JP2832757B2 - Device for inserting metallic sodium into hollow valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insertion device for improving the insertability of metallic sodium into a hollow hole when solid metallic sodium is inserted into a hollow valve for an internal combustion engine.

[0002]

2. Description of the Related Art A hollow valve is very advantageous in reducing the weight of a valve body and reducing the inertial mass of a valve train. In this type of hollow valve, there is a hollow valve in which metallic sodium as a cooling medium is sealed in a hollow hole formed from an umbrella to a stem to improve the cooling performance of the umbrella.
(See, for example, JP-A-58-185917).

[0003] When metal sodium is inserted into such a hollow valve, conventionally, for example, an apparatus as shown in Figs. 3 and 4 is used.

That is, a cylinder fixed to a base (1)
(2) is filled with solid metallic sodium (3) at room temperature, and then piston rod is placed from above cylinder (2).
By pressing (4), solid metallic sodium (3)
Is compressed and extruded from a nozzle (5) provided at a lower portion of the cylinder (2) to form a rod (8) having a diameter slightly smaller than the hollow hole (7) of the hollow valve (6) shown in FIG.

Then, the rod-shaped body (8) is formed to have an appropriate length determined based on the length of the hollow hole (7), for example, approximately ／ of the length of the hollow hole (7). Then, it is cut by the cutter (9).

Then, as shown in FIG. 4, a rod-shaped body (8) of metallic sodium cut to an appropriate length is gripped by a suitable gripping means (10) such as tweezers to form a hollow valve (6). Insert from the upper open end into the hollow hole (7).

[0007] Finally, the opening is closed by a terminal member (not shown), and a rod-shaped body (8) of metallic sodium is sealed in the hollow hole (7).

[0008] The hollow valve (6) thus manufactured is
The rod-shaped body (8) of metallic sodium is melted into a liquid by the combustion temperature when mounted on the engine, and the heat of the umbrella (11) is quickly transmitted to the stem (12) side using this as a heat transfer medium. Then, heat can be radiated to the cylinder head (both not shown) through the valve guide.

[0009]

At ordinary temperature, metallic sodium is in the form of a soft solid, that is, a clay-like material, and has the property of rapidly oxidizing when exposed to air and becoming more viscous.

Therefore, as in the above-described conventional device,
The metal sodium (3) filled in the cylinder (2) is extruded at room temperature to form a rod (8), which is
When shearing at (9), the rod-shaped body (8) bends to one side during shearing, burrs are formed on the cut, and the cross-section does not become circular, or the rod-shaped body (8) after cutting adheres to the cutter (9). Or you may.

In this case, it takes time and effort to insert the rod-shaped body (8) cut into a predetermined length into the hollow hole (7) of the hollow valve (6), and the productivity is remarkably reduced. In particular, when the insertion process is automated, the insertion cannot be performed unless the hollow hole (7) and the rod-shaped body (8) are always aligned on the same axis. Need to be completely prevented.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to prevent bending or burrs from occurring in a rod-shaped metallic sodium to thereby prevent the hollow valve from being hollow. Improve the insertion into the hole,
An object of the present invention is to provide a metal sodium insertion device capable of significantly increasing productivity.

[0013]

According to an aspect of the present invention, there is provided an apparatus for ejecting a cooling medium on an inner surface of a guide hole through which a rod-shaped metallic sodium extruded from a nozzle passes. The cooling device is provided at the opening of the nozzle for extruding metallic sodium.

[0014]

The rod-shaped metal sodium extruded from the nozzle passes through the guide hole of the cooling device provided in the opening of the nozzle, and the cooling medium (liquid nitrogen) flowing out of the ejection hole on the inner surface of the guide hole. ), The solidification and cooling of the rod-shaped body can be prevented.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. The same members as those in the conventional example described above are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 1 shows a first embodiment of the present invention. A solid metal sodium (3) filled in a cylinder (2) at room temperature is provided at a lower end surface of a cylinder (2). (13) having an extruded hole (13a) for extruding a rod as a rod (8), and a rod at the center fitted to the lower end face thereof.
A cooling device (14) having a large-diameter guide hole (14a) through which (8) can easily pass and a small-diameter guide hole (14b) connected to the lower end thereof.
Are fixed to the cylinder (2) with bolts (15) so that the central axes of the two are aligned.

The guide hole (14b) in the cooling device (14)
The rod has a slightly larger diameter than the extrusion hole (13a), and the upper end connected to the large-diameter guide hole (14a) has an inverted U-shaped tapered surface to enter the guide hole (14b) of the rod-shaped body (8). In addition, the cooling medium described later is made to easily flow into the guide hole (14b).

Around the guide hole (14a) in the cooling device (14),
An empty space (16) having a required volume is formed, and the empty space (16) and the large-diameter guide hole (14a) are
It is communicated with 7).

Liquid nitrogen (19) as a cooling medium sent through a pipe (18) attached to the outer peripheral surface of the cooling device (14) is supplied into the vacant space (16). ing.

In the apparatus of the above embodiment, the piston rod (4) is depressed, and the metallic sodium in the cylinder (2) is depressed.
When (3) is compressed, the metallic sodium (3) becomes
It is extruded into a rod (8) having a predetermined diameter through the extrusion hole (13a) of 3).

Next, the large-diameter guide hole (14) of the cooling device (14) is used.
While passing through a), the liquid nitrogen (1
9) is injected from a plurality of ejection holes (17) toward the rod-shaped body (8), whereby the rod-shaped body (8) is cooled and hardened to an appropriate temperature and hardness, and the guide hole (14b) is closed. It is pushed downward sequentially through.

Next, a hollow valve positioned just below the cooling device (14) so that the center axes thereof are aligned vertically.
Inserting the tip of a rod-shaped body (8) of metal sodium cooled and hardened into the hollow hole (7) of (6), and cutting it with a cutter (9) at a predetermined size, the rod-shaped body (8) becomes It falls under its own weight and is easily and automatically inserted into the hollow hole (7).

At this time, part of the liquid nitrogen (19) flowing into the large-diameter guide hole (14a) is transferred from the guide hole (14a) to the rod-shaped body (8).
Flows into the hollow (7) along the circumference of the hollow
In order to remove the air in the hollow hole (7) by evaporating into nitrogen gas in (7) to remove the air in the hollow hole (7), when the hollow hole (7) is closed in a subsequent step, the rod-shaped body (8) (metal sodium) Can be prevented from being oxidized.

The rod-shaped body (8) after being cooled and hardened is inserted into the hollow hole (7) by cutting the rod-shaped body (8) to a predetermined size and then by an appropriate gripping means as in the conventional case. The holding may be performed in another step, and in this case, there is no risk of impairing the insertability into the hollow hole (7).

Next, a second embodiment of the present invention will be described with reference to FIG. The cooling device (14) of the second embodiment has a large-diameter guide hole (2) similar to that of the first embodiment at the center of the device.
0a) and a cylindrical porous body (20) provided with a small-diameter guide hole (20b) connected thereto, and supplied to the outside of the outer peripheral surface thereof by a pipe (18) in the same manner as described above. Liquid nitrogen (19)
A closed vacant space (16) for storing the air is formed.

The rod-shaped body (8) of metallic sodium extruded by the nozzle body (13) forms a large-diameter guide hole (20) of the porous body (20).
a) When passing through the inside of the porous body (20), guide holes (20a)
The liquid nitrogen (19) flowing in small amounts to the side is cooled or hardened directly by liquid nitrogen (19) or indirectly by the heat of vaporization when the outflowing liquid nitrogen (19) evaporates, and it is below the guide hole (20b). Extruded.

In the second embodiment, the same functions and effects as those of the first embodiment can be obtained. In the second embodiment, the liquid nitrogen (19) in the empty space (16) is directly supplied to the porous body (20). 17).

As described above, in each of the first and second embodiments, the cooling device is supplied with the metallic sodium (3) having viscosity at room temperature immediately after it exits the nozzle body (13). (14)
As a result, the peripheral surface of the rod-shaped body (8) is prevented from being sticky, and the rod-shaped body (8) bends when cut by the cutter (9) and when inserted into the hollow hole (7). In addition, it is possible to prevent the rod-shaped body (8) after cutting from adhering to the cutter (9) and not dropping, and preventing burrs or the like from being generated on the cut surface.

As a result, insertion of the rod-shaped body (8) into the hollow hole (7) of the hollow valve (6) can be performed very easily and quickly.

The present invention is not limited to the above embodiments, but can take various forms. For example, in both of the above embodiments, the nozzle body (13) is provided as a separate body.
It is formed integrally at the lower end of (2), and the cooling device (1
4) may be provided.

An evaporator (not shown) for evaporating the liquid nitrogen (19) is provided at an appropriate position of the pipe (18), and an empty space of the cooling device (14) is provided.
A low-temperature vaporized nitrogen gas may be supplied into (16), and the cold air may cool and harden the rod-shaped body (8).

[0032]

According to the present invention, metallic sodium formed into a rod is cooled and hardened by a cooling device.
The occurrence of stickiness, bending, burrs at the time of cutting, and the like are prevented, and the insertability of the hollow valve into the hollow hole is significantly improved, so that productivity can be significantly increased.

[Brief description of the drawings]

FIG. 1 is a central longitudinal sectional front view showing a first embodiment of the apparatus of the present invention.

FIG. 2 is a longitudinal sectional front view of a main part showing a second embodiment of the present invention.

FIG. 3 is a central longitudinal sectional front view of a conventional device.

FIG. 4 is an explanatory view showing a procedure for inserting metallic sodium as a rod into the hollow hole of the hollow valve.

[Explanation of symbols]

(1) Base (2) Cylinder (3) Metallic sodium (4) Piston rod (6) Hollow valve (7) Hollow hole (8) Rod (9) Cutter (11) Head (12) Stem (13) Nozzle Body (13a) Extrusion hole (14) Cooling device (14a) Guide hole (14b) Guide hole (15) Bolt (16) Vacancy (17) Jet hole (18) Pipe (19) Liquid nitrogen
(Cooling medium) (20) Porous body (20a) Guide hole (20b) Guide hole

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F01L 3/14 F01L 3/24 F01L 3/02 F01L 3/20

Claims (3)

(57) [Claims] 1. A cooling device having an ejection hole for discharging a cooling medium on an inner surface of a guide hole through which a rod-shaped metal sodium extruded from a nozzle passes is provided at an opening of the metal sodium extrusion nozzle. Characteristic device for inserting sodium metal into hollow valve. 2. A rod-shaped metal nut is provided at the center of the cooling device.
Cylindrical porous body with a guide hole through which the
The apparatus for inserting metallic sodium into a hollow valve according to claim 1, wherein the outer peripheral surface is fitted so as to be in contact with the cooling medium . 3. The apparatus for inserting metallic sodium into a hollow valve according to claim 1, wherein the cooling medium is liquid nitrogen.