JP2002311114A - Small sized electric apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To precisely indicate the power feed stop to a main load 2 and the switching time of the indication content to give a sense of safety to an operator, and reliably indicate the remaining capacity in a method of indicating the capacity of a secondary cell 1 for feeding the main load 2 such as motor with power. SOLUTION: After stopping feeding a main load 2 with power and a further short time lapse, the remaining capacity is indicated for a specified time. The detecting operation of the remaining capacity is conducted in a period from the power feed stop to the remaining capacity indication with an indication showing in operation for detecting the remaining capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable small-sized electric appliance using a secondary battery such as an electric razor as a driving source, and more particularly to a portable electric appliance having a battery remaining capacity display.

[0002]

2. Description of the Related Art Conventionally, this kind of remaining capacity display is often displayed during the ON period of a main switch of a device whose remaining amount is to be displayed or during standby. It is also conceivable that the display is stopped after the remaining amount is displayed for the set time continuously after the main switch is turned off.

[0003]

However, this kind of remaining amount display often simultaneously functions as a pilot lamp for indicating the driving state of the main load. In this case, the remaining amount display is displayed by the main switch. If the main load continues regardless of the on / off state, the off time of the main load becomes unclear, and there is a fear that anxiety may be given to a person having hearing impairment.

The present invention has been made in view of the above-mentioned inconvenience. The remaining load is displayed for a predetermined time after a predetermined time has elapsed since the main switch was turned off, so that the stop state of the main load is clearly displayed. Accordingly, it is an object of the present invention to provide a small electric device that gives a sense of security to an operator and that can display an accurate remaining amount.

[0005]

As shown in FIG. 1, a small electric device according to the present invention is provided with a battery 1 such as a secondary battery and a drive power supplied from the battery 1. A main load 2 such as a motor, operating means 3 for turning on / off the energization timing for the main load 2, a battery capacity detecting means 4 for detecting the remaining capacity of the battery 1, and a current capacity of the battery 1. And a battery capacity display means 5 for enabling a corresponding display.

Further, in the present invention, the battery capacity display means 4 performs the display operation for the second set time T2 after the first set time T1 has elapsed since the power supply to the main load 2 was stopped. Features.

The battery capacity detecting means 5 performs a predetermined detecting operation within a first set time T1, and the battery capacity displaying means 5 displays a display corresponding to the remaining capacity detected by the detecting operation. 2 within the set time T2. The operation of detecting the remaining capacity, which is performed during the first time T1, can be performed by estimating the return voltage from the tendency of the terminal voltage to increase due to the stoppage of power supply to the main load 2. Further, during the first set time T1, it is preferable that a display indicating that the detection operation is being performed is simultaneously performed.

The battery capacity detecting means 4 can be configured so as to detect the battery capacity even while the main load 2 is energized, and to display an indication corresponding to the detected battery capacity on the battery capacity displaying means 5. . In this case, the remaining capacity at the time when the power supply to the main load 2 is stopped is stored, and a display corresponding to the stored remaining capacity is performed on the battery capacity display means 5 during the second set time T2. Is also possible.

[0009]

As described above, according to the present invention, by displaying the capacity after the lapse of the first set time T1 after the current supply to the main load is stopped, a different display is displayed immediately after the main switch is turned off. As a result, the user can visually recognize the stop state of the main load performing the main operation of the device, and can give a sense of security, particularly to a user who is deaf. In addition, by continuing the capacity display performed thereafter for the second set time, it is possible to perform an accurate display operation for the user while saving power.

Further, by performing the remaining capacity detection operation during the remaining capacity display stop period provided immediately after the main switch is turned off, it is possible to detect a state in which the supply of power to the main load is stopped and the terminal voltage of the battery is restored. The true remaining capacity can be accurately detected and displayed.

In addition, the operation of detecting the remaining capacity is performed by estimating from the tendency of the terminal voltage of the battery to increase.
The detection and display operation can be performed in a short detection time.

Further, by positively indicating that the detection operation is being performed during the above-described period of the suspension of the capacity display, an accurate capacity display operation that accurately captures the current state of the battery can be performed.

[0013] Further, the battery capacity is detected while the main load is energized, and a display corresponding to the detected content is performed. When the main load is driven, the capacity display indicates that the main load is operating. And the operating state of the main load can be displayed at the same time. In this case, the change of the display means from the pilot lamp while the main load is being driven to the remaining capacity display after the drive is stopped is clearly confirmed by the existence of the above-mentioned display stop period.

Further, the remaining amount immediately before turning off is displayed during the second setting time without detecting the remaining amount after the power supply to the main load is stopped, so that the first setting time can be minimized. The remaining amount display operation can be performed immediately after the main switch is turned off without providing a waiting time.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A small electric apparatus according to the present invention will be described below based on an example in which a rotary electric shaver illustrated in FIG. 2 is used, but the present invention is not limited to this. Of course, the present invention can be carried out in a similar manner for various small electric devices such as an electric razor rotating around an axis, or a massager, an electric toothbrush or a nail polisher having an operation speed control function of a driving part such as a motor or a vibrator. It is.

As shown in FIG. 2, the electric shaver 10 is provided at the upper end position of a main body case 11 with a head portion 13 which accommodates an inner blade 12 and which is open at the top and is swingable. An outer blade holder 15 having a mesh blade-shaped outer blade 14 in contact with the inner blade 12 is provided so as to close.

The inner blade 12 has a cylindrical shape with a helical blade portion provided on a peripheral surface thereof. A rotating shaft 16 extends outward from both ends thereof, and is horizontally supported above the head portion 13.
One of the rotating shafts 16 and the rotating shaft of the motor 17 are connected by a reduction mechanism (not shown) including a plurality of gears or a timing belt.

On the front side of the main body case 11, there are provided a main switch 19 for regulating the motor 17 on and off, and a drive speed of the motor 17 on an operation panel 18 which extends longitudinally in the form of a strip extending vertically to the center. And a second display for displaying the drive mode of the motor 17. The first display unit 21 includes three light emitting elements 20 a, 20 b, and 20 c for displaying
A display unit 22, a sub-switch 23 for changing a driving state of the motor 17, and a third display unit 2 for displaying a charging time.
And a fourth display unit 25 surrounding the operation panel 18 and capable of displaying the remaining battery capacity as shown in FIG.

A socket 28 is provided at the lower end of the main body case 11 so that the plug 27 of the charging adapter 26 can be removably connected thereto. The electronic circuit 31 shown in FIG. It can be driven using a power supply.

The charging adapter 26 is connected to a commercial AC voltage 3 of about 100 to 250 V input through a power plug 29.
0 is rectified after being stepped down by an inverter circuit (not shown) having substantially the same configuration as that of the
And a DC low voltage charging voltage Vd slightly higher than the terminal voltage Ve of, for example, about 4 V.

As the main switch 19 and the sub-switch 23, for example, a push-type normally open switch is used, and each time the push operation is performed, the electronic circuit 31 performs a preset operation described later.

The first to third display sections 21, 22 and 24 are provided with one or more light emitting elements, such as red light emitting diodes, whose driving voltage is lower than the battery voltage, separated from each other and their display shapes or display colors. Are provided in a tandem state with different lighting positions or blinking states of the light emitting elements, thereby enabling a predetermined display operation described later.

More specifically, the colors of all three light emitting elements 20 in the first display unit 21 are changed to yellow, and the second display unit 22
Is set to green, and the third light emitting unit 24 is set to red. By changing the display colors of the first display unit 21 and the second display unit 22 in this manner, the movement of the first display unit 21 can be viewed with reference to the second display unit 22. Can be judged quickly and visually. This is especially
This is useful when the rotation speed is displayed by increasing or decreasing the number of lights, instead of the individual lights being displayed on the first display unit 21.

On the other hand, the fourth display unit 25
As shown in (b), a light emitting element 32 such as a blue LED is used, and instead of directly emitting output light,
Using the prism 33 to bend at right angles and input to the lower end of the light guide plate 34, and emit light to the outside of the main body case 11 from the light diffusion plate 35 disposed in close contact with the front side of the light guide plate 34. Thus, light is displayed in a planar manner.

Further, in this embodiment, the light diffusing plate 35 is exposed in a narrow band by making a round around the operation panel 18 and the light 6 output from the light diffusing plate 35 is exposed.
1 is not the same over the entire surface, but is set so that the light incident on the light guide plate 34 is attenuated as going upward, so that the fourth display unit 2
5 is the brightest at the lower end and becomes darker as going upward.
Light is emitted in a substantially U-shape as shown in FIG.

Next, the electronic circuit 31 housed in the main body case 11 is shown in FIG.
A one-chip type microcomputer device 37 is entirely controlled by using a secondary battery 36 capable of charging and discharging a plurality of times as a drive source, and controls a charging timing for the secondary battery 36. And a battery control unit 40 that enables a display corresponding to the remaining battery level during operation by the secondary battery 36 and a motor control unit 40 that allows the drive state of the motor 17 to be changed.

The microcomputer device 37 used in the present invention comprises:
A general-purpose A / D converter having a plurality of analog voltage input ports by incorporating a function as an A / D converter integrally. Can be performed only by the microcomputer device 37 without using individual components such as an A / D converter and a comparator.

That is, after the voltage value input to the input port of the analog signal is compared with the divided voltage value of the reference voltage VS stabilized by the constant voltage circuit 41, the voltage value is converted into a predetermined digital value of about 8 bits. The converted digital values are appropriately compared, and a predetermined operation is performed according to the magnitude. Then, using the A / D conversion function and the calculation function by the program provided in the microcomputer device 37, various detections and display or control operations corresponding to the detection contents are performed.

The secondary battery 36 is a nickel-metal hydride battery. In this embodiment, by connecting two batteries in series, the terminal voltage Ve of the secondary battery 36 becomes 1. Those that vary from about 8 V to about 3.5 V are used. However, it goes without saying that the type or number of batteries can be changed.

As shown in FIG. 5, the charging control unit 38 includes a first transistor 42 provided for switching the charging voltage Vd output from the charging adapter 26 and a temperature fuse 43 for blowing when overheated. By applying the voltage to both ends of the secondary battery 36 through the, the secondary battery 36 can be charged.

That is, when the charging voltage Vd is input, the second transistor 44 connected to the base terminal of the first transistor 42 is first turned on, and then the first transistor 42 is turned on to start charging the secondary battery 36. Let it. At the same time, the light emitting element 45 provided in the third display section 24 is energized to indicate that charging is in progress.

When the charging completion time is reached, the microcomputer device 37 turns on the third transistor 46, and as a result,
The transistor 44 and the first transistor 42 are turned off to stop charging the secondary battery 36,
The energization of the light emitting element 45 of the third display unit 24 is also stopped to notify the operator that charging is completed.

Here, the method of detecting the full charge time of the secondary battery 36 is not particularly limited. However, in the present embodiment, the battery voltage detecting unit 47 that divides the battery voltage Ve is used by taking advantage of the fact that the terminal voltage Ve at the time of charging the nickel-metal hydride battery changes as exemplified in FIG. By inputting a voltage proportional to the battery voltage Ve to the microcomputer device 37 through the microcomputer 37 and detecting a change in the voltage, the terminal voltage Ve of the secondary battery 36 reaches a peak value Vp from the time A, and a predetermined voltage ΔV is further added. Terminal voltage Ve
It is basically determined that the time point B at which the battery charge has decreased is determined to be the time of full charge, and the quick charge is stopped and controlled.

Further, in consideration of the case where the peak value Vp cannot be detected due to the deterioration of the secondary battery 36 or the like, the longest charging time of about one hour is set in advance by the timer function of the microcomputer device 37, and from the start of charging. When the longest charging time elapses without detecting the peak position, charging is forcibly stopped.

At the same time, the surface temperature of the secondary battery 36 is detected by the battery temperature detecting circuit 49 using the thermistor 48, and after the temperature reaches the set value, the set temperature is equal to or higher than the set temperature for, for example, about 10 seconds. Even if it is confirmed that the state described above has been maintained, overcharging is prevented by judging that the battery has reached full charge and stopping charging.

It should be noted that an AC detection section 63 comprising a transistor 62 which is turned on when the charging voltage Vd is input is provided so that the input timing of the charging voltage Vd can be determined, and used for various control operations including the above-described charging control. .

Next, the detection and display of the remaining capacity of the secondary battery 36 utilizes the fact that the terminal voltage Ve decreases with the use of the secondary battery 36 as shown in FIG. In the first embodiment, it is determined that the battery is fully charged until the terminal voltage Ve reaches the first comparison value V1.
The light-emitting element 32 at is always lit to display a full charge.

Further, until the terminal voltage Ve becomes lower than the first comparison value V1 and reaches the second comparison value V2, D, the light emitting element 32 is slowly blinked at intervals of about one second to display a charge notice display. The display control operation is shifted to the charge prompting display for shortening the blinking cycle when the voltage falls below V2.

In order to realize the above-mentioned operation, in this embodiment, as shown in FIG. 7, the voltage stabilized by the constant voltage circuit 41 is used as a reference voltage VS at the time of A / D conversion, and the voltages are compared. By dividing the voltage in the voltage generation circuit 50, the first comparison value V1 and the second comparison value V2 are formed.

At the same time, the secondary battery voltage Ve is divided by the battery voltage input circuit 51 and input to the microcomputer 37, and the input value is compared with the above-mentioned comparison values V1 and V2 to calculate the current remaining battery level. And the result of the
It is displayed on the display unit 25.

In this embodiment, a light emitting element having a higher driving voltage than the terminal voltage Ve of the secondary battery 36, such as a blue LED, is used as the light emitting element 32 provided in the fourth display section 25. ing.

Therefore, the terminal voltage Ve of the secondary battery 36 is once increased by the booster circuit 52 to a voltage required for display on the fourth display unit 25, and then applied to the light emitting element 32. Furthermore, since the current flowing through the light emitting element 32 on the fourth display section 25 side is larger than the current flowing through the light emitting elements on the first to third display sections 21, 22, 24, the switching circuit 53 is connected in series with the light emitting element 32. The switching circuit 53 is interposed, and the microcomputer circuit 37 controls the switching circuit 53.
5, the display time can be regulated.

The operation for displaying the remaining battery capacity in the fourth display section 25 can be basically executed during an arbitrary period, such as during the ON period of the motor 17. Especially motor 1
During the ON period of 7, it simultaneously serves as a pilot lamp indicating that the motor 17 is being driven.

However, as shown in FIG. 8 (e), during the period from time t1 to t2 when the motor 17 is being driven, the secondary battery 36 is not driven.
Of the terminal voltage Ve continues to decrease, but the terminal voltage Ve returns when the driving of the motor 17 is stopped.

Therefore, in the present embodiment, as shown in FIGS. 8A and 8B, when the motor drive is started at time t1 and then stopped at time t2, the state shown in FIG. As described above, the switching circuit 53 is turned off, and the remaining capacity display operation on the fourth display unit 25 is temporarily stopped until time t3.

On the other hand, even during the suspension period T1 of the remaining capacity display from time t2 to t3, the operation of detecting the remaining battery capacity is continued as shown in FIG. The capacity is held, the display corresponding to the held remaining capacity is performed on the fourth display unit 25 during the period T2 from time t3 to t4, and then the display on the fourth display unit 25 is stopped.

For example, in the case of an electric razor, a lint is accumulated between the outer blade 14 and the inner blade 12 to increase the load. As a result, it is indicated that the remaining battery level is low despite the sufficient battery capacity. The charging may be repeated by the user.
Even in such a case, by detecting and displaying the remaining capacity after the power supply to the motor 17 is stopped, it is possible to accurately confirm whether or not the battery capacity is really remaining.

The period T during which the display is stopped after the motor stops.
1 is a minimum time, for example, about 0.2 to 1 second, which can confirm that the battery voltage has recovered and can express the state before and after the motor 17 is stopped, as shown in FIG. It is preferable to set, but it is needless to say that it can be set arbitrarily.

For example, when a time of 0.2 seconds or less is set, the recovery of the battery voltage is insufficient during that time. Therefore, the recovery rate of the battery voltage is measured, and the final value is obtained from the measured value. Calculate the restoring voltage and estimate the remaining capacity. At the same time, the display indicating that the remaining battery level is being detected is of a simple and easily recognizable type such as simply stopping the display or changing the color because the set time is short.

On the other hand, if the display stop period is a long time such as 1 second or more, the fact that the remaining battery capacity is being detected during that period is indicated by blinking the light emitting element 32, changing the light emitting color, or giving notice by text. By performing the display, the driving of the motor 17 is completely stopped, and the operator can more accurately recognize that the operation of detecting the remaining charge is being performed normally.

In this case, the display performed during the remaining amount display suspension period can be provided by a separate display means, or can be executed by using the fourth display unit 25.
In short, the display contents during and immediately after the drive of the motor 17 are changed to, for example, a stop display if the display is a blinking display before that, and a blinking display if the display is on, thereby changing the display contents. You can check. If it fulfills its role, display means,
Needless to say, both the display method and the display content can be changed as appropriate.

Further, the display on the fourth display unit 25 is increased or decreased in light emission intensity instead of turning on or off one light emitting element as described above, or provided with a plurality of light emitting diodes to increase or decrease the remaining capacity. , The number of lighting of the light emitting elements can be increased or decreased. In addition, instead of displaying the increase / decrease of the number of lights by the light emitting diode, other display means such as a liquid crystal display panel or an EL element is used, and the remaining capacity is displayed by a numerical value such as the number of possible shavings. Can be changed.

However, in any of the display methods described above, immediately after the power supply to the motor 17 is stopped, the display of the remaining amount is temporarily turned off for a predetermined time T1, and thereafter, for a predetermined time T2.
Redisplaying with the content detected during the display off period is the same as in the case described above.

It is also possible to store the remaining capacity immediately before the main switch 19 is turned off, and to display the stored remaining capacity during the post-stop display period T2 performed after the display stop period T1. In this case, the stop display period T1 can be set short, and the display of the remaining amount can be resumed immediately after turning off.

Next, as shown in FIG. 9, the motor control section 40 increases the rotation speed of the motor 17 by, for example, about 8800 rotations per minute and about 8300 rotations per minute by pressing the sub switch 23. "Manual mode" that can be changed to three stages of medium speed and low speed of about 7800 rpm
In addition to the above, an "auto mode" is provided in which a change in the load applied to the motor 17 is detected, and the rotation speed of the motor 17 can be automatically changed in three stages in the manual case in accordance with the change in the load.

The motor 17 used here is provided with the inner blade 12
Is a DC type that drives to rotate, and its rotation speed is determined by the magnitude of the average voltage applied to the motor 17, and corresponds to the magnitude of the load applied to the inner blade 12 when the applied voltage is constant. Then, the operation of detecting the magnitude of the load is performed using the fact that the magnitude of the motor current increases or decreases.

In order to change the rotation speed of the motor 17, a voltage is applied to the motor 17 at all times or almost at a high speed as shown in FIG.
As shown in (b) and (c), the average voltage applied to the motor 17 is reduced by sequentially decreasing the ratio of the voltage application time in one cycle, and the motor rotation speed is increased or decreased. Has adopted.

On the other hand, the detection of the load applied to the motor 17 is performed by interposing a low resistance 54 in series with the motor 17 and extracting a voltage which increases and decreases in proportion to the motor current. Further, the voltage generated at both ends of the low resistance 54 is integrated by the integration circuit 55, so that the detection voltage Vf as shown in FIGS.

Further, the magnitude of the detection voltage Vf is compared with three comparison voltages VH, VM, and VL obtained by dividing the reference voltage VS output from the constant voltage circuit 41 by resistors.
By determining the magnitude relationship between the two, the magnitude of the load applied to the motor 17 is determined in three stages.

Here, in this embodiment, the integration circuit 55
In the case of high-speed and medium-speed rotations in which the idle period of the voltage applied to the motor 17 is short, the time constant in FIG.
As shown in FIG. 1 (a), it is set so as to be smoothed to a state with little ripple.
As shown in FIG. 1B, the waveform is set so as to have a waveform having a large ripple that repeats charging and discharging.

In addition, the comparison voltage formed by dividing the constant voltage circuit 41 is divided into a first comparison voltage generation circuit 56 for medium / high speed and a second comparison voltage generation circuit 57 for low speed. Types are provided so that the comparison voltage can be set and determined based on different standards.

That is, in the motor load detection at the time of middle to high speed, the level of the detection voltage Vf changes little with the lapse of time under the same load condition. As shown in (a), two kinds of high and low comparison voltages VH and VM are set, and the comparison voltage and the detection voltage VH are set.
The magnitude of the load is detected based on the vertical relation of f. For example, when the detection voltage Vf is higher than VH, it is determined that the load is high and the engine rotates at a high speed. When the detected voltage Vf is between VM and VH, it is determined that the load is medium. Control to shift to low-speed rotation is performed by judging that the load state is present.

On the other hand, when the motor 17 is rotating at a low speed, the detection voltage Vf does not change even if the load is the same, as shown in FIG.
It changes greatly as in (b). Therefore, the reference voltage VS is divided to set the comparison voltage VL for low speed only, and the peak level of the detection voltage Vf is determined by the comparison voltage VL as indicated by the dashed line.
When the peak position exceeds the comparison voltage VL as shown by the solid line, it is determined that the load has become a medium load or a heavy load. The control for shifting to the medium speed rotation is performed.

When the remaining capacity is sufficient, the terminal voltage Ve of the secondary battery 36 gradually decreases after the start of driving of the motor 17 to decrease the rotation speed of the motor. The value returns. Therefore, in the present embodiment, the on-time Ta in the first switching circuit 58 is increased stepwise at one minute, two minutes, and three minutes after the start of driving of the motor 17, so that the battery voltage V
The rotation speed is corrected based on the decrease in e.

However, when the remaining battery charge falls below the set value, the amount of voltage drop when the motor is driven is larger than in the case described above, and the amount of return is smaller. Therefore, in this case, in addition to the above-described dynamic correction by increasing the on-time Ta of the first switching circuit 58, the off-period Tb
, A decrease in the motor rotation speed due to a decrease in the terminal voltage Ve of the secondary battery 36 is corrected.

During AC driving using the charging adapter 26, the voltage applied to the motor 36 is higher and more stable than when driving only with the secondary battery 36. Therefore, in this case, the off time Tb of the first switching circuit 58 is increased as compared with the case of the above-described battery drive, and the correction operation is not performed.

In order to perform the control operation as described above, the motor control unit 40 connects the first switching circuit 58 in series with the motor 17, and turns on the second switching circuit that is turned on in conjunction with the pressing operation of the main switch 19. By taking out the terminal voltage Ve of the secondary battery 36 via the normally closed switch 64 which is turned off in conjunction with the removal of the circuit 59 and the outer blade holder 15 and inputting it to the control terminal of the first switching circuit 58 as an ON signal, The one switching circuit 58 is turned on to be in a state where a battery voltage can be applied to both ends of the motor 17.

In this state, the microcomputer device 37 sends the third
The drive signal S applied to the control terminal of the switching circuit 60
By setting k to be the inverse of the waveform shown in FIG. 10, the third switching circuit 60 is turned on and applied to the control terminal of the first switching circuit 58 in response to the “H” level period of the drive signal Sk. The ON signal is short-circuited and turned off, and the motor 17 rotates at a speed corresponding to the length of the ON time Ta of the first switching circuit 58 in one cycle.

The change of the motor rotation speed in three stages is caused by the three light emitting elements 20a, 20b,
It is displayed by changing the lighting position in 20c. That is, the light emitting element 20a at the uppermost position is illuminated to operate at high speed, the light emitting element 20b at the intermediate position is illuminated at medium speed operation, and the light emitting element 20c at the lowermost position is illuminated to display low speed operation. You. Further, the change between the manual mode and the automatic mode is displayed separately by setting in advance that the automatic mode is displayed when the second display unit 22 is on and the manual mode is displayed when the second display unit 22 is off.

As described above, the second display section 22 illuminated in the automatic mode is provided below the light-emitting element 20c for low-speed display in the first display section 21 for displaying the rotational speed of the motor 17 in a stepwise manner. Sub switch 23 for mode switching below
By arranging them in a line in the vertical direction, the mode switching operation can be performed accurately and the operation and control state can be clearly displayed.

The display of the rotation speed on the first display section 21 is performed by the light emitting element 20 corresponding to the current rotation speed as described above.
Instead of turning on only the lights alone, increase or decrease the number of lights in response to the increase in speed, or keep the previous lighting position continuously lit or blink for the set time to have an afterimage effect Can also.

By performing such after-image display, the rotation speed before a predetermined time can be confirmed, and the transition of the speed change can be enjoyed visually. Especially during shaving, for example, the outer blade 1
Even if there is a sudden change in the speed due to the separation of 4 from the skin surface, the rotation speed during the last shaving is displayed as an afterimage using the lighting of the three light emitting elements 20 in the first display unit 21. In this way, it is possible to make an intermediate judgment of unshaving.

Further, by maintaining the above-mentioned after-image display for a predetermined time after the motor driving is stopped, it is possible to determine whether or not there is any remaining shaving when the motor driving is stopped.
The content can be estimated based on the display content of the display unit 21. For example, if the high-speed state is displayed as an afterimage during shaving, or if shaving has been completed in the high-speed state, it is determined that there are many unshaved parts.

In the following, the overall operation of the electric shaver 10 will be described based on the mode transition diagram shown in FIG. 12 and the explanatory diagram of the change of the rotational speed shown in FIGS. The operation procedure will be described in more detail.

In the standby mode in which the electric shaver 10 is not charged and the motor 17 is stopped, all displays are stopped, the operation of the microcomputer device 37 is set to a power saving state, and the consumption of the secondary battery 36 is reduced. Electricity is kept to a minimum.

Here, during the standby mode, the main switch 1
9 is pressed only for a short time, a DC mode driven only by the secondary battery 36 is entered, the power supply to the motor 17 is started, and the motor 17 is driven to rotate. 4 display unit 21.2
The display in 2.24.25 is performed.

If the main switch 19 is pressed again for a short time while the motor 17 is being driven, the power supply to the motor 17 is immediately stopped. However, as shown in FIG. 8D, the display on the display unit is temporarily stopped for a short time of, for example, about 0.2 seconds and then stopped again for a short time of, for example, about 3 seconds. After displaying that the driving operation of the motor 17 has been completed and the detection operation has been performed reliably, a display corresponding to the detection content is displayed, so that the operator can reliably recognize the current operation state.

During the DC mode, the charging adapter 26
Is connected, in addition to the secondary battery 36, the charging adapter 26
Into AC mode with power supply by
When 6 is removed, the mode returns to the DC mode.

If the charging adapter 26 is connected during the standby mode, the charging mode is entered. In this mode,
The capacity detection during charging is performed, and the charging time is displayed on the third display unit 24 in response to the charging. When it is detected that the charging is completed, the charging is automatically turned off, and the third display unit 24 stops displaying the charging operation to display that the charging is completed. Even during the charging mode, when the main switch 19 is pressed and operated, the mode shifts to the AC mode. When the main switch 19 is pressed again, the mode returns to the charging mode.

When the main switch 19 is pressed and operated in the standby mode, the operation is shifted to the DC mode and the motor 17 is turned on as described above, but the pressing operation of the main switch 19 is continued for, for example, about 10 seconds. When,
Enter demo mode. In the demonstration mode, the driving of the motor 17 is stopped and, for example, the fourth display 25
, A demo display for displaying the difference in the display contents is performed.

The display contents and the display method on the display unit described above are merely examples, and the display contents and the display method differ according to various detection contents such as the state of the accumulation of shavings and the degree of the memory effect of the secondary battery 36. Display operation. Further, instead of blinking the light emitting element, the display method can be changed, for example, by changing the light emission intensity or the light emission color of the light emitting element. Furthermore, by using a buzzer or other sounding means to perform display by sound in addition to the above-described visual display, it is possible to more accurately recognize the difference in the use mode.

Here, when the sub-switch 23 is turned on during execution of the DC mode or the AC mode, the motor 17 is operated in the automatic mode, the high-speed rotation drive,
The medium-speed rotation drive and the low-speed rotation drive are sequentially repeated. Just before switching from the automatic mode to the manual mode, a low-speed driving state with no-load operation is common, so by entering the high-speed driving driving state, the switching state is clearly recognized by the user by a change in the motor sound. Can be done.

When the main switch 19 is turned off in the predetermined selection state by the sub-switch 23 to return to the standby mode, the drive state before the off-state is stored. When the main switch 19 is turned on again, the drive mode returns to the drive mode before the off-state. To resume. With such a configuration, the user can select a desired rotation speed, and can use the rotation speed again at the next time, thereby improving usability.
By allowing mode switching by the sub-switch 19 only during driving of the motor, it is possible to prevent an unexpected start of the rotation speed or the driving mode at the next use.

By the way, when the drive mode when the main switch 19 is turned on is the manual mode, even if the stored speed is the middle speed or the low speed, the time t1 to t1 in FIG.
As shown at t2, for example, 1
Until the rotation of the motor for about two seconds is stabilized, a drive signal at the time of high speed is applied to forcibly rotate the motor at high speed, thereby preventing shortage of torque at the beginning of driving.

Similarly, even when the mode at the start of driving is the automatic mode, time t1 to t2 in FIGS.
Immediately after the start of driving, regardless of the magnitude of the load, the high-speed rotation state is first entered and the state is forcibly maintained for about 3 seconds. After that, the system automatically shifts to the middle speed state, and by performing load detection for the first time at this stage, the motor drive and load detection can be started in a stable state. And a display function indicating that the control operation is normally performed.

As described above, by forcibly shifting to the medium-speed driving state, the start of the detecting operation can be confirmed by the auditory sense of the sound change in the drive system including the motor 17 and the light emission content of the display unit. It can be confirmed visually with the change.

The detecting operation may be started in the high-speed driving state or in the low-speed driving state instead of performing the detecting operation in the medium-speed driving state. For example, it does not drop to the medium speed even after a predetermined period of time while maintaining the high speed state, and only when the pressing operation of the skin surface against the outer blade is detected by some method including the pressure sensor and the optical sensor provided on the outer blade is started. By making it possible to shift to medium speed or low speed through rotation control by current detection afterwards, it is possible to always maintain a high speed state until it comes into contact with the skin, eliminating the inconvenience such as motor stop due to insufficient initial torque. Can be.

On the other hand, when the detection operation is started by entering the middle speed position, the transition time to both speeds is short when transitioning to the high speed or low speed state by the rotation control accompanying the detection operation.
The speed transition can be performed smoothly.

Next, when a heavy load is detected during low-speed driving or a light load is detected during high-speed driving, rotation at medium speed is performed instead of immediately shifting to high-speed or low-speed rotation. By shifting to the target rotation speed after the predetermined time has been maintained, a sudden change in speed is avoided, so that the operator does not feel uneasy.

However, if a heavy load is detected during low-speed rotation (see time t5 in FIG. 13), the operation immediately shifts from low-speed rotation to medium-speed rotation, and the medium-speed rotation state is 1
By setting the time to a short time of about seconds, it is possible to shift from the low-speed rotation to the high-speed rotation in as short a time as possible.

Conversely, a medium or light load is detected during high-speed rotation (time t6 in FIG. 13 and time t11 in FIG. 14).
), The vehicle does not immediately shift to the medium speed, but shifts to the medium speed after it is confirmed that the light load continues for about 4 seconds after the heavy load condition is no longer detected, and The medium speed is also set to about 4 seconds, which is sufficiently longer than the medium speed during the transition from the low speed to the high speed.

With such a configuration, during the period of detecting a heavy load during low-speed operation, it is common to start shaving from a no-load state, so that the operator can feel comfortable by making a quick response. At the same time, the presence of the medium speed for a short time reduces the burden on the skin due to a speed change that is too rapid.

On the other hand, during the light load detection period at the time of high-speed or medium-speed rotation, it is common that the load fluctuates greatly due to the repeated operation of separating the outer blade 14 from the beard during shaving. By avoiding frequent speed changes during the period, unpleasant feeling that the speed is not stabilized is prevented beforehand, and a margin period before the next operation is given.

Further, since the rotation speed at the medium speed or the high speed is maintained for at least a predetermined time (four seconds in this embodiment), even when the outer blade 14 is separated from the skin, the inner blade 12 just before the outer blade 14 is separated from the skin. As a result, the display corresponding to the rotation speed of, that is, the magnitude of the load is maintained as it is, so that the intermediate determination of the unshaved portion becomes possible.

Immediately after the transition from the medium speed to the low speed (see times t3 to t4 in FIG. 13), the detection voltage is not stable and erroneous detection is likely to occur. For example, the detection operation is performed for a period of about 1 second. It is set not to be done. As a result, for example, 2
While it can be reached in a short time of about seconds, it takes a long time of at least about 8 seconds from the start of high-speed rotation to the shift to low-speed rotation.

Here, driving at medium speed and load detection are started at time t2 in FIG. 13, but if a heavy load state is detected at that time, the operation immediately shifts to high speed operation without a waiting time. On the other hand, when the medium load is detected during the driving at the medium speed (see time t2 in FIG. 14), the driving at the medium speed is continued as it is, but immediately after the light load is detected at time t3 in FIG. Does not shift, the medium speed state is further maintained for 4 seconds, and after confirming that the light load state is maintained, the state is shifted to the low speed state.

As described above, instead of maintaining the high-speed or medium-speed state for another four seconds after the lighter load state is detected, the timer is forcibly used for four seconds after the high-speed or medium-speed state is reached. The speed state may be maintained, but if a load corresponding to the current speed is not detected immediately thereafter, the speed may be changed immediately. In addition, as long as the control can be performed quickly on the increasing side and slowly on the decreasing side, the maintenance time in each speed state and the timing of changing the speed can be appropriately changed.

Further, when the operation mode is switched to the automatic mode during the operation in the manual mode (see times t3 and t9 in FIG. 15), another one second elapses after the rotation speed is shifted to the medium speed (see FIG. 15). 15 time t4 and t10
By starting the load detection from (see), it is possible to smoothly change the rotation speed and detect the load stably while displaying that the drive mode has been changed from manual to automatic.

As described above, the high-speed operation is continued for a predetermined time of about 3 seconds immediately after the start of driving of the motor 17 in the automatic mode, and the detection operation is started after the medium speed is reached. At the time of high speed rotation one second after the rotation of the motor becomes stable, the load detection by the motor current or the load detection by other means is started, and only in that case, the middle or low speed is immediately provided without providing a duration of 4 seconds. You may make it transfer to.

In this case, the sound is displayed by sounding means such as a buzzer sound several times, or by flashing the light emitting element to emit light, so that the load one second after the start of the high-speed driving is started. Displays a message indicating the start of detection,
The user can be reliably made aware of the start of detection.

Further, by providing the switch for confirming the automatic mode, the driving speed at which the user feels comfortable during execution of the automatic mode can be fixedly set. In addition, by providing a learning function of the operation content and starting from the driving content estimated to be optimal at the next driving, the operation is automatically started in the optimal mode and the usability is improved. In this case, the content of learning is estimated from the average load situation at the end of the previous operation and the elapsed time since then, and the current degree of beard growth is estimated, or the operator's usage tendency and speed selection tendency are determined. The content is not limited.

Furthermore, in the above-described embodiment, the average value of the motor current is used to determine the magnitude of the load. However, the present invention is not limited to this. Instead of or in addition to this detection method, the outer blade 14 is used. Alternatively, a sensor such as a pressure sensor or an optical sensor that can determine the contact between the skin surface and the outer blade 14 can be provided in the vicinity thereof. In this case, when the pressing force is directly detected or the darkness when the outer blade is pressed against the skin is detected, the operation is switched to the load detection based on the load current and the predetermined rotation speed control is performed. be able to.

In addition to the above-described determination method based on the load, a method for counting the number of pulse-like variations of the motor current generated during shaving is provided in addition to the above-described determination method based on the load. It can be more accurately grasped whether the object is simply pressed strongly against the skin surface.

Further, instead of changing the drive mode of the motor 17 to a circulating type in response to the pressing operation of the sub-switch 23, a slide type or a plurality of push button switches capable of directly selecting each mode are provided. For example, the mode selection method can be changed as appropriate.

Further, instead of changing the rotation speed of the motor 17 to three stages, it is also possible to change the rotation speed in four or more stages or steplessly. Even in such a case, it goes without saying that the above-described control states such as the increasing or decreasing tendency of the motor rotation speed are applied in substantially the same manner. Further, the first display unit 2
Similarly, the display at 1 is changed in accordance with the number of speed change stages that can be changed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram schematically showing a basic configuration of the present invention.

FIG. 2 is a partially cutaway front view showing an example in which the present invention is applied to an electric shaver.

FIG. 3 is an explanatory diagram illustrating a configuration of a fourth display unit.

FIG. 4 is a block diagram schematically showing an overall configuration of an electronic circuit.

FIG. 5 is an electric circuit diagram showing a configuration of a charge control unit.

FIG. 6 is a graph showing a change state of a terminal voltage of a secondary battery during charging and discharging.

FIG. 7 is an electric circuit diagram illustrating a configuration of a battery remaining amount detection unit.

FIG. 8 is an explanatory diagram showing display timing on a fourth display unit.

FIG. 9 is an electric circuit diagram showing a configuration of a motor control unit.

FIG. 10 is a waveform chart showing an example of a driving voltage applied to a motor.

FIG. 11 is a graph showing a relationship between a detection voltage and a comparison voltage in a motor control unit.

FIG. 12 is a transition diagram showing an operation mode of the electric shaver.

FIG. 13 is an explanatory diagram showing a procedure for changing the rotation speed of the motor, showing a case where the load application timing is short.

FIG. 14 is an explanatory diagram showing a procedure for changing the rotation speed of the motor, showing a case where a load application period is long.

FIG. 15 is an explanatory diagram showing a procedure for changing the rotation speed of the motor, and shows a case where switching between manual and automatic is used.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Battery 2 Main load 3 Operation means 4 Battery capacity detection means 5 Battery capacity display means 10 Electric razor 11 Main body case 12 Inner blade 14 Outer blade 17 Motor 18 Operation panel 19 Main switch 20 Light emitting element 21 First display unit 22 Second display Unit 23 Sub-switch 24 Third display unit 25 Fourth display unit 26 Charging adapter 31 Electronic circuit 32 Light emitting element 36 Secondary battery 37 Microcomputer device 38 Charging control unit 39 Battery remaining amount detecting unit 40 Motor control unit 41 Constant voltage circuit 42 No. 1 transistor 44 second transistor 45 light emitting element 46 third transistor 47 battery voltage detection unit 49 battery temperature detection circuit 50 comparison voltage generation circuit 51 battery voltage input circuit 52 booster circuit 53 switching circuit 54 low resistance 55 integration circuit 56 first comparison voltage Generation circuit 57 Second comparison voltage generation cycle 58 first switching circuit 59 the second switching circuit 60 a third switching circuit

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2G016 CB12 CB33 CC01 CC04 CC06 CC07 CC10 CC12 CC16 CC23 CC27 CC28 CD04 CD14 CE01 CE03 CE07 CE11 CF06 3C056 JD05 JD07 JD10 JD12 JD14 JD28 JD29 5G003 BA01 EA05 GC05 5H030 AA04 AS08 FF52

Claims (6)

[Claims] 1. A battery (1), a main load (2) to which drive power is supplied from the battery (1), and an operation means (3) for restricting on / off of an energization timing of the main load (2).
A battery capacity detecting means (4) for detecting the remaining capacity of the battery (1); and a battery capacity displaying means (5) for enabling a display corresponding to the current capacity of the battery (1). After a first set time T1 has elapsed since the power supply to the main load (2) was stopped, the battery capacity display means (5)
A small electric device which performs a display operation for a second set time T2. 2. The battery capacity detection means (4) performs a predetermined detection operation within the first set time T1, and displays a display corresponding to the remaining capacity detected in the detection operation. 2. The small electric device according to claim 1, wherein the means (5) performs the operation within the second set time T2. 3. The operation of detecting the remaining capacity, which is performed during the first time T1, is performed by estimating a return voltage from a rising tendency of a terminal voltage due to a stop of energization of the main load (2). Small electrical equipment. 4. The small electric device according to claim 2, wherein a display indicating that the detection operation is being performed is performed during the first set time T1. 5. The battery capacity detecting means (4) detects the battery capacity even when the main load (2) is energized, and displays a value corresponding to the battery capacity detected by the battery capacity display means (5). The small electric device according to claim 1, wherein: 6. The remaining capacity at the time when power supply to the main load (2) is stopped is stored, and the remaining capacity corresponding to the remaining capacity stored in the battery capacity display means (5) during the second set time T2 is stored. The small electric device according to claim 5, wherein the display is performed.