JPS5852537Y2 - Movable iron piece type instrument - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a movable iron piece type instrument that allows easy adjustment of the twist angle of the pointer.

Movable iron-shaped instruments have a simple structure and good vibration resistance, so they are widely used in automobile ammeters and the like.

FIG. 1 is an exploded perspective view of a conventional movable iron piece type instrument.

In the figure, 1 is a pointer, 2 is a dial, 3 is a mounting plate, 4 is a magnet with magnetic poles N and S, 5 is a base, and 5a is a base 5
6 is a terminal bar for connecting a lead wire fixed to the base 5, 7 is a movable iron piece, 7a, 7
8 is a pointer shaft fixed to the center of the movable iron piece 7, 9 is a holding plate, and 9a is a bearing formed at the center of the holding plate 9. Part 1
0 is a yoke formed in a U-shape, 10atlOb is a yoke magnetic pole portion formed in two pieces (total 4 pieces) at each end of the image of the yoke 10, penetrating the holding plate 9 and bent on the front surface thereof, and 11 is a yoke magnetic pole portion. A coil is wound around a yoke 10, and both ends thereof are connected to a terminal bar 6.

The yoke 10 and the coil 11 constitute a driving electromagnet.

The pointer shaft 8 is pivotally supported by the bearing hole 5a and the bearing portion 9a, and the movable iron piece 7 is rotatably disposed between the magnet 4 and the yoke magnetic pole portions 10a and 10b.

FIG. 2 is an explanatory diagram for explaining the operating principle of this meter.

During steady state, the movable iron piece 7 is attracted to the magnet 4 and the magnetic pole part 7
a and 7b are opposed to the magnetic poles N and S, respectively, and are stopped at the zero stop position as shown in the figure.

At this time, the pointer 1 shown in FIG. 1 is pointing to the zero scale of the dial 2.

Here, current flows through the coil 11 and the yoke magnetic pole portion 10a
When the magnetic pole parts 7a and 7b are excited to the n-pole and the yoke magnetic pole part 10b to the south pole, respectively, the magnetic pole parts 7a and 7b become the yoke magnetic pole parts IQa and 10b.
, and the movable iron piece 7 rotates in the direction of the arrow.

The movable iron piece 7 has the attractive force of the magnetic poles N and S of the magnet 4 against the magnetic pole parts 7a and 7b, and the yoke magnetic pole part 10a.

It rotates to a position where the suction force of 10b is balanced and stops.

At this time, the scale corresponding to the value of the current flowing through the coil is indicated by the pointer.

In such a movable iron piece type instrument, the thickness of the pointer 1 generally does not match the current of the coil 11 as set due to variations in each component, so the torsion angle precision of the pointer 1 is adjusted after assembly.

When adjusting the torsion angle accuracy of the pointer, conventionally, adjustment work has been carried out by changing the attractive force of a magnet or drive electromagnet applied to the movable iron piece.

In the instrument with the structure shown in Fig. 1, the magnet and the driving electromagnet are arranged in opposite directions in the axial direction with the movable iron piece in between, so by bending the movable iron piece either upward or downward, The torsion angle accuracy of the pointer can be adjusted by increasing the influence of either the magnet or the drive electromagnet to change the swing angle characteristics with respect to the coil current.

However, in this case, there was a problem in that the movable iron piece would jump in the axial direction, making it impossible to obtain stable swing angle characteristics.

Furthermore, an instrument having a structure in which a magnet and a driving electromagnet are arranged in the same direction and at approximately the same position with respect to the movable iron piece in the axial direction has also been considered.

In this type of structure, the movable iron piece is always attracted to one side in the axial direction, so jumping does not occur, but since the magnet and drive electromagnet are in the same direction, even if the movable iron piece is bent, the influence of both magnets is The problem is that it is difficult to adjust the torsion angle by bending the movable iron piece.

As described above, the conventional movable iron piece type instrument has the disadvantage that it is difficult to adjust the torsion angle accuracy with a simple operation.

The present invention was made in order to eliminate such drawbacks of the conventional method, and its purpose is to provide a movable iron piece-shaped instrument that can stably adjust the torsion angle accuracy by bending the movable iron piece. be.

In order to achieve this purpose, the present invention provides two magnets with different poles facing each other through a movable iron piece, and the magnetic flux center line of these magnets is aligned with the movable iron piece in the direction of the pointer axis. The pointer shaft is thrust supported by a bearing part of a non-magnetic holding plate which is placed between the electromagnets and has a driving electromagnet attached thereto.

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

FIG. 3 is a longitudinal sectional view of an embodiment of the movable iron piece type meter according to the present invention, FIG. 4 is a sectional view taken along IV-IV in FIG. 3, and FIG. 5 is a sectional view taken along V-■ in FIG. 3. .

In the figure, the same or corresponding parts as in FIG. 1 are given the same reference numerals.

A magnet housing hole 5b is provided on the bottom surface of the base 5 made of non-magnetic material.
, 5c are formed, and disk-shaped magnets 14a and 14b made of ferrite are accommodated therein, respectively.

This magnet 14a. 14b is held stationary within the magnet housing holes 5b, 5c by protrusions 5d, 5e formed on the inner surfaces of the magnet housing holes 5b, 5c and a retaining plate 9 made of a non-magnetic material.

The magnets 14 a t 14 b are magnetized toward the center of the disk, with one surface serving as a N pole and the other surface serving as an S pole. However, the N pole of the magnet 14 a faces inward and is similar to the magnetic pole of the movable iron piece 7 . The magnet 14 faces the central tip of the portion 7a with a predetermined gap in the radial direction.
b are arranged such that the S pole faces inward and faces the center tip of the magnetic pole portion 7b with a predetermined gap in the radial direction.

Here, the yoke magnetic pole portion 10a of the drive electromagnet. 10b faces the movable iron piece 7 with a downward distance in the direction of the pointer axis, but the magnetic flux center line A of the magnets 14a and 14b is between the movable iron piece 7 and the surfaces of the yoke magnetic pole parts 10a and 10b. It is supposed to be located.

In addition, since the magnets 14a and 14b have the highest magnetic flux density at the disc center, the line connecting the disc centers of both magnets is the magnetic flux center line A.
becomes.

Further, as in FIG. 2, the magnetic flux center line A is perpendicular to the line connecting the yoke magnetic pole portions 10a and 10b in plan view.

In such a configuration, the movable iron piece 7 has its magnetic pole portion 7a
, 7b are attracted slightly downward and outward by the magnets 14a and 14b, and are at the zero rest position.

Here, when a current is passed through the coil 11, the yoke magnetic pole portion 10a
, 10b are magnetized, and the movable iron piece 7 rotates in the manner described in FIG.

In this case, in order to adjust the torsion angle accuracy, the movable iron piece 7 or its magnetic pole parts 7a and 7b are bent up and down to change the gap facing the yoke magnetic pole parts 10a and 10b, thereby reducing the magnetic influence of the drive electromagnet on the movable iron piece 7. Adjust the force.

At this time, since the gap between the magnet 14at14b and the magnetic pole parts 7a and 7b hardly changes, the magnet 14at14b
The magnetic influence on the movable iron piece 7 does not change much.

Therefore, it is possible to perform good twist angle accuracy adjustment.

Note that at this time, the movable iron piece 7 is a magnet 14a.

14b and the yoke magnetic pole parts 10a and 10b, the pointer shaft 8 is thrust-received by the bearing part 9a of the holding plate 9 with a predetermined force.

Therefore, even if the movable iron piece 7 is bent for adjustment, no jumping occurs in the axial direction, and stable plate characteristics can always be obtained.

In this embodiment, ferrite is used as the magnet, and the magnet can be placed in a predetermined position by inserting the magnet into the accommodation hole formed in the base and fixing the holding plate with the drive electromagnet attached to the base, making it easy to assemble. becomes easier and costs are reduced.

Although disk-shaped magnets were used in the above embodiments, it goes without saying that magnets of various shapes can be applied.

As described above, according to the movable iron piece type instrument according to the present invention, it is possible to stably adjust the plate thickness accuracy of the pointer by simply bending the movable iron piece, and without causing any jumping in the axial direction. This has the effect of improving the accuracy of meter readings.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view of a conventional movable iron piece type meter, Fig. 2 is an explanatory diagram of its operating principle, Fig. 3 is a longitudinal sectional view of an embodiment of the movable iron piece type meter according to the present invention, and Fig. 4 is a IV-I in Figure 3
V sectional view, FIG. 5 is a sectional view taken along ■--■ in FIG. 3. 1... Pointer, 2... Dial board, 5...
... Base, 5 b t 5 c ... Magnet accommodation hole, 5 d , 5 e ... Protrusion, 7 ...
Movable iron piece, 7a, 7b...Magnetic pole part, 8...
... Pointer shaft, 9 ... Holding plate, 9a ...
・Bearing part, 10...Yoke, 1Qa, 10b・
... Yoke magnetic pole part, 11 ... Coil, 1
4 a t 14 b... Magnet.

Claims (1)

[Scope of utility model registration request] A rotatably supported pointer shaft, a plate-shaped movable iron piece that can be bent in the direction of the pointer shaft with the pointer shaft fixed in the center, and a magnet that attracts the movable iron piece to keep it in a zero stationary position. In the movable iron piece type instrument, the magnet is provided with a drive electromagnet that attracts and rotates the movable iron piece against the attraction force of the magnet, and the magnet is connected to a different polarity through the movable iron piece from the side of the movable iron piece. It consists of two magnets arranged to face each other, and the magnetic flux center line of these two magnets is located between the movable iron piece and the driving electromagnet in the direction of the pointer axis, and the driving electromagnet is attached to a non-magnetic magnet. A movable iron piece type instrument in which the pointer shaft is thrust by a bearing part of a holding plate made of a material by the attraction force of the magnet.