US1416462A

US1416462A - Grinding machine

Info

Publication number: US1416462A
Application number: US247632A
Authority: US
Inventors: Bengt M W Hanson
Original assignee: Pratt and Whitney Co Inc
Current assignee: Pratt and Whitney Co Inc
Priority date: 1918-07-31
Filing date: 1918-07-31
Publication date: 1922-05-16
Anticipated expiration: 1939-05-16

Description

B. M. w. HANSON.

GIRINDING MACHINE. APPLICATION FILED IULY3II 1918.

- Patented May 16, 1922.

@I I ITQIIIIIIJIII.II-QIIIJ.INI III-; .I I. I I I IIIII B. M. W. HANSYON. GRINDING MACHINE.

APFLICATION FILEDgJYULYSl, 1918. I

vPatented May 16, 1922.

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Hummm VHHIIHHHHHIL'HIHIMIIIHIIIIIII Ill B. M. W. HANSON.

GRINDING MACHINE.

APPLICATION HLED IULYS, |918. 941 6,462. Patented May 16, 1922..

' 8 SHEETS-SHEET 3.

Q .5 4 E55' 5e B. M. w. HANSON. GRINDING MACHINE.

APPLICATION FILED JLILYSI. |918.

Patented May 16,1922.

SHEETS-winmix.

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A Toen/Ey' B. IVI. W. HANSN.

GRlNDING MACHINE. APPLICATION FILED IuIYaI, 191s.

Patented May 16, 1922.

8 SHEETS-SHEET ,5.

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GHINDING MACHINE.

APPLICATION FILED yJULIIaI, Iglla.

Patented May 16, 1922.

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.Endung-,1552s.

B. IVI. W. HANSON.

GRINDING MACHINE.

APPLICATION man 1ULY31. 191s.

'Patented May 16, 1922.

8 SHEETS-SHEET 7.

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B. wi. W. HANSON.

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APPLICATION FILED JULY3I. l9l8.

Patented May 16, 1922.

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BENQ-T M. W. HANSON,0F HARTFORD, CONNECTICUT, ASSIGNOR TU PTT 8s WHITNEY COMBANY, OF NEW-YORK, N. Y., A. CORPGRATION 0F NEW il ma. f

@BINDING MACHINE.

faience..

Specication of Letters Patent. patinte@ May 169 11922@ Application filed July 31, 1918. Serial No. 247,632.

To all whomft may concern.'

Be it known that L-BENGT M. W. Hanson,- a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Grinding Machines, of which the following is a speclfication.

The invention relates especially to grinding machines which are adapted for grinding long cylindrical or approximately cylindrical bodies, such for instance as gun barrels. A machine embodying the invention is provided with a broad faced wheel having al width equal to or exceeding the length of the part of the work to be ground.

One of the objects of the invention is to provide in a machine of the type specified, improved means for supporting the work and for effecting relative movement to bring the work and the wheel into ope'rative engagement. Preferably, as will later more fully appear, the wheel is rotatable about a fixed axis and the work sup-port is movable toward or away from the wheel. In accordance with the invention I provide means whereby the work support may be moved slowly through small distances to eect adjustment and feeding, and I also provide supplemental means whereby the work support may be moved independently of the feed mechanism rapidly through a relatively great distance to remove the work support far enough from the' wheel to permit finished work to be removed and new work to be inserted.

Another object of the invention is to pro' vide in a machine having a broad faced grinding wheel, an improved work holding means including a system of back-rests whereby the work may be supported and steadied during grinding at a number of different points.

A further object of the invention is to provide improved means whereby the work may be given a small reciprocatory longitudinal movement during grinding.

A still further object of the invention is to provide, in combination with o ther features of the machine, an improved guard for the grinding wheel, the guard being bodily- Another object of the invention is to provide improved means for delivering water to the thereof.

Still another object of the invention is to provide in combination with other features of the machine, an improved means for dressing the wheel in conformity with the character and shape of the worla to be ground.

Still further objects of the invention will be app-arent from the following specification and claims.

In the accompanying drawings I have shown the embodiment of the invention which I now deem preferable, but it will be understood that the drawings are to be considered as merely illustrative and are not to be construed as defining or limiting the scope of the invention, the accompanying claims/being relied upon for that purpose.

Of the drawings:

Fig. 1 is a front elevation.

Fig. 2 is a plan view.

Fig. 3 is an end view on an enlarged scale taken from the left, the motor being removed.

grinding wheel along the entire width' Fig.. 4 is an end view on the same scale Fig. 8 is anenlarged front view showing the mechanism for swinging the work carry ing frame.

Fig. 9 is a fragmentary sectional lView taken along the line 9-9 of Fig. 5.

Fig. 10 is a fragmentary sectional view taken along the line 10-10 of Fig. 3.

Fig. 11 is a detail view on an, enlarged scale showing two of the back-rests.

Fig. 12 is afragmentary front view, partly in section, and' showing-the gearing for operating the wheel dressing device.

Fig. '13` is an end view,l partly in section, of the mechanism shown in Fig. 12.

Fig. 14 is a fragmentary sectional view taken along the line 14-14 of Fig. 13.

Fig. 15 is a plan View.l of a part of the wheel dressing mechanism detached from the other parts of the machine.

Fig. 16 is a front elevation ofthe mecha-r nism shown in Fig. 15.

Fig. 17 is a detail view of the former.

A machine embodying the invention com-v prises a main framefl upon which is mounted a grinding wheel 2 which is rotatable about a longitudinal horizontal axis. The wheel has a broad working face which preferably extends the full length of the work to be ground. Mechanism is provided for rotating the wheel, this consisting inthe present instance of an electric motor 3 mounted on an extension 4 of the main frame. The machine is primarily intended for grinding work which is circular in cross section, but its use is not necessarily` limited to the grinding of work of this character. A gun barrel vmay be taken as an example of the work for which the machine is best adapted. There is provided a suitable work support for holding the work to be ground, which for purposes of illustration will be considered tobe a gun barrel such as shown at A. Preferably the work support comprises centers carried respectively, by a headstock 5 and a tailstock 6, which are longitudinally a table 7. Means is provided for causing relative approaching and separating move- .ments between the Work support and the wheel for initially bringing the work into contact with the wheel and for feeding. In order to provide a rigid support for the wheel which will hold it against vibration, and in order that the wheel may be directly connected with the motor 1 prefer to mount the wheel in fixed bearings and to move the work support Vtoward and from the wheel. When the wheel is thus'mounted the table 7 is carried by a frame 8 which is moved to bring the work into or out of t5 operative engagement with the wheel. Preferably this frame is pivoted near its bottom to the main frame 1, as, for instance, by

means of

trunnions

9 and 10.

Having now briedy outlined some of the more important elements of themachine, 1 will now proceed to a more detailed descriptlon of the several parts.

As shown most clearly in Fig. 6there are provided two

bearin brackets

11 and 12 which project upwar from the main frame 1 and whichcarry a rotatable spindle 13. Secured 'to this spindle, by any usual or preferred means and positionedbetween the bearings, is the aforesaid din wheel 2. 'llhe motor 3 is mounted with its rive shaft 1t in alinement with the spindle 13, and` carried respectively` bythe spindle 13 and the shaft 141. are ilanges 15 and 16. 'llhe illanges are rovided respectively with opat positely projecting pins 17 and 18 and an adjustable along horizontal ways formed ony 1,41 efica- -many of the features of the invention the guard can. be of any usual or preferred construction, but I prefer a guard such as is shown in the drawings and will be described.

The guard is constructed in a manner to provide a high tensile strength which will enable it to resist breakagin case of breakage of the grinding wheel. Preferably this tensile strength is provided by forming the sides of the guard of sheet metal. Preferably in order that the guard` may be easily opened to permit access to the wheel it is formed with a top section which is readily separable from the bottom section.

As illustrated, the lower section comprises two similar oppositely

disposed end plates

20 and 21 positioned adjacent the bearing

brackets

11 and 12 respectively. These plates 2() `and 2l are connected by rods 22-which extend through suitable apertures in the plates, these apertures being spaced at intervals along the outer edges.v Preferably, as shown in Fig. 5, the portions a5 of the rods-22 between theplates are square.

A double sheet metal casing 23 is secured to these rods, this casing preferably consisting .extends rearward engaging the inner surfaces of the rods. The sheet metal is secured to the rods in any suitable manner, as, for instance, by means of rivets 24 extending through apertures in the rods. Preferably the

end plates

20 and 21 are provided with grooves, as shown in Fig. 6, into which the edges of the sheet metal 23 extend, thus n@ making a tight joint. Preferably the lower section of the guard is provided with drain apertures as shown at 23", 23a.

The upper section of the guard is constructed similarly to the lower section, this 1w upper section comprising

end plates

25 and 26 which are connected by rods 27. Secured to the rods 27 is a sheet metal' casing 28 similar to the sheet metal casn 23 already described. The two sections o' the guard l12o ter of a single wheel due to wear, I provide means whereby both sections of the wheel may be moved backward or forward.

The end plate 20 of the lower section of the guard is provided with

apertured ears

31 and 32 which carry a horizontal pin 33. The pin extends through a bearing aperture in the body part of the bearing bracket 11. rI`he opposite end plate 21 is provided with a horizontal lug 34 which its between lugs 35 carried by the bearing bracket 12 and a latch 36 pivoted to the bearing bracket at, 37. As shown in Fig. 3, the length of the pin 33 between the

ears

31 and 32 is considerably 15 greater than the width of the bearing bracket 11, thus permitting the pin to slide in the aperture. The construction at the right-hand end also permits forward and backward movement and the entire lower section can thus be adjusted. After adjustment the section can be locked in adjusted position by means of a screw 33 which engages the screw 33 and by means of a screw 38 which engages the latch 36 and forces it into firm engagement with the lug 34.

The upper section of the guard is ypreferably supported entirely independently of the lower section. As illustrated extensions 39 and 40 are formed respectively on the bearing brackets 11and 12. The

plates

25 and 26 are provided respectively with lugs 41 and 42 which rest on these extensions and are capable of sliding movement therealong. Each of the lugs is provided with a T-bolt 43which engages a T-slot 44 in the corresponding extension. By means of these `l"bolts the upper section Aof the guard can be secured in place after adjustment. It will be noted that by removing the nuts on the I`bolts 43 the entire upper section of the guard is loosened so that itcan be freely removed to exposev the wheel and to permit the wheel with its spindle to be taken out if necessary.

Preferably interlocking means are' pro- 45 vided for insuring the uniform movement of the two uard sections forward and ybackward. s illustrated, this interlocking means comprises projections 45 on the upper ,.pl'ates 25 and 26, these projections extending into grooves 46 in the

lower plates

20 and 21.

For convenience in moving the guard forward or backward, there are preferably profvided two handlesv47.. Each of the handles 63 is constructed in two parts formed respectively onv the upper and lower plates of the guard.

' In order that water may-,be delivered to the grinding wheel and uniformly distributed 6@ along its entire length, I provide a series of l nozzles 48 as shown"clearly in Figs. 2 and 6. It will be observed that these nozzles are provided with elongated discharge orifices and that the nozzles are placed close together so as to provide a substantially con- ,is connected with a vertical drive shaft 61 tinuous sheet of water from one end of the wheel to the other. These nozzles are connected, by means of short nipples 49, with a manifold 50 which extends the entire length of the wheel.

' If a wheel 2 is to be used which is shorter than the full length for which the machine is designed, one or more of the nozzles 48, at either or both ends, may be removed as indicated in Fig. 7.' In this case the corresponding nipples 49 are closed by means of caps 48.

The manifold 50 is supported by means of

screws

51, 51 which extend respectively through

slots

52, 52 formed in

brackets

53, 53 carried respectively by the

end plates

25 and 26 of the guard.- These slots permit the manifold with the nozzles to be moved circumferentially of the wheel. In this way the nozzles ,can be adjusted in accordance with the diameter of the work being ground. After adjustment the manifold with the nozzles can be clamped in adjusted position by'tightening the

screws

51, 51 by means of

handles

54, 54 secured to' the ends thereof. Inasmuch as the nozzles 48 are carried by vthe guard, it will be clear that they will bey moved forward or backward to accommodate wheels of different diameters when the guard is moved. lVhen ythe upper section of the guard is taken ofi' to expose the Wheel the manifold and the nozzles are carried with it. Water is supplied to the manifold 50 through two pipes 5'5 which are connected by means of

flexible hose sections

56, 56 with a supply pipe 57. Water may be supplied to the pipe 57 from any desired source, but I prefer to provide a pump which is constructed and connected as a permanent part of the machine. As illustrated, the extension 4 of the main frame which carries the motor 3 lis constructed in the form of a tank arranged to receive the water which ,is discharged from the wheel. For guiding the water into the tank the main frame is provided with edge flanges 58,` 58. 'Positioned in the tank is a pump which is preferably of the centrifugal type. The rotor 59 of the pump is positioned in a casing 60 and which carries at its upper end a belt pulley 62. A belt pulley 63 is mounted on the motor shaft 14 and albelt 64 passes overand around the two

pulleys

62 and 63 to transmit power from the frame tol the latter. Suitable idler pulleys 65, 65 are provided for guiding the belt. The discharge side of the pump is connected by means of a pipe 66 with the aforesaid supply pipe 57. By means of this construction water may be supplied under proper pressure to the manifold 50 and to the nozzles whenever the machine is in operation.

As already stated, the machine is provided with a swinging frame 8 which carries the 130 work. The frame -is rovided at its ends with two large depen ing lugs 67 and 68 which carry respectively the

aforesaid trunnions

9 and 10. rlhese trunnions are seated in suitable bearing apertures in the main frame. The swinging frame 8 is preferably of skeleton construction, having a thin front plate 68a which joins near its top with a horizontal plate 68h. A plate or apron 68 extends diagonally downward from the inner edge of the plate 68b and overlaps the front flange 58 on the main frame, as clearly shown in F ig. 5. This apron assists in preventing the escape ofwater and serves to guide it downward into the space between the flanges 58. The'table 7 is Vsupported above the plate 68b and between the table and the plate there is provided a long clear open space for a purpose which will presently appear.

The' table 7 is provided with

longitudinal ways

69 and 70 and a longitudinal '1T-slot 71.

The headstock 5 is slidably mounted on the

ways

69 and 70 and is adapted to be held in place and clamped by means of a bolt 72 entering the T-slot 71. As shown most clearly in Fig. 10, the body of the headstock carries a longitudinal bushing 73 which is fixed against relative movement.l Mounted in t-he bushing 73 is a sleeve 7 4 which carries a center 75 adapted to engage and support one end of the work. The sleeve 74 is prefl erably longitudinally slidable and is held against rotative movement by means of a pin 76 which enters a slot 77 in the bushing The wall of the body part of the headstock is provided with an aperture through which the pin 76 may be put in place or re- .moved, this aperture being normall closed by a plug 78. For a purpose which will presently appear, a spring-pressed plunger 79 is mounted in a longitudinal recess in the bushing 73 and bears against the pin 76, thus tending tohold the sleeve 74 in its rearmost position.

The headstock is provided with power operated means for rotating the work. Preferably this comprises a gear 80 rotaf tably mounted on the bushing 73. The hub of the gear is extended toward the right and is provided with an annular groove into which fits a Shoe 81 serving to hold the'gear in place. lhe hubof the gear is also extended toward the left and carries a pin 82 adapted to engage a dog B secured to the work A. The gear 80 meshes with an idler gear 83 carried by a stud 84 andthe gear 83 in turn meshes with a inion 85 mounted on a rotatable sleeve 8 6'. y referably-a plate 87 is provided for covering the several gears. 'llhe sleeve 86 is rotatable. in a suitable bearing .aperture in the body. of the headstock and is splined tov a longitudinal shaft 88. Mounted on the end of thetable 7 is a housing 89 carrying a bushi 90 having its .axis

ger 107 which enga es Lei @,eea

in alinement with the axis of the shaft 88. Rotatably mounted Within the bushing 90 is a sleeve 91 which has splined engagement with the said shaft. rlhe sleeve 91 carries at its outer end a belt pulley 92 and a. simi ar belt pulley 93 is loosely mounted on the projecting end of the bushing 90. lt will be clear that when the pulley 92 is rotated power will be transmitted through the shaft 88 and the several gears to rotate the work A by means of the dog B and `the pin 82. rlhe Splined engagement of the shaft 88 with the sleeves 86 and 91 permits the headstock to be moved longitudinally along the table without interfering with the power connec-v tion. Y

rlhe trunnion 9 is preferably extended toward the left and has rotatably mounted upon it two belt pulleys 94.- and 95 which are lasmuch as the

pulleys

94 and 95 are mounted with their axes coincident with the ivotal axis of the Swingin frame, it wlll" be clear that the transmissmn of power is not interfered with by movements of the frame.

The tailstock 6 is slidable along the

aforesaid ways

69 and 70 on the table and the tailstock can be clamped in adjusted position by means of a bolt 101 which enters the Illi-slot 71. Carried by the body of the tailstock is a sliding sleeve 102 which carries a center 103 in alinement with the oenter 75. The outer end of the sleeve 102 is recessed to receive a spring104 which normally tends to move the sleeve toward the headstock. For moving the sleeve in the opposite direction there is provided a lever 105 pivoted at 106 and rovided with a fintlie walls of an aperture in the sleeve. referably a screw 108 is aoV threaded into the sleeve and is provided with a knob 109. This screw is used for ejecting the center 103 when necea rll`he machine is primarily intende for use in grinding a large number of pieces of the same character and size and when it is to be so used the headstock and the tailstock are first adjusted to the proper distance apart. 'llhev work to be ground is first dogged and then the do ged end is placed in enga ement'with t e center 75. By meansof t e lever 105 the operator draws back the center 103 ainst the 'pressure of the spring 104i. The worh'is' then swung into alinement with the centers and the center 193l is' with the-wheel. For swinging the frameto effect feeding I provide a draw bolt or screw 110 which extends through an aperture in the front of the frame. IThis screw engages a threaded nut -111 carrying a hand wheel 112. The inner end of the screw is horizontally pivoted to a bracket 113 carried by the main frame and projecting into the space between the plate 68a and the apron 68c of 4the swinging frame. The apron serves to prevent water from reaching the pivot for the screw. Surrounding the nut 111 is a sleeve 114 which is supported by pivot studs 115 extending inward from opposite sides of the aperture in the swinging frame. Suitable means is provided for connecting the threadedv nut 111 and the hand wheel 112 with the swinging frame so that rotative movement of the wheelwill serve to move the frame forward or backward on lits pivotal axis as required. The operator, by turning the hand wheel 112, can change the position of the frame as required to move the work into or out of en agement with the grinding wheel and to fee thev work during the grinding operation. order that the amount of feed may be aecurately observed, there is provided a ring 121 which has frictional engagement with an annular flange on the hand wheel. The ring 121 carries a pointer 122 which cooperates with a scale 123 on the periphery of the wheel. The ring 121 also carries a`iinger 124 which is adapted to nengage a stop125 which projects outward from the swinging frame. In practice, the operator turns the hand wheel in the clockwise direction until the work isl brought into contact with. the wheel and is reduced to the required size. In turning, the finger 124 comes into contact with the stop 125 and thereafter the ring 121 slips on theangeof the hand ,wheel and remains stationary. When grinding is completed the wheel is turned in the counterclockwise direction to remove the work from contact with the wheel and the finished work is removed. vWhen anew piecel is put in place lto be ground theoperator again turns the hand wheel in the clockwise vdirection until the finger.. 124 again qengages the stop 125.y The engagement of the` finger with the sto constitutes .notice to the operator that the work is ground approm'- mately'to the Vrequired size. If 1t' is found that becau of wear of the'lwlieeli er for Preferably, in

some other reason' further grinding is required, this can be effected by still further turning the hand wheel, the amount of turning being measured by the graduations of the scale 123.

As already stated, the vgrinding wheel 2 extends substantially the entire length of the work or over 'thatpart of the work which is to be ground, and for this reason it is diflicult for the operator 'to remove the finished work and put a new piece in place when the work is close to the wheel. There is danger that the operator will accident-- ally engage the work with the wheel in putting it in or taking it out and thus mar it, and there is further danger that vhe will allowhis hands to contact with the wheel, thus seriously injuring himself. In order to avoid these difficulties, I have -provided means whereby the swinging frame may be moved quickly through a considerable angle to remove the axis of the centers from the wheel a distance sufficient to enable the operator to put the workl in place and remove it with entire safety.

With this end in view the connection between the nut 111 and the ,sleeve 114 preferably comprises means whereby `relative movement may be effected without turning the nut. In the preferred embodiment of the invention, I provide a cam collar 116 which is rotatably and relatively slidably mounted on the sleeve 114 and which is provided with a handle 117 by means of which it may be turned. The collar 116 at its outer end is associated with the hand wheel 112, a ball bearing 118 preferably being interpdsed. At its inner end the collar 116 is provided with two oppositely positioned similarly formed cam surfaces 119. rlhese two surfaces respectively 'engage rollers 120 carried by the aforesaidstuds 115. When the cam collar 116 is in the position shown in Figs. `5 and 8 the highest points of the cam surfaces are in engagement with the rollers, and in -this way the swinging frame is'supported in its normal operative position. By moving the handle 117 to the posltionv indicated by dotted lines in Fig. 8,-V

the rollers will be made to travel relatively downward along the cam surfaces 119, thus without interference when Pthe cam collar 116 is turned. After the inished work has been taken out and a new pieceput 1n, the handle 117 is returned 'to the posltion shown refto accurately llnnt the movementr of the by full lines in Fig.. 8thus restorin the .table lto exactly its former position. verably, as shown in Figs. 3, 8 and 9, .the cam cellar 116 carries a stop 126'which 'serves the table is moved to its outer position the' stop 125 is automatically swung upward out f of the path of the finger 124. Thls permits the hand wheel 112 to be turned indefinitely in either direction for additional movement of the swinging' frame without disturbing in any Way .the adjustment of the frictlon ring 121 and of the finger 124 carried thereby. When the collar 116 isturnedtovswing the frame forward the stop 125 maybe returned to operative position. I

Preferably, in order to partly counterbalance the weight of the swinging frame and of the parts attached thereto, I provide two links 131 which are pivoted to the swing- Aing frame at their front ends and which are engaged at their rear ends by coil springs 132. These springs serve totension thelinks andto apply to the frame a force tending to struction enables the operator to more easily swing the'frame by means of the handle 117.

Preferably the table 7 is not iiXedly connected to the swinging frame butA is adjustvably connected thereto so as to be capable of a slight pivotal movement about a pivot pin small circumferential depressions or grooves. When such depressions are present they tend to .cause corresponding ridges onthe work and thus diminish the accuracy of the iinished product. To avoid such inaccuracies T preferably provide means whereby the work may be moved a short distance longi- Tlig. 10, a transverse rotatable shaft 142 is mounted in a suitable aperture in the body of the headstock. This rock shaft is provided at its forward upper end with a hand wheel 143 and at its lower end it is provided with a cam or eccentric 144. Threaded into the outer end of the sleeve 74 is a screw 145 carrying a lock nut 146. The end of this screw is positioned adjacent the cam 144. The operator, by turning the hand wheel 143, can'turn the cam 144 and thus move the sleeve 74 toward the tailstock, overcoming the resistance of the spring plunger 79. The movement of the sleeve eEects the movement of the work in the same direction, the tailstock center 103 yielding against the action of-the spring 104 to permit such movement.

. swing it upward and rearward. This con- 133 Ashown by dotted lines in Fig.11. For

swinging the table about this pivot there is provided. a screw 134 threaded into a nut 135 which is held againstrotation and which has a tongue-and-groove engagement with a bracket 136 carried by the swinging frame.

The screw extends througha'bearing aperture inl a 'bracket 137 carried by the table .and is held against longitudinal movement with respect lto the'bracket. The screw carries a vknob at 138 for turning'it. ylBy turning the screw 134 the table can be swung slightly in either direction to properly position lthe axis of the centers in. arallelism with the,

axis of the [grinding w eel; or, if required for tapered work, to position the axis ofthe ,centers atl a slight angle t the axis ofthe 4 wheel. Preferablythe hubof the knob is provided with graduations at 139 toindi- 4cate the amount of turning ofthe screw and thus indicate the amount of adjustment of beclamped in place by means of

bolts

140 and 141. Y

` llt sometimes happens that the .surface off the wheel is notentirelyeven-,and has `,the table. After adjustmenh'the table Call s soon as movement ofthe ccam 144 permits, the work is' moved in the opposite direction under the actionfof the spring 104. lBy this means the' operator can slowly reciprocate the work longitudinally, thus entirely avoiding the possibility of ridges or irregularities thereon. 1

I provide suitable means .in the form of back-rests for supporting'the work during grinding. Preferably there are lseveral back-rests positioned at regular intervals along the work. Tn' the preferred embodiment of the invention I construct theL backrests in pairs so that two of them can be put in-place orremoved at the same time. As illustrated, particularly in Figs.` 5 and 11', I provide a body casting 147 for each lpair of rests. This body is adapted to slidably engage the upper way 69 on the table and can b e secured in place by means of a bolt 148 having an enlarged head 149 adapted to engage the lower edge of the way. The body casting 147 is provided with a central bearing bracket 15()` in which is supported a pivot pin 151 extending'v longitudinally of the machine; Mounted on the pivot pin 151 at each side of the bearing bracket 150 is a lever 152. -fllach lever .152 carries at its lower endtwo shoes 153and 154 which are ar-v ranged to engage the work at the side and at .the bottom respectively. Adjacent the rearend of `each lever 152 the body casting A147 is provided with an apertured boss 155. Fitted in the aperture'of this boss are bearing bushings 156and 157 positioned respectivelyatthe upper and lower ends. Slidabl'yextendingthrough these bushings is a rod ,158 which hasa relatively loose pivotal connection l,at lts rear upper end with the forward upper endotthe lever. 152. The

-tudinally during grinding. As shown in I rod 158 carries a collar 159 which is positioned between the bushings and a coil spring 160 surrounds the rod, abutting at` one end against the collar 159 and at the other end against the end of the bushing 156. The spring 160- tends to move the rod outward and thus tends to swing the lever 152 to press the

shoes

153 and 154 against the work. The bushing'157 is adjusted to engage the collar 159 and serve as a stop to limit the movement. The bushing 156 can be adjusted to regulate the pressure of the spring.

Fig. 2 shows several pairs of back-rests in place, these being spaced at proper intervals along the work. It will be understood that when thework varies in diameter each backrest may be adjusted to properly engage and support the work at its own particular point. This is done by adjusting the bushing 157 to provide a stop when the work is reduced to the proper size, and by adjusting the bushing 156 to provide the proper spring pressure.

In order that the finished work may be easily removed and new work put in place, itis desirable to provide means whereby the several back-rests may be 'easily and quickly withdrawn. For this purpose I mount on the table 7 a. longitudinal eccentric rock shaft 161. This shaft carries atits ends trunnions 162 which are mounted in bearings 163 carried by the table. At the end of one of the trunnions is ahandle 164 by meansfof which the rock shaft can be turned. It will be clear that when the eccentric rock shaft is in the position shown in Fig. 5 lthe several back-rests will be permitted to engage the Work. However, whe-n the handle 164 is turned through approximately 18()o the surface of the eccentric rock shaft 161 will engage the lower forward ends of all of the rods 158 and'will force them rearwardv and upward, thus removing the

shoes

153 and 154 from engagement with the work.

The surface of the grinding wheel 2 must conform to the shape of the work to be ground. For cylindrical or uniformly tapered work the wheelis preferably cylindrical throughout. straight tapered work which varies in diameter the wheel must be dressed to a contour corresponding to the contour of the work. In order that the dressing of the wheel, whether for cylindrical grinding or for contour grinding, may be easily and accurately e'ected, I provide a special wheelvdressing mechanism which constitutes a permanent part of themachine. The wheel dressing mechanism by itself is not claimed as a part of this invention, being covered by my copending application for' wheel dressing mechanism, Serial No. 247,637 filed on even date herewith. This copending application shows a construction which is in many re- For work other thanv When it is so moved the tool 167 travels along the surface of the wheel to properly dress and true it. In order that the wheel may be dressed to any desired contour the tool 167 is n ot carried directly by the slide 165 but by asecond slide 166 which is transversely movable with respect to the slide 165. I provide means whereby the slide 166 may be moved forward or backward simultaneously with the longitudinal movement to enable the tool to dress the wheel to the required contour. This means comprises a former plate or bar 168 (shown in detail in Fig. 17) which is secured in a rabbet formed at the lower front edge of the table. The front edge of the former is shaped to conform to the required contbur of the wheel and it will be understood that the former *y 168 can be removed and another formersubstituted having a different contour. The slide 166 is provided with means for engaging the former 168, this means preferably .Comprising a bracket169 projecting upward from the front end of the slide and a roller 170 carried by the bracket. 171 is provided for pressing the slide forwardA and holding the roller in engagement with the former 168. Preferably there is acover secured to the table and extending over the former and the roller to protect them and exclude dirt. As shown the aforesaid bracket 137 is formed to constitute this cover.

For moving the slide 165 longitudinally of the table. I preferably provide a longitudinal threaded shaft or screw 173 which is mounted at its ends in suitable bearings in the table. This screw extends through an aperture in the slide 165 and has threaded engagement therewith. It will be seen that when the screw is turned the slide will be moved longitudinally, carrying with it the slide 166 which is at the same time moved forward or backward under the control of the former 168. I prefer to provide power mechanism for rotating the threaded shaft or screw 173. lVhen such a power mechanism is provided a suitable housing 174y is secured to the table at the right-hand end and the shaft 173 is extended into the housing. Rota'tably mounted on the shaft within the housing are two

gears

175 and 176. Splined to the shaft between the gears is a clutch collar 177. This collar has teeth at A coil spring iio y one side adapted to engage pins carried by Rotatably mounted in the

aforesaid trunnions

9 and 10 is a shaft 183 connected at its left-hand end to the

aforesaid pulleys

94 and 95. At its right-hand 'end the shaft carries a belt pulley 184. A belt 185 passes over the

pulleys

184 and 179. By means of the mechanism described power is transmitted from the

rotatable pulleys

94 and 95 .to rotatethe two

gears

175 and 176. The

gear 176 is rotated slowly in one direction andthe gear 175 is rotated rapidly in the other direction.

F or operating the clutch collar 177 there is provided a forked lever 186 mounted on a vertical pin 187 supported in bearings in the housing 174. This lever 186 carries projections which are seated in the annular grooye of the collar and when the lever is turned the collar is moved to the right or to the left into engagement either with the gear 1.76 or with the gear 175. As shown in Fig. 14, the lever 186 carries a springpressed plunger 188 adaptedto cooperate with a notched abutment 189. When the 'plunger is seated in the notch, as illustrated, the clutch colla-r is held in its central neutral position. When the plunger engages eitherc lof which the yrod can be moved longitudinally to shift the clutch. When the clutch is engaged With the vgear 176 the screw 173 is rotated slowly in the direction to move the dressing tool from left to right across the wheel. Whenthe clutch is shifted to engage the lgear 175 the vdressing' tool is moved rapidly in the opposite direction. Preferably the rod 191 fis provided with

collars

195, 195 which are permanently secured in place and are adapted to bev engaged by the slide 166 to automatically shift the rodl and prevent the movement of the slide be ond a certain limit in either direction. referably there are also provided

collars

196, 196 which,`are adjustably secured to the shaft 191. These collars are adapted to be engaged by a latch 197 carried bythe slide 166 and adapted to be swung when desired to clear the collars 196. It will be seen that the collars 196 can be adjusted to automatically stop the tool slide in a predetermined position after movement in either direction. If for any reason further movement is desired, this can be started by lifting the latch 197 and shifting the rod 191 manually. The fixed collars 195 serve to prevent movement of the slide so,- far as to injure the machine in any Way.

As will be apparent from the foregoing description, the machine is primarily intended for the grinding of a large number of similar pieces of work. In the prelimmary adapting and adjusting of the machine for the work lto be done, it is first necessary to construct a former 168 having its effective edge shaped to conform to the required contour of the finished work.4

When such a former has been constructed it is put in place in the machine and is used for dressing the grinding wheel. Before starting/ the dressing operation the operator` preferably adjusts the two

collars

196, 196 to limit the movement of the dressing mechanism at positions at or near the edges of the wheel. Assuming that the slide 165 is in its left-hand position, the operator, by

means of the hand wheel 112, swings the frame 8 far enough to bring the tool'167 into engagement with the wheel. Then the operator, by means of the rod 191, starts the movement of the slide 165 which carries the tool 167 slowly toward the right. During this movement the position of the tool 167 is controlled by the former 168, and, because of the spring 171, the pressure of the tool against the wheel is definitely limited. After movement across the. wheel the slide is automatically sto ped by the right-hand collar 196. In initially dressing therwheel it may be necessar to move the tool across it several times. hen this is required the operator moves the hand wheel slightly to withdraw the tool from engagement with the wheel and then, by

means of the rod 191, shifts the clutch 'to means of the lever 117, swings the work support forward. The blank is first fitted with a dog and then is engaged with the headstock center 75 and the tailstock center 103 is drawn backward and afterward released remeea i@ into engagement with the end of the blank. A The several back-rests are properly positioned to engage the blank at suitable intervals along its length and each of the backrests is adjusted to apply the required spring pressure to the work. While the work support is being put in place the back-rests arc held inoperative by means of the eccentric shaft 161. Afterthe blank is properly engaged by the centers the eccentric shaft 161 is turned to permit the shoes to engage the blank.

After the blank has been thus put in place and engaged, the operator turns the lever 117 to its right-hand position and thus swings the work, support forward. Further forward movement of the work support is effected by turning the hand wheel 112 in the clockwise direction. As the hand wheel wheel the'ring 121 slips on its bearing. The

hand wheel is turned until the work is reduced to size.

During thel grinding operation the opera-A tor may, if he finds it necessary, reciprocate the work to a slight extent longitudinally by means of the handwheel 14:2. In the case of cylindrical work'this longitudinal reciprocation may take place without restriction. However,l in the case of shouldered work such as illustrated, the blank must be carefully moved in the direction to carry the shoulder of the blank away from the corresponding shoulder of the wheel.

As soon as the work has been reduced to size theoperator turns the lever 117 toward the left, thus swinging the work support for- Ward. `This forward movement of the work support carries the blank far enough away from the wheel to permit its easy removal and to permit the easy substitution of an ungroundblank.,

After an unground blank has been put in place the handle '117 is again turned toward the right, the operator first, however, having given the hand wheel 112 a part of a turn in the counter-clockwise direction. In effecting grinding-'of the second blank, the operator again turns the hand wheel in the clockwise direction until the lug 124: again engages the stop 125. This engagement constitutesl notice to the .operator that the work is ground to size or approximately to size.

As the ,Wheel wears and becomes reduced in diameter the guard may be moved backward correspondingly. When it becomes necessary to inspect the wheel this can. be readily done by removing the drop section of the guard. It will be noted that inasmuch as the nozzles 48 are mounted on the gua-rd they will be meved backward when the guard is moved backward and will also be removed when the top section of the guard is removed. 4

IWhat I claim is:

1. In a grinding machine, the combination of a mainframe, a kgrinding wheel mounted on the fra-me for rotation about a fixed axis, flanges at the edges of the main frame i0 for preventing the escape of water, an auxiliary frame pivoted to the main frame for movement about an axis parallel with the wheel axis and below the level thereof, a Work support on the auxiliary frame adapt-1 75 ed to hold a work blank in operative relai-j tion to the Wheel at approximately the level of the wheel axis, and an apron carried by the auxiliary frame and extending downward and rearward over the adjacent flange 60 on the main frame.

2. In a grinding machine, the combination of a main frame, a grinding wheel mounted on the frame for rotation about a fixed axis, an auxiliary frame pivoted to the main frame 35 for movement about an axis parallel with the wheel axis and below the level thereof, a work support on the auxiliary frame adapted to hold a work blank in operative relation to the wheel at approximately the level of the wheel axis, means for moving the auxiliary l frame about its pivot comprising a draw bolt pivoted to the main frame and extending through an aperture in the auxiliary frame, and an apron carried bythe auxiliary frame and extending downward and rearward over the pivotal connection between the main frame-andv the draw bolt. v

. 3. Ina grinding machine, the combination of a rotatable4 grinding' wheel, a work support for holding a work blank in operative relation to the wheel, feed ymechanism foreffecting aI relative approaching or separatingmovement between the wheel and the work support, and ,meansfor causing a supplemental approaching or separating movement without disturbing the adjustment of the feed mechanism.

4. In a grinding machine, the combination of a rotatable grinding wheel, a work sup- H0 port for holding a work blank in operative relation Ato the Wheel, feed mechanism forA effecting a relative approaching or separating movement between the wheel and the work support, and means operable independ- 1115 ently of the feed mechanism for causing a separating movement away from the relative positions determined by the feed mechanism and for causing an approaching movev ment exactly to the said relative positions.

5.l In a grinding machine, the combination of a grinding wheel rotatable about a fixed axis, a work support for holding a work blank in operative relation to the wheel, feed mechanism for moving the work support toward or from the wheel, and means for supplementally moving the work support toward or from the wheel without disturbing -the adjustment of the feed mechanism.

6. In a grinding machine, the combina- 13'0 tion of a grinding wheel rotatable about a fixed axis, av work support movable about avr pivotalaxis parallel with the wheel axis and adapted to hold a work blank in operative relation to the wheel, feed mechanism for moving the work support about its pivotal axis toward or from the wheel, and means for supplementally moving the work support about its pivotal axis toward ory from the wheel without disturbing the ad-v justment of the feed mechanism.

7. ln a grinding machine, the combina? tion of a grinding wheel rotatable about afixedy axis, a work support movable toward fand from the'wheel and adapted to hold a work blank in operative relation to the wheel, feel mechanism for moving the work support, and mechanism interposed between the feed mechanism and the Work support for transmitting the action of the feed mechansim, the said interposed mechanism' being4 adjustable independently of the feed mechanism to move the work support. x

9. ln a grinding machine, the combination of a grinding wheel rotatable about a fixed axis, a work support movable toward and from the wheel and adapted to hold a work blank in operative relation to the wheel, feed mechanism for moving the work support, mechanism including .a pivoted cam interposedl between the feed mechanism and the work su port-f for transmitting the action of the eed mechanism, and means for adjusting the cam independently of the feed mechanism to move the work support.

10. In a grinding machine, the combina- 'tion of a main frame, a grinding wheel mountedl on thev main frame for rotation about a fixed axis, a work support movable toward and from the wheel and vadapted to hold a work blank in operative relation to the wheel, a draw bolt connected to the main bolt for moving the work support, mecha.- nism interposed between the feed mechanism and the work support for transmitting the action of the feed mechanism, and means for moving the said interposed mechanism' `to move the work suppertrindependently of the feed mechanism.

11. In a grindingmachme, thecombinaframe, feed mechanism engaging the draw time@ tion of a mainframe, a grinding wheel mounted on' the -main frame for rotation about a fixed axis, a work support movable toward and from the wheel and adapted to hold a work blank in operative relation to the wheel, a draw bolt connected to the main frame, feedmechanism engaging the draw bolt for moving the work support, a cam mounted on the drawr bolt vbetween the feed mechanism and thel work 'support for transmitting the action of the feed mechanism, and means for turning the' caml` to move the work support independently of the feed mechanism.

12. ln a grinding machine, the combination of a"mainy frame, a grinding wheel mounted on the main frame for rotation about a fixed axis, a work support movable toward and from the wheel and adapted to hold a work blank in operative relation to the wheel, a draw bolt connected to the main frame, feed mechanism comprising a hand wheel engaging the draw bolt for moving the work support, an arm frictionally connected with the hand wheel, a stop for limiting the movement of the arm, mechanism in-` terposed between the feed mechanism `and the work support for transmitting the action of the feed mechanism, and means for movinfr the said interposed mechanism to move the work support independently of the feed mechanism and without moving the arm with respect to the hand wheel.

13. ln a grinding machine, the combination of a main frame, a grinding wheel mounted on the mainframe for rotation about a fixed axis, a Work support movable toward and from the wheel and adapted to hold a work blank in operative relation to the wheel, a drawbolt connected to the main frame, feed mechanism comprising a hand wheel engaging the draw bolt for moving the work support, an arm frictionally connected with the hand wheel, a stop normally positioned to limit the movement of the arm but movable out of the path of the arm to permit the movement thereof indefinitely in either direction, Amechanism interposed between the feed mechanism and the work sup ort for transmitting the action of the feed) mechanism, and means for moving the said interposed mechanism to move the work support independentlyof the/feed mechanism and without moving the arm with respect to the hand wheel.-

14. 'ln a grinding machine, the combination of a grinding wheel rotatable about a fixed axis, a work 'support movable toward and from the wheel and .adapted to hold a work blank in operative relation to the wheel, feed mechanism comprlsing a hand wheel for moving the work support, an arm frictionally connected with the hand wheel, a stop normally positioned to hmit the Laurence 15. In a grinding machine, the combina-.

tion of a main frame, a grinding Awheel mounted` on the main frame'for rotation about a fixed axis, a work support movable toward and from the wheel and adapted to hold a work blank in operative relation to I the wheel, a draw bolt connected to the main frame, feed mechanism comprisingf'a hand wheel engaging the draw bolt for moving the work support, an arm frictionally connected with the hand wheel, a lstop normally positioned to limit theA movement of the arm, a cam mounted on the draw bolt between the feed mechanism and the work sup ort for transmitting the action of the fee mechanism, means for turning the cam to move Y the work support independently of the feed mechanism and without movlng the arm with respect to the hand wheel, and means for moving the stop to an inoperative4 position upon the turning of the cam to move the work support away from the wheel.

16. The combination in a cylindrical grinding machine, of a work support provided with devices for holding and rotating a work blank, a rotatable grinding wheel having its axis parallel with the axis of the 'workblank and having a broad face extending the full length of the part of the blank to be ground, feed mechanism for effecting a relative approaching or separating movement between the wheel and the work support, and means for causing a supplemental approaching Ior receding movement without disturbing the adjustment' of the feed mechanism.

17. The combination in a cylindrical grinding machine, of a work support movable about a horizontalpivotal axis and provided with devices fo`r holding a work blank and rotating it about an axis parallel to the pivotal axis, a rotatable grinding wheel having its axis parallel with the aforesaid axes vand having a broad` face extending the full length of the part of the blank to be'ground, feed mechanism for moving the work support about its pivotal axis toward or from the wheel, and means `for causing a supplemental movement of the work su ,port toward 0r from the wheel without disturbing the adjustment of the feed mechanism.

18. The combination in a cylindrical grinding machine, 'of a work support provided with devices for holding and rotating a work blank, a'rotatable grinding wheel hav-- ing its axis parallel with the axis of the work blank and having a broad face extending the full length of the part of the blank to be ground, feed mechanism for efecting a relative approaching or separating movement between the wheel and the work support, and a plurality of back-rests carried by' the work support and engaging the work at intervals along its length.

19. The combination ina cylindrical grinding machine, of a work support provided by the work support and engaging the work,

some of the back-rests being bodily movable independently of others whereby their distribution along the work may be changed.

20. The combination in a cylindrical grind- 'ing machine', of a work support provided with devices for holding and rotating a work-blank, a rotatable grinding wheel having its axis parallel with the axis of the work blank and having a broad face extending the full length of the part of the blank to be ground, feed mechanism for ef-l fecting a relative approaching or separating movement between the wheel andthe work y"support, and a plurality of back-rests carried by the work support and enga ing the work at intervals along its length, t e b'aokrests being connected in pairs and each pair being bodily movable independently .of the other pairs whereby the distribution along the work lmay be changed.

21. The combination in a cylindrical grinding machine, of a work support provided with devices for holding and rotating'a work blank, a rotatable grinding wheel having its axis parallel with the axis ofthe work blank and having a broad face extending the full length f the part of the blank to be ground, feed mechanism for effecting a relatlve approaching or separating movement between length of the part of the kblank to be ground,

its length, and means for simultaneouslyv withdrawing all of the back-rests from engagement with the work.

23. The combination in a cylindrical grinding machine, of a work vsupport provided with devices for holding and rotating a )vork blank, a rotatable grinding wheel having its axis parallel with the axis of the work blank and having a broad face extending the full length of the part of the' blank to be ground, feed mechanism for effecting a relative approaching or. separating movement between the wheel and the work support, a plurality of back-rests carried by the work support `and engaging the work at intervals along itslength, and means comprising a longitudinally extending eccentric shaft for simultaneously' withdrawingall of the back-rests work. A

24. In combination, a grinding wheel rotatable about a fixed axis, a table movable toward and from the wheel and provided with longitudinal ways, a headstock anda tailstock longitudinally'adjustable along the ways on the table, mechanism carried by the headstock for rotating a work blank, a longitudinal shaft having splined engagement with the said mechanism, and driving mechanism for the, shaft mounted on the end of the table and viixed against longitudinal movement.

25. In combination in a grinding machine, a main frame, a work support rovided with devices for holding a work b ank, an auxiliary frame carrying the work support and movable with respect to the main frame about an axisV parallel, tothe; axis of the blank, power actuated means movable with the auxiliary framefor rotating the blank, a grinding wheel rotatable about a-ixed axis parallel with the axis of the work blank and having a broad face extending the full length of thepart of the blank to be ground,

feed mechanism for moving the auxiliary frame about its pivotal axis toward or from the wheel, and means whereby the blank may be longitudinally reciprocated to a slight extent during grinding independently of the auxiliary frame and without interfering with the application of power for rotative movement. l y

26. In combination in a grinding machine, a main frame, a' work support rovided -with devices for holdin a work b ank, an auxiliary frame carrying the work-support and movable with respect to the main frame about an axis parallel to the axis of the `from engagement with the.

blank, power actuated means movable with the auxiliary frame for rotating the blank, a grindlng wheel rotatable' about a fixed axis parallel with the axis of the work blank ing independently of the auxiliary frame vand without interfering with the application of power for rotative movement.

27.. In combination in a cylindrical grinding machine, a rotatable grinding wheel, a work support provided with alined centers for holding a work blank in operative rela-- tion to the wheel, means for rotating the work on the centers, feed mechanism for effectlng a relative approaching or separating movement between the wheel and the work support, and means for moving the centers longitudinally independently of other parts of the work support in order to reciprocate the blank to a slight extent during grinding.

28. In combination in afcylindrical grinding machine, a rotatable grinding wheel, a

work support provided with alined centers for holding a work blank in4 operative `relation to the wheel, means for' rotating theV Work on the centers, feed mechanism for effecting a relative approaching or separating movement between the wheel and the 4 work support, means operable during grinding for reciprocating one of the centers longitudinally to a slight extent independently of'other parts of the work support, and a spring for pressing the other center against the blank and causing it to reciprocatory movement.

29. In combination in a cylindrical grinding machine, a rotatable grinding wheel, a work support provided with alined centers for holding a work blank in operative relation to the wheel, means for 'rotating the work on the centers, feed mechanism for effecting a relative approaching or separating movement between the wheel and the work supporta spring for pressing one lof the centers against the blank, and a device partake of the operable duringl grinding for moving the other center longitudinally in one direction in opposition tothe spring independently of other parts of the vwork support, the blank and the centers being returned by the spring independently of the said device.

30. In combination in a cylindrical grind-k ing machine, a rotatable grinding wheel, a work support provided with alined centers for holdmg a work blank in operative relation to the wheel, means for rotating the work on the centers, feed mechanism for ef- Yno