JPS5825124Y2 - Electromagnetic nozzle flapper - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an electromagnetic nozzle flapper that can electrically control fluid pressure in a fluid circuit.

In general, electromagnetic nozzle flappers control pressure in the fluid circuit.
Widely used as a flow rate control element.

As illustrated in FIG. 1, the prior art has a nozzle 2 at the tip of a pipe 1 through which fluid flows, and a throttle 3 inside.
is provided, and a side pipe 4 is connected from the middle between the nozzle 2 and the aperture 3.

A flapper 5 provided close to and facing the nozzle 2 is rotatably supported via a shaft 6, and an electromagnet 7 serving as an electromagnetic drive unit is provided adjacent to the flapper 5 with a gap δ maintained therebetween. .

The void δ indicates the sum of the voids at two locations. In the electromagnetic nozzle flapper configured in this way, the required fluid control pressure is precisely obtained from the side pipe 4 by finely adjusting the gap δ. Since this can only be obtained when the electromagnet 7 and the flapper 5 are operated, the assembly, operation, and disassembly of the electromagnet 7 and the flapper 5 are repeated, and the shape of the flapper is adjusted to match the surface of the nozzle 2 and the gap δ. In manufacturing situations, it takes a long time to make various adjustments such as creating an optimal shape for both, and there are difficulties in terms of stability of performance of electromagnetic nozzle flappers and productivity in terms of manufacturing and maintenance.

To explain this situation in more detail, in an electromagnetic nozzle flapper, the magnetic attraction force of the flapper and the fluid pressure (repulsion force caused by this) are expressed by the following equation.

Fm - KBgSg F p = P S n where Fm is the magnetic attraction force of the flapper 5 due to the electromagnet 7, K is a constant, Bg is the magnetic flux density of the air gap δ, Sg is the cross-sectional area of the air gap δ, and Fp is the flapper force due to fluid pressure. 5 separation force, P
represents the fluid pressure of the nozzle 2, and Sn represents the nozzle cross-sectional area.

That is, by controlling the pressure of the fluid ejected to the nozzle 2 through the aperture 3 to a constant value, the pressure in the valve chamber passing through the side pipe 4 (the pressure in the valve chamber, etc. that flows through the side pipe 4) can be controlled by controlling the clockwise direction by the magnetic attraction Fm of the flapper 5 caused by the electromagnet 7. The magnetic flux density Bg of the air gap δ may be adjusted by the control current of the electromagnet 7 or the air gap δ so that the rotation force and the counterclockwise rotation force of the repulsion force Fp of the flapper 5 caused by the fluid pressure P are balanced. .

A power supply controller (not shown) is provided to supply a control current for the electromagnet 7 according to the requirements of the control range of the fluid pressure normally used, but one type of power supply controller (not shown) is used for various requirements. .

Therefore, the maximum value of the required fluid control pressure corresponds to the maximum control current of the power supply controller, but even if the fluid control pressure actually used is low, it is easy to accurately set the corresponding control current. We manufacture various electromagnetic nozzle flappers that allow you to select various fluid control pressures for the same control current.

This example is shown in FIG. FIG. 2 is a diagram illustrating the relationship between fluid control pressure and control current.

In FIG. 2, the vertical axis shows the fluid control pressure, and the horizontal axis shows the control current.

Characteristics A, B, and C straight lines have air gaps δ selected as δ□, δ2, and δ3, respectively, and a maximum control current of 400 mAG, corresponding to a maximum control pressure cuff of 0, 140, and 210 Ky/cr1.
．． It was designed to obtain

For example, when a control pressure of 3 sKq/crd is required, the corresponding control current is 66 on the characteristic C2B and A straight lines.
mA, 100 mA, and 200 mA, the fluid control pressure changes gradually become more rapid with respect to changes in the control current at these points, and the setting becomes easier.

Therefore, the air gap δ0 corresponds to a maximum control current of 400 mA.
．． Maximum fluid pressure 70, 140 and 210 with δ value δ3
We manufacture three types of electromagnetic nozzle flappers with KV/cr/l, and choose one that meets the customer's fluid pressure requirements from among these three types.

In manufacturing the electromagnetic nozzle flapper, regarding the gap δ between the electromagnet I and the flapper 5 in FIG. 1, the gap δ□′, 62 is set at a design value such that the characteristics A, B, and C straight lines shown in FIG. 2 are shown at the time of manufacturing and assembly, respectively. ' and 63', but when the electromagnetic nozzle flapper is actually operated, the maximum control pressure cuffs 0, 140 and 210 show 9/cr/l for the electromagnet's control current of 400 mA. Therefore, it becomes necessary to further finely adjust the gaps δ□', 62', and 68', which are originally minute.

This is because when considering the case where a large number of electromagnetic nozzle flappers are connected to a power supply controller, a variable resistor, for example, should be installed in each electromagnetic nozzle flapper to finely adjust its control current, but the electromagnetic nozzle flapper This is because, considering that the device is used in a fluid, a variable resistor for finely adjusting the control current is not installed because the structure becomes complicated.

Therefore, in order to create an appropriate air gap δ, it is necessary to repeatedly assemble, operate, and disassemble the relative positions of the electromagnet 7 and the flapper 5, and to adjust the shape of the flapper 5 in various ways so as to fit both the surface of the nozzle 2 and the air gap δ. It takes a long time to make adjustments, such as creating an optimal shape.

This idea is based on the fact that it takes a long time to finely adjust the magnetic flux density of the main magnetic circuit consisting of the electromagnet 7 and the flapper 5, which are electromagnetic drive parts, by changing the air gap δ. Fine adjustment of the magnetic flux density of the main magnetic circuit can be achieved by making the air gap with the flapper 5 one, and by providing a parallel magnetic side path with a high magnetic variable resistance in the main magnetic circuit, or by providing a low magnetic variable resistance in series. To provide an electromagnetic nozzle flapper having a simple structure and having a magnetic short circuit secondary circuit that can be easily finely adjusted from the outside, from the viewpoint of short-time operation.

Next, an embodiment of the electromagnetic nozzle flapper of this invention will be described.

In FIG. 3, a fluid-tight case 10 is made of non-magnetic material to avoid the influence of external magnetic fields, and through holes 11 and 12 are bored in one side wall.

An electromagnet 13, which is an electromagnetic drive unit installed inside the case 10, includes a cylindrical T-shaped core 14, a plate-shaped yoke 15 having a U-shaped cross section, a winding frame 20 to which the T-shaped core 14 is attached, and It includes an excitation winding 19 wound around this winding frame 20 and the like.

The lower end of the T-shaped core 14 is fluid-tightly inserted and fixed into a through hole 18 drilled in the yoke 15 and a through hole 11 in the case 10, for example, and is connected to an external conduit ( (not shown).

A nozzle 24 is formed at the upper tip of the T-shaped core 14,
A flapper 23 is provided close to and opposite this nozzle 24.

The base end of the flapper 23 is connected to the leg 1 at one end G of the yoke 15.
6 is rotatably supported via a pin 22, and a coil spring 21 is stretched between the intermediate portion and the protruding portion of the leg portion 16.

In addition, a ferromagnetic material is installed in a shape that is opposed to the tip 26 of the leg portion 17 at the other end of the yoke 15 and the shoulder portion 25 of the T-shaped core 14, and that extends through the case 10 and is adjustable from the outside by, for example, a screw drive. A short circuit 27 is attached.

In addition, in order to limit the adsorption force when the flapper and nozzle are in contact, or to prevent iron powder from adhering to the nozzle and the part of the flapper facing the nozzle, T
It is desirable that the tip nozzle portion of the shaped iron core 14 and the portion of the flapper facing the nozzle be made of a non-magnetic material.

In this invention constructed as described above, the electromagnetic nozzle flapper is actuated to connect the short circuit 27 to the shoulder 2 of the T-shaped core 14.
5 and the tip 26 of the leg 17 by a small distance from the screw drive O, the magnetic flux density of the secondary short circuit consisting of the T-shaped core 14, the short circuit 27, the leg 17, and the yoke 15 can be reduced. By changing the flapper 23, T
It is required to finely adjust the magnetic flux density in the main magnetic circuit composed of the shaped iron core 14, the yoke 15, and the legs 16, and to have the same effect as when finely adjusting the air gap δ4 between the nozzle 24 and the flapper 23. Accurately obtain fluid control pressure.

For example, if an electromagnetic nozzle flapper with the characteristic C straight line shown in Fig. 2 is required, the air gap δ4 is adjusted and assembled in advance to the air gap δ2 so that the maximum control pressure is 210, slightly higher than 7/m. By adjusting the short circuit 27, the control pressure is accurately set to 21°K57/m+.

In addition, if an electromagnetic nozzle flapper with characteristic B straight line is required, the gap δ4 portion should be preset at a maximum control pressure of 14
oKti/c1. The control pressure is accurately set to 14 oKp/C1ft by adjusting and assembling the air gap δl to make it higher, and adjusting the short circuit 27.

In addition, if an electromagnetic nozzle flapper with a characteristic A straight line is required (in this case, the maximum profit pressure is set accurately to 7oKy/7 in exactly the same way.

That is, the magnetic flux flowing through the electromagnet 13 has the following relationship.

φ2φδ3′−φC φ−φδ2″−φ′ φ−φδ,′−φ′ Here, φC5φB and φ6 are the magnetic fluxes passing through the nozzle flapper in the characteristic C, B, and A straight lines.

Also, φδ3', φδ2' and φδ,' are air gaps δ3', 6
2′ and δ□′ are the magnetic fluxes passing through the nozzle flapper.

Also φ.

', φI and φ have the characteristic 0. This is the magnetic flux passing through the nozzle flapper that was reduced by fine adjustment of the secondary short circuit in the B and A straight lines.

According to this idea, as mentioned above, after assembling the nozzle flapper gap with a predetermined approximate value in the production process,
Since minute adjustments can be easily made from the outside without disassembling or adding objects directly to the nozzle flapper, only one model is needed for production, which is superior in terms of stable performance, improved productivity, and improved serviceability. This has the advantage of providing an electromagnetic nozzle flapper.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing an example of a conventional electromagnetic nozzle flapper, Fig. 2 is a diagram illustrating the relationship between fluid pressure and control current, and Fig. 3 is an example of the electromagnetic nozzle flapper of this invention. FIG. 13... Electromagnet, 14... T-type iron core,
15... Yoke, 19... Excitation winding, 20
...Reel frame, 23...Flapper 24.
... Nozzle, 27 ... Short circuit.

Claims (1)

[Scope of utility model registration request] An electromagnetic nozzle flapper having a nozzle from which fluid is ejected, a flapper rotatably supported in close proximity to the nozzle, and an electromagnetic drive unit that applies an attractive force to the flapper in a direction in which the nozzle approaches the nozzle, An electromagnetic nozzle flapper comprising a magnetic short-circuit secondary circuit equipped with a magnetic flux adjustment mechanism in the electromagnetic drive section.