JPS581496B2 - magnetic contact spring element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic switch in which a movable contact piece of a magnetic spring element is directly driven by electromagnetic attractive force, and in particular to a magnetic contact spring that can improve the switch characteristics of the switch. This relates to the improvement of elements.

FIGS. 1 and 2 show a partially cutaway front view and a side view of a multi-contact integrally sealed electromagnetic switch as an example of the object of the present invention.

In the figure, 1 is a magnetic plate that also serves as the base of this switch. On this plate 1, there are, for example, 11 contact caps horizontally and 22 contact caps 2 vertically in two rows A and B, with glass hermetic contact caps 2 at 22 locations in the Y section. The 22 contact caps 2 are each independently insulated by a glass 3.

Then, on the head of the contact cap 2, both the A row and the B row have Z1,
Fixed contacts 4 are welded to each of eight locations excluding Z2 and Za.

Reference numeral 5 designates a backstop made of a soft magnetic material, and as shown in FIG. 3, a magnetic contact spring element 6 made of a soft magnetic thin plate spring material is attached to the contact cap 2 side of the backstop 5.

Further, the magnetic contact spring element 6 has a fan-shaped movable contact piece 61.
, two spring parts 62, 63 and a fixing part 64 are integrally formed in plural sets.

The movable contact piece 61 has a movable contact 7 in the corresponding part of the fixed contact 4, and the fixed part 64 is
By fixing the marking portion 8 with a suitable adhesive means such as welding, it is configured to be able to move independently in correspondence with the fixed contact 4.

In addition, convex portions 9 for obtaining the contact gap g necessary for backstop operation are provided at three locations at the left end, center, and right end corresponding to the contact caps indicated by Z1, Z2, and Za, and each of these convex portions 9 is welded to the contact cap 2 by a small weld projection 10 formed at the tip.

Therefore, the backstop 5 has three protrusions 9 welded to the contact cap 2, so that the three locations indicated by Z1, Z2, and Z3 serve as common contact terminals for the magnetic contact spring elements 6.

Then, the switch configured as described above is covered with the case 11 in nitrogen gas, and the case 11 and the plate 1 are covered.
The overlapping surface 12 is hermetically sealed by laser welding or the like.

Further, reference numeral 13 denotes an iron core, which is fixed to the contact cap 2 by welding or the like, and the stepped portion 14 of the iron core 13 also serves as a terminal for attaching the switch to a printed circuit board or the like.

15 is a coil wound around the outer periphery of the iron core 13.

In contact operation, when a current is passed through the coil 15 wound around the iron core, the magnetic flux generated from the iron core 13 passes through the contact cap 2, and the movable contact piece 61 corresponding to each fixed contact 4 moves to each fixed contact 4. When the current in the coil 15 is cut off, the coil 15 self-restores itself to a position in contact with one surface of the backstop 5 due to its elasticity.

In this example, 16 contacts are opened and closed at a time, but it is also possible to divide the coil 15 into an X coil and a Y coil and drive only desired contacts coordinate-selectively.

FIGS. 4a and 4b are schematic diagrams showing the operating state of the magnetic contact spring element 6 as a driving magnetic field is applied.

When opened, the magnetic contact spring element 6 is in surface contact with the backstop 5 as shown in Figure a.

Then, when an attractive force is applied, the magnetic contact spring element 6
As shown in the figure, the spring parts 62 and 63 are bent with the fixed part 64 as the intersection, and the movable contact piece 61 is attracted to the fixed contact 4 using the free ends of the spring parts 62 and 63 as fulcrums, resulting in the state shown in the figure.

The spring structure of the magnetic contact spring element 6 is extremely excellent in that it does not rotate during operation and can achieve stable and good human contact.

As mentioned above, the backstop 5 is made of a soft magnetic material, and the purpose of making it magnetic is to function as a magnetic yoke for the magnetic flux from the iron core 13, which improves magnetic efficiency and reduces power consumption. It becomes possible to drive.

By the way, a soft magnetic material has a smaller residual magnetism than a semi-hard or hard magnetic material, but since it is a magnetic material, it has magnetic hysteresis and generates a certain amount of residual magnetism.

For this reason, the backstop 5 and the magnetic contact spring element 6 made of magnetic materials are overlapped, and the spring element 6 is attached to the backstop 5.
In a switch having a structure such as the present one in which the contact operation is achieved by pulling the contact further apart, when the switch is operated, an attractive force in the opposite direction due to residual magnetism is generated between the backstop 5 and the magnetic contact spring element 6, and the contact operation time becomes longer. It ends up.

In addition, this reverse suction force varies depending on the smoothness of each movable contact piece 61 and the state of contact with the backstop 5, so
Remove variations in contact operating time and chatter time,
This makes it difficult to provide high-precision, high-performance switches.

The present invention is intended to solve the above-mentioned problems, and provides a magnetic contact spring element that can effectively and easily reduce the reverse attraction force and achieve high-speed and high-precision switching. .

The object of the present invention is to have a movable contact piece integrally connected to the surface of a thin magnetic spring plate, two spring parts and a fixed part,
The spring portion extends substantially perpendicularly in parallel from both ends of the fixing portion, and has a shape in which the ends are bent in an L shape and connected. In the magnetic contact spring element, the movable contact piece is formed by being derived from the shape of the movable contact piece, and the two spring portions are arranged linearly with respect to the geometric center line of symmetry of the movable contact piece. The ratio a/b of the gap size a between the contact piece and the spring part and the gap size b between the movable contact piece and the fixed part is set to 0.
This can be achieved by a magnetic contact spring element characterized by having a value of 2 to 0.5.

Hereinafter, one embodiment of the present invention will be explained with reference to FIGS. 5 to 9 while comparing it with a conventional example.

The present invention is characterized in that the movable contact piece 61 is made smaller by a certain size than the conventional one, thereby reducing the reverse suction force.

That is, FIG. 5 is the conventional one, and FIG. 6 is the one according to the present invention, and as can be understood from the illustrations, there is a gap 60 between the two.
, movable contact piece 61, spring parts 62, 63, and fixed part 64
The present invention is the same in that the magnetic contact spring element 6 is formed, but differs from the conventional one in that the movable contact piece 61 is made smaller.

Note that the gap 60 is a gap between the movable contact piece 61, the spring parts 62 and 63, and the fixed part 64.

In Fig. 8a, the vertical axis is time (ms), and the horizontal axis is the contact operating time, where the ratio a/b of the gap size a between the movable contact piece and the spring part and the gap size b between the movable contact piece and the fixed part is taken. (Curve A) and chatter time (Curve B).

The conventional magnetic contact spring element used in this experiment is shown in Figure 8b.
A magnetic material of 15Ni-Fe alloy with a thickness of about 0.1
mm, and the ratio a/b of the gap size a between the movable contact piece and the spring part and the gap size b between the movable contact piece and the fixed part is 1
(conventional type), one with the a/b ratio of 0.5, and one with the a/b ratio of 0.2 were made, and these were used to manufacture a switch as shown in Figure 4. The contact was operated (a magnetic field of about 150 AT was applied to the iron core 13), and the contact operation time and chatter time at that time were measured.

The results are as shown in FIG. 8, and as the number of movable contact pieces 61 is decreased, both the operating time and the chattering time become smaller, and the respective variations (arrows) also become smaller.

In particular, it is good when a/b is 0.5 or less.

On the other hand, if the movable contact piece 61 is made smaller, the magnetic attraction force during contact operation tends to decrease as shown in FIG.

This type of switch has a suction force of at least 2
Since 0 g is necessary, a/b is preferably 0.2 or more.

Therefore, in the case of this example, a/b is 0.2 to 0.
If it is set to 5, a switch exhibiting high speed and highly accurate contact operating characteristics can be obtained.

Figure 7 shows another example of reducing the number of movable contact pieces 61, in which figure a shows the movable contact piece 61 in a semicircular shape, and figure b shows it in a circular shape to reduce the area. It is something.

As described above, according to the magnetic contact spring element of the present invention, it is possible to easily reduce the reverse attraction force, and as a result, the contact operating time and chattering time are shortened, and the variation is also reduced, so that high-speed, high-precision We can provide a switch.

[Brief explanation of the drawing]

1 to 4 a and b are diagrams showing the structure of a multi-contact integrally sealed electromagnetic switch, which is an example of the object of the present invention, and FIG. 5 is a plan view showing a conventional magnetic contact spring element. FIG. 6 is a plan view showing a magnetic contact spring element according to the present invention, and FIG. 7a
, b are plan views of magnetic contact spring elements according to other embodiments of the present invention, and FIGS. 8a and 8b and FIG. 9 are diagrams showing experimental results according to the present invention. Explanation of symbols, 5...Backstop, 6...
...Magnetic contact spring element, 60...Gap, 61
......Movable contact piece, 62, 63... Spring part, 64... Fixed part.

Claims (1)

[Claims] 1 It has a movable contact piece integrally connected to the surface of a thin plate magnetic spring material, two spring parts, and a fixed part, and the spring part is led out in parallel at a substantially right angle from both ends of the fixed part. , and the end portions are bent in an L shape and connected, and the fan-shaped movable contact piece is led out from approximately the center of the connection portion toward the fixed portion, and the two springs are connected to each other. In the magnetic contact spring element in which the portions are arranged line-symmetrically with respect to the geometric center line of symmetry of the movable contact piece, a gap size a between the movable contact piece and the spring portion, and a gap size a between the movable contact piece and the fixed portion. A magnetic contact spring element characterized in that the ratio a/b to the gap size b is 0.2 to 0.5.