JPH0316605Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an electric shaver, particularly one that controls the rotational speed of a motor.

[Conventional technology]

It is generally known that the so-called "good cross section number ratio" when shaving using an electric razor shows a peak value at a constant motor rotation speed. In other words, there is an ideal motor rotation speed for cutting beards, and if the speed is faster or slower than this speed, good beard cutting will not be possible.

In response to this knowledge, the present applicant proposed an electric shaver that constantly detects the rotational speed of the motor and maintains the speed of the motor constant regardless of the light or heavy load (Patent Application No. 1983- No. 184930).

[Problem that the invention attempts to solve]

By the way, the relationship between the motor rotational speed and the number ratio of good cross sections is established only on the premise that the motor rotational speed and the relative speed of the inner and outer cutters have a one-to-one correspondence. However, in reality, energy loss or mechanical rattling due to the transmission means interposed between the motor and the inner cutter is unavoidable, and due to such losses, the motor rotational speed and the relative speed of the inner and outer cutters do not necessarily match. . Furthermore, in electric shavers, as a result of the frequent application and release of loads,
Load fluctuations during use of the device are particularly significant compared to other electrical devices, and there is a risk that appropriate control may not be performed.

The present invention was developed in view of the above problem, and is designed to operate reliably and maintain a constant relative speed between the inner cutter and the outer cutter regardless of transmission loss in the driving force transmission means or rapid changes in load. It is an object of the present invention to provide an electric shaver that can be used in an optimal state at all times and that operates reliably without being affected by hair debris.

[Means for solving problems]

The schematic diagram shown in FIG. 1 shows the basic configuration for achieving the above object, and includes an outer cutter 12,
An inner cutter 14 inscribed in the outer cutter 12, a driving force transmitting means 18 that supports the inner cutter 14 and transmits the driving force of the motor 17 to the inner cutter 14, and has the same function as the inner cutter 14. Means 3 for detecting the driving state of the blade 14
1, a motor 17, means 31 for detecting the transition speed of the driving force transmission means 18, and a circuit 19 for controlling the rotational speed of the motor 17.

For example, if the inner cutter 14 is a reciprocating type, the driving force transmitting means 18 converts the rotational force of the motor 17 into reciprocating power, and if the inner cutter 14 is a rotary type, transmits the rotation as it is to the inner cutter 14 as a coupling.

The control circuit 19 compares the value of the detection signal 36 output from the detection means 31 with the value of the reference signal 40, and if a deviation occurs between the two, adjusts the voltage applied to the motor 17. motor 1
7, and thus the relative speed between the inner cutter 14 and the outer cutter 12, is maintained constant.

In the present invention, the detection means 31 is composed of a photocoupler, the detection signal 36 is extracted not from the motor 17 side but from the driving force transmission means 18 side, and the detection position is separated from the outside and the hair collection chamber 15. Features. That is, a shielding chamber 16 is provided that covers at least a portion of the driving force transmitting means 18 and is separated from the outside and the hair collection chamber 15, and a speed detecting means is provided at the moving position of the driving force transmitting means 18 within the shielding chamber 16. 31 makes it possible to extract a detection signal 36 proportional to the relative speed of the inner and outer cutters 14 and 12 and input it to the control circuit 19.

[Effect]

When the control circuit 19 is energized in the above configuration,
A driving voltage 38 is applied from the control circuit 19 to the motor 17, and the rotation of the motor 17 is caused by the driving force transmitting means 1.
8 to the inner cutter 14, and the inner cutter 14 internally slides against the outer cutter 12. The reciprocating speed of the inner cutter 14 is detected by the inner cutter speed detection means 31, and the extracted detection signal 36 is compared with a reference signal 40 in the control circuit 19 and both signals 36 and 4 are detected.
The voltage applied to the motor 17 is increased until the values of 0 match, and the rotational speed of the motor 17 is maintained at the set value.

When shaving is performed here and a sudden increase in the load on the inner cutter 14 occurs, the moving speed of the inner cutter 14 tends to decrease due to this increase in load, but inside the shielding chamber 16 near the inner cutter 14 The detection means 31 installed in a part of the driving force transmitting means 18 which supports the inner cutter 14 and has the same function as the inner cutter 14 detects the influence of rattling etc. that occurs between the motor 17 and the driving force transmitting means 18. Inner blade 1
4 speed changes are accurately detected. Further, an abnormality in the inner cutter reciprocating speed acts in the direction of increasing the drive voltage in the control circuit 19, increasing the rotational speed of the motor 17, and correcting the relative speed of the inner cutter 14 with respect to the outer cutter 12 as quickly as possible. Moreover, even transient speed fluctuations are to be avoided.

〔Example〕

The present invention will be specifically explained below based on an example implemented in a reciprocating electric shaver 11 shown in FIGS. 2 to 5, but it goes without saying that it can be similarly applied to various types of electric shavers such as rotary electric shavers.

The electric shaver 11 embodying the present invention has an outer cutter 12 detachably attached to the upper part of the main body case 13, as in the conventional case, and an inner cutter 14 is inserted into the hair collection chamber 15 inside the outer cutter 12. Place it so that it can move freely. Furthermore, inside the main body case 13, a motor 17 for reciprocating the inner cutter 14 via a driving force transmission means 18, a circuit 19 for controlling the moving speed of the inner cutter 14, and a circuit for driving the motor 17 and the control circuit 19 are provided. In addition to housing the battery 20, the main body case 13
A switch 21 for regulating the timing of energization to the control circuit 19 is disposed in front of the control circuit 19.

The driving force transmission means 18 includes a reciprocating plate 2 having a substantially rectangular plate shape.
By extending substantially U-shaped hanging portions 23 from both ends of the reciprocating plate 22 and fixing both ends 24 to the upper wall 25, the reciprocating plate 22 can be freely reciprocated left and right as shown by the dashed line. . Furthermore, reciprocating plate 2
A support rod 26 is provided protruding from the upper surface side of the support rod 2.
While the inner cutter 14 is attached to the tip of the reciprocating plate 22, a guide groove 27 is provided at the center of the lower surface of the reciprocating plate 22, and the motor 17
By inserting an eccentric pin 30 fixed to the rotating shaft 29 of the motor, the inner cutter 14 is caused to reciprocate and slide relative to the outer cutter 12 in conjunction with the rotation of the motor rotating shaft 29.

In the present invention, a portion of the main body case 13 where the driving force transmission means 18 is located is partitioned to provide a shielding chamber 16 separated from the outside and the hair collection chamber 15, and the driving force is transmitted inside the shielding chamber 16. A feature is that a speed detection means 31 for the inner cutter 14 is disposed near the means 18. The speed detection means 31 is
Light emitting diode 32 and phototransistor 3
3, and by arranging the optical path 35 of the light emitting diode 32 across the reciprocating path of the lower end 34 of the hanging part 23, the reciprocating movement of the reciprocating plate 22, and thus the inner cutter 14, is The optical path 35 of the light emitting diode 32 is intermittent at the lower end 34 of the lower part 23, and a detection signal 36 of a pulse rate proportional to the reciprocating speed of the inner cutter 14 is generated without being disturbed by external light or hair.
can be reliably removed. The detection signal 36 taken out from the speed detection means 31 is sent to the control circuit 1
9 and is used to control the rotational speed of the motor 17.

The control circuit 19 includes an inner blade speed detection section 39 that converts the pulse-like detection signal 36 taken out from the phototransistor 33 into a detection voltage 37 having a voltage value proportional to the pulse rate, and a value of the detection voltage 37 and a reference voltage. 40 and applies a drive voltage 38 to the motor 17 corresponding to the difference between the two.

The inner blade speed detection section 39 includes a phototransistor 3
Detection signal 36 detected in 3 and set voltage 43
After adjusting the level of the detection signal 36 to a predetermined value by taking the difference between the
By integrating with the OP amplifier 45, a detection voltage 37 with a value proportional to the pulse rate of the detection signal 36 is generated.
can be output to the comparison section 42.

The comparison section 42 compares the reference voltage 40 output from the reference signal generation section 46 and the detection voltage 37 described above.
An OP amplifier 47 compares the two voltages, and a control voltage 41 corresponding to the difference between the two voltages output from the amplifier 47 regulates the voltage drop between the collectors and emitters of the transistors 49 and 50, and controls the drive voltage 38 applied to the motor 17. Automatically adjust.

The reference signal generator 46 includes a constant voltage diode 51
The Zener voltage is divided by a variable resistor 52, stabilized by a large-capacity capacitor 53, and then inputted to one end of an OP amplifier 47 via an integrating circuit 54. With this configuration, the reference voltage 40 is gradually increased to reach the set voltage immediately after the switch 21 is turned on, and therefore the motor 17 is not affected by transient high voltages due to the slow motor rotation speed and low detection voltage at the initial startup stage. This prevents voltage from being applied.
Note that the on/off states of the transistors 55 and 56 are reversed at the same time as the switch 21 is turned off, and the capacitor 53 is short-circuited between the emitter and collector of the turned-on transistor 56 to instantly discharge the charge and return to the initial state. The above operation can be performed reliably even if the switch is turned on and off frequently. Further, by appropriately setting the value of the capacitor 57 of the integrating circuit 54, control adapted to the starting characteristics of the drive system including the inner cutter block 15 and the motor 17 can be performed.

Furthermore, if the control circuit 19 does not perform control proportional to the pulse rate of the detection signal 36, but performs rotation speed control proportional to the pulse width, not only the rotation speed of the motor 17 will decrease, but also problems caused by hair clogging, etc. A decrease in speed due to a decrease in the reciprocating stroke of the inner cutter 14 can also be detected and controlled. Furthermore, instead of converting the detection signal 36 into a voltage value and comparing it with the reference signal 40, it is also possible to compare the frequency of the detection signal 36, for example, as a numerical value.

Furthermore, in the case of rotary electric shavers,
If the shaft of the inner cutter holder constituting the driving force transmission means 18 is disposed within the shielding chamber 16 and the rotation of the shaft is detected by a photocoupler by reflecting or blocking light, substantially the same control as described above becomes possible.

[Effect of idea]

As described above, the present invention is designed to control the rotational speed of the motor 17 by detecting the transition speed of the driving force transmitting means 18, which supports the inner cutter 14 and has the same function as the inner cutter 14. The motor 17 and the driving force transmitting means 18 are different from those that detect the rotational speed of the motor 17 and the movement of the moving case due to the pressing force of the skin as described in Japanese Utility Model Publication No. 53-25666. The relative speed between the inner and outer cutters 14 and 12 is accurately detected without being affected by rattling between the inner and outer cutters 14 and the moving case, and appropriate rotational speed control of the motor 17 can be performed.

Further, at least a portion of the driving force transmitting means 18 is disposed in the hair collection chamber 15 and the shielding chamber 16 separated from external light, and a photocoupler is used as the detecting means 31 to determine the transition speed of the driving force transmitting means 18. By detecting
It has the advantage of being able to perform reliable detection and control of the operation.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram showing the basic configuration of the present invention;
The figure is a perspective view of an electric shaver implementing the present invention, Figure 3 is an enlarged sectional view of the main parts, Figure 4 is an exploded perspective view,
FIG. 5 is an electrical circuit diagram of the control circuit. 12... Outer blade, 14... Inner cutter, 15... Hair collection chamber, 16... Shielding chamber, 17... Motor, 18
...Driving force transmission means, 19...Control circuit, 31...
...Speed detection means, 36...Detection signal, 40...Reference signal.

Claims (1)

[Scope of Claim for Utility Model Registration] An outer cutter 12, an inner cutter 14 that slides inwardly on the outer cutter 12 in a hair collection chamber 15 inside the outer cutter 12, and a motor 17 that drives the inner cutter 14. , a driving force transmitting means 18 that supports the inner cutter 14 and transmits the driving force of the motor 17 to the inner cutter 14 and moves in the same manner as the inner cutter 14; and a photocoupler that detects the transition speed of the driving force transmitting means 18. and a circuit 19 that compares the detection signal 36 outputted from the detection means 31 with a reference signal 40 and controls the rotational speed of the motor 17 in accordance with the difference between the two. A shielding chamber 1 in which at least a portion of the driving force transmitting means 18 and the detecting means 31 disposed close to the driving force transmitting means 18 are isolated from the outside and the hair collection chamber 15.
An electric shaver characterized in that the electric shaver is arranged in