JPH01193003A - Manufacture for side housing in rotary piston engine - Google Patents

Abstract

PURPOSE:To enhance the yield of a raw material and a product, and durability, by applying step down work on a seal sliding surface of a side housing raw material after carrying out shot peening on said sliding surface, and forming a flame coating layer superior in its abrasion resistance thereon. CONSTITUTION:On the occasion of manufacture of a side housing, after the side housing raw material 1 made of aluminium alloy is firstly cast, a rough work is carried out in order to obtain smoothness on the surface. Next shot peening is carried out under comparatively soft condition by using a shot of a small diameter throughout the surface of a seal sliding surface 11 side on the side housing surface, so that sealing process of a blow hole existent in the raw material 1 is carried out. And, finish work of the raw material is carried out, and further, a convex part 1A is formed by applying down work on the part requiring abrasion resistance of the side housing surface. And after that, a ceramics flame coated layer 2 is formed on this convex part 1A, so that grinding work is carried out in order to give this flame coated layer 2 a prescribed surface roughness. Then, a product is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a side housing for a rotary piston engine.

[Prior Art and its Problems] Conventionally, rotary piston engines have been known in which a housing is made of an aluminum alloy in order to reduce weight. However, since aluminum alloy is relatively soft and has poor wear resistance, when it is applied to the side housing, it is difficult to use the side housing where the side seals, oil seals, and other sealing members attached to the rotor come into contact and slide. There is a problem in that the seal sliding surface of the housing is significantly worn.

Therefore, a sprayed layer of a material with good wear resistance, such as ceramics, is provided on the seal sliding surface to improve the wear resistance.

Incidentally, as the material for such an aluminum alloy side housing, sand casting is currently used. For this reason, there is a problem in that the yield of the material and, by extension, the yield of the product is low due to the occurrence of blowholes during casting of the material. $
Shot peening (Japanese Unexamined Patent Publication No. 61-26527
It is well known that shot peening is used to seal blowholes in the side housing material to improve yield.

However, the seal sliding surface of the side housing is subjected to normal shot peening conditions 1, for example, a pressure of 5 kg/c 2,
When performing side hole treatment with steel ball P1600g.

Although a sufficient cutting hole effect can be obtained, the peening surface becomes extremely rough, and there is a drawback that post-cutting is troublesome on surfaces that require high precision. or.

Due to shot peening, residual compressive stress is generated on the surface, and the material gradually changes into a convex shape due to the influence of this compressive stress, so the central layer N of the sprayed layer formed after shot peening becomes thinner. There is.

[Object of the Invention] In view of the above-mentioned circumstances, the present invention provides a rotary piston engine which can perform side hole treatment in a short time by shot peening, and also reduces convex deformation of the material and improves the material and product yield. The purpose is to provide a method for manufacturing a side housing.

[Structure of the Invention] Therefore, in the method for manufacturing a side housing for a rotary piston engine according to the present invention, shot peening is applied to the seal sliding portion of a cast side housing material, and then the seal sliding portion is stepped down. The seal is machined to be more concave than its surroundings, and a thermal sprayed layer that provides excellent wear resistance is formed on the sliding part of the seal.

According to the above manufacturing method, the blowhole can be sealed by shot peening, and the layer with residual compressive stress on the surface can be removed by lowering the shot peened portion after shot peening. Therefore, convex deformation caused by the concave deformation due to the influence of the underlying layer with residual tensile stress can be suppressed, and a sufficient thickness of the sprayed layer can be ensured. Therefore, the yield of the side housing material and ultimately the product can be improved.

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

FIG. 1 shows a manufacturing procedure showing a further embodiment of the side housing manufacturing method of the present invention, and FIG. 1s2 shows a side housing to which this manufacturing method is applied.

To explain the manufacturing method, first, aluminum alloy (AC
Ordinary #6J that puts the molten metal of 4A) into the sand mold? [Forming the aluminum alloy side housing material l by the method (Figure (A))] Next, after demolding the sand mold, the side housing material l is subjected to a predetermined heat treatment (for example, T -8 treatment, etc.), and then, to obtain smoothness of the inner surface of the side housing, roughness-1 treatment, etc. is applied (
(B)), after sealing, the entire surface of the rough-processed material l on the seal sliding part ll side is shot under a softer condition than before (shot diameter = 150
Shot peening is performed at a blast pressure of 35 kg/cm2 or less) to treat the side holes of the blowholes present in the material 1 (Figure (C)).

After this shot peening, the material 1 is immediately subjected to finishing processing, and furthermore, the part of the side housing surface that requires wear resistance, that is, the seal sliding part 1.1 (on which the seal member attached to the rotor slides) The area corresponding to the meshed area in Fig. 2) is subjected to thermal spraying undercoating with step-cutting and [. ((E) 124).

Then, the part corresponding to the seal sliding part 11 from the concave part IA was degreased by cleaning with perchloromethane, and the surface was treated with Simitplast.

A thermally sprayed layer 2 of a material 1 having excellent wear resistance, such as ceramics, is formed, and this thermally sprayed layer fi2 is subjected to a grinding process to obtain a predetermined surface roughness (FIG. (F)).

Thereafter, a tension bolt insertion hole 13, a positioning bolt insertion hole 14, etc. are formed in the joint portion 12 of the side housing with the rotor housing using a drill or the like.
Obtain the completed id housing shown. In addition, 71
In Figure S2, 15 is the insertion hole into which the rotor eccentric shaft is inserted;
Reference numeral 6 indicates a water jacket formed at the joint 12 for circulating cooling water.

Like this! Example 1 of two side housings
．． Table 1 shows the test data for Comparative Examples 1 to 2 and Comparative Examples 1 to 3.

Table 1 As is clear from these results, Example 1.2, in which shot peening was performed under softer conditions than before and then step-edge processing was performed, showed that the amount of deformation before thermal spraying and the number of cavities on the sprayed surface were Both meet the target values (standards).

On the other hand, in Comparative Example 1, in which step-down addition T was performed after peening (shimy) under the same conditions as before, the number of cavities was cleared, but because the shot peening conditions were harsh, The deformation of the seal sliding surface (seal sliding portion 11) becomes extremely large.

In addition, in Comparative Example 2, in which the step peening process was not performed under the same shot peening conditions as in the Example, the residual compressive stress was
Because the soda remains, the deformation of the seal sliding surface before thermal spraying becomes large even though the shot peening conditions are soft.

Furthermore, in Comparative Example 3 in which shot peening was not performed, the amount of deformation of the seal sliding surface was small.

Since there is no shot peening process, the holes are not sealed and there are many cavities.

In this way, in this example, the blowhole was sealed by shot peening under softer conditions than in the past, so the number of cavities was extremely small, and since step-down processing was performed afterwards, the seal m movement was reduced. It was possible to reduce the amount of convex deformation of the surface and to ensure a sufficient layer thickness in the central part of the sprayed layer, which is the sliding part of the oil seal where particularly wear resistance is required. Therefore, the yield of nide housing materials and products can be improved.

[9. Bright Effects] According to the method for manufacturing a side housing of a rotary piston engine according to the present invention as described in 1.

After shot peening, the seal sliding part is stepped down to form a sprayed layer, so sealing can be done in a short time and deformation of the material due to residual compressive stress can be reduced, reducing the thickness of the sprayed layer. Sufficient thickness can be ensured. Therefore,
The yield of side housing materials and products can be greatly improved, and a highly durable side housing can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the procedure of an embodiment of the side housing manufacturing method according to the present invention, and FIG. 2 is a front view of a side housing to which the same embodiment is applied. 1... Side housing material 2...・Thermal spray layer 11...Seal sliding part ￥1 Figure 2

Claims (1)

[Claims] When manufacturing an aluminum alloy side housing for a rotary piston engine, shot peening is applied to the seal sliding part of the cast side housing material, and then the seal sliding part is processed to be lower than its surroundings, A method for manufacturing a side housing for a rotary piston engine, characterized in that a thermal spray layer with excellent wear resistance is formed on the sliding part of the stepped-down seal.