US2851828A - Centerless grinder - Google Patents

Description

Sept. 16, 1958 A. w. TODD ETAL 2,851,828

CENTERLESS GRINDER Filed Nov. 28, 1956 s Sheets-Sheet 1 x I [if uvvsurons AL EXANDEI? w r000 w RICHARD M. ANDERSON I RUSSELL L. FL EM/NG ATTORNEYS Sept. 16, 1958 3 Sheets-Sheet 2 Filed Nov. 28, 1956 INVENTORS ALEXANDER W TODD RICHARD MANDERSON 6 m M M m LaT A u? M UM Sept. 16, 1958 A. w. TODD ETAL 2,851,828

CENTERLESS GRINDER Filed Nov. 28, 1956 s Sheets-Sheet :5

IN VE N TORS ALEXANDER W TODD RICHARD MANDE'RSON RUSSELL L. FLEMING A TTORNEVS United States Patent CENTERLESS GRINDER Alexander W. Todd, Springfield, and Richard M. Anderson, East Longmeadow, Mass., and Russell L. Fleming, Crescent Lake, Comm, assignors, by mesne assignments, to Van Norman Industries, Inc., Springfield, Mass., a corporation of Massachusetts Application November 28, 1956, Serial No. 624,918

4 Claims. (Cl. 51-403) This invention relates to a centerless grinder and,

more particularly, to an improved regulating wheel asv the attached drawings showing a presently preferred em- 7 bodiment of the invention and in which drawings Fig. 1 is a front view of a centerless grinder constructed in accordance with this invention;

Fig.2 is an enlarged horizontal sectional view through the regulating wheel assembly taken as indicated by the line 2-2 of Fig. 1; and

Fig. 3 is a further enlarged vertical sectional view of the regulating wheel assembly taken as indicated by the line 3-3 of Fig. 1.

As will be readily understood from Fig. 1, a centerless grinder incorporating the features of the present invention is similar in many respects to conventional centerless grinders. That is, the grinder includes a conventional bed 10 upon which a grinding wheel assembly 12 and regulating wheel assembly 14 are mounted. The grinding wheel-assembly 12 includes an abrasive wheel 16 mounted on a spindle which is rotatably supported in a housing (not, shown) and covered by a guard 18. The entire grinding wheel assembly 12 is quite conventional and only so much of it is shown as is necessary to describe the relationship of the grinding wheel 16 to the regulating wheel assembly 14, and it is deemed unnecessary to show or to describe the grinding wheel drive structure, the wheel dressing apparatus or the coolant system for the grinding wheel.

In accordance with conventional practice, the grinding wheel assembly 12 is fixedly or adjustably mounted on the bed 10 so that the grinding wheel 16 is disposed in generally opposed relationship to a regulating or control wheel 20 forming a part of the regulating wheel assembly 14, and in further accord with conventional practice, a work rest 22 is adjustably mounted on the bed 10 between the said grinding and regulating wheels. A worksupporting blade 14 is secured to the work rest to support the work (not shown) for engagement by the grinding wheel and the regulating wheel. The work rest can be moved on the bed independently of or with the regulating wheel assembly which will now be described.

The regulating wheel assembly 14 includes a wheel housing 26 which is adjustably supported on a main housing 28, the main housing being slidably mounted on the bed 10. The upper portion of the main housing 28 may be considered a gear box wherein the gears and other motion transmitting means of the regulating wheel drive 2,851,828 Patented Sept. 16, 1958 ent invention is involved principally in the construction and arrangement of the wheel housing 26, the upper portion of the main housing 28 and the elements of the regulating Wheel drive. Therefore, the lower portion of the main housing and the elements for advancing and retracting the regulating wheel, all of which are conventional, need be described only generally.

As will be observed from Fig. 1 of the drawings, the lower or slide portion of the main housing 28 is movable laterally of the machine on ways 30 at the top of the bed 10 whereby to advance the regulating wheel 20 toward the grinding wheel 16 or to retract it therefrom. The work rest 22 is movable on the same ways and a rod 32 secured to the said work rest extends into the slide portion of 'the main housing 28 for selective connection with the main housing. The means for selectively connecting the rod 32 with the main housing 28 comprises an elongated binder screw 34 (Fig. 3) which is supported in the main housing and can be advanced to bind the lating wheel assembly and when rotated in the opposite Obviously, the said sleeves can be rotated manually or by power operated direction .will retract the same.

means. In the drawings, a hand operated lever 42 is shown as the means for rotating the sleeves to advance and retract the regulating wheel assembly in grinding operations. A handle 44 is secured to the lever 42 and extends laterally toward the grinding wheel for the convenience of an operator standing at the front of the machine. When the lever 42 is rotated forwardly and downwardly from the position shown to engage a stop 46, the said sleeves are rotated to advance the regulating wheel 20 a predetermined distance toward the grinding wheel 16 and, in so doing, a workpiece supported on the blade 24 is ground to a selected diameter. The advanced position of the regulating wheel is indicated by the broken line in Fig. 1. Then, when the lever 42 is returned to the position shown, the regulating wheel assembly is retracted, returning the regulating wheel 20 to the full line position.

In order that advance and retraction of the regulating wheel by the said predetermined distance will effect the grinding of a workpiece to a selected diameter, it is necessary that the advanced position of the regulating wheel assembly be accurately fixed. It is also necessary that the said advanced position be accurately relocated from time to time to compensate for wear and dressing of the grinding wheel 16 and the regulating wheel 20. The means for adjusting and locating the advanced position of the regulating wheel and its assembly also comprises a threaded sleeve or nut (not shown) which engages the lead screw shaft 38 and is manually operated by a hand wheel 48 at the front of the main housing 28.

The main housing also includes a reservoir for the lubricant used in the regulating wheel assembly. The

reservoir itself is not shown, but there are two sight' windows 50, 50 provided at the front of the main housing for checking the lubricant level in the reservoir, and a lubricant pump 52 operated by a handle 54 is provided for circulating the lubricant through a plurality of contduits 56, 56. (The pump 52 and oil lines 56, 56 are shown in Fig. 3).

As thus far. described, the, centerless grinder is construct'ed in accordance with known practice. The operation' of the machine is also conventional. That is, a control panel 58 is provided at the front of the machine and contains the usual switch buttons 60, 60 for starting and the thru-feed method, it may be desirable to tilt the regu lating wheel spindle. The centerless grinder of this invention is particularly adapted to make regulating wheel tilting a more precise but easy task, such adaptation involving an improved regulating wheel support and drive arrangement which will now be described.

The regulating wheel drive motor 62 is arranged on top of the main housing 28 so that its shaft projects into a speed control unit indicated generally at 64. It is believed to be unnecessary to describe the unit 64 (since it is conventional) beyond saying that it is adapted to vary andthuscontrol the speed of an output shaft (not shown) within a relatively wide range by manipulation of a hand wheel 66. In this installation, the output shaft mounts a pulley for a belt drive to the regulating wheel,. and the hand wheel 66 is turned to select a regulating wheel speed indicated at a tachometer 68 on the front of the main housing. 28.

Turning now to Fig. 2', it will be observed that the drive belt 70 extends from the speed control unit 64 downwardly into the main housing 28 to a pulley 72 which is keyed to one (74) of a plurality of shafts rotatably supported and sealed in the main housing as by the anti-friction bearing units 76, 76 and the seals 78, 78. The pulley shaft 74- extends from the right-hand end of the main housing longitudinally thereof, terminating in a splined end 80. A; pinion 82 is secured to the splined end of the pulley shaft 74 and engages a compound gear 84 and the pinionv 82 hasan exposed end face 86 engageable with an axially movable clutch 88 as will be described.

The compound gear 84 is rotatably supported on a bearing stud 90 which is secured within the main housing 28 parallel to the pulley shaft 74, and the compound gear hasa large diameter gear 92 at one end and a pinion 94 at the other end. The pinion end 94 is engaged with a gear 96 which is rotatably supported on a driven shaft 98. The gear 96 has an exposed face 100- which is engageable with the clutch 88 which is splined to but movable along the driven shaft 98. It willbe observed that th'edrivensha'ft 98 and pulley shaft 74 are aligned on a laterally extending substantially horizontal axis and:the

bearing stud 90 is parallel therewith. The faces 86 and 100 of" the pinion 82 and the gear 96, respectively, are provided with clutch teeth which are engageable respectively with'similar teeth on the opposite ends of the clutch 88.

The aforesaid arrangement of the pinions and gears 82, 84' and 96 and the arrangement of the clutch 88 provides variable speed motion transmitting means between the drive motor 62 and-the driven shaft 98. That is, the aforesaid arrangement provides for a high and low speed range selection while the speed control unit 64 provides means for selecting a more specific speed within either range. More specifically, when the clutch 88 is shifted tothe right to engage the pinion 82 on the pulley shaft 75, it provides a direct driving connection between the pulley shaft and the driven shaft 98 whereby the driven.

shaft is rotated at the speed of the pulley shaft. When theclutch is shifted to the left to engage the gear. 96 on the driven shaft 98, the connection between the pulley" shaft and the driven-shaft is indirect,- through the compound gear 84 and the gear 96 which rotates at a speed substantially less than the speed of the pulley shaft.

Any clutch-shifting means may be provided which can conveniently be operated. One such means may comprise a forwardly and rearwardly movable rack supported in the main housing 28 and operated by a handle 102 at the front thereof, the rack engaging a pinion (not shown) secured to a generally vertical shaft having means attached thereto and engaging the clutch 88 to shift the same axially responsive to rotation of the said pinion and shaft.

The end of the driven shaft 98 opposite the pulley shaft is rotatably supported on an anti-friction bearing unit 76 in a bearing drum104 and secures a bevel pinion106 for rotating a spindle drive shaft 108 as will be described. The bearing drum 104 is provided in accordance with the present invention to be rotatably supported in a suitable opening in. the end of the main housing 28 which faces the grinding wheel 16. The axis of rotation of-the. bear. ing drum is the lateral substantial horizontal axis of'the driven shaft 98.

In additionto'the driven shaft 98, the bearing drum104 rotatably supports the aforesaid spindle drive shaft 108 on anti-friction bearing units 76, 76, the drive shaft projec'tin'g, rearwardly of the main housing 28 through an opening 110 which accommodates angular movements of the said drive shaft'in a vertical plane. A sleeve 112 is splined to'the inner end of the spindle drive shaft 108 and a bevel gear 114 is keyed to the sleeve in engagement with the pinion 106 on the motor-driven shaft- 98. The spindle'drive shaft 108 is connected (as will be described), by motion transmittingmeans to a spindle supporting, the

regulating wheel whereby the regulating wheel is rotated by the spindle drive shaft. Thus, the speed of rotation of the regulating wheel is directly related to the speed of rotation of the drive shaft 108. Accordingly, a flex ible shaft 116 can be connected between the tachometer 68 and the-spindle drive shaft 108 as best shown in Fig.

3 and-thetachometer 68 calibrated to indicate regulating.

wheel speed although connected to the spindle drive shaft.

The bearing drum 104, in addition to rotatably supporting the. driven shaft 98 and spindle shaft 108', also provides meanswhereby the regulating wheel'spindle and the drive'shaft can be adjusted-angularly with the regu-' lating wheel frame or housing 26 without disturbing the drive connection to the regulating wheel and the selected speed thereof. That is, the bearing drum 104' is pref era'bly connected to the regulating wheel frame 26 as' by' screws (not shown) and thus it is arranged to rotate with the said regulating wheel frame which is pivotally adjustably secured to the main housing on the end thereof which faces the grinding wheel 16.

More specifically, the regulating wheel frame 26- is detachably and adjustably secured to the main housing 28 by means of a plurality of bolts 118, 118 supported in the aforesaid end of the main housing 28 and tightened therein by a plurality of nuts 120, 120. The head ends of the bolts 118, 118 are disposed in arcuate slots 122, 122 in the regulating wheel frame and secure the said frame in adjusted position when the nuts 120, are tightened. The adjustment of the frame 26 relative to the main housing 28 is pivotal and about the laterally extending substantially horizontal axis upon which the bearing drum 104 and the driven shaft 98 rotate.

1 The regulating wheel frame or housing has a rearwardly extending portion 124 which rotatably supports the projecting rear end of the spindle drive shaft 108 on' a suitable antifriction bearing. The projectingrear por tion124-of the regulating wheel frame also supports a housing1'26 for thespindle 128 upon which the regulating wheel 20 is secured. lating wheel spindle 128 projects rearwardly similarly to the spindle drive shaft 108 and that the projectingrear' ends of the spindle and its drive shaft are connected: by.

It will be observed that the regu-- asensss motion transmitting means 130 which preferably comprises a pair of pulleys and a timing belt.

It will be obvious that since the spindle drive shaft 108 is supported by the regulating wheel frame 26 and by the bearing drum 104 and since the said frame and regulating wheel can be pivoted about the same axis, pivotal adjustment of the regulating wheel frame relative to the main housing will cause similar rotative movement of the drum relative to the main housing. Also, such pivotal or swivel movement of the regulating wheel frame 26 and the drum 104 will cause similar adjustment of the angular disposition of the regulating wheel spindle 128 and the spindle drive shaft 108 in parallel substantially vertical planes.

In further accord with the present invention, means are provided for precisely adjusting the swivel or pivoted position of the regulating wheel frame 26 and the accompanying elements. Such means comprise an elongated screw 132 supported in the main housing with its head end projecting forwardly therefrom. The screw can be arranged to directly engage the frame 26, but in the preferred construction, it engages a post 134 which is secured to the frame and extends laterally into the main housing. The main housing is provided with a suitable opening 136 to accommodate the post and limited movement thereof with the frame. It will be seen that by setting the screw 132 relative to the main housing 28 the pivoted position of the frame 26 and the associated elements can be easily located and fixed. When the screw is advanced into the main housing in engagement with the post 134, it pivots the frame so that the rearwardly extending portion 124 thereof is elevated about the aforesaid laterally extending substantially horizontal axis, When the screw 132 is retracted relative to the main housing, the weight of the overhanging rearwardly extending portion 124 of the frame and the weight of the rearwardly extending portions of the spindle and spindle housing and the spindle drive shaft and the weight of the motion transmitting means and any guard therefor tends to pivot the frame so that the post 134 will engage the end of the screw 132. Therefore, it will be readily understood that adjustment of the pivoted position of the frame and the pivoted position of the regulating wheel spindle can easily be effected merely by loosening the nuts 120, 120 on the securing bolts 118, 118 and by turning the adjusting screw 132.

Additional adjustment of the regulating wheel 20 is provided in accordance with the present invention, this additional adjustment being axially of the regulating wheel spindle. That is, a spindle housing 126 has a rack 138 secured thereto which is engaged by a pinion 140 which is secured to a shaft 142, the said shaft being rotatably supported in the frame 26 in a substantially vertical position. The shaft 142 projects above the frame 26 so that it can be manually turned to adjust the spindle housing and the spindle 128 forwardly and rearwardly along its axis. Movement of the spindle housing is accommodated on ways 144 as shown in Fig. 1.

From the foregoing description, it will be understood that the regulating wheel assembly for a centerless grinder provided in accordance with the present invention features a regulating wheel support frame or housing which can easily and accurately be pivoted relative to the main housing of the assembly whereby to adjust the angular disposition of the regulating wheel spindle without in any way disturbing the drive connection to the spindle or the selected speed of operation thereof. Thus, the regulating wheel spindle can easily be pivoted as desired for thru-feed operation or for any other operation of the grinder. In addition to the foregoing, the regulating wheel assembly provides for adjustment forwardly and rearwardly of the regulating wheel spindle and the regulating wheel as desired for various modes of operation.

While the invention has been described with specific reference to the drawings showing a presently preferred embodiment, it will be understood that the drawings and description are not to be construed as limiting or defining the invention, the following claims being relied upon for that purpose.

The invention claimed is:

1. A regulating wheel assembly for a centerless grinder and comprising a main housing which is movable laterally in the grinding operation, a drive motor rigidly secured to the main housing, a bearing drum supported in said main housing for pivotal movement on a lateral substantially horizontal axis, a shaft driven by said motor and rotatably supported in the main housing on said axis and projecting into said bearing drum, a spindle drive shaft rotatably supported in said bearing drum for pivotal movement therewith and projecting rearwardly of the drum and the main housing, motion transmitting means interconnecting the motor driven shaft and the spindle drive shaft to effect a driving connection therebetween in any pivoted position of the drum, a frame secured to the main housing for pivotal adjustment on said axis and rotatably supporting the rearwardly projecting end portion of the spindle drive shaft, a regulating wheel spindle rotatably supported by said frame, and motion transmitting means interconnecting said spindle and the spindle drive shaft, the pivotal adjustment of the frame being effective to adjust the spindle, the spindle drive shaft and the bearing drum about said axis.

2. A regulating wheel assembly for a centerless grinder and comprising a main housing which is movable laterally in the grinding operation, a drive motor rigidly secured to the main housing, a bearing drum supported in said main housing for pivotal movement on a lateral substantially horizontal axis, a shaft driven by said motor and rotatably supported in the main housing on said axis and projecting into said bearing drum, a spindle drive shaft rotatably supported in said bearing drum for pivotal movement therewith and projecting rearwardly of the drum and the main housing, motion transmitting means interconnecting the motor driven shaft and the spindle drive shaft to effect a driving connection therebetween in any pivoted position of the drum, a frame secured to the main housing for pivotal adjustment on said axis and rotatably supporting the rearwardly project ing end portion of the spindle drive shaft, a regulating wheel spindle rotatably supported by said frame, motion transmitting means interconnecting said spindle and the spindle drive shaft, and a manually operable adjusting screw threaded in said main housing and projecting rearwardly therein into engagement with said frame below said axis whereby to adjust the pivoted position of the frame and similarly to adjust the pivoted position of the spindle, the spindle drive shaft and the bearing drum.

3. A regulating wheel assembly for a centerless grinder and comprising a main housing which is movable laterally in the grinding operation, a drive motor rigidly secured to the main housing, a bearing drum supported in said main housing for pivotal movement on a lateral substantially horizontal axis, a shaft driven by said motor and rotatably supported in the main housing on said axis and projecting into said bearing drum, a spindle drive shaft rotatably supported in said bearing drum for pivotal movement therewith and projecting rearwardly of the drum and the main housing, motion transmitting means interconnecting the motor driven shaft and the spindle drive shaft to effect a driving connection therebetween in any pivoted position of the drum, a frame secured to the main housing for pivotal adjustment on said axis and rotatably supporting the rearwardly projecting end portion of the spindle drive shaft, a spindle housing secured to said frame for adjustment forwardly and rearwardly, a regulating wheel spindle rotatably supported in the spindle housing, and motion transmitting means interconnecting said spindle and the spindle drive shaft, the pivotal adjustment of the frame being effective to; adjust" the: spindle; the spindle drive shaft and the:

bearing, drum about said axis;

4'. A regulating wheel assembly for a centerl'ess grinder and comprising amain housing which is movable laterally in the grinding operation, a drive motor rigidly secured to the main housing, a bearing drum supported in said main housing for pivotal movement on a lateral substantially horizontal axis, a shaft driven by said'rnotor and rotatably supported in the main housing on said axis and projecting into said bearing drum, a spindle drive shaft rotatably supported in said bearing drum for pivotal movement therewith and projecting rearwardly of the drum and the-main housing, motion transmitting means interconnecting the motor driven shaft and thespindle drive shaft to effect a driving connection therebetween in 15 any pivoted position of' the drum, a frame secured to the main housing for pivotal adjustment on said axis and rotatably supporting the rearwardly projectingi end portion of the spindle driveshaft, a spindle; housing secured.

to said frame for adjustment forwardly and rearwardly;.

mentwith' said framebelow said axis whereby to adjust:

the; pivoted position of the frame and similarly to adjust the pivoted position of the spindle, the spindle driveshaft. and the. bearing. drum.v

References Cited in the fileof this patent UNITED STATES PATENTS 1,985,433 Turner Dec. 25,, 19,51

FOREIGN PATENTS 562,362 Great Britain June 28, 1944'

Images