JP2705244B2 - Waveform recording device - Google Patents

Description

The present invention relates to a waveform recording device (plotter) suitable for recording a waveform such as a chromatogram.

(B) Conventional technology In recent years, an ink jet head is used as a print head of a waveform recording device that records a waveform such as a chromatogram. This ink jet head records a waveform by ejecting minute ink droplets onto recording paper.

This type of waveform recording apparatus includes, in addition to an ink jet head, a pen motor for moving the ink jet in the recording paper width direction, and a chart motor for feeding the recording paper. A pulse motor is used for both the pen motor and the chart motor, and the rotation is controlled by inputting a pulse.
The ink jet head ejects ink droplets on recording paper when there is a pulse for a pen motor or a pulse for a chart motor.

(C) Problems to be Solved by the Invention In the above-described waveform recording apparatus, the resolution in the head moving direction (X axis) and the paper feeding direction (Y axis) are often different. This is because, in the case of a chromatogram, a clearer waveform can be drawn when the resolution of the Y axis corresponding to the time axis is higher than the resolution of the X axis corresponding to the voltage axis.

FIG. 5 is an enlarged view showing a waveform drawn on a recording sheet when the resolution of the Y axis is twice the resolution of the X axis. FIG. FIG. 5 (b) is based on an ink jet head.

In the drawing, the hatched area is a dot, and when the movement in the X-axis direction is small, the dots overlap. In the case of a thermal printhead, the area of the dots matches the area of the heating element, and even if the dots overlap,
It simply overlaps as shown in FIG.
The recorded waveform does not become thicker or thicker.

However, in the case of an ink jet head, although the diameter of the ink droplet itself is small, when the ink droplet adheres to the recording paper, it bleeds and spreads to a certain area. Generally, an aqueous ink is used, and its drying speed is low. Therefore, when dots move continuously at small intervals in the X-axis direction, bleeding becomes large as shown in FIG. 5 (b). . As shown in FIG. 6, there is a problem that the line of the recorded waveform becomes thick at a portion where the movement in the X-axis direction is reduced.

The present invention has been made in view of the above, and has as its object to provide a waveform recording apparatus that can draw a waveform with a uniform line when resolutions in two directions are different.

(D) Means and action for solving the problem In order to solve the above-mentioned problem, the waveform recording apparatus of the present invention comprises an inkjet head facing the recording paper, and two orthogonally interposed inkjet heads and the recording paper. A first pulse motor and a second pulse motor that perform relative movement in the directions, and when either the pulse of the first pulse motor or the pulse of the second pulse motor is input,
In the apparatus in which the inkjet head ejects ink droplets onto the recording paper, the inkjet head includes frequency dividing means for dividing a pulse of a pulse motor having a higher resolution in the two orthogonal directions and inputting the pulse to the inkjet head. It is characterized by having. Therefore, in the case where dots are continuous in the direction of higher resolution, dots are thinned out by dividing the pulse to prevent the dots from overlapping and greatly blurring.

(E) Embodiment One embodiment of the present invention will be described below with reference to FIGS.

FIG. 2 is a perspective view illustrating a mechanism of the waveform recording apparatus according to the embodiment.

Reference numeral 2 denotes a platen with a sprocket.
And has a function of feeding in the Y-axis (time axis) direction. The platen 2, the pulley 3 and is attached, between the pulley 5 attached to the rotation shaft of the chart motor M _C this pulley 3, belt 4 is stretched. By this belt 4 rotates the chart motor M _C is transmitted to the platen 2.

Reference numeral 7 denotes a bail shaft, which is supported by the platen 2 in parallel. A head carriage 8 is mounted on the bail shaft 7 so as to be slidable in an X-axis (voltage axis) direction orthogonal to the Y-axis. An ink jet head 9 is mounted on the head carriage 8, and the ink jet head 9 faces the recording paper C supported on the platen 2 at an appropriate interval.

The head carriage 8 is driven in the X-axis direction by a wire 10. Wire 10 is stretched between the pulleys 11 and 12, driven by Penmota M _P pulley 12 is mounted. Note that the pen motor M _P and the chart motor M
_C is a pulse motor, and the resolution in the Y-axis direction is twice the resolution in the X-axis direction.

FIG. 1 is a block diagram illustrating a circuit configuration of a waveform recording apparatus according to an embodiment. The waveform signal is input to the control circuit 14 via the input circuit 13. The control circuit 14, forward for Penmota M _P driven on the basis of the waveform signal pulse P _+, reverse pulse
P _- outputs a chart motor at fixed time intervals
Outputs a pulse P _C of M _C drive.

Forward pulse P _+, reverse pulse P _- is, Penmota drive circuit
Entered in 15. The pen motor drive circuit 15 outputs a forward rotation pulse.
When P ₊ is input, the ink jet head 9
As movement in the axial positive direction, the Penmota M _P is rotated one step, reverse rotation pulse P _- if is inputted, by one step reverse rotation of the Penmota M _P as the ink jet head 9 is moved in the X-axis negative direction .

On the other hand, the pulse P _C is input to the chart motor drive circuit 16. Chart motor driving circuit 16, so that a pulse P _C is inputted recording paper C is sent to the Y-axis positive direction, the chart motor M _C rotates one step.

Pulse P _C is also set terminal S of the flip-flop (FF) 17, and also to an input terminal of the AND circuit 18 is input.
The output Q of the flip-flop 17 is connected to the other input terminal of the AND circuit 18. The output of the AND circuit 18 is
Forward pulse P _+, reverse pulse P _- is connected to the OR circuit 19 with the output of the OR circuit 19 is inputted to the ink jet head 9, a reset terminal R of the flip-flop 17
Is input to

This example waveform recording device, forward pulse P _+, reverse pulse P _- when there is an output of the OR circuit 19 injects H (High), and the ink jet head 9 is an ink droplet onto a recording paper. However, this is the same as before.

A characteristic of the waveform recording apparatus of this embodiment is a case where there is no movement in the X-axis direction and dots continue in the Y-axis direction (see FIG. 3). When the dot d _n are attached, forward pulse P ₊
Is output from the control circuit 14, and the output of the OR circuit 19 becomes 'H' by the forward rotation pulse P ₊ ,
(See also FIG. 4). At this time, the reset terminal R of the flip-flop 17 also becomes “H”, and the output terminal Q becomes “H”.
Is reset to

Then, the only pulse P _C is outputted from the control circuit 14. When the pulse P _C is input to the terminal S of the flip-flop 17, the terminal Q is inverted to 'L' from the 'H'. And AND
The input terminals of the circuit 18 are 'H' and 'L', and the output is
It becomes 'L', and the output of the OR circuit 19 also becomes 'L'. There was a pulse P _C, is sent by one step the recording paper C, the ink jet head 9 is has to be positioned to d _{n + 1} shown by broken lines in the figure, the output of the OR circuit 19 'L' Therefore, no ink is ejected. Further, the flip-flop 17 is not reset, and the terminal Q is kept at “L”.

Further, when only the pulse P _C is outputted from the control circuit 14, inverted to 'H' from the terminal Q of the flip-flop 17 is 'L', the two input terminals of the AND circuit 18 becomes 'H', the The output becomes “H”, and the output of the OR circuit 19 also becomes “H”. Also at this time, the recording paper C is sent by one step, the ink jet head 9 is located at d _{n + 2,} and the output of the OR circuit 19 is “H”, so that the ink droplets are ejected onto the recording paper C and the dots d _{n +} Attach ₂ .
The reset terminal R of the flip-flop 17 also becomes “H”, and the reset is performed. In this case, since the terminal Q is already “H”, only the “H” state of the terminal Q is maintained.

As described above, when there is no movement in the X-axis direction, dots are added every other dot, and the added dots are prevented from blurring. Then, it is possible to prevent the line of the recorded waveform from becoming thicker at a position where there is little change in the X-axis direction.

In the above embodiment, the resolution ratio between the X axis and the Y axis is 1: 2.
In the above, an example is described in which two pulses are divided into one pulse. However, the present invention is not limited to this, and the design can be changed as appropriate.

(F) Effects of the Invention As described above, the waveform recording apparatus of the present invention divides the frequency of the pulse of the pulse motor having the higher resolution in two orthogonal directions, and inputs the frequency to the inkjet head. It is characterized by having means
It has the advantage of drawing waveforms with uniform lines.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a circuit configuration of a waveform recording apparatus according to an embodiment of the present invention, FIG. 2 is a perspective view of a mechanism of the waveform recording apparatus, and FIG. FIG. 4 is a time chart for explaining the operation of the waveform recording apparatus, and FIGS. 5 (a) and 5 (b) are thermal print heads and ink jet heads, respectively. FIG. 6 is a diagram illustrating a waveform drawn by a conventional waveform recording apparatus. 9: the inkjet head, 14: control circuit, 17: flip-flop, 18: the AND circuit, M _P: Penmota, M _C: Chart motor.

Claims (1)

(57) [Claims] An ink jet head facing a recording sheet, and a first pulse motor and a second pulse motor for performing relative movement in two orthogonal directions between the ink jet head and the recording sheet; When a pulse of the first pulse motor or a pulse of the second pulse motor is inputted, in the waveform recording apparatus in which the ink jet head ejects ink droplets on the recording paper, in the two orthogonal directions, A waveform recording apparatus comprising frequency dividing means for dividing a pulse of a pulse motor having a higher resolution and inputting the divided frequency to the ink jet head.