JPH0214765B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention is applicable to cases where a switch for operating an automobile's power window, sunroof, auto antenna, etc. is self-maintained in the operating position, or when a circuit is to be protected against overcurrent or overvoltage. This relates to electromagnets used in applications such as electromagnets.

Conventionally, relays or plungers were used to keep the circuit energized, electromagnets were used to attract iron pieces, etc., and electronic circuits or relays were used to detect overvoltage or overcurrent and cut off the current. It was done.

For example, one touch a car's power window,
In other words, when a single instantaneous switch ON is used to fully open or fully close the switch, the relay detects the switch ON and continues supplying power to the motor, and the window finishes opening/closing, locks the motor, and prevents overcurrent. This required an electronic circuit for overcurrent detection that senses the current and shuts off the relay.

Therefore, it has disadvantages such as an increase in installation space and an increase in cost due to the use of electronic circuits, relays, etc.

An object of the present invention is to eliminate the drawbacks of the conventional method, and to perform a desired operation by attracting a first movable member by energizing a single coil, and when the current flowing through the coil exceeds a certain value. Turn on the switch associated with the second movable member that is attracted by the leakage magnetic flux.
The coil is turned off to cut off the current to the coil and stop the operation of the first movable member, such as self-holding, so that one coil performs two operations: the required operation and over-electrode detection. In this way, the installation volume is reduced, and the cost is reduced by reducing the number of electrical circuits.

Now, an embodiment of the present invention will be described with reference to FIGS. 1 and 2. A coil 4 is wound around a yoke 1 and a bobbin 3 attached to a yoke 2 fixed to the yoke 1. Insert the core 5, which is the first movable member, so that the suction part 5a is located inside.
When the core 5 is moved to the right or left by an external force and a current flows through the coil 4, the suction portion 5a of the core 5 is suctioned and held by the yoke 1 or 2 and performs the required operation.

A notch 1a is provided in the yoke 1 to make it easier for the leakage magnetic flux of the yoke 1 to concentrate in this part, and an armature 7, which is a second movable member, is attached to one side of the yoke 1 via a leaf spring 6, and a movable contact 8 is attached to the armature 7. A contact spring 9 having a fixed terminal 10 is fixed, and a fixed contact 11 of a fixed terminal 10 is installed opposite the movable contact 8.

Therefore, while the normal current is flowing through the coil 4, the core 5 is attracted, but the armature 7 is not attracted to the yoke 1 due to the force of the leaf spring 6.
When an overcurrent exceeding a certain level flows through the coil 4, the leakage magnetic flux of the yokes 1 and 2 increases, and the leakage magnetic flux is particularly noticeable in the notch 1a, and in order to attract the armature 7, the movable contact 8 moves to the fixed contact 11
Since the coil 4 and the movable contact 8 are connected in series, the current to the coil 4 is cut off.

Therefore, the attraction of the core 5 to the attraction part 5a is also eliminated, and the core 5 returns to its original state by the force of the arms, springs, etc. that are in contact with it.

Next, referring to the embodiment shown in FIGS. 3 and 4, a coil 4 is wound around a bobbin 3 supported by yokes 1 and 2, and a spring 12 is installed between the bobbin 3 and the bobbin 3. The core 5 is inserted through the suspended core 5.
screw the rod 13 into the core 5.
The structure and operation of the plate spring 6 to the fixed contact 11 are the same as in the previous embodiment.

Another embodiment will be described with reference to FIGS. 5 and 6. A yoke 1 having a bobbin 3 around which a coil 4 is wound is biased upwardly by a spring 14 at one end of the yoke 1 to move the first movable member. Attach the barrel armature 15 to the hinges,
When a current flows through the coil 4, the armature 15 is attracted and held and the state is transmitted through the rod 13, and the armature 15 is provided with a notch 15a, in which the leaf spring 6 or the fixed contact 11 are provided. This embodiment is the same as the first embodiment, and its operation is also the same as the first embodiment.

Further, the fourth embodiment will be explained with reference to FIGS. 7 and 8. In place of the spring 14 of the previous embodiment, a tension spring 1 is used.
6, and in place of the notch 15a of the armature 15, a notch 1a is provided in the yoke 1, and the leaf spring 6 is inserted into the notch 1a.
The fixed contacts 11 are installed, and the operation of each part is the same as in the previous embodiment.

The case where these devices are implemented in a one-touch type power window will be explained with reference to Fig. 9.
A switch 20 having contacts of circuits A and B is connected to the coil 4 via a motor 21 for opening and closing the window, the fixed contact 11 of each of the above embodiments, and the movable contact 8, and when circuit A is closed, the window is closed. If circuit B is closed, the motor 21 will rotate in the direction in which the window opens;
Or, when B is closed, it is locked in that state, and the core 5 of the first and second embodiments and the armature 15 of the third and fourth embodiments are connected to the rod 1 when the coil 4 is de-energized.
3, the locking is released.

Therefore, if circuit A of switch 20 is now closed, the current from battery 22 will flow through circuit A of switch 20.
- Motor 21 - Circuit B of switch 20 - Fixed contact 11 - Movable contact 8 - Coil 4 flow in this order and the window moves in the closing direction, but since switch 20 has the locking mechanism as described above, circuit A is ON. The state continues until the window is completely closed.

However, when the window finishes closing, the motor 21 becomes locked, so the current value increases and an overcurrent also flows to the coil 4, which pulls the armature 7, which is the second movable member, and moves the movable contact 8 from the fixed contact 11. When the switch 20 is separated, the circuit is cut off and current no longer flows to the motor 21, and the lock of the circuit A of the switch 20 is released via the rod 13.
The switch 20 returns to its original position, and the switch 20
The power windows can be opened and closed with a single touch.

Furthermore, as shown in FIG. 10, by connecting the devices of the first to fourth embodiments in parallel with the load Z, a protection circuit against overvoltage can be formed, and the ON state of switch C is the same as that of each embodiment. It is controlled by a rod 13.

In other words, if an overvoltage is applied while switch C is turned on and load Z is operating, the resistance value of coil 4 remains unchanged, so the current flowing through it increases, resulting in an overcurrent, and armature 7 is attracted. Similarly to the above, the circuit is cut off, the excitation of the coil 4 is removed, and the switch C is opened via the rod 13 to cut off the current to the load Z, thus serving as an overvoltage protection circuit.

Further, the connection shown in FIG. 11 serves as an overcurrent protection circuit that opens switch D when an overcurrent flows through load Z.

Furthermore, FIGS. 12 and 13 show that, whereas in the embodiment described above, the armature 7 is attracted and the movable contact 8 is separated from the fixed contact 11, thereby cutting off the energization to the coil 4. In this example, a reed switch 30 is used, and the reed switch 30 is turned on and off by the leakage magnetic flux of the yoke 1.

That is, in the case of FIG. 12, when the coil is not energized or when a steady current is flowing, the reed switch 30 is in the OFF state, and when leakage magnetic flux due to overcurrent occurs.
In FIG. 13, the reed switch 30 is always biased to the ON state by the permanent magnet 31, and when leakage magnetic flux occurs, the magnetic flux of the permanent magnet 31 is canceled out. Indicates that the switch is in the OFF state.

Since the present invention has the above-described configuration and operation, the first movable member is attracted by the current flowing through the coil, and thereby performs necessary operations such as self-holding. When an overcurrent above a certain level flows through the coil during its operation, the leakage magnetic flux of the yoke is concentrated in the notch formed in the yoke, so the second movable member is attracted to the yoke and the switch turns OFF. Therefore, the current to the coil is cut off, the operation caused by the first movable member being pulled is stopped, and one coil performs necessary operations such as self-holding, circuit protection such as circuit interruption, and necessary operations. It is possible to perform two operations, ie, stop and stop, and therefore, there are many effects such as reduction in the installation space, simplification of the circuit, and reduction in the number of parts.

Furthermore, by causing the first movable member to self-hold and release the lock, the power window, sunroof, auto antenna, etc. of the automobile continue until the operation is completed, and the circuit is cut off as soon as the operation is completed. It enables so-called one-touch operation and has a simple configuration, making it ideal for these applications.

[Brief explanation of drawings]

1 and 2 are a plan view and a cross-sectional view taken along the line A-A of the first embodiment of the present invention, and FIGS. 3 and 4 are a plan view and a cross-sectional view taken along the line B-B of the second embodiment of the present invention. 5 and 6 are a sectional view and a plan view taken along the line CC of the third embodiment, FIGS. 7 and 8 are a plan view and a sectional view taken along the line D-D of the fourth embodiment, and FIG. 9 is a one-touch The circuit diagram when used in a type power window, Figure 10, shows the overvoltage protection circuit and the first
Figure 1 is a circuit diagram when used in an overcurrent protection circuit.
12 and 13 are plan views of the fifth and sixth embodiments. 1, 2... Yoke, 4... Coil, 5... Core (first movable member), 7... Armature (second movable member), 8... Movable contact, 11... Fixed contact, 15... ... Armature (first movable member), 20 ... Switch, Z ... Load, 30
...Reed switch.

Claims (1)

[Claims] 1. A yoke having a notch in a part, a coil fixed to the yoke, a first movable member attached to the yoke and attracted by energization of the coil, and a first movable member that is attached to the yoke in a direction that separates from the notch. When the coil is attached in a spring biased state and the current to the coil exceeds the magnetic saturation of the coil, leakage magnetic flux generated in the notch causes the coil to be attracted to the yoke against the spring bias force. a second movable member, and a switch that turns off when the second movable member is attracted to the yoke, and is configured to cut off current to the coil when the switch is turned off. An electromagnet characterized by: