US3893267A

US3893267A - Honing tool

Info

Publication number: US3893267A
Application number: US366986A
Authority: US
Inventors: Clyde A Swinehart; Lyle Stanford Hasty
Original assignee: MWA Co
Current assignee: MWA Co
Priority date: 1973-06-04
Filing date: 1973-06-04
Publication date: 1975-07-08
Anticipated expiration: 1992-07-08
Also published as: CA975562A

Abstract

A honing tool having abrasive units adjustably mounted on a mandrel for honing cylindrical bores. The abrasive units comprise abrasive stones or sticks removably secured to carriers by wedge type clamps. Each carrier has a replaceable expansion rod or wire and also has a key providing a pair of retaining lips engageable in keyways on the mandrel to prevent the abrasive unit from separating from the mandrel when the mandrel is retracted.

Description

United States Patent [1 1 [111 3,893,267

Swinehart et al. July 8, 1975 [541 HONING TOOL 2,580,328 12/1951 Sunnen 51/338 Inventors; Clyde A. Swinehart, Unicio; Lyle Stanford Hasty, Erwin, both of Tenn.

Assignee: MWA Company, Owosso, Mich.

Filed: June 4, 1973 Appl. No.: 366,986

[52] U.S. Cl. 51/338 [51] Int. Cl. B2411 9/02 [58] Field of Search 511338-352 [56] References Cited UNITED STATES PATENTS 1,797,837 3/1931 Prange 51/339 2,195,055 3/1940 Wallace 51/338 Primary Examiner0thell M. Simpson Attorney, Agent, or FirmWhittemore, Hulbert & Belknap [57] ABSTRACT A honing tool having abrasive units adjustably mounted on a mandrel for honing cylindrical bores. The abrasive units comprise abrasive stones or sticks removably secured to carriers by wedge type clamps. Each carrier has a replaceable expansion rod or wire and also has a key providing a pair of retaining lips engageable in keyways on the mandrel to prevent the abrasive unit from separating from the mandrel when the mandrel is retracted.

3 Claims, 9 Drawing Figures SHEET I ll I s I,

rlll.

HONING TOOL BACKGROUND AND SUMMARY OF THE INVENTION This invention constitutes an improvement over the honing mandrel disclosed in US. Pat. No. 2.419.136. One of the advantages of the present invention is that the entire abrasive unit, including the carrier and ex pansion wire. does not have to be thrown away when the abrasive stones wear out because the abrasive stones are removably mounted on the carriers. In ac cordance with the preferred construction about to be described, a pair of abrasive sticks are mounted in spaced recesses on the carrier and are removably held in place by a wedge type clamp. When the abrasive wears out, it alone needs to be replaced, there being no need to discard the carrier and the clamp. The expansion rod or wire and the key are also removably secured to the carrier and likewise may be replaced if necessary.

As a further feature of the invention, the honing tool is designed to permit the use of abrasive sticks of varying length, depending upon the requirements of the particular operation and the length of abrasive sticks available. In addition, the honing tool about to be described has been designed to afford more uniform abrasive wear and better cutting action.

In the drawings:

FIG. 1 is a side elevational view with parts broken away and in section of a honing tool embodying my invention.

FIG. 2 is an end view of the honing too] shown in FIG. 1, taken on the line 22 thereon.

FIG. 3 is a sectional view taken along the line 33 in FIG. 1.

FIG. 4 is a sectional view taken on the line 44 in FIG. I.

FIG. 5 is a longitudinal sectional view taken on the line 55 in FIG. 2.

FIG. 6 is a plan view of the carrier and expansion rod sub-assembly which form parts of an abrasive unit.

FIG. 7 is a sectional view taken on the line 7-7 in FIG. 6.

FIG. 8 is a longitudinal sectional view of the mandrel and is similar to FIG. 5 but with the abrasive units removed.

FIG. 9 is a sectional view taken on the line 99 in FIG. 8.

Referring now more particularly to the drawings. the honing tool is generally designated 10 and comprises an elongated mandrel 12 supporting a pair of abrasive units I4 for radial adjustment.

The abrasive units 14 each includes an elongated carrier 16, a pair of elongated abrasive sticks IS, a wedge type clamp or plate for removably securing the abrasive sticks to the carrier, an expansion rod or wire 22 removably secured to the carrier and a key 24 also removably secured to the carrier.

The carrier has a generally flat radially outer surface 26 provided with a pair of longitudinally extending, laterally spaced, parallel substantially V-shaped recesses 28. The sides of each recess preferably form a 90 angle as clearly seen in FIGS. 2, 3 and 7 to receive the corner portions of the abrasive sticks 18 which are of rectangular cross section throughout their length. The recesses 28 are turned to an angle such that the outer corners 19 of the sticks are presented to the bore for grinding. The adjacent surfaces 2I ofthe sticks 18 extending from the grinding corners I9 diverge in a radially outward direction. The abrasive sticks 18 may extend throughout the full length ofthe carrier or two or more abrasive stick segments each of shorter length may be clamped end to end in each recess instead of one full length stick as more fully described hereinafter.

The abrasive sticks 18 are removably secured to the carrier by a wedge type clamp which may extend the full length of the carrier and is here shown as being in the form of an elongated flat plate 20 having the longitudinal

parallel side edges

32 and 34 beveled as shown at the same angle as the diverging surfaces 21 of the abrasive sticks for full surface contact therewith. The contact between the

edges

32 and 34 of plate 20 and the diverging surfaces 21 of the sticks provides a wedge type clamp to more firmly hold the sticks in their recesses. The wedge plate 20 is secured to the carrier by screws 36 which thread into holes 37 in the carrier. Preferably the wedge plate 20 is of a width such that when screwed down in contact with the abrasive sticks as shown in FIGS. 2, 3 and 5, it is spaced from the top surface 26 of the carrier so that the full clamping pres sure of the plate 20 is applied to the abrasive sticks.

It is not necessary to use abrasive sticks which extend the full length of the carrier. One or more abrasive stick segments of less total length or the same total length as the carrier may be used if desired. The dotted lines 38 in FIGS. 1 and 5 indicate the abutting ends of two abra sive stick segments one of which may be two inches long and the other four inches long, assuming a six-inch length carrier. Obviously other length segments may be employed.

It is also not necessary that the wedge plate 20 be a single member extending the full length of the carrierv It too may comprise one or more segments of less total length or the same total length as the carrier. In FIGS. I and 5 the dotted lines 38 indicate the use of two wedge plate segments abutting end to end. Obviously more than two wedge plate segments could be employed. On the other hand, if the abrasive segments in the two recesses are shorter than the carrier, a single wedge plate segment of the same length as the abrasive segments may be used.

The expansion rod or wire 22 is an elongated element having one end extending into an elongated longitudinally extending hole or socket 42 in the rear end of the carrier. The rod end is removably held in the socket by one of the screws 36 used to secure the wedge plate 20 to the carrier. The other end of the expansion rod 22 terminates in a radially outwardly extending part 44.

The carrier 16 has a generally flat radially inner surface 45 which is inclined away from the radially outer surface 26 from the rear end to the front end of the carrier so that the carrier is thinner at the rear end than at the front end as shown. The inner surface 45 has a transverse recess 46 extending entirely across the full width of the carrier in which an elongated plate or key 24 is secured. The ends of the key 24 project beyond the sides of the carrier to provide lips 50. The key 24 is removably secured in the recess 46 by screws 52.

The mandrel 12 is in the form of an elongated bar 49 having an elongated head 53 on which the abrasive units are mounted. The head has a pair of elongated diametrically opposite channels 54 which extend the full length of the head 53. The bottom surfaces 58 of the channels are flat and tapered or sloped from the rear end to the front end of the mandrel head in a direction toward the longitudinal axis of the head. The channels 54 are of the same width as the carriers to slidably re ceive the carriers and it will be noted that the inner surface 45 of each carrier is sloped relative to the outer surface thereof at the same angle as the bottom 58 of the channel 54 is sloped relative to the longitudinal axis of the head. Accordingly. when the carriers are seated in the channels as shown with the inner surfaces 45 in full surface contact with channel bottoms 58, the abrasive sticks extend parallel to the mandrel axis and will remain parallel thereto throughout the range of radial adjustment of the carrier units which is accomplished by moving the carriers lengthwise in the channels.

The mandrel head is also formed with a pair of grooves or keyways 62 which extend laterally outwardly from the base of each channel 54. These grooves extend rearwardly from the forward end of the mandrel. The lips 50 of the key 24 of each carrier ex tend into the grooves 62 as shown in FIG. 2 to prevent the carriers from flying out or separating from the mandrel when it is withdrawn from the work. The length of the grooves 62 is sufficient to accommodate the full range of axial movement of the carriers.

The mandrel head 53 has a longitudinally extending groove 70 in the bottom 58 of each channel 54. The groove extends from the front end of the head and terminates in the bar portion 49 of the mandrel 12 as seen in FIG. 1. The grooves 70 are of a size to slidably receive the expansion rods or wires 22.

A suitable chuck 72 may be used to rotate the honing tool. The chuck 72 has a driving sleeve 74 adapted to receive the end of the bar 49 of the mandrel. The bar 49 can slide longitudinally in the sleeve 74 and has a screw or other projection 76 extending into a longitudinal slot 78 in the sleeve causing the bar 49 to rotate with the sleeve but permitting the bar to slide longitudinally the length of the slot. The bar 49 of the mandrel may be connected to an axially shiftable adjusting member 80 in the sleeve as by means of a bayonet type connection 82.

FIG. 1 shows the terminal parts 44 of the expansion rods 22 clamped against the end of the driving sleeve 74 by an i .urned annular flange 84 on a cap 86 secured on the sleeve 74 as by threading. As seen in FIG. 4, the flange 84 of the cap 86 has the diametrically opposite notches 88 which, when the cap 86 is rotated counterclockwise from the FIG. 4 position, will clear the terminal parts 44 of the expansion rods 22 to permit the expansion rods to be released.

It will be apparent that rotation of the chuck 72 will rotate the honing tool. The diameter of the honing tool may be varied by axially shifting the adjusting rod 80 to similarly move the mandrel causing the carriers 16 to slide either up or down the sloped channels 54 in the mandrel head.

The recesses 28 in the carriers 16 are turned to an angle such that the corners of the rectangular sticks are presented to the bore for grinding, resulting in better cutting action. More cutting edges are presented to the work because several sticks of small cross section. in this instance four, are employed rather than a smaller number, for example one on each carrier. of larger cross section. The abrasive sticks wear uniformly and when they wear out they may be readily replaced by removing screws 36 and removing the clamping plate 20. The carriers themselves last indefinitely. Expansion rods or wires may also be replaced readily and without the need to change carriers by merely backing off one of the screws 36. The carriers can of course he standardized and used on other mandrels of different size. The retaining key 24 can also be replaced by simply removing screws 52. The carriers also permit infinite variation of abrasive stick length up to the length of the carrier itself.

What we claim as our invention is:

1. An abrasive unit adapted to be mounted on a honing tool mandrel. comprising an elongated carrier hav ing a pair of elongated laterally spaced recesses in the outer face ofsaid carrier extending lengthwise thereof. an elongated abrasive stick of rectangular cross section in each recess. said recesses being V-shaped and of right angle cross section. each of said recesses being arranged to receive a corner of an abrasive stick and present the opposite corner thereof to the surface of a cylinder bore for grinding. the adjacent surfaces of said sticks extending from the grinding corners thereof diverging in a radially outward direction. means for releasably holding said abrasive sticks in said recesses comprising a wedge plate removably secured to said carrier between said recesses in wcdging contact with said sticks. said wedge plate having its opposite longitudinal edges inclined so as to have substantially full sur face-to-surface contact with said adjacent surfaces of said sticks, an expansion rod. means releasably securing said expansion rod to one end of said carrier. a transverse recess in the undersurface of said carrier at the opposite end thereof. an elongated transverse key disposed in said recess with its opposite ends projecting beyond the sides of said carrier to provide retaining lips for retaining said carrier on the honing tool mandrel, and means releasably securing said key in said transverse recess.

2. An abrasive unit adapted to be mounted on a honing tool mandrel, comprising an elongated carrier having a pair of elongated laterally spaced recesses in the outer face of said carrier extending lengthwise thereof, an elongated abrasive stick in each recess, means for releasably holding said abrasive sticks in said recesses comprising a wedge plate removably secured to said carrier between said recesses in wedging contact with said sticks. an elongated key. and means releasably securing said key to the front end of said carrier crosswise thereof and with the opposite ends of said key projecting beyond opposite sides of said carrier to provide retaining lips for retaining said carrier on the honing tool mandrel.

3. An abrasive unit adapted to be mounted on a honing tool mandrel, comprising an elongated carrier having a pair of elongated laterally spaced recesses in the outer face of said carrier extending lengthwise thereof, an elongated abrasive stick in each recess, means for releasably holding said abrasive sticks in said recesses. an elongated key. and means releasably securing said key to said carrier crosswise thereof and with the opposite ends of said key projecting beyond opposite sides of said carrier to provide retaining lips for retaining said carrier on the honing tool mandrel.

Claims

1. An abrasive unit adapted to be mounted on a honing tool mandrel, comprising an elongated carrier having a pair of elongated laterally spaced recesses in the outer face of said carrier extending lengthwise thereof, an elongated abrasive stick of rectangular cross section in each recess, said recesses being V-shaped and of right angle cross section, each of said recesses being arranged to receive a corner of an abrasive stick and present the opposite corNer thereof to the surface of a cylinder bore for grinding, the adjacent surfaces of said sticks extending from the grinding corners thereof diverging in a radially outward direction, means for releasably holding said abrasive sticks in said recesses comprising a wedge plate removably secured to said carrier between said recesses in wedging contact with said sticks, said wedge plate having its opposite longitudinal edges inclined so as to have substantially full surface-to-surface contact with said adjacent surfaces of said sticks, an expansion rod, means releasably securing said expansion rod to one end of said carrier, a transverse recess in the undersurface of said carrier at the opposite end thereof, an elongated transverse key disposed in said recess with its opposite ends projecting beyond the sides of said carrier to provide retaining lips for retaining said carrier on the honing tool mandrel, and means releasably securing said key in said transverse recess.

2. An abrasive unit adapted to be mounted on a honing tool mandrel, comprising an elongated carrier having a pair of elongated laterally spaced recesses in the outer face of said carrier extending lengthwise thereof, an elongated abrasive stick in each recess, means for releasably holding said abrasive sticks in said recesses comprising a wedge plate removably secured to said carrier between said recesses in wedging contact with said sticks, an elongated key, and means releasably securing said key to the front end of said carrier crosswise thereof and with the opposite ends of said key projecting beyond opposite sides of said carrier to provide retaining lips for retaining said carrier on the honing tool mandrel.

3. An abrasive unit adapted to be mounted on a honing tool mandrel, comprising an elongated carrier having a pair of elongated laterally spaced recesses in the outer face of said carrier extending lengthwise thereof, an elongated abrasive stick in each recess, means for releasably holding said abrasive sticks in said recesses, an elongated key, and means releasably securing said key to said carrier crosswise thereof and with the opposite ends of said key projecting beyond opposite sides of said carrier to provide retaining lips for retaining said carrier on the honing tool mandrel.