compensating for a deviation between two clocks generated from a mechanism in a paper card punching and printing device.

When punching and printing on paper cards are performed using the same device, the entire feeding path is constructed as shown in FIG.

The apparatus and operation of FIG. 1 will be explained in accordance with the flow of card processing.

First, the cards 2 stored in the hopper 1 are fed one by one by the picker 3 driven by timing from a main clock (MC) counter.

The card 2, which is fed at a constant speed by rollers 4 and 5, is stopped by a brake plate 13 when its rear end leaves the slot 5.

At this time, the pinch rollers 6 and 7 are in an off state.

The aligner 14 is driven and the card 2 is positioned.

The rollers 4 to 7, 11.12 and the eccentric shaft 15 are connected to one motor (hereinafter referred to as a main motor) by a synchronous transmission mechanism such as a toothed belt, and are constantly rotating.

A code plate 16 is attached to the eccentric shaft 15, and a main clock (
MC), and a sub-clock (
SC) is taken out, and the state of the device is represented by these two clocks.

The rollers 6 and 7 are driven through Geneva gears and perform intermittent feeding once per rotation of the eccentric shaft.

Furthermore, after the punch 17 descends and the punch blade hits the paper card 2 and punches it out, the intermittent feed stop time arrives during the time until the punch 17 rises and the blade comes out from the paper card 2. It is synchronized like so.

Further, the rollers 6' and 7' are pinch rollers, which are biased so as to restrain the paper card 2 when the paper card 2 is intermittently fed by an electromagnet or the like.

The jaws 8, 9, 10 are driven by DC motors.

The roller 8' serves as a pinch roller and is energized by an electromagnet or the like at the beginning of card feeding.

That is, as soon as roller 7' is turned off, roller 8 is turned off.
' is turned on and feeding by the DC motor is started.

The sensor 18 is installed for the purpose of creating the timing to start counting the clock from the code plate 21 attached to the DC motor output shaft in order to stop the card 2 at a predetermined position, and detects the front end of the card 2. .

Therefore, when the front end of the card passes the sensor 18, the clock from the code plate 21 is counted and the card 2 is stopped at a predetermined position.

The wire dot print head 20 includes a dot print head 20 that can reciprocate in a direction perpendicular to the plane of the page of FIG.
Powered by the main motor, a pair of electromagnetic clutches
Perform reciprocating motion using the brake.

A clutch that drives the carriage is turned on at a certain timing, and printing is performed in accordance with the printing position corresponding to the position of the carriage, and is ejected toward the platen 19.

When the desired number of lines have been printed, the DC motor is restarted and the card 2 is fed.

The processed cards 2 are stored in the stacker 23 or 24 by rotating the rollers 11 and 12 while moving the selection valve 22 up and down.

As described above, in the apparatus shown in FIG. 1, all operations other than the print carriage operation and the DC motor feeding operation are completely synchronously controlled using the main clock MCO as a reference.

In FIG. 1, one code plate 16 is shown as a mechanism for generating the main clock MC and sub-clock SC, but in reality, each code plate 16' is separate.
, 16'', and after one spine is cut on the circumference of each disk, they are connected to each other via a set screw and aligned so that the grooves of the two disks coincide.

The main clock MC is assumed to be CL1, and the sub clock SC is assumed to be CL2.

For example, the adjustment is made so that when 10 clocks CL2 are output, one clock C1 is output.

When the card 2 starts with the clock LC1 at the home position, the position of the card 2 on the feeding path can be calculated by counting the number of clocks of the clock LC2.

Therefore, both clocks CL1 and CL2 must occur at the same time, but since the positions of the disks 16' and 16'' are manually adjusted, it is extremely difficult to generate them at the same time.
Either clock CL1 or CL2 will be output first.

Normally, of the two clocks CLI and CL2, a circuit is provided that sets the time width by using CL1 as a trigger and counting CL2.
If CL2 does not occur at the same time, there will be a difference in time width.

That is, as shown in FIG. 2a and b, the clock CL1
, CL2 occur at the same time, the clock CLI
When the clock CL2 is counted from 1 to 4 using the clock CL2 as a trigger, the output of the counter CTR becomes a specified time width T as shown in FIG. 2C.

However, depending on the adjustment method of the mechanism, clock CL2 may occur later than clock CLI as shown in FIGS. 3a and 3b, and since counter CTR counts the first clock CL2, As shown in FIG. C, the counter output has a time width T', which is shorter than the specified time width T.

For example, the specified time width T is 4 ms, but due to manual adjustment errors, it can deviate by up to about 150 μs.
) L or not, time width T of counter CTFt output
' is approximately 1 mS shorter than the specified time width T.

The synchronous control system excites the picker 3 at 4 mS, for example, and
Stop the card in mS, and pinch roller 6 in 15mS.
', therefore, if each output width of the counter CTR is short, accurate position control becomes impossible.

The purpose of the present invention is to solve this problem by bringing the counter output time width closer to the specified value even if the main clock and sub clock code plates are misaligned or manually adjusted. Due to card feeding,
The objective is to control operations such as drilling at the correct position.

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

FIG. 4 is an operation time chart, and FIG. 5 is a block diagram of a skew compensation circuit for the main clock signal and sub-clock signal.

As shown in FIG. 5, the present invention provides a second counter circuit CTR2 for a first counter circuit CTRI which counts a sub clock by using a main clock as a trigger.
and gate circuit AND, and clock CL.
The output width T of the counter CTR1 is brought close to the specified value T by inhibiting the clocks CT, 2 which are output within a time t from 1 to 2.

That is, first, in counter CTR2, clock CL1
is used as the trigger input TRG to count the internal clock CLO of the program, etc.

Since the interval of the internal clock CLO is, for example, 80 nS, the output width t of the counter CTR2 is 150 μs when the internal clock CLO is counted 1875 times.

Next, the output of counter CTR2 is ANDed
, clock CL2 is inhibited only for the time width t, so clock CL2 after 150 μs
is added to the counter CTR1.

The counter CTRI uses the trigger input TR of the cross clock CL1.
G and counts the clock CL2, but the clock CI. , 2, the time T'' of the output OUT of the counter CTR1 is almost the same as the specified time T, and the error is 150
It is within μs.

That is, as shown in FIG. 4a and b, the clock C L
If clock CL2 occurs slightly later than clock CL1, the delay time is usually within 150 μs, so the first evening clock C
L2 is inhibited and counter CTR is clocked C
L2 is counted from 1 to 4 to provide an output with a time width T shown in FIG. 4d.

Therefore, T in this case is 150 times smaller than the specified time width T.
Although it becomes longer by less than μs, control can be performed at a substantially normal position.

Moreover, contrary to the cases shown in FIGS. 4a and 4b, if clock CL2 occurs slightly earlier than clock CL1, no clock CL2 is inhibited and the counter CTR
is the specified time width T by counting clock CL2 from 1 to 4.
It provides an output with a shorter time width of 150 μs or less.

In this case as well, synchronous control is performed at the normal tenon position.

Outputs having various time widths are taken out from the counter CTR1, and the cards are controlled at respective timings.

Generally, the timing after several revolutions is taken from the code plate 16'' of the clock CL2, but basically it is the same as the timing during one revolution.

As explained above, according to the present invention, even if the two code plates that generate the clock are misaligned,
Since the output time width of the counter can be made almost the same as the specified value, the skew of the timing signal (emitter signal) is effectively guaranteed, and complete synchronous control using the clock from the code board is possible.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the mechanical part of the paper card punch printing device, Fig. 2 a, b, c and Fig. 3 a, b, c are time charts of conventional timing signal setting operations, Fig. 4 a, b,
FIG. 5 is a block diagram of a timing signal skew guarantee circuit showing an embodiment of the present invention. CTR1, 2: Counter, AND: Gate circuit, CL
1, 2: Main sub clock, TRG: Trigger input, OUT: Timing output, CLO: Electrical clock, T'': Guaranteed good timing signal width.

Claims (1)

[Claims] 1. In a circuit that has two code plates providing a main clock and a sub clock, and sets a timing signal by counting the sub clock using the main clock as a trigger with a first counter, a second counter which generates an output while a separately provided internal clock is counted by a predetermined number using the main clock as a trigger; and a gate which receives a sub clock and whose output is inhibited by the output of the second counter. A skew compensation circuit for a timing signal, wherein the first counter is triggered by a main clock to count a fixed number of clocks output from the gate to generate the timing signal.