US2237496A

US2237496A - Grinding machine

Info

Publication number: US2237496A
Application number: US336811A
Authority: US
Inventors: George T Muskovin
Original assignee: Norton Co
Current assignee: Saint Gobain Abrasives Inc
Priority date: 1940-05-23
Filing date: 1940-05-23
Publication date: 1941-04-08
Anticipated expiration: 1958-04-08

Description

P 1941. a. "m". MUSKUWW ZZWHNAQB GRINDING MACHINE Filed May 23, 1M0 2 Sheets-Sheet l 3mm EEC/H55 TMa/s/raw/v April 3, 1941- a. T. MUSKOVIN 2.237.496

GRINDING MACHINE Filed May 25, 1940 2 Sheets-Sheet 2 550F755 TML/SK UV/N li atented .lhprm d lhdl i Mdtllllllltlh George T. Mushovin, Worcester, ll/fasa, assignor to Norton @ompany, Worcester, Mass, a corporation of Massachusetts Application May 23, limit, Serial l lo. dddillll (lCll. Sl t l) 2 filaimsi The invention relates to grinding machines, and more particularly to a mechanism for pre-- cisely moving the grinding wheel spindle within its bearings for a shoulder grinding operation.

time object of the invention is to provide a simple and thoroughly practical grinding wheel spindle reciprocating mechanism for reciprocat-= ing the grinding wheel spindle axially within its bearings. Another object of the invention is to provide a wheel spindle reciprocating mechanism with a manually operable cam actuated mechanism for stopping the wheel spindle reciprocation.

another object of the invention is to provide a manually operable mechanism for precisely mor ing a grinding wheel spindle within its hearings the wheel may be precisely moved into operative 4 relation with a shoulder on the worlr piece in such a manner that the shoulder grinding operation may be accurately accomplished by visible indication. 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.

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

Fig. l is a sectional view through a grinding wheel slide, showing the grinding wheel reciprocating and positioning mechanism;

Fig. 2 is a fragmentary diagrammatic view, showing the arrangement of the grinding wheel relative to a shoulder work piece to be ground;

Fig. 3 is a fragmentary perspective view, on an enlarged scale, of the wheel spindle positioning and reciprocating mechanism together with the visible indicatin mechanism; and

Fig. 4t is a fragmentary plan view, on an enlarged scale, of a wheel slide having a portion of the cover broken away to more clearly show the wheel spindle actuating mechanism.

A portion of a grinding machine has been illustrated in the drawings, comprising a base ill which supports a transversely movable wheel slide ii. The wheel slide H is mounted on a transversely extending ll-way l2 and a flat way it formed on the base ill. The wheel slide l i serves as a support for a rotatable grinding wheel spindle it which is journalled in spaced bearings it and it which are supported by the wheel slide it.

The wheel spindle Ml supports a grinding wheel il at its left-hand end (Fig, l). A multi-grcove dliVlllg pulley it! is mounted on the right-hand end of the wheel spindle it and is arranged to be driven by multiple il -belts it from any suitable source of power, such as an electric motor (not shown) mounted on top of the wheel slide it.

a rotatable wo-rlr support has been diagrammatically illustrated in Fig. 2, comprising a head stoclr. center it and a footstoclr. center it, which serves as a rotatable support for a worlr piece ll cylindrical portion lid of the worh piece and ashoulder i l adjacent thereto are to be ground in accordance with the invention set forth herein.

The grinding wheel ll and its supporting slide it may be fed transversely toward the worlr axis to grind the cylindrical portion ft of the wort: piece while the wheel spindle Ml is reciprocated axially within its bearings, after which the wheel spindle is manually moved toward the left (Figs 1 and 2) to shift the left-hand side face of the wheel ill into grinding engagement with the shoulder lid to grind the shoulder to the required and predetermined extent.

The wheel slide it may be fed transversely by means or the well known nut and screw feed mechanism comprising a half nut it'll depending from the wheel slide l l which meshes with or engages a rotatable cross feed screw it which is in turn rotatably supported in the base ill. The details of the wheel feeding mechanism have not been illustrated in the present case since this feeding mechanism is old and well known in the art. For details of disclosure of the wheel feeding mechanism, reference may be had to the prior expired patent to C. H. Norton, No, 762,838 dated June id, 1904:, to which reference may be had for details of disclosure not contained herein.

suitable mechanism is provided for reciprocating the wheel spindle it axially within its supporting bearings it and it. This mechanism may comprise a worm at which is fixedly mounted on the wheel spindle i l. The worm 3t meshes with a gear ti which is supported at the lower end of a rotatable shaft ill. The upper end of the shaft 32 is provided with a disc-shaped head dd having a transversely extending T-slot 3t port for an adjustable pitman or crankpin 35. The pin 35 is pivotally connected to one end of a lever 36. The other end of the lever 36 is provided with a yoke-shaped portion 3? which straddles a stud 38. The stud 38 is fixedly mounted adjacent to one end of a pivotally mounted lever 39 which is pivotally supported on a stud all on the wheel slide ii. The lever 39 is preferably yoke-shaped and is provided with diametrically opposed studs 4i and 42. The studs 3i and 32 support rollers or shoes 43 and 53 which ride in a groove 45 formed adjacent to one end of the worm 39.

A yieldable connection is provided between the stud 38 carried by the lever 39 and the yoked member 37. A rod 48 is slidably mounted in a bearing surface 49 formed in an upwardly extending boss 50 which is formed integral with the lever 36. The rod 48 is provided with an enlarged head which has an aperture fitting the stud 38. The rod 48 extends toward the right from the boss 50. A compression spring 52 surrounds the rod 48 and is interposed between the boss 50 and a collar 53 which is fixedly mounted on the right-hand end of the rod 48. The compression of the spring 52 is sufficient normally to maintain the stud 38 in engagement with the end surface of a yoke-shaped member 3?, so that when the gear 3| is rotated to impart a planetary movement to the pitman 35 the lever 36 will impart an oscillatory movement to the stud 38 and lever 39 to reciprocate the wheel spindle I i axially within its bearings.

In case it is desired to stop the reciprocation of the grinding wheel H, the lever 39 may be swung in a counterclockwise direction against the compression of the spring 52 so that the stud 38 moves toward the left within the yoke 3i. The pitman 35 continues to revolve and impart an oscillating or reciprocating movement to the lever 31 but due to the fact that the end of the yoke 31 does not contact the stud 38, no oscillating movement will be imparted to the lever 39.

A manually operable device is provided for moving the lever 39 in a clockwise direction to stop the oscillation of the wheel spindle. This mechanism may comprise a manually operable lever 55 which is mounted on the upper end of a shaft 56 which is journalled in a bearing surface 51 (Fig. 1) formed in a cover plate 58 which is in turn fixedly mounted to the upper surface of the wheel slide H. A cam or eccentric 59 is fixedly mounted on the lower end of the shaft 56. The

eccentric 59 is positioned in the path of an ad justable stop screw 69 which is supported in an upwardly extending boss 6! formed integral with the lever 39. The length of the reciprocatory stroke of the spindle i4 may be varied by adjusting the position of the pin 35 on the head 33.

When it is desired to stop the wheel spindle reciprocation, the lever 55 is swung in a clockwise direction and the eccentric or cam 59 engages the stop screw GI] and swings the stop screw 69 together with the lever 39 in a counterclockwise direction so that the stud 38 is moved toward the left (Figs. 3 and 4) out of effective engagement with the end of the. yoke 37, thus moving the spindle M a slight distance toward the left and holding it stationary. During the time interval enemas latory or reciprocatory movement is imparted to the lever 36.

In the grinding ofa work piece 22 having a cylindrical portion 23 and a shoulder 24 adjacent thereto to be ground, it is desirable to provide a suitable mechanism whereby the cylindrical portion 23 may be ground to the desired and predetermined size, after which the grinding wheel when the wheel spindle i4 is held stationary, the

may be moved into engagement with the shoulder 29 to grind the same to the desired and predetermined extent.

In order to attain one of the main objects of the invention, a visible indicating device is provided whereby the shoulder grinding operation may be accurately and precisely performed. In the preferred construction, a dial indicating mechanism is operatively connected so that when it is desired to grind the shoulder 24 on the work piece 22, the manually operable lever may be utilized to produce an endwise movement of the spindle I l and grinding wheel l7 toward the left to move the grinding wheel H into grinding engagement with the shoulder 29 on the work piece 22. In order that the shoulder 23 may be ground to the desired and predetermined extent, a visible indicating mechanism is provided comprising a dial indicator or gauge 65 which is supported by a clamping block 66 on a vertically extending supporting member 67 which is in turn fixedly supported on the wheel slide Ii. The dial gauge 65 may be any of the standard and well known dial indicators having an indicating needle 68 which is operatively connected to be actuated by an actuating plunger 69. The actuating plunger 69 engages an arm I8 of a bell crank lever H which is pivotally supported on a shaft 12 which is journalled in a bearing surface 13 formed within the cover plate 58 which is fixedly attached to the wheel slide ll. The bell crank lever H has a downwardly extending arm 14 which is arranged to engage an end face 15 of the worm assembly which is fixedly mounted relative to the wheel spindle I 4 and which rotates and moves axially therewith during a grinding operation. A compression spring 16 is supported in an aperture Tl formed in the cover plate 58 (Fig. 1). The compression spring 76 bears against the downwardly extending arm 74 of the bell crank lever H and tends to rock the bell crank lever H in a counterclockwise direction so that the downwardly extending arm 14 is maintained in operative engagement with the surface l5.

It will be readily apparent from the foregoing construction that the manually operable control lever 55 is shifted in a clockwise direction (Figs. 3 and 4) to rotate the eccentric 59 in a clockwise direction, thus transmitting to the stop screw a counterclockwise movement to the arm 39 to cause an endwise axial movement of the spindle Mi toward the left. Movement of the spindle it toward the left causes the surface 15 of the worm assembly which is in engagement with the arm 14 to rock the bell crank lever H in a clockwise direction (Figs. 1 and 3), which movement, through its integral arm ill, transmits a vertical movement to the plunger 69 of the dial indicator so as to move the dial indicator needle 68, thus producing a visible indication of the extent of movement of the spindle I4 and also the grinding wheel 67. By utilizing this dial indicating mechanism above described, the grinding wheel I1 may be brought into grinding engagement with the shoulder 24 of the workpiece 22 and a predetermined amount of material ground from the shoulder so that not only the cylindrical portion it but also the shoulder 24 may be accurately ground to the desired and predetermined extent.

lit is desirable to provide a mechanism for rendering the dial indicating means inoperative except when a shoulder grinding operation is to be performed. A manually operable mechanism is provided comprising a rock shaft 80 which is journalled in suitable bearings 8| and 82 formed in a bracket 83 which is in turn fixedly mounted to the cover plate 58. A- manually operable handle t l is mounted on the forward end of the rock shaft W. A cam block 86 is mounted on the rear end of the shaft 80 and is arranged in the path of the arm 10 of the bell crank lever ll. in case it is desired to render the dial indicating means inoperative, the lever 84 is swung in a clockwise direction (Fig. 3) to rock the shaft 80 and the cam block 85 also in a clockwise direction, which movement rocks the lever l0 and bell H the wear on the engaging, surfaces between the arm lit and the surface 15.

The operation of this mechanism will be readily apparent from the foregoing disclosure. Assuming all of the adjustments to have been pre viously made, a work piece 22 is placed in position on the work supporting centers 20 and 2t. The work is started rotating and the grinding wheel it is rotated and is fed transversely toward the portion 23 to be ground. The lever 55 is preferably moved in a counterclockwise direction so that the eccentric 59 is out of engagement with the stop screw fit so that the rotary motion of the wheel spindle M is transmitted through the worm lit, the gear 39, and the pitman 35, to reciprocate the lever 36 and the lever 39 to impart an axial reciprocatory movement to the wheel spindle it during the grinding oi the cylindrical portion it on the work piece 22. After the portion it has been ground to the desired and premove the grinding wheel spindle H toward the left and also to move the grinding wheel i'l into operative grinding engagement with the shoulder 24 on the work piece 22. By visibly observing the movement of the dial indicator during the shifting movement of the control lever 55, the shoulder 24 may be ground to the desired and predetermined extent. The dial indicator 65 may be set so that when thedial indicator needle reaches zero, the shoulder has been ground to the desired and predetermined extent. If desired, however, a predetermined amount of stock may be removed from the shoulder by observing the indication of the needle 68 when the wheel ll first engages the surface 24, and then continuing the endwise movement of the spindle until a predetermined amount of stock has been removed, as indicated on the dial indicator 65.

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 embodiments may be made of the above invention and as many changes might be made in the'embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpretedas illustrative and not in a limiting sense.

I claim:

1. In a grinding machine having a transversely movable slide, a rotatable grinding wheel, a wheel spindle to support said wheel, bearings in said slide for said spindle, manually operable means to move said spindle axially within its hearings in, one direction, a pivotally mounted bell crank lever, one arm of said lever engaging a shoulder on said spindle, and a dial gauge actuated by the other arm of said lever visibly to indicate the 40 position of said spindle and grinding wheel.

, means to move said spindle axially within its bearings in one direction, a pivotally mounted determined extent, the control lever 84 is rocked in a counterclockwise direction to render the dial indicating mechanism operative and the control lever at is also rocked in a clockwise direction so that the eccentric 59 engages the stop screw 60 to rock the lever 38 in a counterclockwise direction, thus imparting an endwise movement of the spindle it toward the left (Figs. -1, 3 and 4) to bell crank lever on said slide, one arm of said lever engaging said spindle, a dial gauge actuated by the other arm of said bell crank lever visibly to indicate the position of said spindle and grinding wheel, and a manually operable device to rock said bell crank lever so that its arm is out of engagement with said spindle to render said dial gauge inoperative.

GEORGE T. MUSKOVIN.