JPH0231769Y2 - - Google Patents

Description

[Detailed description of the invention] [Detailed description of the invention] (a) Industrial application field The present invention relates to an oil-immersed solenoid, and more specifically, the invention relates to an oil-immersed solenoid, and more specifically, a plunger rod is protruded from both ends of a plunger, and the protrusion is connected to a bearing part. The present invention relates to a solenoid supported by a plunger that allows oil to flow smoothly within the plunger guide.

(B) Prior Art A conventional oil-immersed solenoid in which a plunger rod protrudes from both ends of a plunger and the protruding portions are supported by bearings, as shown in Fig. 5, has one end of a plunger guide a. A fixed iron core b is fixed to the fixed iron core b, the other end is sealed with a stopper member c, a plunger d is movably inserted therein and filled with oil, a plunger rod e is made to protrude from both ends of the plunger, and one end of the fixed iron core b is fixed to the fixed iron core b. It is inserted into a hole j formed in , and supported by a bush g in the hole f, and the other end is supported by a bush j fitted in a hole h of a stopper member c.

By the way, in this type of oil-immersed solenoid, the volume of the space inside the hole h changes as the plunger rod e moves, so that the oil in that space can enter and exit from the outside or from the outside. There is a need to. For this purpose, a passage 1 is formed in the bush holder k supporting the bush j, or a slit is formed directly in the bush j to communicate the inside of the space with the interior of the plunger guide.

However, such conventional solenoids have a problem in that as the solenoid itself becomes smaller, the bushes themselves also become smaller, making machining extremely difficult. Additionally, oil only flows locally, resulting in poor circulation and often leading to malfunction of the solenoid.

(c) Problems to be solved by the invention The problem to be solved by the invention is to solve processing problems and poor oil circulation by forming an oil passage in the plunger rod itself.

(d) Means for solving the problem The present invention consists of a plunger that is movably inserted into a plunger guide having a fixed iron core attached to one end and filled with oil, and a plunger installed around the outer periphery of the plunger guide. In the solenoid, the plunger has an axial hole that extends through the plunger in the axial direction, and a plunger rod that protrudes from both ends of the plunger, and that both ends of the plunger rod are supported by bearing members. forming a radial hole extending in the radial direction on the outer circumference of the plunger, forming the plunger rod from a hollow tube, and fitting the hollow tube into the axial hole of the plunger;
The hollow tube is configured with a passage that communicates the interior with the radial hole of the plunger.

(E) Effect In the above technical means, when the coil is energized and the plunger is attracted to the fixed iron core, the plunger rod also moves toward the fixed iron core together with the plunger, so oil flows from one end of the plunger rod to the other end through the through hole. At the same time, it flows through the passage to the outer peripheral side of the plunger and to the opposite side of the fixed core of the plunger. Conversely, when the coil is de-energized and the plunger leaves the fixed iron core, the oil flows in the opposite direction to that described above.

(F) Embodiments Examples of the present invention will be described below with reference to the drawings.

In FIG. 1, an embodiment of an oil-immersed solenoid according to the present invention is shown. In the same figure, 1
is a plunger guide, 2 is a fixed iron core fixed to one end of the plunger guide, 3 is a stopper member fixed to the other end of the plunger guide, 4 is a coil provided on the outer periphery of the plunger guide, 5 is a yoke, and 6 is a plunger A movable iron core, that is, a plunger, is movably inserted into the guide; 7 is a plunger rod inserted and fixed into the plunger 6 so that both ends protrude; and 8 is one end of the plunger rod 7, which is provided in a hole 9 of the fixed iron core 2. A bushing 10 that slidably supports the plunger rod is a bush that is attached through a bush holder 12 in the hole 11 of the stopper member 3 and slidably supports the other end of the plunger rod.

A through hole 13 is formed in the plunger rod 7 and extends through the plunger rod 7 in the axial direction. As the plunger rod, a relatively thick hollow tube formed in advance may be used. The plunger 6 and the plunger rod 7 are formed with passages 14, 15 extending in the radial direction and communicating the through hole 13 with the outer periphery of the plunger. A notch 16 is formed at one end of the plunger rod 7 (the left end in the figure), as shown in detail in FIG. This notch 16 prevents communication between the through hole 13 and the external space G from being obstructed even when one end of the plunger rod 7 comes into contact with the spool S of the solenoid valve.

In the above configuration, when the coil 4 is not energized, the plunger 6 and the plunger rod 7
is the stopper member 3 due to the action of a spring or the like (not shown).
It's on the side. When the coil is energized, the plunger 6 and the plunger rod 7 are connected to the fixed iron core 2.
The left end of the plunger (in the figure) hits the fixed iron core and stops. When the plunger, etc. moves, the space between the plunger 6 and the stopper member 3 and the volume of the hole 11 in the stopper member 3 increase, so oil must flow into the space, but this oil mainly It flows from the opposite side of the plunger between the plunger and the plunger rod, and a part of it flows through the notch 16 and the through hole 13 to the hole 11.
It also flows rapidly into the space through the notch 16, the through hole 13, the passages 14, 15 and the gap between the plunger and the plunger guide. Further, the oil that has been present between the plunger 6 and the fixed iron core flows to the right side of the plunger 6 through the gap between the plunger and the plunger guide as described above. Therefore, the plunger etc. can be moved smoothly.

Next, when the coil 4 is de-energized, the plunger and plunger rod move toward the stopper member, but at this time the oil flows in the opposite direction to that described above.

In order to easily align the passage 14a of the plunger 6a with the through hole 15a of the plunger rod, an annular groove 18a is provided on the outer periphery of the plunger rod as shown in FIG. 19a may be provided. Furthermore,
As shown in FIG. 4, the outer periphery of the plunger may be provided with an axially extending groove 20b or, if one end of the plunger rod is closed with a ball 21b, a radially extending passage 22.

(g) Effects According to the present invention, a hollow tube is used as the plunger rod, and processing is simple because only a relatively large plunger and a passage extending in the radial direction are formed in the plunger rod. Further, the fluid passage (i in FIG. 5) that was conventionally provided in the fixed core can be omitted.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of an oil-immersed solenoid according to the present invention, FIG. 2 is an enlarged view of a part of FIG. 1,
3 and 4 are views showing modified examples of the plunger and the plunger rod, and FIG. 5 is a sectional view of a conventional oil-immersed solenoid. 1: Plunger guide, 2: Fixed core, 3: Stopper member, 4: Coil, 6: Plunger, 7:
Plunger rod, 13, 13a, 13b: Through hole, 14, 14a, 14b: Passage, 15, 15
a, 15b: Passage.

Claims (1)

[Scope of utility model registration request] A plunger having a fixed iron core attached to one end and movably inserted into a plunger guide filled with oil, a coil provided on the outer periphery of the plunger guide, and plunger rods protruding from both ends of the plunger. In the solenoid having a plunger rod, both ends of which are supported by bearing members, the plunger is formed with an axial hole passing through the plunger in the axial direction and a radial hole extending radially from the axial hole to the outer periphery of the plunger. and the plunger rod is formed of a hollow tube, the hollow tube is fitted into an axial hole of the plunger, and a passage is formed in the hollow tube that communicates the inside with the radial hole of the plunger. An oil-immersed solenoid featuring: