JPS59222092A - Energization control circuit - Google Patents

Abstract

PURPOSE:To reduce a leakage current by connecting a control transistor to the base of a main switch transistor and connecting a PUT to the base of a control transistor. CONSTITUTION:Switches S1, S2 are normally in nonconductive state, and since a programmable unijunction transistor PUT is in nonconductive state, a control transistor Q2 and hence a main switch transistor Q1 is in nonconductive state. When the switch S1 becomes conductive, a gate current is flowed to the PUT, the PUT is conducted, the transistor Q2 and hence the transistor Q1 becomes conductive to flow a drive current to motor M. When the switch S2 is made on with the switch S1 being conducted, the PUT becomes nonconductive, and the transistor Q2 and the transistor Q1 become nonconductive, thereby stopping the supply of the current to the motor M.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a small electric appliance such as an electric shaver that is equipped with a battery as a power source, and relates to a drive control circuit for the motor thereof.

(B) Prior Art In conventional motor drive circuits for small electric appliances, particularly electric shavers, the motor and power source are usually connected in series via a mechanical switch. Most of the mechanical switches used in these devices were so-called slide switches whose contacts were coated with Ag to reduce contact resistance.

However, this type of motor drive circuit has the drawbacks of a large leakage current, large variations in contact resistance due to mass production of the slide switch itself, and instability of motor drive control due to this switch.

(c) Purpose of the Invention The present invention has been made in view of the problems of the prior art as described above, and provides a load energization control circuit that reduces leakage current and is stable against variations in contact resistance of switches. The purpose is to provide

(-, l A small current of the invention's dissipation number mA or less is used as a current, and h is applied to the load operating circuit that amplifies the current and supplies the current to the load. The current circuits are connected in 100 rows, and the base of the transistor Q1 is controlled (
1141, and the gate of the transistor Q2 is connected to the anode of the programmable unijunction transistor PUT.
When the transistor PUT is conductive, the transistor Q1
, Q2 are both conductive to supply current to the load, and the piezoelectric current control circuit of the programmable unijunction transition system PUT is configured as follows: can.

B-) Embodiment FIG. 1 shows a power tracing control circuit using a motor as a load, which constitutes the main part of the present invention. The motor) is connected to a direct current power supply (DC) of less than mA to form a drive circuit CMC) for the motor. (Ql) is the motor written in OfJ (M
The main switch transistor is an NPN type main switch transistor whose collector is connected to one end of the transistor and whose main current circuit is directly connected to the drive circuit (MC), and when it is conductive, a current of several tens of amperes flows.

(Q2) is a control transistor whose collector is connected to the base of the transistor (Ql), and whose emitter is connected in parallel to the drive circuit (MC) via a resistor (I<7).

(PUT)id is a programmable unijunction transistor, and its anode (3) is connected to the base of the control transistor (Q2), and the drive circuit WJ (MC) is connected to the control transistor (Q2) via a resistor (R5).
), and the anode (At) is also connected to the resistor (R4
) is connected to the drive circuit (MC) K through the programmable unijunction transistor (PU
The main current circuit of T) is connected in parallel to the drive circuit (MC). The gate (G) of the programmable pull unijunction transistor (PUT) is connected to the intermediate potential point (Pi)Ic between the resistors (R1) and (R2), and the intermediate potential point (Pl) and the resistor (R2) are connected to each other. A touch-on switch (Sl) is connected in series between the two. Further, a touch-off switch (S2) is connected to the intermediate potential point (Pl) in parallel with the resistor (R1). Also resistance (R
] is a sensitivity adjustment resistor connected between the gate (Gl) and the anode fA1 of the transistor (PUT).

As shown in FIG. 1, a tanthione switch (Sl)
When 1a becomes conductive, the programmable union transistor (PUT) K gate current (ig)
flows, the transistor (PUT) becomes conductive, and a current (13) flows through its main current circuit. Therefore, the voltage at the anode (iA) of the Hilt transistor (PUT) decreases,
The base voltage of the control VII transistor (Q2) decreases, and the base voltage /jBib) flows, and the transistor (Q2) flows.
2) is a shame, the main switch transistor (Ql)
A base current (ic) flows through the transistor (Ql).
conducts, and the morph drive current (
im) flows and the morph prisoner) is driven. Note that a low saturation transistor is used as the main switch transistor (Ql) to minimize the voltage drop at the transistor (Ql).

Note that the low saturation transistor referred to here is the characteristic curve of the emitter converter quadruple 1 king (EECJ and coretough current CIC) of the transistor shown in Figure 2. The rising slope (θ) of the current in the low voltage section shown in green A device designed to be small.

Normally, both touch switches (Sl) (s2) are in a non-conducting state, and the control transistor (Q2) l-j
:, unless the programmable pull unijunction transistor (PUT) is passed through 4, the transistor (Q2
) are connected in a non-conducting direction, and the impedance between the gate (Gl-l anode 1) of the transistor (PUT) is greater than #:, MΩ, so that almost no leakage current occurs.

When the switching switch (S2) is turned on while the switching switch (sl) is conducting, the anode (A) and cathode K) of the programmable pull unijunction transistor (PUT) become the same potential, and the gate current increases. (Ig) stops flowing and the transistor (PUT
) becomes non-conductive.

Immediately, both the control transistor (C2) and the main switch transistor (Q'l) become non-conductive, and the supply of current to the motor (2) is stopped.

Figure 6 shows 1.5■ rechargeable electricity/It! ,tB! This is the first application example where motor K is connected in series. In this circuit, in addition to the main control circuit shown in FIG. 1, the programmable unijunction transistor (PUT)
) is equipped with a noise prevention capacitor (C1) between the gate tG) and the anode (A1, and the secondary coil of the step-down transformer σ) is connected to the commercial alternating current power supply (AC) and the second filter. It is connected to the rectifying diode (Dl).

The operation of the noise prevention capacitor (C1) is in accordance with the well-known technology, and the operation of the other circuit components is also in the same manner as described above, so a description thereof will be omitted here.

Figure 4 shows a further development of the present invention as a motor drive circuit for an electric shaver. ) Equipped with the motor! M
1, Schottky diodes (B5) (B4) are connected in series (LO), and Schottky diode (DLO) is connected to -
(ME) in series and connected to E (I) without connecting a Schottky diode, the drive speed of the motor (Ml) can be switched in six steps.Also, the rechargeable battery (B
1) Connect the midpoint (B2) of (B2) and one end of the secondary coil of transformer α゛), and connect the rectifier diode (Dl) (B
2) is used to supply the aftereffect rectification to the battery (Bl) (B2). Further, a light emitting diode (LED) is connected across the connection point (B6) between the diodes (DI) and (B2) and the cathode (K) of the programmable unijunction transistor (PUT).

The operation during discharging of the battery (Bl)CB2) is the same as the circuit operation 91V shown in FIG. 1 described above, and therefore will not be described here.

When charging the batteries CB1) and CB2), the transformer σ)
When connected to a commercial alternating current power source (AC), the battery (B1
) is charged by the current (iDl) through the diode (Dl), and the battery (B2) is charged by the current (iD2) through the diode (B2). At this time, a current flows from the connection contact (P) to the cathode () of the programmable unijunction transistor (PUT), and the light emitting diode (LED) lights up.By the way, the light emitting diode (LED) is conductive. Inside is the programmable unijunction transistor (PUT).
) rises in potential at the cathode (Kl) of the transistor (
PUT) is not conductive. Therefore, the touch-on switch (S
l) and the touch-off switch (B2) malfunctioned, causing the dog to =! Even if the battery is disconnected or disconnected, the motor (temporary) will not be driven during charging.

The negative 'S5 diagram is a q-fold diagram of a suitable off-switch arrangement. (Sl) is the only ON switch that drives the motor α1) (B2), and the gate (G) of the programmable unijunction transistor (PUT) ~
Switches (B6) and (B4) connected across the anode (A1 and between the anode (N and cathode) are all off switches for stopping the drive of the motor [M]. In particular, switch (B2) (B3) l-1: conducts only when pressed, and then becomes non-four-way. By applying a reverse voltage to the gate (Gl), the main current of the transistor (PUT) is cut off by applying a reverse voltage to the gate (Gl) by making the switch (B2) or (B6) conductive. The switch (B4) connects the anode (
The main current of the transistor (PUT) is cut off by shorting between A) and the cathode (K1).
At the time when the switch (B4) is turned on, the motor 1) is still being driven, and unless the switch (B4) is turned off, the motor will not stop driving.

Also, in the case of this switch (B4), the transistor (PU
Since the main current flowing through T) is canted by 1μ, contact failure is likely to occur. On the other hand switch (B2) or (B6
) can be made conductive, the transistor (PUT) can be made non-conductive immediately, and the response time can be shortened. Therefore, a two-off switch (S2) connected as an off switch as shown in FIG. 1 or FIG. 6.4 is most effective. Moreover, this touch-off switch (S
2) has good contact durability because it only interrupts a small current.

As explained above, in a load operating circuit that uses a small current of several mA or less as a power source, amplifies it, and supplies current to the load, the main switch is used for the load. The main current circuit of the transistor Q1 is connected in series, the base of the transistor Q1 is connected to the collector of the control transistor Q2, and the base of the transistor Q2 is connected to both the transistors Q1 and Q2 when the programmable unijunction transistor PUT is turned on. Since there are four books and the power is supplied to the load, it is possible to provide an innovative device using a touch switch in place of the slide switch or bush switch that has been mainly used in conventional small electric devices. Moreover, since the current flowing to the load is controlled by the conduction/non-conduction of the programmable unijunction transistor, the leakage current when the transistor is non-conductive is small, and it is also effective in compensating for variations in the contact resistance of the +J touch switch. This makes it an optimal load energization control circuit for small electric devices, especially battery-applied devices that use a small current as a power source.

[Brief explanation of the drawing]

Fig. 1 id: Circuit diagram of the main part of the present invention, Fig. 2 is a characteristic diagram of a low saturation transistor, Fig. 6 is a circuit diagram of a morph drive circuit using a rechargeable battery, and Fig. 4 is a circuit diagram of a morph drive circuit using a rechargeable battery. A circuit diagram applied to a power supply driving circuit for a razor, and FIG. 5 is a circuit diagram considering the arrangement of switches. (Bl...@source, N)...Motor (load 9, (MC
)...Operating circuit, (Ql)...Main switch transistor, (Q2)...Control transistor, (P
UT)...Programmable unijunction transistor. Applicant: Sanyo Electric Co., Ltd., Patent Attorney, Shizuka Sano Inue” Procedural Amendment (spontaneous) September 27, 1980 To the Commissioner of the Japan Patent Office 1, Indication of Case Patent Application No. 97256, 1982, 2, Name of the invention: energization control circuit, relationship with the case of the person making the amendment Patent applicant name (18B) Sanyo Electric Co., Ltd. 4, agent address 2-18-5 Keihan Hondori, Moriguchi City, details subject to amendment A column for a detailed description of the invention in the book. 66 Details of the amendment @ Page 6, lines 15 to 20, it is stated that ``When the touch-on switch (S) is turned on... (P
IJf) becomes non-conductive. "When the touch-off switch (S2) is turned on, the gate voltage of the programmable unijunction transistor (PUR) becomes high, so the transistor (PUT) becomes non-conduction. ” he corrected.

Claims (1)

[Claims] 11) In a load drive circuit that uses a small current of several mA or less as a power source and amplifies it to supply current to the load, the main current circuit of the main switch transistor Q1 is connected to the load. are connected in series, the base of the transistor Q1 is connected to the collector of the control transistor Q2, and the base of the transistor Q2 is connected to the anode of the programmable unijunction transistor pu'r. 11. An energization control circuit characterized in that transistors 1 and Q2 of gfJ are both made conductive and energized to a load of 11f. 12) The energization control circuit according to claim 1, wherein the load is connected to the flexible switch transistor Q1.