JPS5926575Y2 - AC electromagnet assembly for wet type directional valve with adjustable operating time - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of an AC electromagnet assembly for a wet type directional valve.

Wet-type electromagnets have a plunger that is activated by excitation and demagnetization and is moved in an oil-immersed state (see Figure 1), and the purpose is to ensure smooth operation and to prevent eddy current loss. A through slit is provided along the axial direction of the plunger to allow oil to move.

Conventional examples of such a structure include, for example, a plunger P with a relatively large slit (S) of the same cross section as shown in FIG.
Some examples include those described in Publication No. 45.

However, in the former case, the plunger operates smoothly, but in this type of electromagnet, it is extremely difficult to adjust the operating time due to the structure, and in the latter case, the cross section of the groove formed in the plunger itself has to be changed. It does not form an orifice (or aperture), but the end of a pin fixed to the cylinder is inserted into the groove to form an orifice and provide braking resistance, so it cannot be used under high pressure (e.g. 260 kg). /Cm, it is practically impossible to install the pin of the guide tube due to problems such as oil leakage from the part, and when manufacturing the electromagnet assembly, it is necessary to manufacture the pin and attach the pin to the guide tube. Since an extra step of attaching the product to the cylinder is required, there is a problem in that the cost of the product increases.

The purpose of this invention is to expand the uses of this type of electromagnet by creating an electromagnet with a simple structure that allows adjustment of operating time, which was previously considered difficult, without impairing the characteristics of wet type electromagnets. There is a particular thing.

The present invention provides a wet-type electromagnet assembly in which a fluid passage is formed in a plunger, in which the fluid passage is formed by a slit extending in the axial direction from one end of the plunger part way on the outer periphery of the plunger, and a slit partway from the other end of the plunger inside the plunger. a hole extending in the axial direction up to 1000 m, the slit and the hole communicating with an orifice that restricts the flow of fluid through the fluid passageway, and configured such that the orifice restricts fluid flowing from one end of the plunger through the fluid passageway. has been done.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 3, a plunger of an embodiment of an electromagnetic assembly according to the invention is shown.

In this embodiment, the fluid passage includes a blind hole 3 extending halfway in the axial direction from one end (lower end in the figure) of the plunger at the center of the plunger, and two slits 1 extending halfway from the other end at the outer periphery of the plunger. The bottom of the slit and the blind hole 3 communicate with each other through an orifice 2 that extends from the small hole.

When the plunger of this embodiment is used in the assembly shown in FIG. 1 with the slit facing upward, the coil a
When the plunger P moves toward the fixed iron core by energizing, the fluid between the plunger P and the fixed iron core tries to flow through the slit to the other end of the plunger, but the flow is prevented by the orifice 2. The constriction imposes a resistance on the plunger that is determined by the length and/or cross-sectional area of the orifice.

Therefore, the moving time of the plunger can also be adjusted by arbitrarily selecting the size of the cross-sectional area of the orifice.

Note that the number of orifices, slits, etc. may be two or more depending on the setting degree of the adjustment time.

According to the present invention, the number of slits or fluid passages provided in the plunger is preferably one, but if this increases eddy current loss, increase the number to a minimum of multiple slits to sufficiently absorb the eddy current loss. be able to.

According to the electromagnet assembly of the present invention, the following effects can be achieved compared to the conventional ones.

(a) It is possible to accurately adjust the operating time, which is considered to be the most difficult aspect of wet type electromagnets, with a simple structure.

(b) The device described in the above-mentioned Japanese Utility Model Publication No. 33-19145 is not practical for high pressures due to concerns about oil leakage, but the present invention can be implemented even at high pressures.

(c) Whereas the device described in the above-mentioned publication requires a large number of parts and a large number of processing man-hours, resulting in a high product cost, the present invention can reduce the cost of the product by reducing the number of parts and processing man-hours.

[Brief explanation of drawings]

Figure 1 is a sectional view of a conventional wet type electromagnet, Figures 2 A and B are side sectional views and top views of a plunger used in a conventional wet type electromagnet, and Figures 3 A and B are a wet type electromagnet of the present invention. FIG. 2 is a side sectional view and a top view showing an example of a plunger used in an electromagnet. P Nibranger, 1 Nisrit, 2 Niorifice, 3:
Blind hole.

Claims (1)

[Scope of utility model registration request] A ring-shaped coil, a plunger guide inserted and fixed into the coil, a fixed iron core fitted into one end of the plunger guide, and a plunger slidably fitted into the plunger guide. , in a wet type electromagnet assembly in which the plunger is provided with a fluid passage, the fluid passage includes a slit extending halfway in the axial direction from one end of the plunger on the outer periphery of the plunger, and a slit extending halfway in the axial direction from the other end of the plunger in the plunger. 1. An AC electromagnet assembly for a wet type directional valve, characterized in that the slit and the hole are in communication with each other through an orifice that restricts the flow of fluid through the fluid passage.