JPH11320940A - Recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To utilize power effectively by an arrangement wherein a motor power control means determines the power of a carrying pulse motor, when it is switched to low level, as the recording power for a recording element. SOLUTION: Coil current of a pulse motor is increased/decreased depending on the level of an MAC signal (control signal) for controlling the coil current. The motor coil is driven with a constant current and a large current is fed to the motor coil when the MAC signal has H level whereas a small current is fed to the motor coil when the MAC signal has L level. During time intervals of t1-t4 and t5-t6, the MAC signal goes H to increase motor power and maximum level of recording power is lowered because the number of black pixels to be driven is limited. Since recording power is suppressed and excess power can be distributed as motor power, power can be utilize effectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording apparatus, and more particularly, to a lightweight, small, and low power consumption recording apparatus mounted on a portable FAX or the like driven by a battery or the like.

[0002]

2. Description of the Related Art In recent years, in a recording apparatus of this kind (for example, a thermal printer), when the apparatus is driven by a battery,
Efforts have been made to reduce size and weight by reducing maximum power consumption and energy consumption.

[0003]

However, the capacity of a power supply such as a battery must have a value obtained by summing at least the power consumption of the pulse motor, the power consumption of the thermal head, and the power consumption of other control units. Yes, a large capacity power supply is required. Therefore, this is a bottleneck, and there is a limit in reducing the size and weight of the device.

That is, if the miniaturization of the power supply circuit itself is forcibly prioritized, the recording time increases, and it is difficult to achieve both the recording performance of the apparatus and the reduction in size and weight of the apparatus by reducing the capacity of the power supply. is there.

The present invention has been made in view of the above problems, and has as its object to achieve a further reduction in size and weight of a recording apparatus without lowering recording performance.

[0006]

In order to achieve the above object, the present invention has the following arrangement.

According to a first aspect of the present invention, there is provided a recording apparatus which divides a plurality of recording elements into units of a predetermined number of recording elements and performs recording. Motor power control means for controlling the switching of the transfer pulse motor, and when the power of the conveying pulse motor is weakly switched by the motor power control means, the power corresponding to the power is used as the recording power for recording the recording element. Recording power control means for controlling the recording power.

After the displacement of the recording medium is stopped, attention is paid to the fact that there is no problem even if the current supplied to the transport pulse motor is reduced, and the amount of current supplied to the transport pulse motor is dynamically switched and controlled. The extra power is passed to the recording power. As a result, the peak value of the required power can be reduced, and the power supply can be reduced in size.

According to a second aspect of the present invention, in the recording apparatus according to the first aspect, the motor power control means reduces a current flowing through the motor coil after the recording medium is displaced by the motor pulse signal. And

After the displacement of the recording medium is completed, the electric current supplied to the motor coil is switched to a small value to reduce the electric power of the motor. Thus, the motor power can be dynamically switched and controlled during the recording.

According to a third aspect of the present invention, in the first aspect of the present invention, the recording power control means controls the black pixels to be simultaneously recorded when the power of the conveying pulse motor is switched to a low level. The number is increased.

By increasing or decreasing the number of black pixels to be recorded simultaneously, the recording power can be dynamically controlled during recording.

According to a fourth aspect of the present invention, there is provided a recording apparatus which divides a plurality of recording elements into a predetermined number of recording element units and performs recording, wherein the driving timing of the recording medium conveyance by the first pulse motor force and the first recording motor are controlled. The recording timing of the recording element according to the number of black pixels is synchronized with the driving timing of recording medium conveyance by the second pulse motor force smaller than the first pulse motor force and the second black pixel number larger than the first black pixel number. The recording timing of the recording element is synchronized with the recording timing.

By synchronizing the recording timing of a predetermined number of black pixels with the timing of driving the recording medium to be conveyed by a predetermined pulse motor power, efficient recording can be performed by effectively utilizing power. This makes the device smaller and smaller.
Weight reduction is achieved.

According to a fifth aspect of the present invention, there is provided a recording apparatus for recording an image on a transported recording medium by driving a plurality of recording elements in units of a predetermined number of recording elements. The driving timing of the pulse motor for transporting the recording medium and the timing for driving the first predetermined number of recording element units are overlapped, and the non-driving timing of the pulse motor for transporting the recording medium and the first predetermined number are compared. The timing for driving the second predetermined number of recording element units, which is often the case, is overlapped.

By driving a different number of recording elements in synchronization with the drive timing and the non-drive timing of the transport pulse motor, power can be effectively used and efficient recording can be performed. As a result, the size and weight of the device can be reduced.

According to a sixth aspect of the present invention, there is provided a recording apparatus, comprising: an image input unit; a transport motor for displacing a recording medium; a recording unit for recording on the recording medium; And power control means for controlling the power of the transport motor and the power of the recording means, wherein the power control means is configured to control the power of the transport motor based on a black ratio of an image input from the image input means. And the power of the recording means is increased when the power of the transport motor is reduced.

By controlling the power of the transport motor and the power of the recording means in a complementary manner based on the black ratio of the input image, the power can be used effectively and the recording can be performed efficiently. This makes it possible to reduce the size and weight of the device.

[0019]

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

FIG. 1 is a block diagram of a recording apparatus (thermal printer) according to the present embodiment.

The image input means 1 is used for inputting an image signal (raster data) to the main body of the recording apparatus. For example, when the recording apparatus is used as a recording unit of a facsimile apparatus, a scanner for reading a document, a decoding unit for received data, and the like correspond to the image signal input unit 1.

The line memory 2 is provided for buffering the image signal input from the image signal input means 1.

The control unit 3 controls the recording of the image signal input from the line memory 2 and the rotation of the conveying pulse motor 8. The control unit 3 includes a black pixel counting unit 4 for recording control.

The black pixel counting section 4 counts the number of black pixels of the image signal (PIX A) from the line memory 2. The control unit 3 uses the count value of the black pixel counting unit 4 to complementarily control the power of the transport motor and the recording power, and effectively uses the power. The black pixel counting unit 4
The thermal head 5 transmits serial image data (PIX B), a latch pulse (LATCH), and drive enable signals (ENA A, ENA B) for two types of heating elements.
To supply. The control of the recording power using these signals will be described later.

The thermal head 5 has a plurality of heating elements arranged in the main scanning direction of the recording paper, and heat-sensitive paper (recording paper) is made black, for example, by the heat generated by the heating elements (not shown in FIG. 1). The desired recording (printing) is performed by changing.

The motor driver 6 is a motor driver for driving the pulse motor 8 for conveying the recording paper, and has a power control circuit 7 built therein. A pulse (M) for rotating the pulse motor 8 is transmitted from the control unit 3 to the motor driver 6.
P) and a control signal (MAC) for controlling the coil current of the pulse motor 8 are supplied. The power control circuit 7
The driving condition of the pulse motor 8 is changed using these signals to control the motor power. This will be described later.

The power supply section 9 supplies a power supply voltage to the thermal head 5, the motor driver 6, and other parts, and includes a battery (battery pack) 10 and a DC / DC converter for obtaining a desired level of voltage. 11 is provided.

FIG. 2 is a diagram showing a configuration of a main part of the thermal head. In the main scanning direction of the thermal head 5, a plurality of heating elements (TM) are arranged in series. The number of heating elements is, for example, 1,728 in the case of A4 size. The pulse motor 8 shown in FIG. 1 is transmitted to a platen roller 13 for conveying the recording paper via a power transmission means (not shown) such as a gear. When the platen roller 13 rotates, the recording paper 14 (contained in a roll shape in FIG. 2) is pulled out by an amount corresponding to the rotation.

FIG. 3 is a diagram showing a configuration for driving a heating element in the thermal head.

As described above, the plurality of heating elements TM (1) to
TM (2n) is linearly arranged in the main scanning direction.
In the present embodiment, a plurality of heating elements TM (1) to TM (2
n) is divided into a first group (TM (1) to TM (n)) and a second group (TM (n + 1) to TM (2n)), and the first group is driven. (When in driving state)
The second group is in the non-driving state, and when the second group is in the driving state, the first group is in the non-driving state.

As described above, when a plurality of heating elements are divided into a plurality of groups and time-division driving is performed, the temperature of the heating elements constantly rises and the temperature control becomes impossible when the switch is always on. This is because a non-heating period is always provided after the heating period to lower the temperature of the heating element. The operating states of the first group and the second group are respectively controlled by enable signals (ENA A, ENA B) supplied from the black pixel counting section 4 in FIG.

One end of each of the heating elements TM (1) to TM (2n) is connected to a power supply voltage (VH) supplied from the power supply section 9 in FIG. 1, and the other end of each of the heating elements is a NAND gate NA. (1) to (2n) are connected to output terminals.

The NAND gates NA (1) to NA (2n) are gates for driving the heating elements TM (1) to TM (2n), and correspond one-to-one with each heating element. Reference numeral 15 denotes an image signal (PI
XB) is a shift register that converts XB) into parallel data and holds it. Reference numeral 16 denotes a latch circuit that holds an image signal of a recording line. This latch circuit 16
Output of each stage are NAND gates NA (1) to NA (2n)
Is one of the inputs. The latch timing is shown in FIG.
Latch pulse (LATCH) supplied from the control unit 3
Is controlled by

Next, a mechanism for controlling the power of the pulse motor 8 will be described with reference to FIG.

FIG. 4 shows a configuration of a main part of the power control circuit 7 and a main part of the pulse motor 8 incorporated in the motor driver 6 of FIG. In FIG. 4, reference numeral 1
Reference numeral 7 denotes a rotor made of a magnet, and A and B each represent a coil (winding). Taking the coil A as an example, the current (I) flowing through the coil is determined by the ON time of the switch 20 per unit time. The opening and closing of the switch 20
It is controlled by an on / off control circuit 19.

The on / off control circuit 19 compares the voltage between both ends of the current detecting resistor 18 with a reference voltage, for example.
When the voltage at one end of the resistor 18 exceeds the reference voltage, the switch 20 is turned off to cut off the current, and when the voltage at one end of the resistor 18 becomes lower than the reference voltage, the switch 20 is turned on. Thus, the current I flowing through the coil A is controlled in proportion to the reference voltage. By changing the reference voltage according to the MAC signal (coil current control signal) supplied from the control unit in FIG. 1, the current flowing through the coil A per unit time can be controlled, and the motor power can be adjusted. Becomes possible. The current amount can be similarly controlled for the coil B.

In this embodiment, the recording power and the motor power are controlled in a complementary manner by using the above-described configuration, and efficient recording without waste is performed.

The operation of the recording apparatus according to the present embodiment will be described below with reference to FIGS. 1, 5 and 6.
FIG. 5 is a timing chart showing the operation of the recording apparatus of the present embodiment, and FIG. 6 is a timing chart showing the operation of a comparative example (an example not using the present invention). Note that the comparative example of FIG. 6 is provided to clarify the power reduction effect of the recording apparatus of the present embodiment.

First, the basic operation of the recording apparatus will be described with reference to FIG.

The black pixel counting section 4 provided in the control section 3 shown in FIG. 1 provides an enable signal (ENA) for the image signal (PIX A) input from the line memory 2.
A, ENA B) corresponding to each of the image signals (PI
It is determined whether the number of black pixels in XA) is equal to or less than a predetermined number. In other words, the ratio (black ratio) of the area of a portion where data is recorded to the area of a certain region is
The judgment is made using a threshold value. For example, if all the data is recorded in a certain area and the area turns black, the black ratio of the area becomes 100
%, And 0% if not recorded at all. The higher the black ratio, the higher the battery voltage (recordable voltage, recording power) required to record data.

In the present embodiment, because of the dynamic switching control of the recording power, "N1" and "N2" are used as "predetermined thresholds" for determining the number of black pixels.
One value is used and these are used depending on the period (this point will be described later).

If the number of black pixels is equal to or smaller than "N1 (or N2)", the black pixel counting section 4 outputs the image signal (PIX).
A) is output to the thermal head 5 as an image signal (PIX B) without processing.

An image signal (PIX) is applied to the thermal head 5.
After B) is input, a latch pulse (LACTH) is input. Subsequently, the enable signals (ENA A, E
NAB) are turned on for a predetermined time, respectively.
The heating elements (TM (1) to TM (2n) in FIG. 3) generate heat, and a thermal recording paper (reference numeral 14 in FIG. 2) sandwiched between the thermal head 5 and a platen roller (reference numeral 13 in FIG. 2).
Color. At the same time, by inputting a motor pulse (MP) to the motor driver 6, the motor driver 6 drives the pulse motor 8 and conveys the recording paper in the sub-scanning direction by a minute predetermined amount via the power transmission means and the platen roller. . Thus, an image for one line is recorded.

On the other hand, as a result of counting by the black pixel counting section 4, the number of black pixels corresponding to each of the two enable signals (ENA A, ENA B) of the image signal (PIX A) becomes a predetermined number "N1 (or N2)". ) "), The current capacity of the power supply unit 9 is limited.
One driving of the heating element does not allow the black pixels in one line to be colored at a stroke. So, in this case,
The number of heating elements (TM) that are driven simultaneously is limited, and printing is performed several times in a time-division manner to record one line.

That is, the enable signal (ENA A,
The number of black pixels corresponding to ENA B) is a predetermined number “N1 (N
2), the black pixel counting unit 4 outputs an image signal (PI) masked with white data so that the number of black pixels is equal to or less than “N1 (N2)” with respect to the image signal (PIXA).
XB) is processed and output. Printing is performed in a time-division manner using such processed data with the white mask.

Next, specific operation timing will be described with reference to FIG.

The data (PIX) shown at the top of FIG.
B) D1 is data of one line (input image data that is not processed) in which the number of black pixels is smaller than the predetermined number “N1 or N2”. In the drawing, the oblique lines given to the data D1 (the same applies to D2 to D7) indicate a portion of one line of data which is transferred to the printhead as valid data without white masking (that is, a valid recording portion). Is shown. That is, the data D1 is hatched throughout, but this is because the data D1 for one line is all
This indicates that the data can be transferred and recorded in one data transfer.

That is, the image data D1 stored in the shift register 15 of FIG.
1 is latched by the latch circuit 16 of FIG. on the other hand,
The enable signal (ENA A) goes high at time t1 to enter the active state. As a result, the corresponding heating element of the first group of heating elements TM (1) to TM (n) in FIG. 3 is driven, and printing is performed.

In synchronization with the positive edge of the enable signal (ENA A), two motor pulses (M
P) Q1 and Q2 are output. Similarly, when the enable signal (ENAB) changes to a high level at time t2 to be in an active state, the second group of heating elements TM in FIG.
The corresponding heating element of (n + 1) to TM (2n) is driven to perform printing, and the enable signal (ENA)
Two motor pulses (MP) Q3 and Q4 are output in synchronization with the positive edge of B).

That is, in this embodiment, every time half of the data of one line is recorded, two motor pulses (M
P) is supplied to the motor driver 6. It is to be noted that how many pulses are assigned when one line is printed is a matter of design. In this example, four pulses are assigned to one line of printing. The pulse motor 8 is rotated by the four pulses Q1 to Q4, the platen roller 13 is rotated, and the recording paper is displaced in the sub-scanning direction by an amount corresponding to one line during the period from time t1 to t3 (see FIG. 5). The amount of change in the sub-scanning direction of the recording paper is shown in the middle row).

A period T11 (time t1 to t3) is a recording period of the image data D1. For general office manuscripts,
The ratio of black pixels in a document is only a few percent, and processing such as period T11 is performed on many recording lines.

However, depending on the type of the original, there is a case where the amount of black is extremely large.
As in t7, data transfer is performed a plurality of times using processing data D2 to D7 masked with white data so that the number of black pixels is equal to or less than a predetermined number, and one line is printed.

In FIG. 5, period T12 (time t3 to t7)
Is a period in which the recording process is performed in a divided manner. In the present embodiment, the period T12 is further divided into periods T13 to T16. The periods T13 and T14 correspond to the enable signal (ENA).
This is a recording period corresponding to A). Enable signal (E
The period including the timing when NA A) is first turned on is T
13, and the others are T14. Similarly, the period T15
And T16 are periods corresponding to the enable signal (ENAB). A period including a timing when the enable signal (ENAB) is first turned on is defined as T15, and the other period is defined as a period T16.

At time t3, the enable signal (ENA)
A) becomes active and two motor pulses (MP) Q5 and Q6 are output in synchronization with this, whereby the recording paper is displaced during the period from time t3 to t4. Similarly, at time t5, the enable signal (ENAB) becomes active, and two motor pulses (MP) are synchronized with this.
Q7 and Q8 are output, whereby the recording paper is displaced during the period from time t5 to t6.

When the above-described series of recording is performed, it should be noted that the recording power (shown in the second row from the bottom in FIG. 5) and the motor power (shown in the bottom row in FIG. 5). Is the relationship.

In the present embodiment shown in FIG. 5, a MAC signal for controlling the coil current of the pulse motor 8 is input to the motor driver 6, and the coil current does not increase or decrease according to the level of the MAC signal. As described above.
That is, the motor coil is driven at a constant current, and M
When the level of the AC signal is “H”, a large current flows through the motor coil, and when the level of the MAC signal is “L”, a small current flows through the motor coil.

In FIG. 5, at times t1 to t4 (period "T
11 "," T13 ") and times t5 to t6 (period" T1
5)), the MAC signal becomes “H” level, and accordingly, the motor power increases to “MW2 (for example, 3W)”. This is because this period is a period during which the recording paper is displaced, and it is necessary to increase the current flowing through the motor coil to generate a desired motor torque.

On the other hand, time t1 to t4 and time t5
In each of the periods from t6 to t6, the upper limit of the number of black pixels that can be driven simultaneously is suppressed to "70", and as a result, the maximum value of the recording power is reduced to "RW2". The numbers (50, 70, 70, 9) described in the recording power graph of FIG.
0, 90, 85, 70, and 80) indicate the number of black pixels recorded simultaneously.

That is, the recording power is suppressed, and the recording power is allocated to the motor power. Thereby, effective use of electric power can be achieved.

Next, at times t4 to t5 in FIG.
4 ") and the period from time t6 to time t7 (period" T16 "), during this period, the MAC signal (coil current control signal of the pulse motor) is at the low level,
Accordingly, the motor power becomes “MW1 (for example, 1 W)”.
It is suppressed to. In this period, there is no need to displace the recording paper, so that the motor power is kept low.

That is, every time one pulse of the motor pulse (MP) is input, the motor rotates by a predetermined angle to displace the recording paper, but after the displacement is completed and the recording paper is stopped, the pulse motor is stopped. Requires only the small coil current required to hold the rotor in place,
It is not necessary to constantly supply a large current as in the prior art, and useless driving by such a large current causes only heat generation of the motor and wastes energy. Focusing on this point, in the present embodiment, a minimum current sufficient to maintain the position of the rotor is applied only when necessary, and the coil current is dynamically switched during recording.

In FIG. 5, the periods "T14" and "T1"
The current flowing through the motor coil in “6” is the period “T1”.
The current is reduced to about one third of the current flowing through the motor coil at “3” and “T15”. Since the recording paper is stopped, the stepping-out of the pulse motor does not occur even if the drive current of the motor is reduced.On the other hand, during this period, the amount of the reduced motor power is allocated to the recording power, and the recording power is reduced. It is raised to “RW1 (for example, 9W)”. As a result, in the period from time t4 to t5 (period “T14”) and time t6 to t7 (period “T16”), the maximum value of the number of black pixels that can be simultaneously recorded is “90”, and the recording performance is improved. . Therefore, even if the line has a lot of black, the situation that the recording time is greatly increased does not occur.

In this embodiment, since the recording power is dynamically increased or decreased, it is necessary to change the threshold value in the processing of image data (white data mask) when time-division printing is performed. . For example, N1>
If N2, the period “T13” and the period “T15”
Then, the black pixel counting unit 4 in FIG.
An image signal (PIX B) masked with white data so as to be 2 ”or less is generated and supplied to the thermal head 5. In the periods “T14” and “T16”, if the number of black pixels exceeds “N1”, the black pixel counting unit 4 determines that the number of black pixels is N1 or less for the unrecorded portion of the image signal (PIX A). An image signal (PIX B) masked with white data is supplied to the thermal head 5 such that

In FIG. 5, the recording power “RW1” is 90 at maximum.
This is the power that can drive the heating elements simultaneously. Assuming that the power consumed by one pixel of the thermal head is 0.1 W, RW1
= 9W. The recording power “RW2” is 70 at the maximum.
RW2 =
7W. The “MW2” of the motor drive power is 3W
And “MW1” is about 1 W, which is そ の of that.

Therefore, the sum of the recording power and the motor power is leveled (stabilized) as indicated by the thick dashed line in the recording power column (second stage from the bottom) in FIG. 5, and its maximum value WMAX1 Is about 10W (= 9W + 1W).

FIG. 6 shows a case where the conventional control is performed without performing the dynamic control of the recording power and the motor power as in the present invention. That is, in FIG. 6, a constant power (MW0) is always consumed in the pulse motor, and the recording power is also constant for a fixed pixel (for example, 9 pixels).
0 pixels) are always secured for driving simultaneously. For this reason, the power supply unit must have a capacity obtained by adding the maximum value of the recording power and the maximum value of the motor power.

The motor power “MW0” of the apparatus of the comparative example in FIG. 6 is about 3 W, the recording power “RW0” of the thermal head is 9 W, and the maximum power WMAX0 obtained by adding the recording power and the motor power is 12 W. Would. That is, the maximum value of the power consumption (indicated by the thick dashed line in the column of the recording power in FIG. 6) increases by about 2 W as compared with the case where the present invention is applied. In addition, in the case of FIG. 6, the power consumption fluctuates with time, and this is wasteful.

As described above, in the present embodiment, the capability of the power supply unit is effectively allocated to “recording” and “motor drive”, so that efficient recording without waste is possible. Therefore, the power supply unit itself can be further reduced in size and weight. Therefore, the miniaturization and weight reduction of the recording device itself is realized.

[0069]

As described above, according to the present invention, the capability of the power supply unit is effectively allocated to "recording" and "motor drive", so that the power supply unit itself can be further reduced without adverse effects such as an increase in recording time. Smaller and lighter. Therefore, the miniaturization and weight reduction of the recording device itself is realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a recording apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a device configuration around a thermal head.

FIG. 3 is a block diagram showing a specific configuration of a main part of the thermal head.

FIG. 4 is a diagram illustrating a characteristic configuration of a pulse motor and a power control circuit.

FIG. 5 is a timing chart showing the operation of the recording apparatus according to the embodiment;

FIG. 6 is a timing chart showing an operation of a recording apparatus of a comparative example (conventional example).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image input means 2 Line memory 3 Control part 4 Black pixel count part 5 Thermal head 6 Motor driver 7 Power control circuit 8 Pulse motor 9 Power supply part 10 Battery 11 DC / DC converter

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B41J 29/38 B41J 3/20 115F H02P 8/12 H02P 8/00 B

Claims (6)

[Claims] 1. A printing apparatus for printing by dividing a plurality of printing elements into a predetermined number of printing element units, wherein motor power control means controls switching of power supplied to a conveying pulse motor during conveyance of a printing medium. Recording power control means for controlling when the power of the conveying pulse motor is switched to low by the motor power control means, so that the corresponding power is used as recording power for recording of the recording element. A recording device, characterized in that: 2. The recording apparatus according to claim 1, wherein the motor power control means sets a small current to be supplied to the motor coil after the recording medium is displaced by the motor pulse signal. 3. The recording power control means increases the number of black pixels to be recorded simultaneously when the power of the conveying pulse motor is switched to a low level.
The recording device according to any one of the preceding claims. 4. A printing apparatus for printing by dividing a plurality of printing elements into a predetermined number of printing element units and printing the printing elements by a drive timing of printing medium conveyance by a first pulse motor force and a first number of black pixels. Synchronize with timing,
The drive timing of recording medium conveyance by the second pulse motor force smaller than the first pulse motor force is synchronized with the print timing of the printing element by the second black pixel number larger than the first black pixel number. Recording device. 5. A recording apparatus for recording an image on a recording medium to be conveyed by driving a plurality of recording elements by dividing the recording element into a predetermined number of recording element units. The drive timing and the timing for driving the first predetermined number of recording element units are overlapped, and the non-drive timing of the pulse motor for transporting the recording medium and the second predetermined number of recordings greater than the first predetermined number are recorded. A recording apparatus, wherein a timing for driving an element unit is overlapped. 6. An image input unit, a conveying motor for displacing a recording medium, a recording unit for performing recording on the recording medium, a power supply unit equipped with a battery, and a power supply for the conveying motor. Power control means for controlling the power of the recording means, the power control means increases and decreases the power of the transport motor based on the black ratio of the image input from the image input means, A recording apparatus, wherein the power of the recording means is increased when the power of the transport motor is reduced.