US2755609A

US2755609A - Shaft grinding tool

Info

Publication number: US2755609A
Application number: US400303A
Authority: US
Inventors: Sylvester Cecil Lee
Original assignee: THELMA SYLVESTER
Current assignee: THELMA SYLVESTER
Priority date: 1953-12-24
Filing date: 1953-12-24
Publication date: 1956-07-24
Anticipated expiration: 1973-07-24

Description

4 Sheets-Sheet 1 Filed Dec. 24, 1953 Cecil Lee Sylves ter IN V EN TOR.

y 4, 3956 c. L. SYLVESTER SHAFT GRINDING TOOL 4 Sheets-Sheet 2 Filed Dec. 24, 1953 @ecil L98 Sylves ter IN V EN TOR.

HIS AGENT y 4, 1956 c. SYLVESTER SHAFT GRINDING TOOL 4 Sheets-Sheet 3 Filed Dec. 24, 1953 Cecil Lee Sylvester IN V EN TOR.

HIS AGENT July 24, 1956 c. SYLVESTER SHAFT GRINDING TOOL 4 Sheets-Sheet 4 Filed Dec. 24, 1953 Cecil Lee Sylvester INVENTOR.

BY Mme M2 HIS AGENT United States Patent SHAFT GRINDING TOOL Cecil Lee Sylvester, Brownsville, Tex., assignor to Thelma Sylvester, Brownsville, Tex.

Application December 24, 1953, Serial No. 400,303

Claims. (Cl. 51-241) This invention relates to improvements in crankshaft grinders and more particularly to crankshaft grinders suitable for grinding the crankpins of large industrial engines without removing the crankshaft from the engine.

Various crankshaft grinders for grinding crankpins have been proposed heretofore, but these for the most part, were so designed as to make their use impractical on large engines such as used in power plants, compressor units and the like.

The present invention enables the crankpin bearing surface on the crankshaft of an engine to be carefully and accurately ground without the removal of the crankshaft from the engine.

It is an object of the invention to provide a crankshaft grinder for grinding crankpins thereof, having an abrading element associated therewith for peripheral contact with the crankpin for grinding same, together with power means for rotating the abrading element longitudinally of the crankpin on the crankshaft.

Yet another object of the invention is to provide a crankpin grinder for a crankshaft which may be accurately and minutely adjusted from a remote point to remove any desired amount of material from the bearing surface of the crankpin and to provide a new, highly polished journal surface to complementarily fit a bearing element of a given size.

A still further object of this invention is to provide a crankshaft grinding device for grinding crankpins whereby the crankpin will be speedily and accurately ground to the correct size and the results of the grinding may be visually observed on a dial indicator during the grinding operation.

Still another object of this invention is to provide a crankshaft grinder for grinding crankpins whereby the crankpin of the crankshaft is centered within a frame on centering rollers which ride upon the radius of the fillet of the crankpin journal so as to grind crankpin true with respect to the original axis.

Yet another object of the invention is to provide a crankshaft grinding device for grinding crankpins that has a guide frame to insure the grinding of the cylindrical portion of the crankpin journal being perpendicular to the end flange faces.

Another object of the invention is to provide a pneumatically operated crankshaft. grinding device for. grinding crankpins that may be inserted through a side plate opening in the engine housing or through an engine cylinder.

Yet a further object of the invention is to provide a crankshaft grinder for grinding crankpins or other cylindrical objects, such as shafting and the like.

With these objects in mind and others that will manifest themselves as the description. proceeds, reference is to be had to the accompanying drawings, of which there are four sheets, in which:

Fig. 1 is a perspective view taken from above and from a side of the crank shaft grinder, and showing the handl thereof resting on a support member; I

ice

Fig. 2 is a diagrammatic side elevational view of the device in operating position to operate through a side of an engine housing, and showing a motion study in dashed out-line;

Fig. 3 is a top plan view of the device with parts broken away and shortened to show the details of construction;

Fig. 4 is a side elevational view of the device with parts broken away, shown in" section, and shortened to show the details of consfruction;

Fig. 5 is a fragmentary elevational view with parts shown in section, and with parts broken away, of a con necting rod throw and showing the centering rollers and the guide frame members in section;

Fig. 6 is a view similar to Fig. 5 but with the guide rollers shown in elevation and in the reverse position to that shown in Fig. 5;

Fig. 7 is a sectional view taken on the line 7-7 of Fig. 4, looking in the direction indicated by the arrows, and with a portion of the teeth of the rack and pinion shown in dashed out-line;

Fig. 8 is a perspective VlCW' through the handle support guide roller and the mounting therefor;

Fig. 8A is a fragmentary view partly in section and partly in elevation of the handle support guide rollers and the mounting therefor;

Fig. 9 is a longitudinal sectional view, with parts shown in elevation and with parts broken away and shortened, through the handle portion of the grinding apparatus showing the details of construction thereof;

Fig. 10' is a sectional view taken onthe line 10-10 of Fig. 4'; looking in the direction indicated by the arrows;

Fig. ll is a sectional viewtaken on the line 1111 of Fig. 9, showing the manner of retaining the thrust bearings in place;

Fig; 12 is a fragmentary top plan view of an adjusting screw fitted within the frame members for adjusting the abrading element relative to the surface of the connecting rod bearing throw of the crank shaft.

Fig. 13 is a sectional view takenon the line 13-13 of Fig. 12, looking in the direction indicated by the arrows; and

Fig. 14 is a fragmentary perspective view showing the universal mounting of the dial indicator standard.

With more detailed reference to the drawing, the numeral 20 generally designates the handle assembly, as is best illustrated in Fig; 9'. The inner end of this handle receives a slidable member 21 that is bifurcated as indicated at 22 to saddle over frame member cross bar 24, as will best be seen in Figs. 1 and 9.

The frame member cross bar 24 has a reduced end or tenon portion indicated at 26', which engages slotted end or mortise 28 of arcuate" side frame members 30. The side frame members 30 have parallel outer sides which are held in spaced relation by means of

bars

24, 32, 34 and36 that are rigidly secured in place by means of cap screws 38, as shown in Fig; 4, which pass through the respective bars and are screw-threaded into the arcuate side frame-members 30 so as tohold the side frame members in parallel relation. At' least one of the side frame members 30 is adjustable on the

respective bars

24, 32, 34, and 36, upon loosening of cap screws 38 to enable the movement of the respective bars relative to the side frame member, as will best be seen in Figs. 12' and 13, and which will be more fully described hereinafter. It is to bepointed out that the bars 24; 3'2, 3'4, and 36 are of a selected, substantially correct length and only small adjustment is necessary between the bars an'd the respective side members; The side frame members 30 each haveribsi 40' attachably' secured thereto by means of cap screws 42, as will bestbe seen in Figs. 3 and 4, so as to maintain: the: arcuate side frame members 30 against spreading outwardly. Each: of the ribs 40 has an opening formed therethrough to permit relative sliding movement between arcuate side frame members and cross bar 34, when it is desirable to adjust the arcuate side frame members 3! longitudinally of the

bars

24, 32, 34 and 36. The outer periphery of each side frame member 38 is transversely grooved at 33, 35 and 37 to receive the

respective cross bars

32, 34 and 36 in complementary relation.

Each of the respective cross bars has a slot 46 in each end thereof, as will best be seen from Fig. 3, to adjustably receive cap screws 38, and each of the side frame members 30 has radially disposed grooves 48 on the inner face thereof to complementarily receive stems 50 which have rollers 51 mounted thereon at approximately 120 degree spacing. Each of the rollers 51 are preferably ball bearing mounted on shaft 52, as will best be seen in Fig. 5. Each stem 50 is off-set at 53 near the inner end thereof so it may be reversed, as indicated in Fig. 6, with respect to the position as shown in Fig. 5. Each stem 50 is held in place by means of cap screws 54 which pass through a slotted portion thereof as indicated at 56.

The journal of the crank-throw is indicated at 58 and has a fillet 60 in each end thereof that is tangent to the cylindrical portion of journal 58 and to the inner side face 62 of bearing flange. The faces 62 are perpendicular to the cylindrical bearing face of journal 58, and therefore the faces 62 are normally parallel.

The handle assembly, generally designated at 20, com prises a tubular member 64 that has a key-way 66 at its inner end to complementarily receive a key 68 that interengages with rack bracket 70 that is secured against longitudinal movement by means of set screws 72, except when it is desired to adjust the bracket longitudinally of tubular member 64. With the bracket 70 held against relative rotary movement by key 68, the bracket may be moved longitudinally of the tubular member 64 and rack 74 may be held in fixed relation with respect to tubular member 64 by set screws 72, as will best be seen in Fig. 7. A longitudinally slidable member 21 is interfitted in close sliding relation with tubular member 64 and has a keyway 75 in which key 76 is fitted between the outer periphery of the member 21 and the inner diameter of tubular member 64 to hold the

members

64 and 21 against relative rotation. The slidable member 21 is welded or otherwise secured to an inner tubular member 78 that extends partially through tubular member 64 and has a set screw 80 passing through a sleeve 82 and into inner tubular member 78, so as to interlock the sleeve 82 therewith and against relative longitudinal and rotary movement. A hole 84 is provided in tube 64, as will best be seen in Figs. 4 and 10, to enable the removal of the screw 80.

The sleeve 82 is screw-threaded to receive threaded bolt 86, as will best be seen in Fig. 9. The screwthreaded bolt 86 is interlocked with a hand knob 88 that is pinned to screw-threaded bolt 86 by means of a pin 90 that passes through a knob 88 and through the screwthreaded bolt 86. Hand knob 88 has an inwardly extending projection 92 that has an annular groove 94 therearound, which groove is adapted to receive a pair of complementary arcuate keys 96, as will best be seen in Figs. 9 and ll. These keys prevent longitudinal movement in either direction of the hand knob 88.

A bearing 98 is provided within tubular member 64 near the outer end thereof and in close fitting relation with the projection 92 of hand knob 88. Set screws 100 pass through tubular member 64, bearing 98 and into arcuate keys 96 which prevent arcuate keys 96 from moving longitudinally so as to serve as a thrust bearing upon the turning of hand knob 88. The hand knob 88 is preferably calibrated in of an inch, or in such other indicia as desired to indicate the longitudinal movement of tubular member 64 relative to cross frame 24. The tubular member 64 has a suitable complementary mark, such as indicated at 102 so the indicia on hand knob 88 may be accurately read to enable the feeding of the grinding mechanism, generally designated at 104 into contact relation with journal 58 of the crank shaft or other cylindrical member being round.

The grinding element, as indicated in the present drawing, has a motor 106 that is preferably of the pneumatically actuated type, which motor is slidably mounted on bracket 70 for transverse sliding movement on keys 110 that are fitted in complementary relation with a key way formed in bracket 70 and base 198. A shaft 112 extends parallel along the side of tubular member 64 and has a knurled hand wheel 114 on the outer end and a pinion 116 on the inner end, which pinion meshes with rack 74.

The shaft 112 is journaled within a base 168 and is guided within a slot 169 in bracket 111, which bracket is secured near the outer end of tubular member 64, as is best seen from Figs. 1, 2 and 4. The motor 106 is clamped to base 168 by means of an upstanding clamp 118 having bolt 120 passing therethrough. The motor 186 has a right angle drive 122 at the inner end through which a shaft 124 passes, which shaft is threaded at each end, as will best be seen in Fig. 3; An abrading element, such as an emery, ruby, diamond, or other suitable abrasive stone 126 is bindingly secured on said shaft by means of a nut 128.

The motor 106 has a flexible conduit 130 attached thereto and extending to a point near the outer end of tubular member 64 where a suitable control valve 132 is mounted. The valve 132 is shown to be mounted on bracket 111 for the convenience of the operator. A suitable high pressure, pneumatic conduit may be attached to the valve 132 and to a suitable source of air supply. A dial indicator 134 is universally mounted on double clamps mounted on rod 136, which rod is off-set, as indicated in Fig. 14, and has a ball joint 138 on the lower end thereof. This is held in place by arms of a clamp 140 which enables further universal movement or turning movement to enable the dial indicator 134 to be moved from side to side so that the plunger 135 may be so directed as to constantly track with the land being cut by the abrasive element 126, thereby to give minute and accurate readings at all times of the amount of stock being removed by the abrading element 126.

The invention as illustrated in Figs. 1 and 2, is indicated as being used through a side of the crank case housing of an engine and has a bracket 142 secured to the side of an engine crank case housing 144 by means of bolts 146 that pass through slots 148 and are screw threaded into housing 144. The slots 148 enable the angle bracket 142 to be readily adapted to engines of various makes. A plate 150 is mounted on top of angle bracket 142 and is secured in place by cap screws 152. as will best be seen in Fig. 8. The plate may be raised or lowered by shims so as to properly position ball bearing rollers 154 at the proper height.

The rollers 154 are mounted on angularly diverging axes 156 so as to substantiate a V-block of a rolling character, as illustrated in Fig. 8A. The base 158, for these ball bearing rollers 154 is secured in place by bolts 160 which pass therethrough and are screw-threaded into plate 150. Suitable dowel pins 162 hold the base 158 in fixed relation to plate 150.

It is necessary that the peripheral face of abrading element 126 move absolutely parallel with respect to the journal 58, or other cylindrical surface being ground and while the frame bar 24 is normally secured to arcuate side frame members 3% at right angles thereto, it is sometimes necessary to adjust the frame bar member 24 with respect to arcuate members 30. A screw 164 has been provided, as shown in Figs. 12 and 13, which screw has an annular groove therearound, as indicated at 166. A half threaded hole 168 is formed in tenon 26, which hole is threaded slightly deeper than the length of'screw 164. A key 170, as indicated in Figs. 12 and 13, passes transversely through the annular groove 166 and extend'salong a slot 172 formed in the inner side of mortise '28, which slot 172 is slightly larger than half the outside diameter of screw 164, and is sufficiently' long to permit longitudinal sliding movement of cross frame member 24 relative to one of the arcuate side frame members 30, as will best be seen in Fig. 12. The tenon 26 has a slot 174 therein that is enlarged both longitudinally and transversely to permit longitudinal shifting of cross frame member 24 relative to arcuate side frame member 30, as will best be seen in Fig. 12. This arrangement will also enable vertical movement of tenon 26 relative to arcuate frame members 30, as will best be seen in Fig. 13.

The bracket 70 may be adjustably secured in place on tubular member 64 bymeans of set screws 72. The tubular member 64 is secured against longitudinal sliding movement on slidable member 21 by means of a set screw 77 which is threaded through bracket 70 and bindingly engages key 76. With the bracket secured in this manner, the abrading wheel 126 may be passed transversely of the face of the crankpin parallel to the original axis thereof.

A clamp bolt 107, as shown in Fig. 7', is provided to bindingly engage base members 108 with bracket 70. The bracket 111 is secured in place on tubular member 64 by means of set screws 113.

Operation.

To grind the crank throw of an engine of the large industrial type, which has side plates on the crankshaft housing, the desired plate or plates are removed and the connecting rod removed from the particular throw to be ground. Then cross frame bar member 24, and cross

bars

32, 34, and 36 are selected, to be of alength substantially the same or slightly shorter than the width of the crankpin journal to be ground, which journals are often twelve to fourteen inches in length. Arcuate side frame members 30 are then selected that have sufiicient arcuate size to pass over the throw of the crankshaft and have sufii'cient space to receive rollers. 51 mounted on stems 50, so that the rollers can be centered around crank throw or shaft 58. The frame cross bar member 24 and cross bars 32, 34, and 36 are bolted onto arcuate side frame members 30 by means of cap screws 38, and with the arcuate side frame members 30 moved outward against the inner'faces of the bearing flanges 62, and since these faces are parallel with each other and have a factory finish, and with the frame member crossbar 24 and cross bars 32, 34, and 36 tightly secured in place, the frame will present a rigid frame structure.

The adjusting screw 164 may be turned by insertion of a wrench thereinto, which wrench maybe turned until bar 24 is parallel with the top surface of the shaft. At least one of the frame members 30 is movable longitudinally of cross bar frame member 24, upon. loosening of bolts 38. When the proper adjustment hasbeen made, these bolts are again tightened tohold the parts fixed. in adjusted relation.

It is preferable to have the roller stems 50 calibrated along a side thereof, as indicated in Figs. 3 and 6, to aid in the setting of the rollers 51 with respect to the inner diameter of the arcuate side frame members 30. With the rollers 51 at each end of the journal or shaft 58 correctly adjusted about the diameter of the shaft 58,. which shaft may be in excess of twelve inches indiameter, as indicated in Fig. 5, and with the corners of the rollers 51 riding on factory formed fillets 60,. which usually are free of wear at approximately mid-point thereof, the unit comprising side frame members 30, framemembercross bar 24, cross bars 32, 34, and 36'will be maintained in a journaled relation with respect to the exact, true, original axis of the shaft, regardless of the wear. on the intermediate shaft 58 forming the bearing surface. With the frame of the grinding element thus fitted, and with the slidable member 21' bolted in place by means ofcap screw 23, as will best be seen in Figs. 4 and 9, and with the rack bracket 70 mounted on tubular stem 64, as is best seen in Figs. 4 and 7, the rack bracket is moved longitudinally therealong on key 68 to the desired adjusted position and set screws 72 are tightened to rigidly hold the rack bracket in place.

The motor 106, which carries the abrading element 126, may be moved toward or away from the peripheral face of the crank pin journal, by the turning of hand knob 88 the desired amount, whereupon, a set screw may be used to interlock the calibrated hand knob 88 with respect to the sleeve 64 to prevent rotary movement of the knob, thereby holding the abrading element in a fixed, radial relation relative to the crank pin journal while the abrading element is passed longitudinally back and forth across the face thereof to bring the journal to the correct size.

For the most accurate truing of the crank pin journals, the rollers 51 should ride on the concave surface of fillets 60 so as to maintain the frame in true concentric relation to the original axis of the crank pin journal, or such other journal as is being ground. In this manner, the abrading elements are maintained in true relation. with respect to the fillets which are usually free of wear, thereby enabling the grinding of a concentric journal.

The dial indicator 134 mounted on rod 136, which rod is held in fixed relation with respect to the mounting thereof when set on its universal mounting with respect to bracket 140 (Fig. 14) and upon rotation of the shaft 58 at a relatively slow speed, the dial indicator will give the eccentricity of the shaft with respect to the original, true axis, and then, by carefully moving the dial indicator 134 from side to side by means of hand wheel 114, the high places on the shaft may be ascertained, to enable the initial grinding operation to be made by the grinding wheel 126. With the plunger or feeler element of the dial indicator 134 in circumferential alignment with the land" to be cut by the abrading element 126, the hand nut is turned so that the screw element 86 will move the tubular element 64 inward on slidable member 21, so the abrading Wheel 126 will engage the peripheral face of shaft 58, and by regulating the supply of air to the motor 106 by means of valve 132, the high spots will be ground from the face of the shaft upon rotation of the shaft, as indicated in Fig. 2, and with a centering rest 154 bolted to the crank case housing as indicated. in Fig. 8, the rollers 154 will permit inward and outward movement of the tubular element 64 in a pattern, such as indicated in Fig. 2.

Slots 143 are provided in angular member 142 to permit relative adjustment longitudinally along the face of the opening of crankshaft housing 144.

The present device is designed to grind more than onehalf of the width of the crankpin bearing surface by the abrading element 126, on one end of the shaft 124. When the peripheral face of shaft 58 has been ground to a uniform diameter with respect to the original, true axis of the shaft, the abrading wheel is then removed from that particular end of the shaft and fitted on the opposite end of the shaft where it is secured in place by means of nut 128, and the dial indicator 134 is shifted on universal ball joint 138 so that the plunger 135 will track with the land being ground, and the operation of grinding the high spots from the shaft is repeated until the shaft is brought uniformly to the same diameter of the first portion that was ground, and since the rack 74 permits movement over more than one-half the width of the crankpin bearing face, the shaft 58 may be brought to uniform diameter throughout the entire width of the cylindrical bearing surface in this manner. Since the shaft is trued to the original axis of the bearing, the stem 50 may be removed from the radial slots 48, in arcuate side frame members 30 and the stems reversed to occupy the position as. shown in Fig. 6, with the peripheral face of rollers 51 engaging a true cylin drical bearing surface of the shaft 58 that has been trued with respect to the original axis, and with the arcuate side frame members 30 adjusted with respect to shaft 58 the fillet 60 may be ground true with respect to the original axis of the shaft 58, and the lower end of the fillet feathered so as to obviate any abrupt shoulder, thereon, and the fillet 60 may be ground truly tangential with the face 62 on the bearing flange; in this manner a grinding job may be performed on the crankshaft within the engine with substantially the same amount of accuracy as when originally ground at the factory. When a shaft is ground in the manner described above, the shaft is trued with respect to the original axis by having the guide rollers 51 roll on the arcuate surface of the fillets 6t) and the roller is held in guided relation by the contact of the arcuate side frame members 3% with the inner parallel faces 62 of the hear ing flanges and since the measuring that is performed on the shaft 58 is such that the high and low spots of the shaft may be determined in advance of the actual grinding operation and so noted, then the actual grind ing operation is performed under minute control, with the dial indicator indicating the depth of the cut of the abrading element, a minimum of metal may be removed from the shaft to give a true cylindrical bearing sur face on the shaft that is cylindrical with respect to the original axis of the shaft.

While the invention has been described and illustrated in some detail with respect to grinding the throws of cylindrical crankshafts, it is to be pointed out that it may be successfully used for surfacing and polishing shafts, such as line shafts and the like that are rotated either on centers or on journaled bearings, by ones fitting the grinding device about a shaft with the rollers 53. sub stantially centering the shaft within arcuate side frame members 30, whereupon the abrading element 126 may be moved longitudinally along the shaft by means of hand wheel 114, and the handle adjusted on rollers 154, or the entire device may be urged manually longitudinally of the shaft as the grinding and polishing operation is performed, since the outer sides of the arcuate side frame members 30 will not be in engagement with flanges, with the dial indicator indicating the amount of stock being removed as it is removed from the shaft.

It is to he understood that changes in the details of construction may be made without departing from the spirit of the invention or the scope of the appended claims.

Having thus described the invention, what is claimed 1. A shaft grinding tool comprising: a pair of side frame members having a throat to partially encircle a shaft, cross bars connecting said side frame members and attachably secured thereto, a stem attached to one of said cross bars and extending outwardly therefrom substantially at right angles thereto, a second stem complementarily engaging said first mentioned stem and being slidably mounted thereon in longitudinal sliding rela tion with respect thereto, a transverse bracket secured to said second mentioned stem near the end adjacent said side frame members, a base mounted on said bracket for longitudinal sliding movement with respect thereto, a motor mounted on said base for movement therewith, an abrading wheel mounted on said motor for rotation thereby, guide means mounted on each of said side frame members and projecting inwardly at spaced intervals around the inner surface of said throat for journaling a shaft therein for turning movement with respect thereto, means for adjustably moving said base carrying said motor longitudinally along said bracket, and further means for adjustably moving said second mentioned stem and said motor carrying said abrading wheel longitudinally of said first mentioned stem.

2. The device as defined in claim 1; which includes parallel outer faces on said side frame members, which parallel faces are adapted to fit in bearing relation with parallel faces of the flange at each end of the crank shaft journal being ground.

3. The device substantially as set forth in claim 2; wherein, said side frame members, in addition to being attachably secured to the cross bars, are adjustably secured thereto, and wherein the guide means are rollers.

4. The device as defined in claim 2, wherein, said second stem is tubular and is telescoped over said first mentioned stem and guide rollers mounted below and in contact relation withsaid tubular stem to support said tubular stem for reciprocating movement.

5. A crank shaft grinding tool adapted to grind the journal of a crank shaft which journal has a flange at each end thereof, the faces of which flanges are parallel and each has radial fillets thereon: which tool comprises a pair of spaced apart side frame members having the outer end faces thereof parallel, said side frame members each having an open throat formed therein, the outer end faces of each of said side frame members being adapted to fit in abutting relation with the respective parallel flanges of the crank shaft being ground when the tool is fitted thereon, cross bars connected to said side frame members and attachably secured thereto, a stem attached to one of said cross bars and extending outwardly therefrom at substantially right angles thereto, a second stem mounted on and being slidable with respect to said first mentioned stem, a transverse bracket secured to said second mentioned stem, a rack mounted on said bracket, a base mounted on said bracket for sliding movement longitudinally of said bracket, a motor mounted on said base, a pinion rotatably mounted on said base and interengaging said rack on said bracket, a shaft connected to said pinion and extending outward therefrom, means on said shaft for rotating said pinion, an abrading wheel mounted on said motor, and means for adjusting said motor carrying said abrading wheel longitudinally with respect to said first mentioned stem.

6. The device substantially as set forth in claim 5, wherein; means are provided for selectively locking said first mentioned stem and said second mentioned stem against relative longitudinal movement.

7. The device as defined in claim 5, which includes indicator means mounted on said transverse bracket in peripheral alignment with said abrading wheel and rearwardly thereof, in position to ride on the surface of the shaft being ground.

8. A crank shaft grinding tool adapted to grind the journal of a crank shaft, which journal has a flange at each end thereof, the faces of which flanges are parallel and each having radial fillets thereon: which tool comprises a pair of spaced apart side frame members, the outer end faces of said side frame members being parallel, cross bars attachably and adjustably connecting said side frame members together, a stern attached to one of said cross bars and extending outwardly therefrom substantially at right angles thereto, a second stem mounted and being in sliding relation with respect to said first mentioned stem, a bracket secured to said second mentioned stern, a motor having a shaft, said motor being mounted on said bracket of said second mentioned stem, roller centering means mounted on said side members and adapted to be engaged with the fillets of the crank shaft being ground, so as to center said side frame member with respect to the shaft being ground, an abrading wheel secured on the shaft of said motor, means for transversely adjusting said motor carrying said abrading wheel with respect to the axis of said first mentioned stem, and means for moving said motor, carrying said abrading wheel, longitudinally of said first mentioned stem.

9. The device substantially as set forth in claim 8, wherein; means is provided for adjusting the angularity of at least one of said cross bars with respect to the parallel faces of said side frame members.

10. A crank shaft grinding tool adapted to grind the journal of a crank shaft which journal has a flange at each end thereof, the faces of which flanges are parallel and each has radial fillets thereon: which tool comprises a pair of spaced apart side frame members each having an open throat, the outer end faces of each of said side frame members being parallel, cross bars connecting said side frame members and attachably and adjustably secured thereto, a stem attached to one of said cross bars and extending outwardly therefrom substantially at right angles thereto, a tubular member telescoped over said stern and slidably mounted thereon in longitudinal sliding relation with respect thereto, a bracket secured to said tubular member near the inner end thereof, a pneumatic motor, which motor has a shaft, said motor being slidably mounted on said bracket for transverse movement relative to the axis of said tubular member, guide means mounted on each of said side frame members for journaling a shaft to be ground therein for turning movement with respect thereto, an abrading wheel secured to the shaft of said motor, means for adjustably moving said motor transversely with respect to said tubular member, and means for adjustably moving said motor carrying said abrading wheel longitudinally of said stem.

11.' A crank shaft grinding tool as set forth in claim 10, wherein; a roller guide means mounted below and in bearing relation with said tubular stem to support said tubular stem for reciprocating movement.

12. A crank shaft grinding tool adapted to grind the journal of a crank shaft which journal has a flange at each end thereof, the faces of which flanges are parallel and each has radial fillets thereon: which tool comprises a pair of spaced apart side frame members each having an open throat, the outer end faces of each of said side frame members being parallel, cross bars connecting said side frame members, said cross bars being attachably and adjustably secured to said side frame members, a stem attached to one of said cross bars and extending outwardly therefrom substantially at right angles thereto, a tubular member telescoped over said stern and slidably mounted thereon for longitudinal movement with respect thereto, a bracket secured to said tubular member near the inner end thereof, a motor slidably mounted on said bracket for transverse movement relative to said tubular member, guide means mounted on each of said side frame members for journaling a shaft therein for turning movement with respect thereto, an abrading wheel on said motor, means for adjustably moving said motor transversely with respect to said tubular member, a calibrated hand knob for adjustably moving said motor carrying said abrading wheel longitudinally of said stem, and

means on said tubular member to indicate the relative 5 position of said hand knob.

13. A crank shaft grinding tool as set forth in claim 12, wherein; a shaft mounted transversely with respect to the axis of said tubular member and being connected in driven relation to said motor and has the ends thereof extending outwardly therefrom, each end of said shaft being adapted to receive an abrading wheel thereon, and means for securing an abrading wheel selectively to an end of said shaft for rotation therewith.

14. A crank shaft grinding tool substantially as set forth in claim 13; wherein, the peripheral face of said abrading wheel adapted to engage the shaft being ground, with the axis thereof substantially parallel with the axis of said shaft being ground.

15. A crank-shaft grinding tool for grinding journals of a crank shaft, each of said journals having a flange at each end thereof, the faces of which flanges are parallel, a radial fillet intermediate each of said flanges and the respective journals, comprising: a pair of side frame members each having an open throat, the end faces of each of said side frame members adjacent said flanges being parallel and adapted to fit in bearing relation with said flanges, and which side frame members partially encircle said shaft, ribs on the periphery of said side frame members and extending outwardly therefrom, cross bars connecting said side frame members and attachably secured thereto, a stem attached to one of said cross bars and extending outwardly therefrom substantially at right angles thereto, a second stem complementarily engaging said first mentioned stem and being slidably mounted thereon in longitudinal sliding relation with respect thereto, a transverse bracket secured to said second mentioned stem near the inner end thereof, a base mounted on said bracket for longitudinal sliding movement with respect thereto, a motor mounted on said base for movement therewith, an abrading wheel mounted on said motor for rotation thereby, guide means on each of said side frame members and projecting inwardly into said throat at spaced intervals around the periphery thereof for journaling a shaft therein for turning movement with respect thereto, means for adjustably moving said base carrying said motor longitudinally along said bracket, and further means for adjustably moving said second mentioned stem and said motor carrying said abrading wheel longitudinally of said first mentioned stem.

References Cited in the file of this patent UNITED STATES PATENTS 879,277 Landis Feb. 18, 1908 2,109,292 Hribar Feb. 22, 1938 2,321,081 Hanrahan June 8, 1943