US2360120A - Grinding machine - Google Patents

Description

Oct. 10, 1944. .J I. GARSIDE 2,360,120

GRINDING MACHINE Filed' Feb. 25, 1945 5 Sheets- Sheet 1 FI'GZI M Fi 3 Oct. 10, 1944. I, ARS D E 2,360,120,

GRINDING MACHINE Filed Feb. '25, 1945 5 Sheets-Sheet 2 JOHN I. GARs/nE I42 70 Maw Oct. 10, 1944.

GRINDiNG MACHINE Filed Feb. 25, 1943 5 Sheets-Sheet 3 FIELE 134 108 125d 77 52 I37 I36 52 1/ i f g 1Z3 /94 IJDHN I. GARSIDE J. LGARsm-E 7 2,360,120 v Patented Oct. 10, 1944 GRINDING MACHINE John I. Garside. West Boylston, Mass, assignor to Norton Company, Worcester, Mass., a corporation of Massachusetts Application February 25, 1943, Serial No. 477,043

1 Claim.

The invention relates to grinding machines and more particularly to a cylindrical type grinding machine adapted for successively grinding a plurality of shouldered portions on a work piece.

One object of the invention is to provide an improved hydraulically operated shoulder type grinding machine for precisely grinding a plurality of spaced shoulders on a work piece. Another object of the invention is to provide a multiple stop feeding mechanism for precisely feeding the grinding wheel for grinding a plurality of spaced shoulders of different diameters. Another object of the invention is to provide a table locating index mechanism" and an index control for the grinding wheel feeding stops to facilitate positioning the feed stops relative to the portion of the work piece to be ground. Another object of the invention is to provide a manually operable index mechanism having a' plurality of feed control stops precisely to locate said stops in an operative position for grinding predetermined shouldered portions on a work piece. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in 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 claim.

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

Fig. 1 is a front elevation of an improved grinding machine embodying this invention; 'Fig. 2 is a fragmentary piping and wiring diagram, showing the hydraulically operated system for controlling the feeding movement of the grinding wheel together with the electrically operated control mechanism therefor;

Fig. 3 is a fragmentary vertical sectional view on an enlarged scale, taken approximately on the line 3-3 of Fig. 1, showing the feed stop control lever and associated parts; Fig. 4 is a fragmentary elevation partly in section, on an enlarged scale showing the relationship between the feed stops or gauge blocks and the hydraulically operated feed mechanism;

Fig. 5 is a fragmentary front elevation on an enlarged scale, of the control lever and the feed stopand the interconnections therebetween; and

Fig. 6 is a fragmentary plan view of the parts shown in Fig. 5.

A grinding machine has been illustrated in the drawings comprising a base II) which supports a longitudinally traversable work supporting table II. The work supporting table II is arranged to slide longitudinally on a flat way i2 and a V-way (not shown) formed on the upper surface of the base Ill. The work supporting table It serves as a support for a headstock I3 I and a footstock I4 which are provided with work supporting centers I5 and I6 respectively. The work supporting centers l5 and I6 serve rotatably to support a work piece I? having a plurality of shouldered portions I'Ia, Ilb, [70, Hot, Ile, I1 and Hg, to be ground.

The base It also serves as a support for a transversely movable wheel slide 20 which rotatably supports a wheel spindle 2| in suitable bearings (not shown). A grinding wheel 22 is mounted on one end of the wheel spindle 2!. The grinding wheel 22 is preferably driven by an electric motor 23 which is mounted on the upper surface of the wheel slide 20. A driving pulley 24 is mounted on the outer end of a motor shaft 25. The driving pulley 24 is preferably a multi-V-groove pulley which is connected by multi-V belts 26 with a multiple V groove pulley 2! mounted on the right-hand end of the wheel spindle 2| (Fig. 1). The wheel slide 2! is arranged to slide transversely relative to the base It on the usual well known flat and V ways (not shown) which is a common and well known practice in the grinding art.

The work supporting table I I may be traversed longitudinally by means of a manually operable traversing mechanism comprising a manually operable traverse wheel 30 which is supported on the outer end of a shaft 3|. The inner end of the shaft 3| is provided with a gear 32 which meshes with a gear 33 mounted on a rotatable shaft 34. The shaft 34 also carries a gear 35 which meshes with a rack bar 36 depending from the underside of the work supporting table II. It will be readily apparent from the foregoing disclosure that rotation of the hand wheel 36 will be imparted through the gear mechanism just described to traverse the table II longitudi nally in either direction, the direction of movement of the table II being determined by the direction of rotation of the traverse wheel 30.

If desired, the table II may be traversed or reciprocated longitudinally by a hydraulically operated mechanism comprising a hydrauliccylinder 40 which is supported on the underside of the table II. The cylinder 48 contains a pair of spaced pistons 4| and 42-which are connected by hollow piston rods 43 and '44 respectively with hollow brackets 45 and 46 respectively which are in turn fixedly mounted on the opposite ends of the base [9.

" A reversing lever 41 is supported on the front end of a rock shaft 48 which is connected to actuate a control valve (not shown) located within the machine base It. A manually operable stop and start lever 49 is also mounted on the front of the machine base I and is arranged to actuate a stop and start valve (not shown) to stop and start the traversing or reciprocating movement of the table II. The details of this by draulic traversing or reciprocating mechanism have not been illustrated in the present case since this mechanism is substantially identical with that shown in the prior United States patent to Wallace H. Wood, No. 2,071,677, dated February 23, 1937, to which reference may be had for details of disclosure not contained herein. A pair of table reversing dogs 50 and 5| are adjustably supported by a T-slot 52 formed in the front edge of the work supporting table I I.

WheeZ feeding mechanism within a cylindrically shaped aperture formed within the base 10 of the machine. The'feed screw 56 may be rotated manually for adjusting the positionof the grinding wheel slide in setting up the machine by means of a manually operable feeding mechanism to be' hereinafter described. a

A reduced forward end portion 60 of the feed screw 56 is slidably keyed within a rotatable sleeve 6| which is fixedly connected to a shaft 62 which supports a gear 63. The gear 63 meshes with a 'gear 64 mounted On the inner end of a shaft 65 the other end of which supports a manually operable feed wheel 66. By rotation of the feed wheel 66, the feed screw 56 may be rotated in either direction to cause the grinding wheel 22 and its supporting slide 29 to move either toward or from the work piece H.

A reduced forward end portion 60 of the feed screw 56 is slidably keyed within a rotatable sleeve Bl which is fixedly connected to a shaft 62 which supports a gear 63. The gear 63 meshes with a gear-64 mounted on the inner end of a shaft 65, the other end of which supports a manually operable feed wheel 66. By rotation of the feed wheel 66, the feed screw 56 may be rotated in either direction to cause the grinding wheel 22 and its supporting slide 20 to move either toward or from the work piece IT. A stop pawl 61 is pivotally mounted on the front of the machine base I9 and is arranged in the path of a stop. abutment 68 to facilitate precisely stopping the infeeding movement of the grinding wheel 22.

In order that the wheel slide 20 may be rapidly moved toward the work supporting table II to grind a work piece I! by the plunge-cut method, the feed screw 56 is connected to a. piston rod 10. A fluid pressure cylinder II is mounted within the base ll] of the machine and contains a slidably mounted piston 12 which is grinding wheel 22,

within the base H] of the machine.

connected with or formed integral with piston rod 1|]. As illustrated in Fig. 2, the other end of the piston rod 10 is fixedly connected to the slidably mounted bearing unit 58 so'that when fluid under pressure is admitted to either end chamber of the cylinder H, the endwise movement of the piston rod 10 will be transmitted to produce an axial endwise movement of the feed'screw 55 which in turn transmits this motion to produce a transverse feeding movement of'the grinding wheel slide 2a and the rotatable A motor driven fluid pressure pump '14 is arranged to pump fluid through a pipe 15 from a reservoir 16 which islocated The pump 14 forces fluid under pressure through a pipe 11 to a feed control valve 18. The feed control valve 18 is preferably a piston type valve comprising a valve stem 19 having formed integrally therewith a plurality of valve pistons. In the position of the valve 18 (Fig. 2) fluid under pressure passing through the pipe 11 passes through a passage and a cylinder chamber 8i to move the piston 12 together with the wheel slide 20 and the grinding wheel 22 to a rearward or inopertaive position. During the passage of fluid under pressure into the cylinder chamber 8|, fluid is exhausted from a cylinder chamber 82 through a passage 83 and out through an exhaust pipe 84 into the reservoir 16.

Similarly when the valve stem 19 is shifted toward the left (Fig. 2), the direction of flow of fluid within the feed cylinder "II will be reversed. In this position of the valve, fluid under 2 pressure passing through the pipe 11 will pass through the control valve 18, through the passage 83 into the cylinder chamber 82 to initiate a movement of the piston 12 toward the left which in turn transmits a motion toward the left of the wheel slide 29 and the grinding wheel 22 to cause an approaching movement of the grinding wheel 22 toward the work piece H.

The forward end of the valve stem 19 is provided with a spool shaped member 86 which is connected by a pin 81 with a lever 88. The lever 88 is pivotally supported by a stud 89. The lower end of the lever 88 is connected by a stud 90 with link 9| with pull type electric. s'olefnoid 92. The valve stem 19 is normally held in its right hand end position (Fig. 2) by means of a tension spring 93 which is. connected, at one end with the lever 88 and is connected at the other end through a stud 95 which is fixedly mounted relative to the base l9 of.v the machine. When it is desired to cause an infeeding movement of the grinding wheel 22, the solenoid 92 is energized in a manner to be hereinafter described which serves to rock the lever 88 in a counterclockwise direction (Fig. 2) to shift the valve stem 19 toward the left to initiate an infeeding movement of the grinding wheel 22.

Dash pot work to be ground. The dash pot pistonsfl and 98 are normally held in a rearward or right hand end position by means of compression springs. During the rapid approaching movement of the grinding wheel 22, the dash pot pistons 91 and 9B are inoperative.

The piston rod 10 extends toward the rear of the machine. A sleeve 99 is adjustably supported on a piston rod 10 and is provided with apair of integrally formed diametrically opposed arms I and IOI arranged to engage the dash pot pistons 91 and 98, respectively. An adjustable stop collar I03 is adjustably mounted on a threaded portion I04 formed on the rear end of the piston rod I0. When fluid under pressure is admitted into the cylinder chamber 82 to cause the grinding wheel 22 to move toward the workpiece II, the rapid approaching movement continues until the adjustable stop collar I03 engages the end of the sleeve 99; Continued movement of the piston I2 is resisted by the dash spot pistons 91 and 98 which forces fluid under pressure from the dash pot cylinders through an adjustable needle valve I05 into a reservoir I06. By adjustment of the needle valve I05, the exhaust of fluid from the dash pot cylinders may be readily controlled to produce the desired infeeding movement, and the grinding wheel 22 will be moved into the work piece H to grind the same at the desired rate of speed. The dash pot mechanism is sub-- stantially' the same as that shown in the United States patent to R. A. Cole and C. H'. Amidon, No. 2,101,790, dated December 7, 1937, and since this feature is not considered to be a part of the present invention, the details of disclosure have not been completely illustrated and described herein. For details of disclosure not contained herein reference may be had to the above mentioned :prior patent.

Positive stop In order to grind a work piece I! to a predetermined size it is necessary to feed the grinding wheel 22 toward the work piece to grind the same and then to stop the infeeding and allow the grinding wheel 22 to grind out or to allow the sparks to die out in order to round up the work so that it will be ground to a true cylindrical surface of a predetermined size. In the present disclosure, the machine set up is provided with an adjustable stop sleeve I06 which surrounds the sleeve 99. The positive stop sleeve I06 is arranged to engage the end face of the dash pot cylinder head I08 positively to limit the infeeding movement of the Wheel slide 20 and the grinding wheel 22.

M uZti-stop I It is desirable to provide a multi-stop mechanism for limiting the infeeding movement of the wheel slide 20 so as to limit the infeeding movement of the grinding wheel 22 to facilitate successively grinding a, plurality of shouldered portions on the work piece H to predetermined sizes. This multi-stop mechanism is preferably arranged so that it may be manually actuated from the operators station in front of the machine. As illustrated in Fig. 5, a bracket H0 is fixedly mounted on the rear of the machine base and is provided with a downwardly extending portion having a bearing (not shown) which serves as a support for a rock shaft III. The rock shaft III supports a sector-shaped frame H2. The frame II2 serves as a support for a pair of arcuate shaped members H3 and H4 which form anelongated slot or aperture II5 surrounding the threaded portion I04 of the piston rod I0. The arcuate shaped members H3 and I14 are removably mounted on the frame II2 so that they may be readily interchanged ifdesiredr The arcuate shaped members H3 and H4 serve as supports for a plurality of pairs of feed stops or gauge blocks H6, 60., Ill, II'Ia, II8, II8a, II9, II9a, I20, and I20a which are arranged so that they may be successively swung into operative position between the stop collar I03 and the end of the sleeve 99. The stop blocks or gauge blocks are resiliently supported on the arcuate shaped members H3 and H4. The successive pairs of gauge blocks are interposed between the stop collar I03 and the sleeve 99 to successively stop the infeeding movement of the grinding wheel 20 to produce shouldered cylindricalportions on the work piece H of predetermined diameter.

,A manually operable mechanism is provided for shifting the frame II2 successively to position the stop or gauge blocks in operative positions, comprising a manually operable lever I25 which is pivotally mounted on the forward end of a stud or shaft I26. The rear end of the stud I26 is supported in the front cover on the base I0 of the machine..

An arm I2! is pivotally supported on the stud I26 and is formed as an integral part of the control lever I25. The lever I2! is connected by a stud I28 to the upper end of a link I29. The

lower end of the link I29 is connected by a stud I30 with one end of a lever I3I. The lever I3I is fixedly supported on the front end of the rock shaft III. It will be readily apparent from the foregoing disclosure that when the control lever I25 is rocked in either direction a movement will be imparted through the lever and link mechanism above described to rock the frame II2 so as to position the feed stops successively in operative position. I r

In order to facilitate positioning the feed stops the upper end of the lever I25 is formed as a pivotally mounted lever I25a which is supported by a stud I32 on the upper end of the lever. I25. The lever I25a is provided with adetent I33 which is arranged to engage one of a plurality of notches I34 formed in a bracket I35 which is fixedly mounted on the base I0. The notches I34 are previously numbered-so that the operator may visibly know which pair of feed stops are in operative position.

A positioning plate I36 is adjustably mounted on the front edge of the work supporting table I I and is supported by -T-bolts I31 and I38 which anchor the plate I36 relative to the T-slot 52 on the front edge of the table II. The upper surface of the plate I36 is divided into portions corresponding to the length of the shoulders or portions of the work piece H to be ground. These spaces on the plate I36 are numbered to correspond with the shoulder ofequal diameter on opposite ends of the work piece II. It will be readily apparent from the foregoing disclosure that when table II is moved longitudinally to position a predetermined shoulder on the work piece H in operative position relative to the grinding wheel 22, an index pointer I39 which is fixedly mounted on the bracket I35 will indicate by movement the portion to be ground on the scale formed on the upper surface of the plate I36. The operator may swing the lever I25a to disengage the detent I33 from the notch I34 and may then swing the lever I25 either in a clockwise or counterclockwise direction so that the detent I 33 will engage a notch I34 corresponding to the indication on, the scale formed on plate I36 so as toposition a predetermined pair'of feed stops'in anoperative position relative to the wheel feeding mechanism.

,An electrically operated control mechanism is provided for initiating and controlling the wheel feeding movement of the grinding wheel 22. A control lever I40 is pivotally mounted on a stud I II which is fixed relative to the base I of the machine. The lever I40 is arranged to actuate either one or the other of:.a pair of push button Microflex automatic instantaneous reset timer manufactured by the Eagle Signal Corporation,

Moline, Illinois. When the time relay I43 timing interval terminates, the solenoid 92 is deenergized thus releasing the tension of the spring 93 to return the control valve 18 to the position illustrated in Fig. 2. In this position of the valve 18, fluid under pressure will be initiated to cause a rearward movement of the grinding Wheel 22 'to an inoperative position.

A push button switch I44 serves as a stop switch. When this push button is actuated it serves to break the circuit thus rendering the electrical control inoperative and if actuated during operation serves to return the time relay I43 to its initial starting position and also through the solenoid 92 shifting the control valve- I8 to admit fluid under pressure to move the grinding wheel 22 to a rearward or inoperative position. The control lever I40 is arranged so that when it is rocked in a, counterclockwise direction (Fig. 2) it will actuate the push button switch I42 to start a grinding cycle. If at any time during the grinding cycle it is necessary or desirable to stop the grinding operation, the control lever I40 may be rocked in a clockwise direction to actuate the push button switch I44 and thus stop the grinding operation.

The operation of this improved shoulder grinding apparatus will be readilyv apparent from the foregoing disclosure. Assuming all of the adjustments have been previously made, a work piece I! is placed in position on the work supporting centers I and I6. The table II is then moved longitudinally to position a predetermined shoulder in operative position with relation to the grinding wheel 22. The operator then notes the index pointer I39 to determine which feed stops should be moved into an operative position. As indicated in Fig. 6, the shoulder member is opposite the grinding wheel 22, according to'the After the feed stops have been moved into an operative positionthe control lever I 40 may be shifted infa counterclockwise direction (Fig. 2) to initiate an infeeding grinding cycle. --The grinding operation continues for a predetermined time interval after which the electrical time relay I43 breaks the circuit and thus deenergizes the solenoid 92 which allows the control valve 'I8to be shifted to cause a rearward movement of the grinding wheel 22 to an inoperative position. The table II may then be traversed longitudinally in either direction to-position another portion of the work piece I! with respect to the grindingwheel 22, and the grinding of the plurality of shouldered portions may be continued until all of the shoulders have been ground to the desired predetermined size. I 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 thorovghlypractical advantages are successfully achieved. As many possible embodirnents may be made of theiabove invention and asmany changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or vshown in the accompanyingdrawings is to be interpreted as illustrative and not in a limiting sense. I claim:

In a grinding machine having a base, a longitudinally movable work supporting table, a transversely movable grinding wheel slide, a rotatable grinding'wheel thereon, means to traverse said table longitudinally, meansto feed said slide'transversely, means including a plurality of feed stops successively to limit said infeeding movement and successively grind a plurality of shoulders on a work piece, a pivotally mounted support for said feed stops, an adjustable index ar adjustably supported on said table, and a fixed index pointer on said base cooperating therewith; said index being graduated tocorrespond with the spaced portions on a work piece, a manually operable pivotally mounted control lever on the front of the base which is operatively connected to move said support successively to position said feed stops into an operative position, and means including a plurality of spaced notches for successively positioning said lever in one of a plurality of positions, said notches being visibly indexing on said bar determined feed stop to facilitate locating a prein an operative position.

JQI-IN I. GARSIDE.

indexed to correspond to the.

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