US3603183A

US3603183A - Shaft-truing devices

Info

Publication number: US3603183A
Application number: US863250A
Authority: US
Inventors: Denver L Walker
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-10-02
Filing date: 1969-10-02
Publication date: 1971-09-07
Anticipated expiration: 1988-09-07

Abstract

A manually operated, crankpin truing device, adapted to be mounted on a crankpin without removal of the crankshaft from the engine. Machining of the high surfaces on the crankpin is effected by cutters which are urged, by spring action, to contact such surfaces, but are prevented from making contact with the low surfaces by the cam action between the elliptical pin and the shaft-contacting rollers provided for that purpose.

Description

O United States Patent 1111 @www [72] Inventor Denver L. Walker [56] References Cited 754 Glenside Drive, Lafayette, Calif. 94549 UNITED STATES PATENTS [21] A PPL NO- 8633509 9 1,284,106 11/1918 Holton 82/4 B [221 Filed 0*- 27, 119671 1,370,141 3/1921 McNicholas i. 82/4 B [45] Patented Sept f 1,652,868 12/1927 Maloney 82/4 B 2,219,245 10/ 1940 Zitzerman 82/4 E Primary Examiner-Leonidas Vlachos Attorney-John Walker ABSTRACT: A manually operated, crankpin truing device, [54] SHAFT'TING, DEFYICES adapted to be mounted on a crankpin without removal of the 7 clalms rawmg lgs crankshaft from the engine. Machining of the high surfaces on [52] U.S. Cl.....- 82/4 B, the crankpin is effected by cutters which are urged, by spring 51/73 action, to contact such surfaces, but are prevented from mak- [5 l] Int. Cl B23b 5/18 ing contact with the low surfaces by the cam action between [50] Field of Search 82/4 B; the elliptical pin and the shaftcontacting rollers provided for that purpose.

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ABY m/ Age/2f SHAFT-TRUING DEVICES This invention relates to crankpin truing devices, and more particularly to a type of tool which can be used on a crankshaft without its removal from an engine. It has been long established, that after continued operation the normal wear to which the crankpins of the crankshaft of an engine are subjected, results in an uneven erosion of material which leaves the crankpins in an out-of-round, or slightly elliptical condition. lf this condition is not corrected, continued operation of the engine will result in damage to the parts affected.

It is the principal object of the present invention to provide a crankpin truing device which can be applied directly to the crankpin upon the removal of the connecting rod therefrom.

Another objective of the invention is the provision of a device which is automatically adapted to the removal of material from the high surfaces only of an out-of-round shaft.

A further object of the invention is the provision of a device which can be adjusted to resurface a crankpin or shaft to a predetermined diameter. I

A still further object of the invention is the provision of a device which is simple to manufacture, of compact form and easy to operate. These and other objects of the invention will become apparent during the course of the following description, taken in connection with the accompanying drawing forming a part hereof, and in which:

FIG. I is an elevation of a preferred embodiment of my device.

FIG. 2 is a transverse cross section taken on line 2-2 of FIG. l. FIG. 3 is a fragmentary section taken of line 3 3 of FIG. 1.

FIG. 4 is a diagram showing elements ofthe device in a particular angular relationship with reference to an out-of-round shaft.

FIG. 5 is a diagram similar to that of FIG. 4, with the device rotated through an angleof 90.

Referring to the drawing in detail, the body of my device comprises an annular member which has been dimidiated to form tow identical portions l0, each portion being somewhat less than a complete semicircle. The material removed in the parting of the solid ring leaves a space Il between the halves when they are arranged in their original concentric relationship. The width of the space l1 will be determined by the range of crankpin diameters which a particular tool will be required to handle.

Adjustable bolts 12 are provided to secure the halves 10 in their operating relationship, each bolt passing through a counterbored aperture 13, in one of the sections, and being engaged by a threaded hole 14 in the other section. Compression springs 15, contained in each of the counterbores of the apertures 13, encircle the bolts, and, being placed between the heads of said bolts and the shoulders formed by the bottom of the counterbores, act to resiliently urge the sections l toward one another. The force exerted by the springs is readily adjustable by the advancing or retraction of the bolts 12 as desired. The limit to the closing of the halves 10 is governed by the selected thickness of annular spacers I6, one of which encircles each of the bolts, and is located intermediate the confronting faces 17 at the ends of the halves.

The assembled bolts l2, springs I and spacers 16 are symmetrically arranged in parallel relationship with a median line passing through the halves of the body of the tool, said line being nonnal to the dividing space between the two portions. This line will be referred to thereinaer as the vertical centerline.

FIG. 3 illustrates a detail of a preferred embodiment of a roller assembly 18 which comprises a double-ended shoulder pin I9, having an antifriction bearing 20 mounted on each end thereof. Each body portion 10 is provided with a roller assembly 18. As can be seen by reference to FIG. l, the assemblies are diametrically opposed, are radially equidistant and. have their common centerline oriented at 45 to the vertical centerline of the device. A double-counterbored aperture 2l,

located as described above, is provided in each of the portions ll0 for the reception of the shoulder pins I9, as indicated, the pins being driven tightly therein. The counterbore on each side of the portions l0 provides a recessed mounting for the bearings 20.

The spacing of the pins 19, and the diameters of the rollers or bearings 20 is such that the said rollers project into the circular space 22 bounded by the body portions 10 when in their assembled position.

Also extending into the space 22 is a pair of cutters 23. These cutters have their cutting edges, or surfaces, as the case may be, in a diametrically opposed relationship similar to that of the roller assemblies 18, their respective center lines being normal to one another. The cutters, which extend the length of the tool, are tightly inserted in slots 24 in the body portions 10 of the device. The radial location of the cutting edges, as required by the diameter of a particular crankpin being operated upon, can be adjusted by the use of shims 25 of appropriate thickness, as illustrated.

Apertures 2 have been provided in the outer edge of the device, into which any suitable implement, such as a rod or bar, may be inserted to effect rotation. In order to use the device, a crankshaft is rotated to a position where the pin which is to be machined is accessible, and after removal of the connecting rod, the tool is simply mounted in its place, and is then rotated until the operation is complete. Referring to FIGS. 4 and S, it will be noted that the roller assemblies I8 and the cutters 23 are all tangent to a common circle 27 which is equal in diameter to the major axis of a slightly elliptical crankpin P, and for a particular operation, the shims 16 will be of such thickness as to allow all four points of contact to approach a position where they would coincide with the circumference of a circle equal in diameter to the minor axis of the pin. It will be obvious from the fact that as all four points of contact are fixed with reference to their location in the identically and symmetrically arranged halves of the device, any variation of the space 11 will not materially affect this relationship. When the cutters are in contact with the larger surfaces of the pin, as shown on FIG. 4, the springs are free to facilitate the cutting action, as the rollers are held away from contact with the pin. As the tool is rotated into the position shown on FIG. S, the rollers will come into contact with the larger part of the pin and, by the resulting cam action, will prevent undesirable contact between the cutters and the smaller part of the pin.

As the operation proceeds, continued rotation of the tool will result in the high spots being removed until both the rollers and the cutters are making contact simultaneously. At his point, the crankpin will be perfectly round and further removal of material will be prevented by the selection and use of spacers 16 of correct thickness.

The foregoing specification describes a preferred embodiment of the tool, wherein ball bearings have been utilized as rollers, in order to facilitate ease of operation, it should be obvious, however, that other forms of rollers, or even projecting, nonrotating elements could be used to perform the function of the illustrated and described means. Also the cutters as shown may be replaced by abrasive elements or hones, and further modifications may be made within the spirit and intent of Title 35 United States Code, Section l I2, Par. 3.

lclaim:

l. A shaft-truing device comprising a pair of substantiallyr equiform body members adapted to form a shaft-encircling tool provided with shaft-contacting means and materialremoving means, wherein the improvement comprises, resilient body connecting means, diametrically opposed shaftcontacting means and diametrically opposed material-removing means, the diametrical axes of said shaft-contacting means and said material removing means being substantially normal to one another and the combination of said axes being substantially symmetrical with reference to a common median line through said body members.

2. A device as in claim I wherein said body-connecting means comprises spring-loaded bolts.

3. A device as in claim 1 wherein said shaft-contacting means comprises rotatably mounted elements.

4. A device as in claim l wherein said material removal `means comprises cutting elements.

S. A device as in claim l wherein said material removal means comprises abrasive elements.

6. A device as in claim l wherein said body members are

Claims

1. A shaft-truing device comprising a pair of substantially equiform body members adapted to form a shaft-encircling tool provided with shaft-contacting means and material-removing means, wherein the improvement comprises, resilient body connecting means, diametrically opposed shaft-contacting means and diametrically opposed material-removing means, the diametrical axes of said shaft-contacting means and said material removing means being substantially normal to one another and the combination of said axes being substantially symmetrical with reference to a common median line through said body members.

2. A device as in claim 1 wherein said body-connecting means comprises spring-loaded bolts.

4. A device as in claim 1 wherein said material removal means comprises cutting elements.

5. A device as in claim 1 wherein said material removal means comprises abrasive elements.

6. A device as in claim 1 wherein said body members are provided with means adapted to limit their degree of approach to a predetermined point.

7. A device as in claim 6 wherein said limiting means comprises annular members encircling said body-connecting means, and being located intermediate the individual body members of said pair.