JPH03255371A - Movable linear wide angle instrument - Google Patents

Abstract

PURPOSE:To easily manufacture an instrument compact in size with good linearity scales by forming a yoke made of drawn material of soft iron and a core concentrically with a gap, and inserting and bonding a tile-shaped magnet of a rare earth element into the gap. CONSTITUTION:A cylindrical yoke 11 is made of drawn material of soft iron the inner surface of which is only the inner surface of a cylinder. This yoke 11 and a cylindrical core 12 the outer surface of which serves only as the outer surface of a cylinder are formed concentrically with a gap 13 therebetween. A tile magnet 14 of a rare earth element is inserted and bonded by 15 into the gap 13. Therefore, the concentricity with high accuracy is obtained, and positioning adjustment is made easy. As the dimensional accuracy of the confronting surfaces of the yoke 11 and core 12 is improved, the density of the magnetic flux in the gap becomes uniform, making the scale mark favorably linear. Moreover, if the magnet 14 is made thin, the instrument becomes compact in size. Accordingly, it is easy to manufacture a compact instrument with favorable linear scale mark at reduced costs.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention is directed to a movable ring type wide-angle instrument that has good coil-current characteristics, is easy to manufacture, and can be made compact.

<Prior Art> FIGS. 14 and 15 are explanatory diagrams of the configuration of a conventional example that has been commonly used.

In the figure, 1 is a yoke, and 2 is a core inserted into the yoke 1 with a gap 3 maintained.

4 is a magnet placed in the gap between the yoke 1 and the core 2.

In this case, alnico magnets are used, and have a rectangular shape that bites into the yoke 1 and core 2. This is to ensure the necessary magnetic force.

The yoke 1 and the core 2 have a flat surface 5 for attaching the magnet 4.
6 is formed, and the yoke 1 and core 2 have a complicated shape.

7 is a moving coil, and 8 is a pointer whose one end is connected to the moving coil.

In the above configuration, when an input signal is input to the movable coil 8, the movable coil 8 is displaced in response to the input, and the pointer is rotated in response to the input signal.

<Problems to be Solved by the Invention> However, in such a device, (1) position adjustment of the concentricity of the yoke 1 and the core 2 is difficult.

Place the flat part 5.6 on the yoke 1 and core 2! Accurate formation is difficult when punched cores are stacked one on top of the other without causing misalignment.

Furthermore, the yoke 1 and the core 2 are connected by a magnet 4 having 2,000 faces.
There is an upper limit to manufacturing in order to connect the yoke 1 and the core 2 and configure the concentricity of the yoke 1 and the core 2 with high precision.

Therefore, it is difficult to use a pre-printed scale plate for a meter with an accuracy of ±1%, and it is necessary to write a scale for each tube passage, which takes a lot of time.

(2) The yoke 1 and the core 2 are expensive.

A concentric cylindrical space 1 is formed between the inner surface of the yoke 1 and the outer periphery of the core 2.
Form I13 and empty wI! Since the flat portions 5 and 6 are required for joining with the rectangular parallelepiped magnets, the shape becomes complicated, and the yoke 1 and core 2 are constructed by laminating more than ten punched iron plates.

As a result, the yoke 1 and the core 2o require about 30 laminated components, which cannot be manufactured at low cost.

There are also products made of sintered alloys instead of laminated iron cores, but they are expensive.

(3) Dimensional accuracy of yoke 1 and core 2.

In a laminated core or sintered alloy, the dimensional accuracy of the inner surface of the yoke 1 and the outer surface of the core 2, which form the void 3, is 0.1 mm to 0.
．． The limit is about 2 mm.

Therefore, in order to manufacture a movable linear wide-angle meter with an accuracy of ±1%, it is necessary to make a scale plate with a scale for each piece, which is time consuming and costly.

(4) Adjusting the length of magnet 4.

Since the accuracy of the spacing between the yoke 1 into which the magnet 4 is inserted and the flat part 5.6 of the core 2 is about 0.1 to 0.2 mm, the magnet 4 may be prepared with a dimension of 0.21 to 0.2 mm. Yes, the cost is high.

(5) Adjustment of thickness H of yoke 1.

The thickness H of the yoke 1 is especially important for tote band type instruments, where the moving parts are made of thin metal elastic ribbons! l! Since this is a tension type, the thickness H of the yoke 1 has a direct effect on the length of the tote band, that is, its torque. There must be.

(6) Machining the pole faces of alnico magnets.

Alnico magnets have high hardness, require surface grinding, and are expensive.

The present invention solves these problems.

SUMMARY OF THE INVENTION An object of the present invention is to provide a movable ring type wide-angle instrument that has good linearity in scale characteristics, is easy to manufacture, and can be made compact.

Means for Solving the Problems To achieve this object, the present invention provides (1) a movable ring type wide-angle instrument in which a core and a yoke are arranged concentrically with a gap therebetween; 1. A movable linear wide-angle instrument comprising: a core and a yoke made of wood; and a tile-shaped rare earth magnet disposed in the gap.

(2) The movable linear wide-angle instrument according to claim 1, wherein both ends of the magnet are formed so as to be parallel to the direction of magnetization.

It is composed of

Effect> In the above configuration, when an input signal is input to the movable coil, the movable coil is displaced in response to the input, and the pointer is rotated in response to the input signal.

Hereinafter, a detailed explanation will be given based on examples.

<Example> Fig. 1 and Fig. 2 are explanatory diagrams of the main part configuration of an embodiment of the present invention, Figs. 3 and 4 are explanatory diagrams of the main part composition of Fig. 1, Fig. 5,
FIG. 6 shows an embodiment in which a movable part is attached to FIG. 1.

In the figure, structures with the same symbols as in FIGS. 14 and 15 represent the same functions.

Hereinafter, only the differences from FIGS. 14 and 15 will be explained.

In the figure, 11 and 12 are concentrically arranged yokes and cores made of drawn soft iron pipes.

Reference numeral 13 denotes a gap formed by the yoke 11 and the core 12.

14 is a tile-shaped magnet made of samarium cobalt and placed in the gap 13. In this case, it is glued 15.

A flange 21 is fitted to the upper surface of the yoke 11 to attach parts for rotating the movable part, parts for attaching a scale plate, etc. to the excitation part with the center of the excitation part as the rotation axis.

Reference numeral 22 denotes a flange for attaching parts for pivotally supporting the movable part, and a flange for attaching a metal fitting for screwing the excitation part to the instrument housing.

5 and 6 show an embodiment in which a movable part is attached to the structure shown in FIG. 1.

31 is a movable part attached to the excitation part in FIG.

32 and 33 are support frames that support the movable part 31, and the flange 2
1.22.

Note that the movable part may be a tote band support.

In the above configuration, when an input signal is input to the movable coil 7, the movable coil 7 is displaced in response to the input, and the pointer is rotated in response to the input signal.

As a result, (1) the concentricity of the yoke 11 and the core 12 can be easily adjusted;

A void 13 is formed only by a cylindrical yoke 11 made of drawn material and having only a cylindrical inner surface, and a cylindrical core 12 whose outer surface has only a cylindrical outer surface.

Since a tile-shaped magnet 14 made of a part of a cylinder is inserted into this gap 13 and joined 15, highly accurate concentricity can be obtained relatively easily, and m adjustment using an assembly jig or the like is easy. Become.

In machining, it is generally easier to machine a part into a cylindrical shape than to machine a flat part with higher dimensional accuracy. That is, it is relatively easy to manufacture each part concentrically in a circle m shape with high precision.

Therefore, positioning adjustment is easier than in the conventional case where the surfaces of the yoke 1 and the core 2 with respect to the gap 3 must be cylindrical surfaces, and the joints with the magnets 4 must be formed with a flat surface.

(2) Improving the uniformity of the air gap magnetic flux density according to the deflection angle.

Since the dimensional accuracy of the facing surfaces of the yoke 11 and the core 12 that form the air gap 1113 can be improved, the uniformity of the air gap magnetic flux density corresponding to the deflection angle of the coil is better than in the conventional example, and the linearity of the indication is improved.

(3) Downsizing Since the magnet 14 is made thinner, it can be made smaller.

- For example, the outer diameter can be reduced by about 20% or more compared to the conventional example.

(4) The prices of the yoke 11 and the core 12 are reduced.

A simple cylindrical yoke 11 whose inner surface has only a cylindrical inner surface
and a simple cylindrical core 1 whose outer surface has only a cylindrical outer surface.
2, it is possible to use relatively inexpensive drawn materials with high dimensional accuracy.

Therefore, a product with good dimensional accuracy and low cost can be obtained.

(5) Dimensional accuracy of yoke 11 and core 12.

Since a drawn material with high dimensional accuracy can be used, products with high dimensional accuracy can be obtained.

Therefore, in order to manufacture a movable ring type wide-angle meter with an accuracy of ±1%, there is no need to create a scale plate with a scale for each piece as in the conventional example, and it can be manufactured at a low cost.

(6) Adjusting the length of magnet 4.

Since the yoke 11 and the core 12 are made of drawn material with high dimensional accuracy, the gap 13 also has high dimensional accuracy, and the magnet 14 only needs to be prepared with one type of magnet 14, unlike the conventional example. There is no need to prepare two or three types of magnets of different lengths, and costs can be reduced.

(7) Adjustment of thickness H of yoke 11 and core 12.

Since the yoke 11 and the core 12 are made of drawn material, the thickness H of the yoke 11 and the core 12 can be easily obtained with high dimensional accuracy.

It is particularly suitable for tote band type instruments.

(8) Relationship with demagnetization characteristic curve.

In the embodiment of FIG. 1, for example, when the deflection angle is 250 degrees, the permeance coefficient B/H is approximately 6.0.

As shown in FIG. 7, the operating point of the magnet is the intersection of the straight line OP with the permeance coefficient B/H=6.0 and the curves III, ■, ■, ■, and v in the demagnetization characteristic curve.

Here, curve I is an alnico-based cast magnet, curve ■ is a strontium ferrite magnet, and curve ■ is an iron, chromium,
Cobalt magnet, curve ■ is rare earth cobalt magnet, song w1
v indicates a demagnetization characteristic curve of a rare earth iron magnet.

Even if a magnet with curve I, which is the demagnetization characteristic curve of the strongest material among alnico cast magnets, is used, if the structure of this example is adopted, the air gap magnetic flux density will be about 15% lower than the conventional example shown in Figure 13. .

FIG. 8 is an explanatory diagram of the main part configuration of another embodiment of the present invention, and FIG. 9 is a side view of FIG. 8.

In this embodiment, 14A is a magnet formed such that both ends thereof are parallel to the direction of magnetization.

In the example shown in FIG. 1, the leakage flux near both ends of the magnet was large, and the error in linearity of the scale was large.

10 and 11, which is an enlarged view of FIG. 10.
As shown in the figure, the magnet I4 is magnetized parallel to the magnetization direction y-Y'', and the fluxes B and B2 come out from the end face AB of the magnet.
is added to the magnetic fluxes c and C2 that originally pass from the core 12 to the yoke 11, and as a result, the uniformity of the air gap magnetic flux density is impaired, and as a result, it is thought that the error in the linearity of the scale characteristics becomes large. In this embodiment, as shown in FIG.
Both end faces in contact with the air W113 of 4A are formed parallel to the magnetization direction of the magnet to reduce local leakage flux at the end of the magnet as shown in FIG.

As a result, the uniformity of the air gap magnetic flux density was improved, and errors in the linearity of the scale characteristics were reduced.

That is, the linearity of the scale characteristics was improved. -For example, the maximum value of the error of the scale characteristic is as shown in Fig. 13.
It decreased from about -3% to about -1%.

<Effects of the Invention> As explained above, the present invention provides (1) a movable ring type wide-angle instrument in which a core and a yoke are arranged concentrically with a gap therebetween; A movable ring type wide-angle instrument comprising: a yoke; and a tile-shaped rare earth magnet placed in the gap.

(2) A movable ring type wide-angle instrument according to claim 1 is constructed, wherein both ends of the magnet are formed parallel to the direction of magnetic flux.

As a result, (1) The concentricity of the yoke and core can be easily adjusted.

A void is formed only by a cylindrical yoke made of drawn material and having only a cylindrical inner surface, and a cylindrical core whose outer surface has only a cylindrical outer surface.

Since a tile-shaped magnet made of a portion of the cylinder was inserted once into this gap and joined, highly accurate concentricity can be easily obtained and position adjustment becomes easy.

In machining, when a part is machined into a cylindrical shape, it is generally possible to obtain a product with higher dimensional accuracy than when machining a part that has a partially flat surface. That is, it is relatively easy to manufacture each component concentrically in a cylindrical shape with high precision.

Therefore, the position adjustment is easier than in the conventional example in which the surfaces of the yoke and the core with respect to the gap have to be cylindrical, and the joints with the magnet have to be flat.

(2) Improving the uniformity of the air gap magnetic flux density according to the deflection angle.

Since the dimensional accuracy of the facing surfaces of the yoke and core that form the air gap can be improved, the uniformity of the air gap magnetic flux density corresponding to the deflection angle of the coil is better than in the conventional example, and the linearity of the scale characteristics is improved.

(3) Downsizing Since the magnet can be made thinner, it can be made smaller.

As an example, the size can be reduced by about 20% or more compared to the conventional example.

(4) The price of the yoke and core becomes cheaper.

A simple cylindrical yoke whose inner surface has only a cylindrical inner surface,
Since it consists of a simple cylindrical core with only a cylindrical outer surface, high dimensional accuracy can be obtained and inexpensive drawn materials can be used.

Therefore, a product with good dimensional accuracy and low cost can be obtained.

(5) Dimensional accuracy of yoke and core.

Since a drawn material with high dimensional accuracy can be used, products with high dimensional accuracy can be obtained.

Therefore, in order to manufacture a movable ring type wide-angle instrument with an accuracy of 1%, there is no need to create a scale plate with a scale for each piece as in the conventional example, but it is possible to use a pre-printed scale plate. It can be made cheaply.

(6) Adjustment of magnet length.

Since the yoke and core are made of drawn material with high dimensional accuracy, the gap also has high dimensional accuracy, and the magnet also
It is sufficient to prepare almost one type of magnet, and there is no need to prepare two or three types of magnets with different lengths as in the conventional example, which can reduce costs.

(7) Adjustment of yoke and core thickness.

Since the yoke and core are made of drawn material, it is easy to obtain products with high dimensional accuracy. It is particularly suitable for tote band type instruments.

(8) Relationship with demagnetization characteristic curve.

The operating point of the magnet is the intersection of the straight line with a constant permeance coefficient B/H and the demagnetization characteristic curves of various magnets in the demagnetization characteristic curve.

Even if a magnet having the demagnetization characteristic curve of the material with the strongest coercive force among Alnico cast magnets is used, when the structure of the present invention is adopted, the air gap magnetic flux density will be about 15% lower than that of the conventional example.

Furthermore, according to the movable ring type wide-angle instrument described in claim 2, by forming both end surfaces in contact with the gap of the magnet in the same direction as the magnetization of the magnet, leakage flux generated from the end of the magnet can be reduced. It has been reduced.

As a result, the uniformity of the air gap magnetic flux density was improved and the linearity error of the scale was reduced.

That is, the linearity of the scale characteristics was improved. - For example, the maximum error of the scale characteristic is about -3% to about -1%.
decreased to

Therefore, according to the present invention, it is possible to realize a movable ring type wide-angle instrument that has good linearity of scale characteristics, is easy to manufacture, and can be made compact.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the main part configuration of an embodiment of the present invention, Fig. 2 is a side view of Fig. 1, Fig. 3 is a detailed view of the main part of Fig. 1, and Fig. 4 is a side view of Fig. 3. Fig. 5 is an installation view of Fig. 1 with the movable part attached, Fig. 6 is a side view of Fig. 5, Fig. 7 is an explanatory diagram of the operation of Fig. 1, and Fig. 8 is an illustration of another embodiment of the present invention. 9 is a side view of FIG. 8, FIG. 10 is an explanatory diagram of the operation of FIG. 8, FIG. 11 is a detailed view of the main part of FIG. 10, FIG.
13 is an explanatory diagram of the operation of FIG. 8, FIG. 14 is an explanatory diagram of the configuration of a conventional example commonly used, and FIG. 15 is a side view of FIG. 14. DESCRIPTION OF SYMBOLS 11... Yoke 1, 12... Core, 13... Gap part, 14. 14A... Magnet, 15... Adhesion, 21.
22...Flange, 31...Movable part, 32.33.
...Support frame. ＼：＋５・□′ 8th 0th figure 1st figure 2nd figure 3rd 1st

Claims (2)

[Claims] (1) In a movable linear wide-angle instrument in which a core and a yoke are arranged concentrically with a gap between them, the core and yoke are made of soft pipe-shaped drawn material, and a tile-shaped rare earth magnet is placed in the gap. A movable linear wide-angle instrument characterized by comprising: (2) The movable linear wide-angle instrument according to claim 1, wherein both ends of the magnet are formed so as to be parallel to the direction of magnetization.