JPS592593A - Normal/reverse circuit for plural motors - Google Patents

Abstract

PURPOSE:To simplify the circuit configuration of a normal/reverse circuit for a plurality of motors by commonly using part of switching transistors to drive currents of the motors. CONSTITUTION:When a switch S11 is closed, a transistor T13 is conducted, switching transistors Q15, Q12 are driven to ON state, a drive current is flowed to the motor M1, which is normally rotaed. When a switch S12 is closed, a transistor T11 is conducted, switching transistors Q11, Q16 are turned ON, and the motor M1 is reversely rotated. Similarly, when the switch S13 is closed, a transistor T14 is conducted, transistors Q15, Q14 are turned ON, a motor M2 is normally rotated, and when a switch S14 is closed, a transistor T12 is conducted, transistors Q13, Q16 are turned ON, and the motor M2 is reversely rotated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a circuit for alternately rotating a plurality of motors forward and reverse.

FIG. 1 shows a switch circuit for reversing the rotation directions of two DC motors.

In this circuit, Q and ~Q8 are transformer NP type switching transistors for control, respectively, 02 * Q4 * Qa
, Q- are composed of NPN type switching transistors.

Now, when switch S2 is turned on, resistor r is connected to DC power supply E.
The transistor T1 becomes conductive through the switching transistor Q3.l'Y. Q2 is turned on.

Therefore, current flows through the motor M1 as shown by the dashed line A, and the motor M rotates in the forward direction.

Further, when the switch S2 is turned on, the transistor (2) becomes conductive, the switching transistors Q+ and Q4 are turned on, and current flows to the motor M1 as shown by the dashed line B, causing the motor M to rotate in reverse.

Similarly, regarding motor M2, when switch 33 is turned on, switching transistor Q7. When Q is turned on, the remoter M2 rotates forward, but when the switch S4 is turned on, the switching transistor QIl is turned on.

When Q6 is turned on, the remoter M rotates in the opposite direction.

However, this forward/reverse circuit is limited to the motor M+ to be controlled.
- When the number of Mt increases, the high-power switching transistors Q+ to Qa that drive the motors also increase by four times, and the protective diodes D to absorb spike voltages of the motors M, , M, and M.

~D8 also increases.

As a result, the circuit configuration becomes complicated, and when used in small electronic equipment, such as the operation mechanism of a tape recorder, downsizing is hindered due to space constraints, and the failure rate is also high.

The present invention has been made in view of this point, and provides a forward/reverse circuit for a plurality of motors in which some switching transistors are shared and the number of elements is reduced.

Hereinafter, the present invention will be explained with reference to the accompanying drawings.

Figure 2 is a σ circuit diagram when the forward/reverse circuit of this invention is implemented with two motor traps, Sll + SB is a switch for controlling motor M, and 313 + S + 4 is a switch for controlling motor M.
Switches Tll to TI4 for controlling the switching transistors Q7. ~Q+eY Transistor for on/off control % Dll-ova is a protection transistor that suppresses spike voltage. Note that EG is a constant voltage circuit that keeps the power supply voltage constant.

According to this circuit, when switches S, 'f are turned on,
A bias current flows from the DC power supply E through the resistor r3,
Transistor T,8 becomes conductive.

Therefore, the switching transistor QI5IQ+2 is driven to the on state, and the motor M
A drive current flows to the motor M, and the motor M rotates in the forward direction.

Also, switch SI2'! ? When it is turned on, the transistor 1°1. A bias current is supplied to
Transistor T11 becomes conductive, thereby switching transistor Q+++Q+. turns on.

Therefore, the dashed line B for Dota M, &C.

The drive current flows in the direction of the indicated force, and the motor M1 rotates in the reverse direction.

Similarly, when switch S3 is turned on, transistor TI
4 becomes conductive, and the switching transistors Q1. .

Q10 is turned on, the drive current shown by the dashed line A flows through the motor M, the motor M rotates forward, and the switch SI4'! When l' is turned on, the transistor Tu becomes conductive, the switching transistors Q+s and Q+a are turned on, and the drive current shown by the dashed-dotted line B2 flows.

Motor M will rotate in the opposite direction.

When compared with the circuit configuration of FIG. 1, it can be seen that since the switching transistors Q151Q16 are commonly used for motors M, , M, the number of elements is reduced accordingly and the circuit is simplified.

FIG. 3 shows another embodiment of the present invention, in which a study element 1 is substituted for the control transistors T++-T and 4 in FIG.
The case where 0 and 20Y are used is shown.

In this circuit as well, when the switches S, , yk are turned on, the switching transistors Q, 2 are turned on, and the output terminal of the logic element 20 is brought to a low potential, so that the switching transistors Q1, . turns on. Therefore, motor M1 rotates forward.

Further, when the switch S is turned on, the switching transistor Q++ is turned on, and the output of the logic element 10 becomes a high potential H, so that the switching transistor Q,
6 turns on and motor M1 reverses.

By similar circuit operation, the motor M2 can be rotated in the forward direction by turning on the switch S3, and can be made to rotate in the reverse direction by turning on the switch S4.

The case where the forward/reverse circuit of two motors M, , M, is implemented has been described above, but the embodiment shown in FIG.
This is a forward/reverse circuit implemented for two motors M+rMt*MIIIc.

In this circuit, S2+ + 522 is the motor M, and swing -1 which controls the forward and reverse rotation of the motor M.
2 forward/reverse switch, 52fi + sta
is a switch that controls forward and reverse rotation of the motor M3. In addition, the switching transistor Q271Ql is connected to each motor M.
,.

Commonly used in M21Ms, switching transistors Q21 I Q22 and Q2s r Q24 and Q25
* The bears of Q26 are motors M, , M, , M
The switching operation is performed for 3.

Furthermore, the logic elements 30 and 40 are negative logic OR circuits and NOR circuits that perform a three-person OR circuit compared to those shown in FIG.

This circuit is obtained by adding a switch S25 + 326 for controlling the motor M3 and a switching transistor Q25 + Q26 Y to the circuit shown in Fig. 3, and its forward/reverse control operation is as described above. ,
, M, , M are performed in the same way.

However, the conventional circuit configuration shown in Figure 1 requires 12 switching transistors to perform forward/reverse operation, but this circuit configuration can achieve this with 8 switching transistors, significantly reducing the number of elements. , and the circuit configuration becomes simple.

FIG. 5 is a block diagram showing yet another embodiment of the present invention, which is a preferred embodiment when the number of motors to be rotated forward and backward increases.

In this circuit, Q40 to Q40 represent switching elements,
Adjacent motors M, to M4 are configured to be commonly used. S40'' 34G indicates a control signal generator for turning on the pair of switching elements Q, -Q, indicated by dotted lines.

In this ladder type forward/reverse circuit, each motor M
It goes without saying that motors 1 to M4 can be rotated forward and reverse individually, but if the configuration is such that motors M1 to M4 of the same polarity are connected, each motor k can rotate forward (or reverse) at the same time.
'1° is also possible.

Further, since the current capacity of the switching element Q+o''Q+o only needs to be twice the motor drive current, this is advantageous when the number of motors to be rotated in the forward and backward directions increases.

Note that adjacent motors M1 to M4 simultaneously rotate forward and reverse.
Switch S40 * 543 so that there is no need to
*Alternatively, a circuit (logic circuit) for inhibiting simultaneous operation may be provided between 5421345, etc.

As explained above, the forward/reverse circuit for multiple motors of the present invention is configured so that a part of the switching transistor is commonly used for the drive current of each motor, so that a large capacity switching transistor (element), The number of elements such as protection diodes and the like can be reduced, and the mounting structure can be simplified accordingly. Therefore, the area dedicated to the circuit is reduced, and there are advantages in that it can be miniaturized and reliability is improved.

[Brief explanation of the drawing]

FIG. 1 is a forward/reverse circuit diagram of a conventional motor, and FIG. 2 is a diagram of a conventional motor. FIGS. 3 and 4 are forward/reverse circuit diagrams of a nuclear number motor showing an embodiment of the present invention, and FIG. 5 is a block diagram showing yet another embodiment of the invention. In the figure, Sll to S+t are switches for forward/reverse operation, 0+
+~Q+a*Q21~Q2M are switching transistors for supplying drive current, MI~M3 are motors, and E is a DC power supply 7.

Claims (1)

[Claims] A plurality of switching circuits consisting of two switching elements connected in series to a DC power source are provided, one terminal of the plurality of motors is commonly connected to one of the switching element connection points of the switching circuit, and the A forward/reverse circuit for a plurality of motors, characterized in that each of the other terminals of the motor is connected to another switching element connection point of the switching circuit.