JPH06330805A - Fastening structure of cylinder - Google Patents

Abstract

PURPOSE:To prevent deformation of a sleeve by bolt fastening and prevent seizure of a piston and piston hammering noise. CONSTITUTION:In the cylinder of an engine in which a sleeve 4 is fitted in a cylinder barrel 5 and which is fastened by bolts, a spacer of nearly the same length as the axial length of a hole part is fitted to the inner circumference of a bolt inserting fastening hole part 6 to be formed in the cylinder barrel 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine cylinder fastening structure.

[0002]

2. Description of the Related Art Generally, an engine cylinder has a flanged sleeve 2 fitted to an aluminum cylinder barrel 1 as shown in a plane view of FIG. 5 and a sectional view taken along line CC of FIG. The flange 2a of the sleeve 2 and a cylinder head (not shown) are fastened to the cylinder barrel 1 with bolts that pass through the bolt insertion holes 3 of the cylinder barrel 1.

[0003]

However, in the above fastening structure, the roundness of the sleeve 2 is deformed by the bending action of the fastening force F in the directions indicated by the arrows a and a in FIG. 2, and the sleeve 2 expands in the bolt insertion direction. Deformation b occurs. This deformation b is further amplified during actual operation and causes seizure of the piston.
If the clearance between the piston and the sleeve 2 is increased, it will cause a piston striking sound.

On the other hand, in the case of a sleeve having no collar, the Young's modulus of the cylinder barrel 1 made of aluminum and the sleeve made of iron are largely different, and the Young's modulus of the cylinder barrel 1 is smaller than that of the sleeve, so that the sleeve is deformed by tightening. Of the cylinder barrel 1 made of aluminum, and thus the sleeve undergoes the same bulging deformation as described above.

In view of this, the present invention prevents the sleeve from bulging and deforming due to the tightening of bolts when it has a collar sleeve, and in the case of a collarless sleeve, the sleeve due to the difference in Young's modulus between the cylinder barrel and the sleeve. An object of the present invention is to provide a cylinder fastening structure that prevents deformation, does not cause piston seizure, and does not generate piston striking sound.

[0006]

As a means for solving the problems of the above-mentioned prior art, the present invention is a cylinder of an engine in which a sleeve is fitted to a cylinder barrel and fastened by bolts. In the case of a sleeve having no flange, a spacer having a length substantially equal to the axial length of the hole is fitted to the inner circumference of the bolt insertion tightening hole formed in the sleeve. A bolt hole for tightening a bolt is formed in a flange portion having a length corresponding to the axial length of the cylinder barrel on the outer periphery of the.

[0007]

When the spacer is fitted in the tightening hole of the cylinder barrel, the tightening force is restricted by the spacer when tightened by the bolt, so that the tightening force does not affect the sleeve and the sleeve expands. Deformation does not occur. Further, in the case where the flange portion of the sleeve is projected in the axial length corresponding to the axial length of the cylinder barrel and the tightening hole is formed in this, the tightening force by the bolt is completed only by the sleeve, so that the cylinder barrel It is not affected and the sleeve does not deform.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the drawings.

FIG. 1 shows a case of a sleeve 4 without a collar. A cylindrical spacer 7 is press-fitted into a bolt insertion tightening hole portion 6 of a cylinder barrel 5. As shown in FIG. 2, the axial length of the spacer 7 is the same as the tightening hole 6
The tolerance of the cylinder barrel 5 is slightly "-" smaller than the axial length thereof, and the deformation of the cylinder barrel 5 when tightened by bolts is restricted by the length of the spacer 7.

FIG. 3 shows the case of the sleeve 8 with a collar, and the collar portion 9 of the sleeve 8 covers the position where the above-mentioned tightening hole portion 6 of the cylinder barrel 5 is provided as shown in FIG. Is provided on the outer peripheral surface of the sleeve 8 with the collar portion 9
A bolt insertion tightening hole portion 10 is formed in the. The length of the collar portion 9 in the axial direction reaches the base surface 5a of the cylinder barrel 5. Therefore, the tightening force of the bolt passing through the tightening hole 10 is restricted only by the sleeve 8 and is not affected by the cylinder barrel 5.

In the case where the spacer 7 is fitted in the tightening hole portion 6 of the cylinder barrel 5 as shown in FIGS. 1 and 2, the tightening force is restricted by the spacer 7 when tightened by the bolt, and the tightening is performed. The force does not affect the sleeve 4, so that the sleeve 4 does not undergo bulging deformation.

Further, as shown in FIGS. 3 and 4, when the flange portion 9 of the sleeve 8 is projected to a length corresponding to the axial length of the cylinder barrel 5 and the tightening hole portion 10 is formed in this, the bolt 9 is tightened. The force is applied only to the sleeve 8 and is not affected by the cylinder barrel 5, so that the sleeve 8 is not bulged and deformed.

[0013]

As described above, according to the present invention, since the sleeve does not bulge and deform due to the fastening of the cylinder, seizure and galling of the piston do not occur.
It is possible to improve the durability and simultaneously prevent the generation of a piston hitting sound.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view showing another embodiment of the present invention.

FIG. 4 is a sectional view taken along line BB of FIG.

FIG. 5 is a plan view showing a conventional technique.

6 is a sectional view taken along line cc of FIG.

[Explanation of symbols]

 1,5 Cylinder barrel 2,4,8 Sleeve 3,6,10 Tightening hole 7 Spacer

Claims (2)

[Claims] 1. In a cylinder of an engine in which a sleeve is fitted in a cylinder barrel and fastened by bolts, a bolt insertion tightening hole formed in the cylinder barrel has an inner circumference substantially equal to an axial length of the hole. A cylinder fastening structure in which a long spacer is fitted. 2. In a cylinder of an engine in which a sleeve is fitted in a cylinder barrel and fastened by bolts, a bolt for inserting a bolt into a flange portion having a length corresponding to the axial length of the cylinder barrel on the outer circumference of the sleeve. A fastening structure for a cylinder characterized in that a hole is formed.