JPH02120576A - Plug device - Google Patents

Abstract

PURPOSE:To aim at improving a sealing and plugging function for the plugging member of the opening part in desirable operability regardless of thermal change and the press-in time to a main body by constructing a plug device, which is for plugging the opening part of a body, of the main body made of Al alloy and a ball made of a raw material with an approximately equal thermal expan sion coefficient and applying a hardening treatment to the ball. CONSTITUTION:In a plug device for plugging the pore end part bored in the main body of a pump device and the like, a main body 1 made of Al alloy and perforated, and a ball 3 made of a raw material with an approximately equal thermal expansion coefficient to the main body 1 and plugging in the pore part 2 of the main body 1 are provided; and hardening treatment (for instance, alumite treatment) is applied to the surface of the ball 3. The ball 3 is further secured in the end face opening part 2a of the pore 2 by drive fitting, so that the pore 2 plugged. The anxiety of chipping at a press-in time is thus dissolved and a sealing and plugging function is sufficiently provided regardless of thermal change.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a plug device for plugging the end of a hole drilled in a body of a pump device or the like.

[Conventional technology]

Conventionally, for example, in a pump casing, etc., the main body is made of Aj2 alloy, and after drilling various passages in the body, when it is necessary to close the opening on the end face of the hole, a steel ball is usually inserted into the opening. [Problem to be Solved by the Invention] The conventional plug assembly M for plugging the body opening has the above-mentioned structure, and due to the difference in thermal expansion coefficients between the body body and the ball, Occasionally, sealing failures occur, and in extreme cases, the ball may fall out of the opening. Therefore, in order to prevent such defects, it is possible to increase the press-fitting allowance for the steel balls, but in that case, the tightening allowance will further increase at low temperatures, and in reality, the body main body made of Al alloy This increased stress and resulted in damage, resulting in a significant lack of reliability. Therefore, in order to avoid such inconveniences, a filling member is screwed together with a sealing material into the opening, but this inevitably increases the number of man-hours and processing costs.

Therefore, an object of the present invention is to provide a plug device having a simple structure and having a sufficient sealing function for the opening of a body made of an An alloy despite thermal changes.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, the ball is made of a material having almost the same coefficient of thermal expansion as the body made of an Al alloy, and the opening filling member is A certain ball is being hardened.

(Function) According to the present invention, the hardened ball does not get used to being scraped when press-fitted into the opening of the main body, and its sealing function is not impaired by thermal changes.

(Example) The present invention will be explained below with reference to an illustrated example.
FIG. 3A is a cross-sectional view of the plug device of the present invention in which the plugging ball shown in FIG. 3B is fitted into the body opening.

In the figure, (1) is a body of a pump etc. made of AIt alloy, (2) is a hole drilled in this body (1), and (3)
is a ball made of the same <AA gold alloy as the body (1) above, whose surface layer is anodized, and is driven into the end opening (2a) of the hole (2) to fill the hole (2). ing.

In this way, the ball (3) has the same AI as the body (1).
l.Since it is made of an alloy, the coefficient of thermal expansion is the same, and there is no problem with conventional sealing performance due to temperature changes.Moreover, the ball (3) is hardened by alumite treatment on its surface. Therefore, there is no need to worry about the ball (3) being scraped and not being able to fit tightly when driving into the body (1), and it is possible to obtain good workability equivalent to that of conventional steel balls.

Next, FIG. 2 shows another embodiment of the present invention.

In this embodiment, the ball (4) has a cylindrical protrusion (
It is unique in that 4a) is provided. This protrusion (4a) is formed by cold forging during ball processing, and the protrusion (4a) is formed during alumite treatment of the ball (4).
a) is sandwiched between electrodes so that an anodic oxide film is applied to the entire circumference of the spherical part.

In this way, in the case of the first embodiment, it is possible to prevent the possibility that a missing portion of the treated film will occur at the electrode contact portion when performing the alumite treatment. In other words,
In the case of the first embodiment, care must be taken to prevent the electrode contact part of the ball (3) from coming into contact with the press-fit seal part at the opening (2a) of the hole (2), but in the case of the second embodiment, In this case, such considerations are not required at all, and the curing process can be easily and reliably performed by sandwiching the protrusion (4a).

(Effects of the Invention) As described above, according to the present invention, the ball made of a material having almost the same coefficient of thermal expansion as the body made of an Al alloy is subjected to surface hardening treatment. The ball does not get scraped when the ball is press-fitted into the hole of the body, and the sealing function is not impaired even by thermal changes.

[Brief explanation of the drawing]

The figures all show embodiments of the plug device according to the present invention, and FIG. 1(a) is a cross-sectional view of the plug device showing the plugging ball fitted into the body opening. (
b) is a side view showing only the ball, Fig. 2(a), (
b) shows other embodiments of the present invention in FIGS. 1(a) and (b)
This is a similar diagram. (1): Body (2): Hole (2a): Opening (3), (
4): Ball (4a): Projection Patent Applicant Jidosha Kiki Co., Ltd. Representative Patent Attorney Sou Yamazaki J ) 1: Niu self 4a two-piece rod

Claims (1)

[Claims] It comprises a body made of an Al alloy with holes machined, and a ball made of a material having a coefficient of thermal expansion almost the same as that of the body and filled in the hole, and the ball is hardened on its surface. Features a plug device.