US2575938A - Tool for expanding cylinder liners - Google Patents

Description

Nov. 20, 1951 A. M. BRENNEKE TOOL. FOR EXPANDING CYLINDER LINERS Filed Nov. 22, 1949 /Y QZ 5 Q1 @j d) Q0 QZ Q J2 J ZZ IN V EN TOR.

QfM/Yrenne@ Patented Nov. 20, v1951 TOOL` FOR EXPANDING CYLINDER LINERS Arthur M. Brenneke, New Castle, Ind., assignor to Perfect Circle Corporation, Hagerstown, Ind., a corporation of Indiana Application November 22, 1949, Serial No. 128,827

` 4 Claims.

The invention relates to a tool for assembling sleeves or liners in cylinders, such as the cylinders of internal combustion engines, compressor or the like. v Y

In order to avoid the necessity of reboring worn engine cylinders and of replacing the original pistons and piston rings with oversized pistons and rings to nt the rebored cylinders, engines have been built with cylinder liners in the form of thin sleeves which can be withdrawn when Worn and replaced with new ones having stand ard hores. The use of liners in cylinder blocks also permits use of cylinder block castings which could not be usedwithout liners because of imperfections inthe cylinder bore surfaces, since a liner covers over such imperfections and provides a `proper surface throughout the cylinder bore.

However, if a liner is to be employed, it must be in tight contact with the cylinder casting at all times and under all conditions of operation. Thus, it must maintain such contact in order to provide proper heat conductivity. Such contact is also necessary to prevent any seepage of oil between the liner and the cylinder block, since the oil would carbonize and cause distortion of the liner when the engine cools on stopping. Such distortion would be cumulative by repeated operation and stopping of the engine and would become so great that it could not be tolerated.

The general object of the invention is, therefore, to provide a novel tool for expanding a liner into a cylinder block, which effects the necessary degree of intimate contact between the liner and the block.

Another important object is to provide a tool ofthe foregoing character, by which a large expanding force may be exerted against the liner with a minimum of effort required to operate the tool.

A further object is to provide a novel tool of the foregoing character, which may be both rotated in and moved longitudinally of the bore either separately or simultaneously, and which is provided with rolling expanding elements involving a minimum of friction in spite of the large expanding force exerted thereby.

Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawings, in which:

Figure 1 is a side elevational view, partly in section., of a tool embodying the features of the invention' and showing such tool in `operative position relative to a cylinder liner.

(Cl. S-80.5)

-2 Fig. 2 is a sectional view taken on the line 2--2 of Fig. l. Fig. 3 is a fragmentary sectional'vieW-similar to the lower end of Fig. l, but showing a modified form of the tool.

Fig. 4 is a transverse sectional view taken on the line 4 4 of Fig. 3.

A tool embodying the features of theinvention is adapted to be inserted within the liner and utilizes fluid pressure to force expanding elements radially outward into expanding en-` gagement with the liner. The pressure fluidi-is applied directly to the expanding elements and thus minimizes the friction involved in operating the tool. The expanding elements are preferably in the form of rolling balls `which provide a relatively small area of contact with the liner' and have a relatively large area exposed to the pres? sure fluid so that a large expanding force is ap plied to a relativelysmall area of the liner, Thusy the expanding force is suilicient to expand a liner of the character herein contemplated with only a moderate pressure in the pressure fluid. The expanding elements or balls are carried at the end of an elongated shaft by whichthey maybe readily inserted into the liner and, because of their spherical character, they may both be rotated and moved longitudinally of the liner with-` out undue friction. The pressure fluid may be either air or oil, and if `the latter is utilized, lubrication of the balls is thereby inherently provided for. With a tool of this character, a minimum of effortV is required to operate the tool in` effecting expansion of a liner. y

As shown in the drawings, the illustrated ern-f bodiment of the invention comprises a tubular shaft le, which is journaled in a sleeve II adjacent one end, and at its other end carries a head l2 in which are mounted the rolling expanding elements comprising balls I3. Pressure duid is" adapted to be supplied to the interior of the shaft I0 and in the head l2 is a plurality of radial pasI sages Il! in which the balls I3 are positioned.-

The radial passages I4 are in communicationl with the interior of the shaft I0 and, whilethe' head provides a closure for such interior endwise 2, the shaft I0, adjacent its lower end, is provided with a collar` l5 rigidly secured to the shaft, as by welding, and below the collar I5 the shaftv is In the particular form illustrated in Figs. land threaded, as at I6. The head I2, which is generally cylindrical in form, is provided with a hub portion I1 in threaded engagement with the threads I6 and abutting the collar I5 to prevent leakage of fluid along the threads. Beyond the end of the shaft I 0, the head I2 is provided with a central cavity 20 from which the radial passages I4 extend. In the present instance, three passages I4 are shown with a ball I3 in each. Thus, when pressure fluid is supplied through the shaft I0, the pressure of the fluid will be applied directly to the balls to force the balls I3 outwardly of the radial passages I4 and into contact with the interior surface of a sleeve or liner 2I, which is here shown as being mounted within a cylinder bore of a cylinder block 22. The pressure of the pressure fluid acting directly on the balls I3 forces them outwardly into expanding engagement with the liner 2|, thus eliminating the friction occurring if mechanical expanding means were employed. In order to prevent the balls from falling out of the head I2 when the tool is removed from the liner, means may be provided at the ends of the passages I4 to prevent, the balls from being moved completely out of the passages I4, which means is here illustrated as a garter spring 23 tting in an annular groove in the head I2. The supply of pressure fluid to the shaft I0, of course, is stopped before the tool is removed from the liner to prevent the balls from being forced out againstJ the retaining pressure of the garter spring 23.

The sleeve I I acts as a support for the shaft I and has a means through which pressure fluid is supplied to the interior of the shaft. To function as a support, the sleeve I I is mounted between two collars 24, rigidly secured to the shaft as by setscrews 25, the collars 24 being in abutment with the ends of the sleeve II. The sleeve is provided with a radially positioned threaded hole 26 into which an anchor barmay be inserted to hold the sleeve against rotation.

' To supply pressure uid to the interior of the shaft, the sleeve II, midway between its ends, is

provided with a radially positioned threaded aper-V vture 21, into which a pipe fitting 30 may be fixed for connection to a hose leading to a source of pressure fluid. On the interior of the sleeve, the aperture 21 opens into an annular groove 3| registering with an annular groove 32 formed on the exterior of the shaft I. Leading from the annular groove 32 to the interior of the shaft IIIv is a supply passage 33. Thus, as the shaft rotates within the sleeve II, pressure uid may be intro-- duced `into the interior of the shaft by the pipe fitting 30. the aperture 21, the annular grooves 3|- and 32, and the supply passage 33. On opposite sides of the pressure iiuid supply means, a pair of seals, vindicated generally at 34, are mounted in the sleeve adjacent the collars 24 to prevent leakage along the shaft. The sleeve may also be provided with annular lubricant-receiving grooves having fittings 35 for introducing the lubricant, the lubricant grooves, of course, being positioned at opposite sides of the annular grooves 3I and 32.

The shaft III projects beyond the upper colla 24 and is provided, at its outer end with a sealing plug 36 to prevent escape of pressure fluid in that direction., It also maybe provided with a cross pin 31, by means of which the shaft may be rotated. I

In operation, the head of the tool is inserted into the liner 2I when the latter has been positioned within the cylinder block 22. Pressure 4 uid is then supplied to the interior of the shaft I0 through the fitting 30, and the balls I3 are forced outwardly in the passages I4 into expanding contact with the interior surface of the liner 2|. It will be noted from inspection of Figs. 1 and 2 that the pressure fluid is applied to the full diameter of the balls While the balls contact the liner only over a very limited area. Thus, the total force of the pressure fluid on the balls, when translated to the small area of engagement of the balls with the liner, results in a very high expanding force acting on the liner. The tool may be rotated within the liner, while pressure is applied to the balls, to expand the liner throughout an annular path. If longitudinal movement is imparted to the tool at the same time as rotary movement, then the path of expansion will be a spiral, or, of course, if merely longitudinal movement of the tool is employed, a straight line of expansion results. However, in any case, the only friction occurring is that'bel tween the ball and the liner itself and between the balls I3 and the interior surfaces of their passages. Thus, far less friction is involved in the operation of thev device than in the vcase' where expanding elements are mechanically expanded. If oil is the pressure uid that is used, then the slight clearance between the balls and their passages permits a lm of oil to be carried on the ball surfaces, lubricating the point of contact of the balls with the passage surfaces aswell as the point of contact of the balls with the liner.

It is, of course, contemplated that the tool will be reciprocated or rotated in'any ofthe foregoing, manners so that the liner 2I may be expanded In actual practhroughout any area desired. tice, it has been found that with three balls o f 11A," diameter and utilizing oil at 150 poundssures are exerted on all the balls at allV times.V This feature results from the fact that the balls are independently movable, but, since they are all subjected to the same pressure, the tool --may shift relatively to the balls to centeritself within the bore. 1 v.

In Figs. 3 and 4, I have shown fragmentarilyY a modified form of tool in which six ballsr 4|)V are employed, there, of course, being six radial passages 4I extending from the central cavity 20 in the head I2, in which the balls 40 arelocated. While, in this instance, a smaller total force is applied to each ball for a given fluid pressure, because'of the smaller diameter of the balls, the sharper curvature of the balls reduces the area of contact thereof with'the liner. In the modied form shown in these two figures, the means for retaining the balls within their passages 4I comprises reducing the diameter of the bores 4I at their outer ends to a slight extent by peening over the margin of the passages, as indicated at'42, the amount of peening being only suicient to provide a diameter at the outer ends of the passages 4I which is slightly less than the diameter of the balls G0. In this form of tool, however, the means for supplying pressure nuid to the interior of the shaft IIl may be the same as that shown in Fig. 1. 'l

I claim:

1. A tool for expanding a liner within a cylindrical bore, comprising a rotatable tubular shaft having a head adapted to be inserted in the bore of the liner, said head having a plurality of radial passages communicating with the interior of the shaft, said shaft being connectible with a source of pressure fluid, and a plurality of balls mounted in the respective passages, said pressure fluid being adapted to be introduced by said tubular shaft into direct engagement with said balls, whereby said balls are forced outwardly by the pressure fluid into engagement with the liner.

2. A tool for expanding a, liner within a cylindrical bore, comprising a rotatable tubular shaft adapted to be connected to a source of pressure fluid, a head mounted on one end of the shaft and having a plurality of radial cylindrical passages having their inner ends communicating with the interior of the shaft, and a plurality of balls mounted in the respective passages, said pressure fluid being adapted to be introduced by said tubular shaft into direct engagement with said balls, whereby said balls are forced outwardly by the pressure fluid, each ball having a diameter substantially closing its associated passage to prevent material loss of pressure fluid about the ball but with sulcient clearance to permit the ball to roll when in contact with the liner.

3. A tool for expanding a liner within a cylindrical bore, comprising a head adapted to be inserted into the bore of the liner and having a plurality of radial passages interconnected at their inner ends, a plurality of balls mounted in the respective passages, and means for supporting said head and for supplying pressure fluid to the inner ends of said passages, to apply the pressure uid directly to said balls whereby said balls are forced outwardly by the pressure fluid into engagement with the liner.

4. A tool for expanding a liner within a cylindrical bore, comprising a head adapted to be inserted into the bore of the liner and having a plurality of radial passages extending inwardly from the periphery of the head and interconnected at the inner ends, a plurality of balls mounted in the respective passages, said head having an axially extending bore extending from the inner ends of said passages to one end of said head and a rotatable tubular shaft having one end secured in said last-mentioned bore and adapted to be connected to a source of pressure fluid, said shaft being adapted to supply the pressure uid to the inner ends of said passage to apply it directly to said balls whereby said balls are forced outwardly by pressure uid into engagement with the liner.

ARTHUR M. BRENNEKE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 600,681 Sharp Mar. 15, 1898 1,794,797 Rockwell Mar. 3, 1931 2,361,434 Switees Oct. 31, 1944 2,459,643 Hartley Jan. 18, 1949 2,465,677 Deverall Mar. 29, 1949 2,480,858 Hobbs Sept. 6, 1949 FOREIGN PATENTS Number Country Date 15,579 Great Britain Oct. 4, 1889 489,084 Great Britain July 19, 1938 400,780 France June 24, 1909 301,116 Germany Oct. 9, 1917 345,556 Germany Dec. 13, 1921

Images