US1509075A - Steady rest - Google Patents

Description

I Sept. 16 1924.

C. H. NORTON STEADY REST Filed Jan. 5. 1921 CHARLES H. Nnn'rnu Patented Sept. 16, 1924-.

uu rsn STATES PATENT OFFICE.

CHARLES H. NO'RTON, OF WORCESTER, MASSACHUSETTS, ASSIGNOR TO NORTON COM- PANY, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

STEADY REST.

Application'filed January 5, 1921. Serial No. 435,097.

To all whom it may concern.

Be it known that I, CHAaLns H. Neuron, a citizen of the United States of America, residing at Worcester, in the county of \Vorcester and State of Massachusetts, have invented certain'new and useful Impro-ve mentsin Steady Rests, of which the following is afull, clear, and exact specification.

My invention relates to a steady rest, and more particularly to an automatic indicating steady rest for supporting the rotating work and indicat'i'ig the extent of the grinding operation.

In accordance with previous theories of grinding, steady rests have been constructed to. support rotating cylindrical work not only on the lower side toward the grinding wheel but also on the side opposite the wheel whereby therest shoe will be fed forward to hold the work firmly against the wheel, and in the usual practice of grinding the operator has constantly adjustedscrew feeding members to force the steady. rest shoe into contact with the work. As a result, if the Work is crowded too much into the wheel, there is, a' tendency for chattering to take place until. the wheel has ground itself out, this vibratory motion being up and down as well as into the wheel. 1t is accordingly an object of my invention to prevent vibration or chattering of the work by applying a force thereto which acts to hold the work away from the wheel and so making it impossible to feed the work into the wheel during. grinding by adjustment of thesteady rest.

y The desirability of an automatically feed ing steady rest has long been recognized and numerous attempts have been made to prov'de a spring pressed rest shoe which will be held against the workwith. a constant pressure. However, due to the fact that vibration has not been eliminated. the spring and the relatively light movable parts ofthe steady rest have formed source-s of vibration and so have required the use v in of positive means for limiting the movement of the steady rest shoe. It accord ngly a further object. of my invention to provide a steady rest with a massive shoe and an automatic mechanism which will keep the shoe in close contact with the workas grinding proceeds and so utilize the mass ofthe steady rest to aid in damping vibratlons.

Furthermore, the operation of grinding 1s ordinarily hindered by the necessity for the operator to caliper the work at intervals, which usually requires stopping the process and in'certain cases removing the steady rest shoe from adjacent the work in order to get at the latter. It is accordingly a still further object of my invention to provide an automatic self-indi ating steady-rest which will indicate the extent to which grinding has proceeded and which in conjunct on with the usual wheel cross feed mechanism may be employed to grind to a predetermined size and, except for wheel wear for whichcompensation may be made,automatically stop grinding when the operation has proceeded to a certain definite stage. A minor-object related to tll} above is to provide a shoe sup porting construction which may be readily swung away from the work'at a point opposite the grinding wheel for any calipering that may be coi'isidered necessary to coniirni the results indicated by a dial on the steady rest.

.Vith these specific objects in view, it is a broad object of my invention to provide a steady rest which will make it feasiblefor the work to traverse relative to the wheel at a speed heretofore not obtained in a grinding machine of this type, due to the necessity for the operator to be constantly adjusting the numerous steady rests required to support a long piece of cylindrical work, and thus to render the process of grind ng rapid and economical and to produce uniform results in production grinding where it is desired to duplicate closely a piece of work previously ground to a required size. I w

With these and other objectsin View, as will appear from the disclosure here'n set forth, my invention resides in the combination of parts described in the sijieciiication and covered by the claims appended thereto.

In the drawings, in which like reference characters indicate l ke parts: i

Figure 1 is a perspective view of my improved steady rest, part of the spring housing being broken away; i

Fig. 2 is a rear elevation thereof;

Fig. is a section thereof, parts being shown in elevation, indicating the manner of its connection to the grinding machine table and the relation of the work to the work shoe at the beginning of the grinding operation;

Fig.4 is a View similar to Fig. 3 of the forward port on of the steady rest, showing the relation of the work to the shoe at the finish of the grinding operation;

Fig. 5 is an end view showing the manner of mounting of the work shoe on the shoe pose-to steady cylindrical work during rotation only on its front side, or on that side which is toward the grinding wheel, and below the line of thrust and to move the stea dying shoe toward the work axis as grinding proceeds, so that in the normal use of my steady rest the work cannot .be fed into the wheel during grindingby means of the steady rest shoe. This will render it impossible for the work to vibrate during grinding, since the shoe being locatedon the lower forward side is so positioned that the wheel thrust tends to move the work along the shoe and away from the wheel. Furthermore, I insure damping the work vibrations by utilizing a massive shoe carrier and maintaining the shoe in contact with the work with suflicient pressure to move the shoe forward as grinding proceeds, but not enough pressureto affect the grinding detrimentally, whereby the shoe carrier, being massive and having considerably inertia as well as having a differentperiod of vibration from that of the work, will not yield to the vibratory impulses which the wheel would ordinarily produce.

A. suitable construction for carrying out this method may comprise a work-steadying .shoe having a. partial cylindrical surface of revolution which corresponds in radius with that of the desired radius of the finished work, whereby I may maintain contact between the shoe and the work only adjacent the nose of the shoe nearest the Wheel so that the curvature of the shoe will not fit the work until grinding has been completed. In order that the operation vmaybe automatic, I may mount the shoe on a massive support which is held 1n contact with the work by suitable mechanism, and I may furthermore provide an indicating-device for registering the movement of the work shoe to give warning when grinding has proceeded to a given stage. In conjunction with the indicator, it is desirable to provide a stopping device adapted to stop the shoe feed automatically.

In order that this invention may be more readily understood, reference is to be had to the accompanying drawingsillustrating one embodiment of a steady rest utilizing the principles of my discovery. As there 1llustrated I have shown my steady rest as comprising a shoe carrier 1 supported by and movable relative to a stand 2 fastened to a. suitable part of the grinding machine table In my preferred form this shoe carrier may take the form of a lever having a relatively massive arm 5 to which the work shoe is connected. The shoe carrying lever 1 I have shown pivoted at 8 to two lugs 9 extending forwardly from the body 2 and I provide means, such as a spring 10, for holding the shoe 6 against the work at all times during a grinding op eration. In the practice of my method'the shoe may be fed manually by suitable mechanism. although I prefer tomake my steady rest, after it is once adjusted, automatic in its action. a i

An. important distinction between my. im-

proved steady rest and those heretofore used is illustrated by the manner in which the shoe bears againstthe work IV during the greater part of the grinding operation so as to exert a force thereon opposed to the downward thrust of the grinding'wheel 7 and also tending to move thework away from the grinding wheel. To allow of the proper adjustn'ient of the shoe so that the force exerted on the work may be applied as above pointed out, I provide a work shoe 6, which I have shown as comprising two concentric bearing surfaces 13 and 1a of equal radius forming apartial. cylindrical surface of revolution. The radius of the curved bearing surfaces 13 and 14 is preferably substantially equal to the radius of the work when ground to size, as shown in Fig. 1, and to minimize wear I may construct them of any suitable wear-resisting material, such ashardened steel. I may, moreover, utilize a shoe having a continuous curvature instead of the two curved bearing surfaces shown.

The .work shoe is mounted .on a shoe holder 15 loosely pivoted adjacent its upper end by means of the screw 16. A spring 17 is-arranged between the head of this screw and a shoulder 18 formed by a countersink in the shoe holder, this spring thus seiwing to press the upper end of the holder toward the lever 1. At its lower end this shoe holder is formed at the middle with a bearinglug 21 and .is tapered from this lug to the sides, as shown in Fig. 5. The-purpose of this arrangement is toallow lateral rocking of the shoe holder so that the shoe 6, which may be of substantial .width, may

align itself accurately with the work. The shoe is held clamped on-the holder between a shoulder 22 and the set screw 23 in the usual manner to allow of the substitution of different sized shoes to fit the work. In order -to tip the shoe 6 away from and toward the wheel around the bearing lug 21 as a pivot, I provide, a set screw 24 (Fig.

3). The spring 17 coacts with this set screw to hold .the shoe holder 111 any adjusted desired size when supported between centers and the steady rest shoe is then brought up against the work and lts angular position adjusted by means of the screw 24: until its bearing surfaces fit the work, as shown in Fig. 4.

From this construction it will be obvious, by reference to Fig. 3, that when a piece of work to be ground which, let us say, is .005" oversize, isfirst placed in the machine and the shoe 6 is brought up against the work, it will have only a substantially line contact'with the work at a point below the work and adjacent the wheel and the work will be entirely unsupported bythe bearingsurface opposite the wheel until the work is ground: to size, so that there is no chance whatsoever of the work being crowded into the wheel with the features.

s a means for connecting the spring 10 with the lever 1, 1 have shown the arm 11 of the lever 1 provided with a gear sector 26 meshing with a gear sector 27 rigidly cured to the shaft 28 extending transversely of the body or stand 2. One end of this shaft extends outside the body casing where it is rigidly connected to one end of the spiral spring 10,'theother end of the spring being connected to a spring housing 29 which is rotatably mounted on the annular stud 30 and can be locked in position by a set screw 31. The spring 10 can by this means be suitably tensioned to hold the shoe in contact with the work so that the massive shoe carrier may damp the vibrations, the actual pressure of the spring being determined by the nature of the work, the couchtions of grinding and the accuracy 1n re sults desired. The stud 30 is provided with a plurality of holes 32, any one of which can be engaged by the set screw 31 when the housing 28 is turned by a su table tool, such as a spanner wrench, to align theseparts. In order to require as little attention on the part of the operator as possible, 1 provide a stop for limiting the forward motion of the shoe carrying lever l and this may take the form of a set screw 33 mounted in a lug 3+ projecting rearwardly from the body 2 and provided with the usual lock nut I have shown the inner end of tlns screw 83 located in the path of an arm 36 which may be made integral withthe sleeve carrying the gear sector 27. By the useof this stop the finishing cuts will be made with the bearing surfaces on the shoe 6 s mply engaging the surface of the work without exerting pressure thereon. D

Another important feature of my invention is the provision of indicating means on the steady rest to tell the operator at a attendant oh ect iona ble glance when the work is ground to size, or

to indicate the wear of the wheel where a positive stop is'employed in thecross-feed mechanism. Any suitable indicator for showing small variations in size may be employed, but I have illustrated an Ames dial indicator 37 suitably mounted on a bracket 38 at the rear of the rest body :2 and operatively connected to the shaft 28 by any suitable means, such as the arm 39 rigidly connected to the end of the shaft and a lever 40 connectedas by means of a screw -ll to the bracket 38. he arm 39 "acts on the relatively short arm of the lever -10, while the long arm of said levercooperates with the movable spring pressed plunger 44 of the indicator the motion of the plunger being communicated to the hand on a dial by a rack and pinion mechanism, as is well known. It will be seen from this construction that any movement of the shoe 6 is greatly magnified on the hand on the indicator. The levertt) has a very limited swinging movement and since any lost motion be tween it and its connecting screw 451 would result in inaccuracies in the reading on the dial indicator if the lever were pivoted about the screw, I pivot the lever on the knife edge d2 against which it is held by alight spring 43, and to permit such pivotal movement about the knife edge, I make the screw 41 slightly smaller than the hole in the lever 40. A set screw 45 limits the swine of the lever -l0'in one direction and this is preferably adjusted so as to allow less than one complete revolution of the hand on the indicator.

I so arrange therelative positions of the dial and the hand of the indicatorthat the hand will point to zero on the scale when the arm 36 is up against the stop screw 33 and the work is ground. to size; I prefer to use some kind of indicator, so that my steady rest will be a precise instrument for producing duplicate work, and to avoid any difliculty which the operator might otherwise meet in attempting to ascertain whether the arm 36 was up, against the stop screw The dial of the indicator is preferably graduated in thousandths of an inch, although any suitable graduation maybe utilized, and in grinding operations of this sort where successive pieces are ground to duplicate sizes, the cross-feed mechanisnr is provided with a postive stop to limit move ment of the wheel into the work. If there has been appreciable wheel wear, when the wheel feed mechanism has reached the stop, the work will be oversize; As a consequence, the hand on the dial'indicator will not be turned to zero and the operator can read directly the amount of wheel wear and then feed the wheel the indicated amount by the usual micrometer feed adjustment and thus bring the work to the desired size and the indicator to zero.

or opening 48 on the body 2 of the rest.- To lower the shoe (3 and, hold it in lowered position, the operator merely presses on the handle until the latch engages thenotch. The latch is released to allow the spring 10 to return the shoe by pressing it toward the handle.

To clamp the steady rest to the work table, I may employ any suitable means such as the clamping means 50 which is substantially the same as that shown and described in the patent to W'ilcox et al No. 1,214,629 dated Feb. 6,. 1917.

It will be-seen from the foregoing disclosure that I have produced an exceedingly fine precision device in the form of an indicating steady rest for producing duplicate work with a minimum of attention from the operator and which, because of the manner in which it supports the work, causes a minimum of wheel wear and avoids vibration of the work, thereby increasing production and the life and efiiciency of the grinding machine on which it is used.

It is obvious that changes may be made in the specific construction of my device and that equivalent elements may be substituted for the parts herein disclosed without departing from the scope of my invention as expressed in the claims appended hereto.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A steady rest for grinding machines comprising a stand, a member movably mounted on said stand which is arranged to serve as the solesteadying support for the work during grinding, and means to move said member and apply pressure on the front side only of the work and thereby tend to hold the work away from the wheel and prevent vibrations.

2. A grinding machine steady rest for producing cylindrical work comprising a supporting stand adapted to be. mounted on the machine, a relatively massive work support movably mounted on the stand and having a workengaging surface thereon, and means for automatically moving said support and holding it in. contact with the front-side only of the work during the initial grinding operation, whereby vibrations of the work may be damped by the inertia of the support.

3. A grinding machine steady rest for producing cylindrical work of a given size comprising a supporting stand, a work-engaging shoe movably mounted on said stand.

for initial engagement only with that side of'the work which is toward the grinding wheel, means including a massive body to maintain contact of said shoe with the work and damp vibration thereof, and means to render said shoe incapable of bearing against the work on the side thereof which,

isopposite the wheel before the work has been ground tothe required size. I

4. A grinding machine steady rest for producing cylindrical work of a given size comprising a supporting stand adapted to. be mounted on the grinding machine, a work shoe movably mounted on said stand and having a partial cylindrical surface, the ra dius of which is substantially equal to that desiredfor the finished work, means tohold said shoe in a line contact with the work on that side thereof which is toward the grinding wheel and below the line of contact between the wheel and the work, said means being capable of moving the work stantially uniform pressure to said carrier to hold said shoeagainst that side only of the work which is adjacent the wheel during substantiallythe entire grinding operation and to move the shoe toward the work axis as grinding proceeds until the cylindrical surface of the shoe is in contact with the work at the completion of the grinding operation.

6. A grinding machine steady rest for producing cylindrical work comprising a stand adapted to be supported on the grinding machine, a relatively massive shoe carrier pivotally mounted thereon for an up ward rocking movement, a work-engaging shoe on said carrier which is arranged to serve as the sole steadying support for the work, and automatic means for exerting pressure against said carrier to hold said" shoe in engagement with that side only of the work which is toward the grinding wheel and belowthe line of contact between the wheel andthe work, whereby vibration of the work is damped.

v7; A grinding machine steady rest comprisinga stand adapted to be mounted on the grinding machine, a work-steadying member pivot-ally mounted on said stand,

and. means for moving said member and holding it against the -work during the ,grinding operation, comprising ashaft, a

mg machine, a relatively massive lever pivoted thereon, a work shoe mounted thereon,

a gear sector on said lever, a gear on the stand engaging said sector, and a spring connected with said gear toswing the work shoe into engagement with the work.

9. A grinding machine steady rest comprising a stand adapted to be mounted on the grinding machine, a work-steadying shoe movably mounted on said stand, said shoe having a pantial cylindrical surface, the radius of curvature of which isequal to that of the finished work, means to adjustably position said shoe so that it will initially contact with the work on that side only which is adjacent the grinding wheel, and means for feeding the shoe as grinding proceeds so as to support the work only on the side towards the grinding wheel until the curvature of the work fits the curvature of the shoe. i

10. A grinding machine steady rest comprising a stand adapted to be supported on the grinding machine, a shoe carrier movably mounted on said stand, a shoe adjustably mounted on said carrier, said shoe having a partial cylindrical surface adapted to bear against the work, and means providing a rocking support between the shoe and carrier whereby the shoe may be automatically aligned with the axis of the work by engagement with its periphery.

11. A grinding machine steady rest comprising a stand adapted to be supported on the machine, a shoe carrier movably mounted on said stand, a shoe having a work supporting surface, adjustable means to locate said shoe on the carrier so that the shoe may contact only with the front .side of the work and means to move the carrier in such a. direction that ",the shoe will support the work only on its front side as grinding proceeds.

12. A grinding machine steady rest for producing cylindrical work comprising a shoe carrier movably mounted on said stand, a work-engaging shoe of substantial width movably mounted on said carrier, said shoe having a partial cylindrical surface whose radius is substantially equal to the radius of the finished work, means for moving and holding said shoe against the work, and means providing a universal rocking support between the shoe and carrier whereby the shoe can be rocked to align it with the work axis and also to cause the cylindrical surface to fit the work at the completion of the grinding operation.

13. A grinding machine steady rest for producing cylindrical work comprising a stand, a work-steadying member movably mounted on said stand, means for moving said member and holding it against the work during the grinding operation, and precision means for indicating to the operatorwhen the work has been ground to the desired size. 7

let. A grinding machine steady rest comprising a stand adaptedto be mounted on the grinding machine. a Work-steadying member movably mounted on said stand, means for moving said member and holding it against the work during the grinding operation, and means cooperating with said member comprising an indicator to inform the operator of the amount of wheel wear.

15. A grinding machine steady rest comprising a stand adapted to be mounted on the grinding machine, a work-steadying member pivotally mounted 011 said stand, means for moving said member and holding it against the work during the grinding operation, and precision means on said stand cooperating with said member for indicating to the operator when the work has been ground to the desired size, comprising a dial indicator and movement magnifying means between said member and the indicator.

16. A grinding machine steady rest for producing cylindrical. work of a given size comprising a stand, a work-steadying shoe movably mounted on said stand, means for moving said shoe and holding it against the work during the grinding operation, means for stopping the movement of the shoe at a predetermined point, and precision means to register the movement of the shoe and indicate when it approaches this point.

17. A grinding machine steady rest for producing cylindrical work comprising a stand adapted to be supported on the grinding machine, a relatively massive shoe carrier pivotally mounted thereon, a work shoe having a partial cylindrical surface, the radius of which is equal to that of the finished work, said shoe being adjustably mounted on said carrier to engage that side only of the work which is adjacent the grinding wheel, a spring operated means for supplying pressure to said carrier to hold said shoe against the work and move the shoe forward until its cylindrical surface is in contact with the work at the completion of the grinding operation, and a precision means to register movement of the shoe and indicate when the work has been ground to size.

18. A grinding machine steady rest comprising a stand adapted to be mounted on the grinding machine, a work-steadying shoe inovably mounted on said stand, means for feedingthe shoe forward as grinding procoeds, and means for effecting a quick movement of the shoe away from the work to permit calipering thereof at a point opposite the shoe, said means permitting automatic return of the shoe to its former steadying position.

movably mounted on said stand, means for moving the shoe asthe grinding proceeds so as to support the work only on the side toward the grinding wheel, means for readily moving the shoe away from the work a distance sufficient to permit calipering the work at a point opposite the shoe, and means for automatically returning and locating the shoe in its initial position.

Signed at Vorcester, Massachusetts, this 81st day of Dec. 1920.

CHARLESH. NORTON.

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