US2460731A - Crankpin grinding apparatus - Google Patents

Description

Feb. 1, 1949. A. G. BELDEN ETAL 2,460,731

CRNKPIN GRINDING APPARATUS Filed May 21, 1947 v 5 sheets-sheet 1 /NVEN TOE,

' TTORNEY 111111949. ,1 G, BELDEN ETAL 2,460,731

CRANKP IN GRINDING APPAATUS Filed May 21, 1947 3 Sheets-Sheet 2 /N VEN raz p?. a @Laser G. Bewan Cnel. GY FLyqneE.

A. G. BEI-DEN ET AL CRANKPIN GRINDING APPARATUS Feb. 1, 1949.

3 Sheets-Sheet 3 Filed May 21, 1947 NVENTOR I 4 Lasfer Gf BELDEH Cnel. FLvqmeE Bvwwumaxm QrrolaNEv Patented Feb. 1, 1949 CRANKPIN VGrRINDINGr APPARATUS Albert G. Belden and Carl G. Flygare, Worcester, Mass., assignors to Norton Company, Worcester, Mass., a corporation of Massachusetts Application May 21, 1947, .Serial No. 749,414

6 Claims.

The invention relates to grinding machines, and

more particularly to a crankpin grinding machine. One object of the invention is to provide a simple and thoroughly practical crankpin grinding machine. Another object is to provide a crankpin grinding attachment for a standard cylindrical grinding machine. Anotherobjeot of the invention is to provide a crankshaft supporting chuck adapted for use on cylindrical grinding machine. Another object is to provide a crankshaft supporting chuck which is arranged to be drivingly supported on the hea'dstock of a cylindrical grinding machine. A further object is to provide a crankshaft supporting chuck, one end of which is yieldably supported on the headstock.

and the other end of which is supported by a steadyrest. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

One embodiment of the invention has been illustrated in the accompanying drawings, in

which like reference numerals'indicate like parts and wherein: l

Fig. 1 is a front View of a cylindrical grinding machine embodying the invention;

Fig. 2 is a vertical sectional view, on an enlarged scale, through the crankshaft supporting chuck, showing the chuck drivingly and yieldable supported on the headstock center;

Fig. Sis a right hand end elevation of the chuck; and

Fig. 4 is an end elevation of the crankshaft supporting chuck, showing the steadyrest support for the end portion of the chuck.

Ar cylindrical grinding machine is illustrated in the drawings comprising a base HJ which serves as va lsupport for a longitudinally reciprocable work table II. The table II supports a headstock I2. A `rotatable grinding wheel I5 is mounted on the left hand end of a wheel spindle i6. :The spindle is rotatably journalled in bearings (not shown) in a transversely movable wheel slide il. A grinding wheel driving mechanism is provided comprising an electric motor i8 mounted on the upper surface of the wheel slide I6. The motor I8 is provided with a driving pulley is which is connected by means of a belt 20 with a pulley 2l on the right hand end of the spindle I6.

The grinding wheel l5 and slide Il may be fedtransyersely relative -to the base I0 by means. of

with a gear 3l.

a feeding mechanism including a manually operable feed wheel 22. The feed wheel 22 is connected to rotate a gear 23 which is mounted en the forward end of a fed screw shaft 24. The shaft 24 serves to rotate a feed screw (not shown) which meshes with a half nut (not shown) de` pending from the underside of the wheel slide II. It will be readily apparent from the foregoing disclosure that a manualrotation of the feed wheel 22 will impart a transverse movement to the wheel slide I'I and the grinding wheel I5. The grinding wheel I 5 may be fed automatically by means of a pawl 25 which is `arranged to engage teeth on the periphery of the feed wheel 22. A hydraulically operated actuating motor contained in the case 26 which is controlled by a table reversing lever 21 is provided to actuate thepawl 25 automatically during reversal of the table II at the ends of its reciprocatory stroke.

This mechanism has not been shown in detail since it is not considered to be a part of the present invention. This mechanism is substantially identical to that shown in the prior United States Patent No. 2,071,677 to W. H. Wood dated February 23, 1937 to which reference may be had for details of disclosure not contained herein.

Almanually operable table traverse mechanism is provided to facilitate positioning the table relative to the grinding wheel I5. This mechanism may comprise a manually operable traverse `wheel 28 which is mounted on the outer end of a shaft 29. The shaft 29 supports a gear 30 which meshes The gear 3I is mounted on a rotatable shaft (not shown) which also supports a gear 32. The gear 32 meshes with a rack bar 33 which is iixedly mounted on the underside of the table I I. foregoing disclosure that a rotary motion of the manually operable traverse wheel 28 is imparted to cause a longitudinal traversing movement of A reversing and control valve unit is provided L which is connected with pipes 4I and l2v with the brackets 3l and 39 respectively toconvey fluid.`

It will be readily apparent from theV or driving plate 45. h l y n In order to attain the main object of the invenunder pressure to and from opposite ends of the cylinder 35. The table actuated reversing lever A 21 serves to actuate the reversing valve. A start and stop lever 43 is provided to actuate a startstop and speed control valve contained in the valve unit 48. This hydraulic table reciprocating mechansiniis identical with that disclosed in the prior U. S.Patent to Wood No. 2,071,677 to which `reference may be had for details of disclosure not contained herein.

The headstock I2 is provided lWith-the usual Work supporting center 46 and a rotatable face bushing 48 which mates With the headstock .cen-

ter 46. n

The face or driving plate 45 supports a pair of diametrically opposed drivingstuds or bolts 49 and`59.- The bolts 49`and 59 are provided With integral'heads 5l and- 52` respectivelywhich are supported in aV diametrically opposed radiallyextending'T- shaped slots 53 and 54 respectively Y formed in the faceplate 45." Locking nuts 55 and 56 are provided 'to lock the bolts 49 and 56 respectivelyV in adjusted positions relative to the platev 45.f A The driving bolts 49 and 58 pass through- clearance holes 51 and 58 respectively formed ina flange I59 which is an integral part of the chuck 4'1. A pair of compression springs 60 and 6I surround the'bolts 49 and 59 respectively'Y and are interposed between the flange 59 and nuts 52 and`63. The springsv andl serve yieldably to support and maintain the chuck 41 with thecenter bushing 48 in engagement with the headstock center 46.

`The main body portion of the chuck 41 is formed with atrue cylindrical peripheral surface, the right hand end of which is support'for` rotation by means of a steadyrest 65.l The steadyrest-65 is adjustably clamped onthe Work table'lll and is providedV With'a pair of adjustablymountedrsteadyrest shoes 66 and 61 which engage and support the periphery of the chuck 41. The lshoes 56 and 51 may be adjusted by means of then usual kadjusting screws-68 and 69 respectively. A bracket 18 is either formed integralwith or fixedly mounted onthe steadyrest 65.. The bracket 18 servesfas a support fora shoeY 1I which engages the upper portion of the chuck 41, thus forming a three point support for the right `hand end of the chuck 41. An adjusting `screw 12 is provided to facilitate adjustment of the shoe'1l'relativeto the bracketl. The chuck 41 is provided With'a longitudinally extending cylindrical aperture 15, the axis 'of Whichis parallel to the axis of rotation of the chuck.' VvThe axis of the aperture 15 is spaced from the axis of rotation ofthe chuck 41 by a distance equal. to the throw of the crankpin to belground. A split bushing 1611s mounted in the right hand end of the aperturel Y15. The bushing 16 is provided With a central 'aperture 11 Which The chuck 41 is arranged to support a.

Vthe bushings 8| and 82 towards each other to clamping screw 80 which passes through a vclearance hole in a bushing 8l and is screw threaded into a bushing 82. The bushings 8l and 82 are supported in atransversely extending hole 83 formed in the chuck 41 (Fig. 3). The bushings 8l and 82 are-provided Withsurfaces 84 and 85 which engage and mate with thev outer peripheral surface of the split bushing 16. It will be readily apparent from the foregoing disclosure that tightening the clamping screw 88 will draw clamp the split bushing 16 and the crankshaft 18 tobe ground in -the chuck 41. Before clamping the crankshaft 18 is rotarily adjusted so that the axis of acrankpin 19 to be ground is aligned With the axis of rotation of the chuck 41.

- In 'order to steady the crankshaft 18 during a grinding operation, a slidably mounted center 85 is provided Which engages a center hole 84 formed in the end of the crankshaftg'l. The

center 85 is formed integral with a lslidablyv mounted member 86A which slides Within the aperture 15. Av compression spring 81 which is interposed between the member 86 and an end cap 89 serves yieldably to maintain the center 85 in engagement With the center hole 84. -v

The operation of the improved crankpin grinding attachment will be readily apparent from the foregoing disclosure. The crankshaft supporting chuck 41 is mounted as illustrated in'Fig. 2 with the center bushing yieldably Vvmaintained in engagement with the-center 45. The other endv ofthe-`chuck is supported and steadied by the shoes 66, 61 and'1l of the steadyrest 65. The chuck 41 is driven by the face plate 45'by means ofthe driving studs or bolts 49 and 50. rvA crankshaft 18 to be ground is inserted Within' the split bushing 16 and moved axially until the center hole 84 engages the center 85 and Vmoves the supporting member 86 tow-ard the left (Fig. 2) to compress the spring 81. The crankshaft 18is then rotated Within the split bushing 16 until the crank arm90 (Fig. 2) engages a locating stop 9| (Fig. 3) to position the crankpin 19 to be ground in axial alignment with the axis of rotation of the chuck 41. lThe clamping screw 88 is then tightened to clamp the crankshaft `18 in the chuck 41k for a grinding operation.

The work table l l may then be traversed longitudinally to position the crankpin 19 opposite thergrinding wheel I5. The chuck 41 may then be rotated and the grinding Wheel lil-fed toward the crankpin 19 to grind it to thedesired and predetermined size. v

It will thus be* seen that there has been provided by this invention apparatus in which the I various objects hereinabove set forth together with many thoroughly practical advantages are successfully f achieved. As Inany possible em bodiments may be made yof the above invention longitudinally movable Work table, a headstock on said table having a rotatable face plate and a center, and a crankshaft supporting chuck,

yieldable means drivingly to hold one end of said `crankshaft with its axis offset from the axis of rotation by a distance equal to the throw of the crankpin to be ground.

2. In a cylindrical grinding machine having a longitudinally movable Work table, a headstock on said table having a rotatable face plate and a center, and a crankshaft supporting chuck, yieldable means drivingly to hold one end of said chuck on said center, a steadyrest on said table rotatably to support the other end of said chuck, and an offset crankshaft supporting and clamping means on said chuck to support a crankshaft so that the axis of the crankpin to be ground is in alignment With the axis of rotation of the chuck.

3. In a cylindrical grinding machine having a longitudinally movable table, a headstock on said table having a rotatable face plate and a center, and a crankshaft supporting chuck, yieldable means drivingly to hold one end of said chuck on said center, and a steadyrest on said table rotatably to support the other end of said chuck, said chuck having a split bushing to support a crankshaft with the crankpin to be ground in axial alignment with the axis lof rotation of said chuck and a binder screw on said chuck to clamp said bushing and crankshaft in said chuck for a grinding operation.

4. In a cylindrical grinding machine having a transversely movable rotatable grinding wheel, a longitudinally movable work table, a headstock having a rotatable face plate and a center which is supported on said table, and a crankshaft supporting attachment including a frame, a center hole in one end of said frame adapted to mate with the headstock center, yieldable means drivingly to hold said frame on said center, a steadyrest to support the other end of said frame, and a crankshaft supporting chuck formed in said frame.

5. In a cylindrical grinding machine having a transversely movable rotatable grinding wheel, a longitudinally movable work table, a headstock having a rotatable face plate and a center which is supported on said table, and a crankshaft supporting attachment including a cylindrically shaped frame, a center hole in one end of said frame adapted to mate with the headstock center, yieldable means drivingly to hold said frame on g said center, a steadyrest having adjustable shoes to support the other end of said frame and a crankshaft supporting chuck formed in said cylindrical frame, the axis of said chuck being offset from the axis of rotation of said frame by a distance equal to the throw of the crankpin to be ground.

6. In a grinding machine having a transversely movable rotatable grinding Wheel, a longitudinally movable work table, a headstock having a rotatable face plate and center on said table, a crankshaft supporting attachment including a cylindrically shaped frame, yieldable means drivingly to support one end of said attachment lframe on said center, a steadyrest on said table having adjustable shoes to support the other end of said frame, an aperture in said frame parallel to the axis of the frame and spaced from said axis by a distance equal to the throw of the crank-pin to be ground, a spring pressed center in one end of said aperture to engage and support one end of a crankshaft to be ground, and a crankshaft supporting chuck in said aperture adjacent to the end of said frame to support a l. crankshaft with the axis of the crankpin to be ground aligned with the axis of rotation of the frame.

ALBERT G. BELDEN. CARL G. FLYGARE.

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

UNITED STATES PATENTS Number Name Date 945,979 Norton et al. Jan. 11, 1910 1,079,494 Jantsch Nov. 25, 1913

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