JPH0243076Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an electromagnetic switch that is incorporated into a vehicle engine starting circuit or the like.

(Problems to be Solved by Prior Art and Ideas) As an electromagnetic switch that is incorporated into the engine starting circuit of a vehicle, the tip of the armature is biased away from the suction surface of the solenoid by a return spring. A thin plate spring is provided that operates integrally with the plate spring, a movable contact is provided at the tip of the plate spring, and the armature is attracted against the biasing force of the return spring by the excitation of the solenoid. A device in which the engine starting circuit is closed by bringing a movable contact into contact with the fixed contact is known, as disclosed in, for example, Japanese Patent Laid-Open No. 52-3143.

In such conventional electromagnetic switches, even if the movable contact and the fixed contact wear out due to contact with each other over time, the contact pressure of the movable contact against the fixed contact is reduced by a thin plate. This can be corrected by the force of the spring. However, when the starter motor starts, a large amount of current flows through the electromagnetic switch.
As mentioned above, the leaf spring for correcting the contact pressure of the movable contact in the conventional electromagnetic switch is a thin plate, so it easily generates heat, and the spring constant changes due to the heat generation, thereby creating a spring effect for correcting the contact pressure. will be lost. In order to deal with this, there was a problem in that the leaf spring had to be made larger, such as by increasing the thickness of the leaf spring.

(Purpose of the invention) The present invention was made in view of the above circumstances, and it is possible to fix the movable contact by keeping the spring constant of the leaf spring constant without increasing the size of the leaf spring for correcting the contact pressure of the movable contact. An object of the present invention is to provide an electromagnetic switch that maintains a constant contact pressure on a contact point.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, the base end is supported by a yoke surrounding the solenoid, and the distal end is urged in a direction away from the suction surface of the solenoid by a biasing means. A conductive plate having a movable contact member at its tip is disposed on the upper surface of the biased armature, and the movable contact member is brought into contact with or separated from the fixed contact member in conjunction with the armature to close or open a circuit. In the electromagnetic switch, the movable contact member is fixed to the conductive plate and is disposed on the distal end side of the armature so as to be movable in a direction toward and away from the fixed contact member; A spring force is applied to urge the movable contact member in a direction in which the movable contact member abuts the fixed contact member, and the conductive plate is movable toward and away from the armature, and its base end is connected to an external connection terminal. The upper surface of the armature and the lower surface of the conductive plate are separated by the excitation of the solenoid, so that only the spring force of the conductive plate acts on the fixed contact member. be.

(Operation) When the solenoid is energized, the armature is attracted and its upper surface is separated from the lower surface of the conductive plate, and the conductive plate is displaced toward the fixed contact member by its own spring force, and the movable contact member fixed to it is fixed. The movable contact member contacts the contact member and enters a closed state, at which time only the spring force of the conductive plate acts as a contact pressure of the movable contact member against the fixed contact member.

(Example) An example of the present invention will be described below based on the accompanying drawings.

1 and 2 are a vertical cross-sectional view and a top view of an electromagnetic switch according to the present invention, and in both figures, 1 is an electromagnetic switch, which has a recess 2c formed in a casing 2 and a main body of the electromagnetic switch ( (hereinafter simply referred to as the main body) 3, and a recess 2 of the casing 2.
The upper surface of c is closed by a lid member 5.

The casing 2 is made of a heat-resistant synthetic resin such as polybutylene terephthalate (PBT), for example.
A recess 2c with an open upper surface is formed over approximately half of the length in the longitudinal direction. A support piece 2a that is supported by a cathode terminal of a battery (not shown) extends substantially horizontally outward from one end surface in the longitudinal direction of the casing 2.
A groove 2b is opened in the other end surface of the casing 2 in the longitudinal direction.

The main body 3 includes a mounting terminal (external connection terminal) 7 electrically connected to the battery side, a fixed contact member 8 electrically connected to the starter motor circuit side (not shown), a solenoid 11, and an armature 1.
5, a conductive plate 16, and a movable contact member 17 as main components.

The mounting terminal 7 is formed by bending an elongated conductive metal plate, and includes a substantially horizontal first connection terminal 7a provided at one end in the longitudinal direction, and the first connection terminal 7a.
a first horizontal wall 7b connected to the first horizontal wall 7b; and a second substantially horizontal wall 7b connected to the first horizontal wall 7b via a first vertical wall 7c falling approximately vertically downward.
a horizontal wall 7d, a holding terminal 7f connected to an end of the second horizontal wall 7d via a second vertical wall 7e rising substantially vertically upward, and the second horizontal wall 7d.
It has a second connection terminal 7g that is located approximately in the middle in the longitudinal direction and is connected in a row approximately vertically upward.
Projections 7h each having a groove 7h' for supporting the conductive plate 16 are formed on both sides of the upper surface of the holding terminal 7f. The first connection terminal 7a of the mounting terminal 7 is
One longitudinal end surface of the casing 2 projects outward. first horizontal wall 7b, first vertical wall 7c,
The second horizontal wall 7d, the second vertical wall 7e, the second connection terminal 7g, and the holding terminal 7f are located inside the casing 2. The continuous portion from the first horizontal wall 7b to the second vertical wall 7e is housed and held within the casing 2 via the groove 2b, and is also electrically insulated. Second connection terminal 7g of mounting terminal 7
is electrically connected to one end 20a of an electrical load-side terminal 20 of the vehicle via a fuse device 4, which will be described later, and the other end 20b of the electrical load-side terminal 20 is located on the outer side of the top surface of the casing 2 in the longitudinal direction approximately in the middle thereof. is prominent. The holding terminal 7f of the mounting terminal 7 is mounted and fixed on the upper surface of the bottom wall of the recess 2c of the casing 2.

The fixed contact member 8 is made of a conductive metal plate, and has a third connection terminal 8a provided at one end in the longitudinal direction.
and a fixed contact 8b provided at the other end in series with the third connection terminal 8a. The other end of the fixed contact member 8 from the substantially middle portion in the longitudinal direction, that is, the fixed contact 8b is located inside the recess 2c of the casing 2, and is mounted and fixed on the upper surface of the bottom wall of the recess 2c. Further, one end of the fixed contact member 8 from approximately the middle portion in the longitudinal direction, that is, the third connection terminal 8a protrudes outward through the hole 2d of the casing 2, and is connected to the starter motor via a cord (not shown). It is connected to a connection terminal (not shown) on the circuit side.

The solenoid 11 consists of a bobbin 10 around which a coil 11a is wound, an iron core 12 fitted into the bobbin 10, and yokes 9 and 9' arranged on both sides of the bobbin 10. and the upper end surfaces of the yokes 9, 9' are approximately at the same height.
The solenoid 11 is disposed on the other end side of the casing 2 from a substantially intermediate portion in the longitudinal direction, while being assembled and housed in the recess 2c. The terminal of the coil 11a of the solenoid 11 is connected to two coil terminals 21, 21.
is connected to via connection terminals 22, 22.
The upper ends of both coil terminals 21, 21 protrude outward from the upper surface of the casing 2, and the protruding end of one coil terminal 21 is connected to the starter motor circuit via a cord (not shown), and the protruding end of the other coil terminal 21 is connected to the starter motor circuit via a cord (not shown). The protruding end of the coil terminal 21 is connected to a load side circuit of a main switch (none of which is shown) via a cord and a starter switch.

The armature 15 is constructed by fitting a square hole (not shown) formed approximately in the center of the base end side into a protrusion (not shown) formed at the upper end of one yoke 9'. , is rotatably supported at the upper end of one yoke 9'. The base end of the armature 15 faces the holding terminal 7f of the mounting terminal 7 with a slight distance therebetween. The tip of the armature 15 is a free end, and a hole 15b is bored approximately in the center thereof.
A solenoid 1 is attached to the lower surface of both sides in the width direction on the tip side of the armature 15.
1 (upward in FIGS. 1 and 3) are provided return springs 13, 13'.

The conductive plate 16 is disposed above the armature 15, and is fixed by inserting its base end into the groove 7h' of the projection 7h of the holding terminal 7f of the mounting terminal 7.
It is supported by this holding terminal 7f. The vicinity of the base end of the armature 15 is engaged and held in a groove of a protrusion 5a formed at a predetermined location on the lower surface of the lid member 5, and the tip is a free end. A hole 16a is bored approximately at the center of the tip of the conductive plate 16. In this attached state, the conductive plate 16 is applied with a spring force in a direction in which its distal end approaches the solenoid 11 (downward in FIGS. 1 and 3). The spring force of the conductive plate 16 is the return spring 1 of the armature 15.
3 and 13' (the upward biasing force in FIGS. 1 and 3). When the switch is opened (off), the spring 1 is returned so that the top surface of the tip of the armature 15 comes into contact with the bottom surface of the tip of the conductive plate 16, as shown by the solid line in FIG.
3 and 13', and when the switch is closed (on), the armature 15 is attracted to the solenoid 11 against the spring force of the return springs 13 and 13', as shown by the two-dot chain line in FIG. Then, the upper surface of the tip of the armature 15 is separated from the lower surface of the tip of the conductive plate 16. The conductive plate 16 is displaced in the direction approaching the solenoid 11 by its own spring force, and as a result, the lower surface of the large diameter portion 17a of the movable contact member 17 attached and fixed to the tip of the conductive plate 16 is moved toward the fixed contact member 8. is brought into contact with the upper surface of the fixed contact 8b. That is, the mounting terminal 7 and the fixed contact member 8 are electrically connected to each other via the movable contact member 17.

As shown in FIGS. 1 and 3, the movable contact member 17 consists of a large diameter portion 17a and a small diameter portion 17b connected to the upper surface of the large diameter portion 17a. An annular groove 17c is formed throughout. The small diameter portion 17 of this movable contact member 17
b is fitted into the hole 15b of the armature 15 so as to be movable in the axial direction (the direction in which it moves toward and away from the fixed contact 8b of the fixed contact member 8). Further, the annular groove 17c of the movable contact member 17 is fitted and fixed within the hole 16a of the conductive plate 16. The conductive plate 16 and the movable contact member 17 can be integrally interlocked. The lower end surface of the annular groove 17c of the small diameter portion 17b of the movable contact member 17 and the small end surface 17 of the large diameter portion 17a.
The dimension d ₁ between a′ and the thickness d ₂ of the armature 15 is
is set to a value greater than .

Note that when the lower surface of the large diameter portion 17a of the movable contact member 17 is in contact with the upper surface of the fixed contact 8b of the fixed contact member 8, the upper end surface 17a of the large diameter portion 17a is larger than each upper end surface of the yokes 9, 9' and the iron core 12. ′ is set to be lower.

The fuse device 4 has a plurality of blade fuses 26a and 26b fitted and held in a fuse guide 25 on the upper surface of the casing 2. One connection terminal 26a ₁ of the main side blade fuse 26a
is electrically connected to one end 20a of the electrical load side terminal 20 of the vehicle. The other end 20b of this electrical load side terminal 20 is connected to the load side circuit of the vehicle via a cord and a main switch (both not shown).

The casing 2 is fitted into a recess (none of which is shown) on the upper surface of the battery, the holes of the first connection terminal 7a and the support piece 2a are fitted with the anode terminal and cathode terminal of the battery, respectively, and the bolts are inserted. (none of which are shown), the electromagnetic switch 1 is attached and fixed to the upper surface of the battery.
In such a fixed state, the first connection terminal 7a
is electrically connected to the anode side of the battery.
On the other hand, the support piece 2a does not serve as an electrical contact point.

Next, the operation of the electromagnetic switch 1 having the above configuration will be explained.

To start the engine, after closing the main switch, operate the starter switch (both not shown) and turn on the solenoid 11 of the electromagnetic switch 1.
When energized, armature 15 returns spring 1
It is attracted by the solenoid 11 against the spring force of the armature 15 , and the upper surface of the armature 15 on the front end side is separated from the lower surface of the conductive plate 16 on the front end side. As a result, the conductive plate 16 is released from the spring force of the return springs 13 and 13', and its tip is displaced in the direction toward the solenoid 11 solely by its own spring force. As a result, the large diameter portion (movable contact) 17a of the movable contact member 17 attached to the tip of the armature 15
The lower surface of the fixed contact member 8 is pressed against the upper surface of the fixed contact 8b of the fixed contact member 8 (the state shown by the two-dot chain line in FIG. 3). In this state, the distal end side of the armature 15 is not in contact with either the conductive plate 16 or the movable contact member 17, so the movable contact member 17
Only the spring force of the conductive plate 16 itself is loaded, and only the spring force of the conductive plate 16 acts as a contact pressure of the movable contact member 17 against the fixed contact member 8.
Further, since the base end of the conductive plate 16 is supported by the holding terminal 7f of the mounting terminal 7 through the groove of the protrusion 5a of the lid member 5, it is not affected by the heat generated by the solenoid 11. The spring constant of the conductive plate 16 does not change, and a constant spring force is always maintained.

As described above, the large diameter portion 17a of the movable contact member 17
is pressed against the fixed contact 8b of the fixed contact member 8, thereby electrically connecting the mounting terminal 7 and the fixed contact member 8 via the conductive plate 16, thereby closing the electromagnetic switch 1. . As a result, the starter motor circuit is closed and electricity from the battery is supplied to the starter motor (both not shown), which drives the starter motor, thereby driving the engine crankshaft (both not shown). The engine is started by being rotated.

After starting the engine, when the starter switch is released, the solenoid 11 is deenergized and
The upper surface of the distal end of the armature 15 is pressed against the lower surface of the distal end of the conductive plate 16 by the spring force of the return springs 13 and 13'.
5 and the movable contact member 17 integrally return the spring 1
3 and 13', the large diameter portion 17a of the movable contact member 17 is separated from the fixed contact 8b of the fixed contact member 8, and the electromagnetic switch 1 is is opened, and power to the starter motor is cut off. In this manner, when the switch is opened (off), the upper surface of the tip of the armature 15 is moved upward by the spring force of the return springs 13, 13' and is pressed against the lower surface of the tip of the conductive plate 16, and then , the conductive plate 16, the armature 15, and the movable contact member 17 are integrally returned to the spring 1.
Because it is displaced upward by the spring force of 3,13',
The movement of separating the movable contact member 17 and the fixed contact member 8 is performed smoothly, and the opening operation is performed instantaneously.

In addition, in the above embodiment, the electromagnetic switch 1
Since the electromagnetic switch 1 is assembled into a recess provided in the battery, there is no need to secure a special space for installing the electromagnetic switch 1, and accordingly, a larger space can be taken up for the arrangement of other engine accessories. This is advantageous when laying out these parts.

In addition, since the first connecting terminal 7a led out of the casing 2 and the support piece 2a of the casing 2 are fastened to the anode and cathode terminals of the battery with bolts, respectively, the electromagnetic switch 1 is fixed to the battery. It becomes possible to fix the electromagnetic switch 1 without providing any special member such as a bracket.

(Effects of the Invention) As detailed above, the present invention provides an upper surface of an armature whose base end is supported by a yoke surrounding the solenoid, and whose distal end is urged by an urging means in a direction away from the suction surface of the solenoid. An electromagnetic switch is provided with a conductive plate having a movable contact member at its tip, and the movable contact member is brought into contact with or separated from a fixed contact member in conjunction with the armature to close or open a circuit. The movable contact member is fixed to the conductive plate and is disposed on the distal end side of the armature so as to be movable in a direction toward and away from the fixed contact member, and further, the movable contact member is fixed to the conductive plate. A spring force is applied to the conductive plate in the direction of contacting the fixed contact member, and the conductive plate is movable toward and away from the armature, and its base end is connected and held to the external connection terminal. The present invention is characterized in that the upper surface of the armature and the lower surface of the conductive plate are separated by the excitation of the solenoid, so that only the spring force of the conductive plate acts on the fixed contact member.

Therefore, the effect is that the spring constant of the leaf spring can be kept constant and the contact pressure of the movable contact member against the fixed contact member can be kept constant without increasing the size of the leaf spring, that is, the conductive plate that is the leaf spring. play.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a vertical sectional view of an electromagnetic switch according to the present invention, and FIG.
FIG. 3 is a top view with the lid member removed, and FIG. 3 is an enlarged view of the main part of FIG. 1. 1... Electromagnetic switch, 7... Mounting terminal (external connection terminal), 8... Fixed contact member, 11... Solenoid, 13, 13'... Return spring (biasing means), 1
5... Armature, 16... Conductive plate, 17...
Movable contact member.

Claims (1)

[Scope of utility model registration request] A conductive plate having a movable contact member provided at the tip is disposed on the upper surface of the armature whose base end is supported by a yoke surrounding the solenoid and whose tip end is urged by a biasing means in a direction away from the attraction surface of the solenoid. In the electromagnetic switch, the movable contact member is connected to the armature and brought into contact with or separated from the fixed contact member to close or open a circuit, wherein the movable contact member is fixed to the conductive plate. and a spring force that is disposed on the distal end side of the armature so as to be movable in a direction toward and away from the fixed contact member, and further biases the conductive plate in a direction in which the movable contact member abuts on the fixed contact member. and the conductive plate is movable toward and away from the armature, and its base end is connected and held to an external connection terminal, and when the solenoid is energized, the upper surface of the armature and the lower surface of the conductive plate are 1. An electromagnetic switch characterized in that the conductive plates are separated from each other so that only the spring force of the conductive plate acts on the fixed contact member.