US2331089A - Grinding machine - Google Patents

Description

O 5, 194 c. G. FLYGARE ETQAL' GRINDING MACHINE 3 Sheets- Sheet 1 Filed Jan. 15, 1942 CHI-7L. Eff 1. YEHRE CZ. FIFi'ENCE REEN Oct. 5, 1943- c. G. FLYGARE ETAL GRINDING MACHINE Filed Jan. 15, 1942 5 Sheets-Sheet 5 l I I awe/whom EHRL. EFL YEP/RE 'CL FIRENCEJEREEN Mum Patented Oct. 5, 1943 UNITED STATES rarriazirr OFFICE 2,331,089 cnmnnvc monmn Carl G. Flygare and Clarence J. Green, Worcester,

Mass.. aasignors to Norton Company, Worcester, Masa, a corporation of Massachusetts Application January 15, 1942, Serial No. 426,894

3 Claims.

The invention relates to grinding machines, and more particularly to a grinding wheel spindle reciprocating mechanism.

One object of the invention is to provide a simple and thoroughly practical mechanism for reciprocating a grinding wheel spindle axially within its bearings. Another object of the invention is to providea grinding machine with a spindle reciprocating mechanism in which the grinding wheel spindle may be oscillated or reciprocated through an adjustable stroke.

Another object of the invention is to provide a wheel spindle reciprocating mechanism which is driven independently relative to the spindle rotating and driving mechanism, and which is provided with adjusting means whereby the reciprocatory stroke of the spindle may be readily varied as desired. Another object of the invention is to provide a wheel spindle rotating and reciprocating mechanism for a grinding machine, in which separate electric motors are provided independently to rotate the wheel spindle and independently to drive the wheel spindle reciprocating mechanism. 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 exemplifled in the structure to be hereinafter described, and the stroke of the application of which will be indicated in the following claims.

In the accompanying drawings in which is shown one of various possible embodiments of the mechanical features of this invention,

Fig. 1 is a, perspective view of a grinding machine wheel slide, showing the wheel spindle mounting together with the rotating and reciprocating mechanism therefor;

Fig. 2 is a plan view of the wheel slide, showing the wheel spindle and bearings, partly in cross section, together with the wheel spindle driving and reciprocating mechanisms;

Fig. 3 is a fragmentary end view, on an enlarged scale, of the grinding wheel unit, having the reciprocating mechanism removed therefrom; 1

Fig. 4 is a front elevation, on an enlarged scale, of the grinding wheel unit as shown in Fig. 3;

Fig. 5 is a fragmentary horizontal sectional view, on an enlarged scale, taken approximately on the line I ofFig. 4, showing the lever connection for reciprocation of the wheel spindle;

Fig. 6 is a fragmentary sectional view, on an enlarged scale, taken approximately on the line 1-6 of Fig. 2, showing the rock arm for producing the reciprocatory movement of the grinding wheel spindle; and

Fig. 7 is a fragmentary sectional view, on an enlarged scale, taken approximately on the line 1-1 of Fig. 2, showing the adjustably mounted crankpin for producing the 'reciprocatory movement of the grinding wheel spindle.

A grinding machine has been illustrated in the drawings, comprising a transversely movable wheel slide III which is provided with a V-way II and a flat way H. The V-way H and flatway 12 are arranged to mate with correspondingly shaped ways formed on a grinding machine base (not shown). The wheel slide in is arranged to be moved transversely by means of a wheel feeding mechanism which may be of the usual and well known nut and screw type, comprising a half nut l3 which is fixedly mounted onthe under side of the wheel slide Ill. The half nut l3 meshes with or engages a rotatable cross feed screw it. The rotation of the cross feed screw H may be controlled by a wheel feeding mechanism such as, for example, that shown in the expired U. S. patent to C. H. Norton, No. 762,838, dated June 14, 1904. This mechanism has not been illustrated in the'present application since it is not considered to be a part of the present invention. Consequently, for further details of construction, reference may be had to the abovementioned Prior patent.

A dovetailed slideway I5 is fixedly supported on the front of the wheel slide Ill and extends longitudinally. thereof substantially parallel to the axis of the work piece being ground. A grinding wheel unit It is provided with a correspondingly shaped dovetailed way H which mates with the ways IS. A clamping block i8 is fastened to the grinding wheel unit I6 by means of a plurality of screws l9 by means of which the grinding wheel unit I6 may be readily clamped in position or may be readily removed from the machine when desired. The grinding wheel unit I6 is provided with a pair of spaced alignedspindle bearings or bushings 20 and 2| (Fig. 2) which serve rotatably to support a grinding wheel spindle 22. The grinding wheel spindle 22 serves as a support for a grinding wheel 23.

In the usual camshaft grinding machine such. as used in the automotive industry, pear-shaped cams are produced in which the contour of the cam has no reentrant curves, so that it is practicable to utilize a relatively large diameter grinding wheel. In the grinding of other cams having a reentrant curve in the periphery, it is necessary to utilize a grinding wheel of relatively small diameter in order that the reentrant curve fore, desirable that the grinding wheel assembly be arranged so that it may be readily changed without undue loss of productive time on the machine. In the preferred form, the bearings and 2| are removably supported in semi-cylindrical surfaces 24 and 25 formed in the grinding wheel unit IS. The bearings 20 and 2i are held against rotation by pins 28 and 21. A pair of removable bearing caps 28 and 29 are provided for maintaining the bearings 20 and 2| in operative position. A pair of locating studs 30 and 3| are provided for locating the bearing cap 23 in a predetermined position on the wheel unit l8 so that it may be readily removed and replaced in the same identical position. A plurality of screws 32, 33, 34 and 35 are provided for clamping the bearing cap 28 in operative position.

Similarly, a pair of locating studs and 4! are provided for precisely locating the bearing cap 29 on the grinding wheel unit I6. A plurality of screws 42, 43, 44 and 45 are provided for clamping the bearing cap 29 in an operative position.

In actual practice, to minimize the shut-down time of the machine, two or more wheel spindle assemblies are provided, including wheel spindle 22, bearings 20 and 2i, together with grinding wheel 23, so that when it is necessary to replace a worn-out wheel, the bearing caps 28 and 29 may be quickly removed, the worn wheel together with its supporting spindle and bearings may be removed, and a fresh wheel and assembly placed in position, after which the bearing caps may be again locked in place. After such a wheel change, the cycle of operation of the machine may be again resumed and during the automatic cycle of operation of the machine, the operator may replace the worn-out wheel with a new wheel so that the reserve wheel assembly will be ready for the next replacement.

A driving pulley is mounted on a reduced end portion 5i oi the wheel spindle 22. A set screw 52 is provided for locking the pulley in position on the portion 5!. A driving mechanism is provided for rotating the wheel spindle 22 and the grinding wheel 23, comprising an electric motor 53 which is pivotally supported on the upper surface of the wheel slide by means of a pivot shaft 54. The motor 53 is provided with a driving pulley 55 which is drivingly connected by a belt 56 with the pulley 50 on the wheel spindle 22.

In order-to attain one of the main objects of this invention, a wheel spindle reciprocating mechanism is provided for imparting an axial reciprocatory movement to the wheel spindle during grinding. In the preferred form, an independent motor driven mechanism is provided, comprising an electric motor 60 mounted on the upper rear portion of the wheel slide ill. The motor 50 is provided with a multiple V-groove pulley 6i which is connected by a V-belt 52 with a multiple V-groove pulley 63. The pulley 63 is mounted on the rear end of a rotatable shaft 64 which is journalled in bearings 65 and 56 which are formed either integral with or fixedly mounted on the wheel slide ill. Tne forward end of 76 the shaft 64 supports a crank plate 61 which is provided with a transversely extending T'-shaped slot 88. The T-slot 68 serves as a support for the head 59 of a bolt Iii.

A sleeve 'Il surrounds the bolt ill and may be locked in adjusted position thereon. 10 together with the sleeve Ii are arranged so that they may be adjusted transversely so that the axis of the bolt and sleeve 1| may be either adjusted to coincide with the axis of the shaft 84 or may be offset relative thereto, in which 'case the sleeve 'li serves as a crankpin. A pair of lock nuts 12 are provided whereby the clamping bolt 1.0 may be locked in adjusted position. The sleeve 'll supports an anti-friction bearing 13, the outer portion of which is held within a casing 14. The casing 14 serves as one end of a. connecting rod, comprising an adjustably mounted rod 15 which is connected at its other end to a rock arm II. The rock arm 13 is pivotally supported by a stud 11. The stud TI is carried by a bracket 13 which is in turn fixedly mounted on the front face of the wheel slide i0.

The forward end of the rock arm 16 is yokeshaped, comprising a pair of spaced parallel arms 19 and 80 which support diametrically opposed studs 3i and 82. The inner ends of the studs 8| and 32 mate with transversely extending slots 83 and 34 formed in a sleeve 85 which fits on a reduced cylindrical portion 35 formed integral with the driving pulley II. The sleeve 85 is held in position on the portion 35 by a pair of lock nuts or collars 31. A rocking movement or the rock arm 18 will be imparted through the studs 3i and 82 to impart a longitudinal axial reciprocatory movement of the wheel spindle 22 within its supporting bearings 20 and 2|.

Assuming the bolt 1n and sleeve II to be offset relative to the axis of the shaft 54, then the collar or sleeve 1| serves as a crankpin. In this condition of the mechanism. when the driving motor 60 is started, a rotary motion will be imparted to the shaft 84, through the belt drive above described, to revolve the crankpin or sleeve H so as to impart a reciprocatory movement to the connecting rod I5, to the rock arm 16, and from the rock arm 16 to the wheel spindle 22. It will be readily understood that the extent of reciprocatory movement of the wheel spindle 2| may be readily varied and adjusted by adjustment of the bolt 10 within the T-slot 58. It will also be apparent that the speed of reciprocation of the wheel spindle 22 and grinding wheel 23- may also be varied as desired. The pulleys 5i and 63 may be readily interchanged for different diameter pulleys to obtain the desired rotary speed of the shaft 54 and the sleeve 1|. Or, if desired, the motor 50 may be of the variable speed type, such as is old and well known in the art, the speed of which may be readily adjusted by an electrical control mechanism, such as a rheostat.

The operation of this improved grinding wheel head will be readily apparent from the foregoing disclosure. Assuming the parts to have been previously adjusted, the electric motors 53 and 50 are set in motion to impart a. rotary and axial reciprocatory movement to the grinding wheel spindle 22 and the grinding wheel 23. When the wheel diameter has been reduced due to wear in grinding and also due to truing thereof to a minimum size which will produce an accurate contour on the cam being ground, the wheel spindle assembly may be readily changed by removing the driving belt 56, after The bolt movable wheel slide, a dovetailed slideway foed gether with its supporting bearings 20 and II and the pulley 50 together with the sleeve 85 may be readily removed from the machine and replaced by another wheel spindle 22 and associated parts, after which the bearing caps 28 and 29 may be again screwed in place and the grinding operation may then be resumed.

During the grinding operation when the machine requirespractically no attention on the part of the operator, the worn wheel 28 may be removed from' the spindle 22 and a new wheel placed thereon so that the wheel assembly is again made ready for mounting in the machine. It will be readily apparent that by providing a mechanism as'above described, the desired contour and finish may be produced on cams of any shape, such as a cam having a reentrant curve while the wheel II is rotated and reciprocated.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodi- ,ments may be made of the above invention and as many changes might be made in the embodiially during rotation thereof, and means including, an independent electric motor on said wheel slide operatively connected to drive said crankpin.

movable wheel slide, a dovetailed slideway on said slide,- a. detachable unit mounted thereon having a slideway mating with said dovetailed slideway, a pair of spaced spindle bearings in said unit, a rotatable grinding wheel spindle supported therein, a collar on said spindle, a grinding wheel mounted on said spindle, means including an electric motor on the wheel slide to rotate said grinding wheel, means including a pivotally mounted lever detachably connected with said collar which is operatively connected to reciprocate said grinding wheel spindle axially within its bearings, means including an adjustably mounted crankpln to oscillate said lever,

and an independent electric motor on said wheel slide operatively connected to revolve said crankpin so as to impart an axial reciprocatory move ment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is .to be interpreted as illustrative and not in a limiting sense..

Weclaim: Llnagrindingmachinehavinga on the front of said slide, a detachable unit having a slideway mating therewith, a rotatable,

ment to the grinding wheel and its supporting spindle.

a 3. In a grinding machinehaving a transversely movable wheel slide, a dovetailed slideway on said slide, a detachable unit having a slideway mating with said dovetailed slideway on said slide, a pair .of spaced spindle bearings on said unit and a rotatable grinding wheel spindle supported thereby, a collar on said spindle, a grinding wheel on said spindle, means to rotate said I spindle and grinding wheel, independently driven wheel spindle reciprocating mechanism includaxially movable grinding wheel on said imit,.

means including an electric motor adjustably mounted on said wheel slide to rotate said grinding wheel, means including an adiustably mounted crankpin and an oscillatable yoked member to reciprocate said wheelax- V ing an oscillatable yoke to reciprocate said spindle axially within its bearings, readily detachable'connections between said spool and said yoke, and readily detachable bearing caps to facilitate removal. of said spindle bearingstand said spindle to facilitate grinding wheel replacement.

CARL G. I'LYGARE. CLARENCE J. GREEN.

2. In a grinding machine having a transversely

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