JPH0276206A - Plunger-type electromagnet iron core - Google Patents

Abstract

PURPOSE:To increase sensitivity of an electric magnet by forming the surface of a magnetic pole in the terraced shape on a plunger side by piling up the plural number of cone trapezoids on the same axis as the plunger and on a fixed iron core side in the shape having a recessed section with many stages which fit in the plunger with a little space in between. CONSTITUTION:The surface of a magnetic pole where a fixed iron core 2a and a plunger 3a are attracted and separated is formed by piling up two cone trapezoids, whose height p equals to a moving distance q of the plunger 3a and which have different diameters, on the side of the plunger 3a and by making a two-staged recessed section which fits in the plunger 3a with a little space in between on the side of the fixed iron core 2a. When the fixed iron core 2a and the plunger 3a are engaged with each other, the movement of the plunger 3a is smooth since there is a little space between the slanted side of the cone trapezoids and the recessed section of the fixed iron core 2a. By this method, the suction force against the same input is increased and a higher sensitivity is achieved.

Description

[Detailed description of the invention] [Industrial application field] Is this invention a plunger type? ! Regarding Hi stone iron core.

More specifically, the present invention relates to a technique for increasing the sensitivity of a plunger-type electromagnet by improving the shape of the AII surface on which the plunger and fixed core are attached and detached.

[Prior Art 1] A plunger type electromagnet conventionally used in electromagnetic valves for gas appliances will be explained with reference to FIG.

Note that FIG. 6(a) is a cross-sectional view, and FIG. 6(b) is a cross-sectional view of FIG.
Fig. 3a) shows a right side view of a). As shown in Figure 6? !
The tm stone includes a yoke l, a fixed iron core 2 fixed to the yoke l, a plunger 3 that abuts the fixed iron core 2, a spring 4 that separates the fixed iron core 2 and the plunger 3 by a predetermined distance, and the plunger 3. A circuit consisting of a guide vibro that guides the operation, a fixed iron core 2, a plunger 3, and a yaw l is magnetized by energization, and the plunger 3 is attracted to the fixed iron core 2 against the biasing force of a spring 4. It is composed of a coil 5 and the like.

[Problem to be Solved by the Invention 1 The above-mentioned plunger R2M stone is used in various fields including solenoid valves for gas appliances due to its ease of handling and low cost. Various requests have been submitted by users, but in particular, there is a demand for higher sensitivity of electromagnets, that is, for electromagnets of the same size but requiring less power.

The inventor Go has been conducting intensive research on increasing the sensitivity of electromagnets, and the applicant has already applied for utility model registration (August 1988).
March 30) [We are proposing a highly sensitive plunger type electromagnet J.

However, the shape of the magnetic pole surface on which the plunger and fixed iron core are attached and detached in the prior art described above is as shown in FIGS. 5(a) and 5(b).
It is configured in the shape shown in . With such a shape, when the plunger 3 is attracted to the fixed iron core 2, there is a problem that the differential coefficient of the permeance in the operating direction of the plunger 3 is small when the plunger 3 is activated.

The present invention focuses on the shape of the magnetic pole surface on which the plunger 3 and the fixed iron core 2 are attached and detached, and uses the shape to increase the differential coefficient, thereby increasing the sensitivity of the electromagnet. The objective of this project is to provide an electromagnet core with even higher sensitivity and to meet the needs of UNISER.

[Means for Solving the Problems 1] The present invention solves the above-mentioned problems, and employs the following technical means. In other words, the magnetic pole surface of the plunger-type electromagnet that attaches and detaches between the plunger and the fixed core is made of a plurality of truncated conical shapes stacked on the same axis as the plunger on the plunger side in a tapered step shape, and on the fixed core side the plunger It is formed from multi-step recesses that loosely fit into each truncated cone and lock with the plunger side.

Further, a suction vane plate, which faces the yoke end face of the electromagnet perpendicular to the plunger axial direction of the electromagnet and has a facing plane larger than the outer diameter of the plunger, is installed at the end of the plunger opposite to the fixed iron core. It is even more effective if it is installed across a working distance of .

[Action J Generally, the attractive force of an electromagnet is expressed by the following equation.

Here, F: Suction power U: Excitation ampere turn P: 1itl road permeance X: Empty direction of plunger operation Gap length It is.

FIG. 1 is a partially cross-sectional explanatory diagram of an embodiment of the present invention.

Comparing Figure 1 with Figures 5(a) and 5(b), 1
In the present invention, since the magnetic pole surface on which the plunger 3a and the fixed iron core 2a are attached and detached is configured in multiple stages, the plunger 3a
The differential coefficient of the permeance P with respect to X at the illustrated position fΔX) between a and the fixed iron core 28 is larger in the present invention, and therefore a large attraction force F can be obtained with the same excitation ampere turn U.

Next, the action of the suction vanes will be explained. As shown in FIG. 6(a), the conventional plunger type electromagnet requires a non-magnetic gap of d between the surfaces of the yoke 1 and the plunger 3, and the permeance PD of this part is well-known. It is expressed by the following formula.

PD, Misaki K 1td t/d +...-(1)
Here, d...the outer diameter L of the plunger...the yoke thickness...by providing the proportional constant suction vane plate 7, as shown in Fig. 3,
The permeance PDL between the yoke l and the suction vane plate 7 is:

P D L # is represented by π(D”-d”)/L (2).

Here, D... Outer diameter of suction vane plate L...Distance between the suction vane and the yoke d is the same as equation (1). Usually, D=2d~3d L=4d, ~lod.

If we select design values for D = 3d, L' = 5d, binding, and d = 5mm and d + = 0.5mm, then L = 2.5 mm, and the above (1) and ( 2
) From the formula, PDI/PDL= (9d"-d")15dt=1.6
If d/l is ko8/l and t=1mm.

PD, /PDL=8, that is, by providing the suction vane, the permeance between the yoke and the plunger is significantly improved.

〔Example〕

FIG. 1 is a detailed explanatory diagram of the present invention, showing the shape of the magnetic pole surface on which the fixed iron core 2a and the plunger 3a are attached and detached.In this embodiment, the height p on the plunger 3a side is Two truncated cones with diameters different from each other and which are equal to the working distance q of the plunger 3a are configured in a stepped manner, and the fixed iron core 2''a side is loosely fitted into each truncated cone shape on the plunger 3a side. In other words, when the fixed iron core 2a and the plunger 3a are locked, a minute gap is provided between the opposing truncated conical inclined side parts, and the plunger is locked. This allows the jar 3a to operate smoothly.

FIG. 2 shows a dimensional drawing of an embodiment of the invention.

Next, a specific example of the present invention will be explained with reference to FIGS. 3 and 4. FIG. 3(a) is a partial sectional view of another embodiment of the present invention, FIG. 3(b) is a right side view of FIG. 3(a), and FIG. 4 is a diagram of the electromagnet of the present invention and a conventional example. This is a graph comparing the relationship between input and attraction force.

As shown in FIGS. 3(a) and 3(b), a yoke 1 perpendicular to the operating axis of the plunger 3a is provided at the end opposite to the fixed iron core 2a surface to which the end surface of the plunger 3a is attached/desorbed.
A suction vane plate 7 is mounted parallel to the end face of the yoke l, facing the end face. Further, the outer diameter of the suction vane plate 7 is configured to be larger than the outer diameter of the plunger 3a, and the suction vane plate 7
and the yoke l are maintained at equal intervals to the working distance q of the plunger 3a.

A in the graph shown in FIG. 4 uses the N-marked iron core shown in FIG. 3. B is the data of the previously proposed electromagnetic core, and C is the data of the commercially available product. As is clear from FIG. 4, it can be seen that in the present invention, the suction force is significantly increased for the same human power.

In the embodiment shown in FIG. 3, the attachment parts are fitted and fixed to the suction vane 7 and the plunger 3a, but as shown in the earlier application,
If the suction vane plate 7 is loosely fitted into the plunger 3a so that it can be slightly oscillated, the manufacturing accuracy between the plunger 3a, the fixed iron core 2a, and the yoke 1 may be reduced (reducing the manufacturing cost of the ?tf magnet. can be achieved.

"Effect of the invention] The present invention has the following extremely excellent effects.

(2) It has a simple structure and can exhibit high sensitivity characteristics that are twice as high as those of the conventional method, and the effect is particularly remarkable when the working distance is 2 mm or more.

■The holding current of the plunger when the coil is energized is significantly reduced compared to conventional electromagnets of the same size, so it can be widely used in electromagnetic core applications such as those driven by battery power.

[Brief explanation of the drawing]

Detailed explanatory drawings of the present invention are shown in FIGS. 1 to 3, in which FIG. 1 is a partial sectional view, FIG. 2 is a dimensional drawing of an embodiment, FIG. 3 is another embodiment, and FIG. Figure (a) is a partial view, Figure 3 (b)
) is a right side view of Fig. 3(a), Fig. 4 is a graph comparing the relationship between electromagnet input and attraction force for the present invention and the conventional example, and Fig. 5 shows the relationship between the plunger and fixed iron core of the conventional example. FIG. 6 is an explanatory diagram of a magnetic pole surface to be attached and detached, and FIG. 6 is an explanatory diagram of a conventional electromagnet. l...-Yoke 2.2a... Fixed core 3.
3a...Plunger 4...Spring 5...Coil 6...Guide pipe 7...Suction vane plate d2, t, p, q...
Distance eight Yoshio Kosugi Figure 1 Figure 2 Figure 4 (a) (b) Figure 5 Figure 6 (b) Figure

Claims (1)

[Scope of Claims] 1. The magnetic pole surface of the plunger-type electromagnet that attaches to and detaches from the plunger of the fixed iron core is such that the plunger side has a plurality of truncated conical shapes stacked in a tapered step-like manner coaxially with the plunger. A plunger-type electromagnetic core, characterized in that the fixed core side is formed with multi-stage recesses that loosely fit into each truncated cone of the plunger and lock with the plunger side. 2. At the end of the plunger opposite to the fixed iron core, a suction blade that faces a yoke end surface of the electromagnet perpendicular to the axial direction of the electromagnet and has an opposing plane larger than the outer diameter of the plunger. The plunger type electromagnetic core according to claim 1, wherein the plate is attached across the working distance of the plunger.