JPS5847838Y2 - DC motor forward/reverse operation circuit - Google Patents

Description

[Detailed description of the invention] This invention relates to a forward/reverse circuit for a DC motor, particularly a permanent magnet excitation type DC motor, and its purpose is to perform forward/reverse operation by minimizing the number of contacts such as operation switches. It is.

FIG. 1, FIG. 2, FIG. 3, and FIG. 4 show conventional forward/reverse operation circuits, and the circuit configuration and problems will be sequentially explained below.

FIG. 1 shows a circuit that performs forward and reverse operation using only a forward and reverse operation switch.

Terminals 1 and 2 are connected to either the positive or negative terminal of a DC power source.

SW is a forward/reverse operation switch with central OFF;
When it is tilted to the side, it rotates in the forward direction, and when it is tilted to the R side, it rotates in the reverse direction.

In this method, the circuit configuration is simple, but the operating switch requires two circuits and two contacts with a central OFF switch, for a total of four contacts, and a complex switch is required, especially the operating switch. This may cause inconvenience when the device is required to be small.

Figure 2 shows another conventional example that is almost the same as Figure 1, and the operation switches are a forward rotation switch SWF and a reverse rotation switch S.
It is divided into two circuits: WR.

In this configuration, the switch is a simple operation switch with one set of normally open contacts and one set of normally closed contacts, and has the advantage of not requiring a central OFF function, but it requires two operation switches, and Moreover, there is a problem in that the mounting position is restricted.

In addition, in this configuration, when both operation switches are turned to the operation side, the electric motor is not operated.

In FIG. 3, two relays RY1 and RY2 are used to simplify the configuration of the operation switch.

When the operation switch SW for forward/reverse operation is turned to the forward rotation side, relay R is activated.
The coil of Y1 is energized, and the contacts RY, , and RYl,
, closes, and the motor rotates in the forward direction.

In addition, in the case of the reverse side, relay RY2 works and contact RY2-
1 and RY2-2 close, reversing the motor.

In this configuration, the operating switch is one with a central OFF switch.
A two-contact circuit often simplifies the circuit, but requires two relays, and each relay requires two sets of normally open contacts, making the whole circuit complex and often uneconomical.

FIG. 4 is a modification of FIG. 3, and the operating switches are the same, but the connection configuration of the relay contacts is different and simpler.

Each relay only needs to have one set of normally open contacts and one set of normally closed contacts, and although the relay is simpler than the example in Figure 3, the point is that two relays are used, It can be said that it is complicated and uneconomical.

The present invention solves the above-mentioned conventional drawbacks, and one embodiment of the present invention is shown in FIG.

In FIG. 5, terminals 1 and 2 are terminals connected to a DC power source.

The normally open contact side of the first contact RY-1 of the relay RY and the common terminal of the forward/reverse operation switch SW are connected to the terminal 1, and the terminal 2 is connected to the normally open contact side of the first contact RY-1 of the relay RY.
The normally closed contact side of the relay RY is connected to one side terminal of the second contact RY-2 (normally open contact) and one side terminal of the coil of the relay RY.

The common terminal of the first contact RY-1 of the relay RY is connected to one side of the motor M, and the other terminal of the second normally open contact RY-2 of the relay RY and the reverse side contact R of the operation switch SW.
are shared and connected to other terminals of the motor M.

In addition, the normal rotation side contact F of the operation switch SW and the relay RY
The other terminals of the coil are connected.

Next, the operation will be explained.

The operation switch SW is a switch with a center OFF switch, and when it is turned to the normal rotation side, the contact F side becomes conductive and the coil of the relay RY is energized, and the first contact RY-1, the normally open contact, and the second normally open contact, RY. -2 is closed, a voltage of a certain polarity is applied to the motor M, and the motor M rotates in the forward direction.

Next, once the operation switch SW is turned OFF and turned to the reverse side, the contact R side becomes conductive. At this time, the coil of the relay RY is not excited, so the normally closed contact of the first contact RY-, is conductive. A voltage in the opposite direction is applied to the electric motor M, causing it to rotate in the reverse direction.

Note that in this description, the meanings of forward rotation and reverse rotation only indicate a relative difference in direction, and do not indicate a certain fixed direction.

FIG. 6 is a circuit diagram showing another embodiment of the present invention, and since the operation is exactly the same except for the way in which the common terminal of the relay contact is arranged, detailed explanation will be omitted.

In addition, in Figures 5 and 6, terminal A is one side terminal of the first normally open contact of relay RY, and the terminal opening is relay R.
This is one side terminal of the normally closed contact of Y, and terminal C is the terminal of relay RY.
The other terminal of the first normally open contact of relay RY
Terminal 2 is the other terminal of the normally closed contact of relay RY, terminal E is one side terminal of the second normally open contact of relay RY, and terminal E is the other terminal of the normally closed contact of relay RY.
It can be said that this is the other terminal of the second normally open contact.

According to this invention, the operation switch for forward and reverse rotation is centrally OFF.
It is very easy to use with the attached 1 circuit 2 contact operation switch,
Since only one relay is added, it is simpler and more economical than the conventional example, and is particularly effective when there are restrictions on the number of operation switches.

[Brief explanation of drawings]

Figures 1, 2, 3, and 4 are circuit diagrams for forward and reverse operation of a conventional DC motor, Figure 5 is a circuit diagram showing an embodiment of the present invention, and Figure 6 is a circuit diagram of the present invention. FIG. 3 is a circuit diagram showing another embodiment of the invention. 1.2...Power connection terminal, SW...Forward/reverse operation switch, M...DC motor, RY
...Relay, RY-1...First contact, RY-2...Second contact, A...First normally open contact One side terminal, opening: One side terminal of normally closed contact, C: other terminal of first normally open contact, other terminal of normally closed contact, 2: second terminal One side terminal of the normally open contact, E... the other terminal of the second normally open contact.

Claims (1)

[Scope of utility model registration request] One terminal of the first normally open contact of the relay and a common terminal of the forward/reverse operation switch are connected to one terminal of the DC power supply, and one terminal of the normally closed contact of the relay and the common terminal of the forward/reverse operation switch are connected to the other terminal of the DC power supply. One side terminal of the second normally open contact and one side terminal of the coil of the relay are connected, and the other terminal of the first normally open contact of the relay and the other terminal of the normally closed contact of the relay are connected in common to the DC motor. The other terminal of the second normally open contact of the relay and one side contact of the forward/reverse operation switch are commonly connected to the other terminal of the DC motor, and the forward/reverse operation switch is connected to the other terminal of the DC motor. A forward/reverse operation circuit for a DC motor in which the other side contact of the relay is connected to the other terminal of the coil of the relay.