CS255912B1 - Cylinder for internal combustion engine - Google Patents

Abstract

The invention relates to the field of automotive engineering and addresses the problem of a non-separable connection of a cylinder consisting of two parts made of component metals with different thermal expansion. A cylinder for internal combustion engines consists of two parts made of component metals with different thermal expansion, which are connected to each other and provided with a heat transfer medium on the contact surfaces. The essence of the invention lies in the fact that the contact surfaces of both parts of the cylinder are provided with conical threads and at least two gaps are formed between the contact surfaces along the entire length of the thread pitch, symmetrically to the vertical axis of the cylinder.

Description

The invention relates to cylinders for internal combustion engines which consist of two parts.

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The cylinders for internal combustion engines consist of an outer and an inner part, usually of component metals with different thermal expansion. The outer part is fitted with an overlap on the inner part. The contact surfaces of both parts are provided with a heat transfer medium to improve the transfer from the inner to the outer part. Both parts are joined by pressing. The contact surfaces of both parts are cylindrical and must be machined to exact tolerances before joining, which requires increased production technology requirements. During the operation of the engine, due to thermal dilatations, the joint becomes loose and thus the heat transfer is impaired, which causes an increase in the cylinder heating. The connection cannot be restored.

It is an object of the invention to provide a strong, non-demountable connection in order to improve heat transfer.

The cylinder for internal combustion engines consists of two parts, component metals with different thermal expansion, which are interconnected and provided with heat transfer medium on the contact surfaces. SUMMARY OF THE INVENTION The invention is characterized in that the contact surfaces of the cylinder part are provided with conical threads and at least two gaps are formed symmetrically between the contact surface along the entire pitch of the thread.

The roll according to the invention achieves a firm, non-detachable connection of the two parts, which ensures a constant contact between the two parts. areas, thus improving heat transfer. Kenya requires precise machining of the interface, simplifying production technology. If the joint is loosened, it can be restored by tightening.

An example of a roll according to the invention is shown in the attached drawing, wherein Fig. 1 shows the roll in longitudinal section and Fig. 2 in a top view. ... ·. ' .

The roll 1 consists of an outer part 6 and an inner part 2 of component metals with different thermal expansion. The outer part 2 is of aluminum alloy and the inner part 2 ^of cast iron. The contact surfaces of the two parts 2,2 are provided with conical threads 60, 62. Between the contact surfaces, along the entire length of the thread pitch 6, at least two gaps 6 are formed symmetrical to the vertical axis of the roll 1, by flattening the contact surface of the inner part 2 of the roll 1.

. The connection of the two parts 2 »2 ^is done by hot screwing. The gaps 6 serve to reduce the stresses on the inner circumference of the outer portion 2 of the cylinder 1, while the engine is operating, and to ensure that the formed joint is not detachable. · '

The cylinder 1 thus formed can be used for both water and air-cooled engines.

Claims (1)

SUBJECT MATTER A L E Z U Cylinder for internal combustion engines consisting of two parts, of component metals of different thermal expansion, connected to each other, characterized in that the contact surfaces of the two parts (2), (3) are provided with tapered threads (4), (5) and between at least two gaps (6) are formed symmetrically with respect to the vertical axis of the cylinder (1). 1 drawing,