US2897636A

US2897636A - Work rest for a centerless grinder

Info

Publication number: US2897636A
Application number: US624920A
Authority: US
Inventors: Roger S Pyne; Albert H Tompkins
Original assignee: NORMAN IND Inc VAN
Current assignee: NORMAN IND Inc VAN; VAN NORMAN INDUSTRIES Inc
Priority date: 1956-11-28
Filing date: 1956-11-28
Publication date: 1959-08-04
Anticipated expiration: 1976-08-04

Description

Aug. 4, 1959 R. s. PYNE ET AL WORK REST FOR A CENTERLESS GRINDER 2 Sheets-Sheet 1 Filed Nov. 28. 1956 INVENTORS 065)? 5: PY/VE ALBERT/i mMPK/ALS' u BY @uzw w? ATTORNEYS 4, 1959 R. s. PYNE ET AL 2,897,636

WORK REST FOR A CENTERLESS GRINDER Filed Nov. 28. 1956 2 Sheets-Sheet 2 F/G. I

go 55 g fiz 7 18 F/G. 6 j 0 /Z if g Z2 INVENTORS ROGER s. PY/VE ALBERT lf. TOMPK/NS BY WORK REST FOR A CENTERLESS GRINDER Roger S. Pyne, Longmeadow, and Albert H. Tompkins,

East Longmeadow, Mass, assignors, by mesne assignments, to Van Norman Industries, Inc., Springfield, Mass., a corporation of Massachusetts Application November 28, 1956, Serial No. 624,920

2 Claims. (Cl. 51-103) This invention relates to improvements in a centerless grinder and, more specifically, to an improved work rest for a centerless grinding machine.

It is the general object of the invention to provide a work rest upon which a work support blade can easily be mounted and which is particularly adapted to be adjusted toward and away from the grinding wheel or the associated regulating Wheel in the usual manner and which is also adapted to provide swivel adjustment of the work support blade whereby to adjust the angular disposition of the work-engaging surface of said blade.

Other, more specific objects as well as advantages of the invention will become apparent to those skilled in the art from the specification wherein a presently preferred embodiment is described with reference to the attached drawings. However, it should be understood that the description of the preferred embodiment of the invention is not to be taken as limiting or defining the scope of the invention, the claims forming a part of this specification being relied upon for that purpose.

Of the drawings,

Fig. 1 is a schematic view of a centerles grinding machine which incorporates a work rest provided in accordance with this invention;

Fig. 2 is an end view of the work rest showing portions of a grinding wheel and regulating or control wheel and also showing a fragment of the work rest slide, the grinding wheel, regulating wheel and slide comprising conventional elements of a centerless grinder;

Fig. 3 is an elevational view of the work rest, a portion thereof being shown in vertical section to illustrate a detail, the elevation being taken as viewed from the right in Fig. 2;

Fig. 4 is a plan view of the lower or base member of the work rest;

Fig. 5 is a plan view of the upper adjustable member of the work rest;

Fig. 6 is a plan view showing the upper and lower members of the work rest assembled;

. Fig. 7 is an end view generally similar to Fig. 2 but showing the upper member of the rest pivoted in a clockwise direction; and

Fig. 8 is similar to Fig. 7 but showing the upper member of the work rest and the work supporting blade pivvoted in a counterclockwise direction.

In centerless grinding machines which include a rotatable grinding wheel and a rotatable regulating wheel, a work rest is generally mounted on the bed of the machine between the grinding and regulating wheels to support the work in engagement with the said wheels in what is commonly referred to as the grinding throat. In most centerless grinders, the regulating wheel assembly is adapted to slide on the machine bed so as to move the regulating Wheel toward and away from the grinding wheel in a plane which is transverse of the machine to accommodate work of different sizes and to grind work .to selected diameters. Some centerless grinding machines proi '4, 1956, shows but one exampleof a centerlessgrinder" 7 2,897,636 Patented Aug. 4, 1959 "ice vide for similar rectilinear adjustment or movement of the grinding wheel. It is also a common practice to mount the Work rest on a slide movable along the bed on suitable ways or the like, and means are generally provided for selectively securing the work rest slide to the regulating Wheel slide whereby the work rest can be moved rectilinearly along the bed with the regulating wheel assembly when it is desired to do so.

In most work rest constructions, means are provided for detachably securing a work supporting blade thereto, the blade being disposed generally vertically between the grinding wheel and the regulating wheel with its upper generally horizontal edge supporting the work in engagement with the regulating wheel and the grinding wheel.

As the work is being ground, it is rotated by the regulating wheel on a generally horizontal axis which substantially coincides with the longitudinal center line of the work unless the work is substantially out of round. While the upper, generally horizontal edge of the blade may be fiat so as to present a substantially horizontal surface in engagement with the work, in most constructions the said upper edge of the work support blade is inclined or tapered so as to present a work-engaging surface which is angularly related to the horizontal. The taper at the top edge of the blade provides an angle with the horizontal which opens toward the regulating Wheel whereby the work will tend to climb the inclined surface toward the grinding wheel when the regulating wheel is advanced toward the work rest and toward the grinding wheel.

Some work support blades are provided with a shallow V-shaped top edge, the work engaging only one of the inclined surfaces when the regulating Wheel advances the work into engagement with the grinding wheel.

Experience in the art of centerless grinding has shown that most workpieces should not be supported so as to rotate on an axis or center line in a common plane or line with the axis or centers of the grinding wheel and the regulating wheel. It is the most common practice to support the work so that its axis or center of rotation will be disposed above the common plane or line of the axes or centers of rotation of the regulating wheel and grinding wheel. The best rounding is achieved by placing the workpiece well above the wheel centers on a blade having a steep angle of inclination. However, the steeper the angle, the greater the wedging between work blade and regulating wheel and the greater the likelihood of thrusting the work upwardly out of contact. In general, steep angle blades can be used for light cuts and shallow angle blades are used for heavy cuts. Thus, it is desirable to provide angle adjustment for work support blades to adapt a centerless grinder for various workpieces.

A work rest constructed in accordance with the present invention provides for adjustment of the angle of inclination of the blade surface which engages and supports the Work, without requiring replacement or modification of the blade.

' In Fig. 1 there is shown a typical application for a work rest 10 constructed in accordance with this invention to support work such as the workpiece W for engagement by a grinding wheel 12 and a regulating wheel 14. In accordance with conventional practice, the work rest It) is secured to a slide 16 for rectilinear adjustment on the bed 17 of the machine as indicated by the direction arrow A whereby to advance the work rest toward or away from the grinding wheel 12. It is believed to be unnecessary to show the machine bed or theregulating wheel assembly or the grinding wheel assembly in any detail because such elements are common to centerless grinder construction. Our pending US. patent application Serial No. 582,704, filed May which includes a work rest adapted to be adjusted rectilinearly on the bed. As more fully shown and described in that application, the work rest slide can be selectivelysecured to a regulating wheel slide 19 whereby to move the work rest with the regulating wheel toward or away from the grinding wlheel. It will be understood that similar arrangements can be made for the work rest now being described.

Adjustment of a conventional work rest rectilinearly as indicated by the arrow A toward or away from the grinding wheel 12 and relative to the regulating wheel 14 is generally effected to accommodate workpieces of different diameter. That is, the work rest is moved toward the grinding wheel 12 to accommodate workpieces of small diameter and it can be moved away from the grinding wheel for workpieces of greater diameter. With the work rest provided in accordance with the present invention, rectilinear adjustment as indicated by the arrow A is effected not only to accommodate workpieces of different diameter but similar rectilinear adjustment is coordinated to angular adjustment of a work support blade 18 as will be described.

As previously mentioned, the work rest of this invention provides for adjustment of the angle of inclination of the top surface of the work blade. The work rest 10 is adapted to the foregoing purposes by providing a base member 20 as a support for a pivotally adjustable top member 22 which is detachably secured thereto and which can be secured in adjusted position.

The base member 20 is of elongated generally rectangular form and extends generally longitudinally of the machine or generally normal to the transverseplane of relative movement between the grinding wheel and the regulating wheel. The said base member has an inclined side 24 and a vertical side 26, but the vertical side is joined by another inclined longitudinally extending surface 28 adjacent the top of the base member. The top surface 31 of the base member 20 is curved, preferably concave, the arc of the surface being transverse and the surface being concave along the entire length of the base member except for one fiat end portion 32 which provides a platform for attaching work rest accessories such as an end stop or the like. The concave upper surface provides a cradle or bearing surface for pivotally supporting the upper member 22 of the work rest, said upper member being secured to the base member 20 by screws or tie down bolts extending into the longitudinally spaced tapped

holes

34, 34. The said screws can be extended through the base member to secure the work rest to the slide 16 or other work rest securing means can be, employed if desired.

The upper member 22 is also elongated and has a curved lower surface 35, convex in the embodiment shown, which is complementary to the top surface of the base member 20 and is seated thereon for swivel or pivotal movement of the upper member relative to the base member. The

sides

36 and 38 of the upper member are inclined similarly to the inclined surfaces 24 and 23, respectively, of the base member so that the aforesaid inclined surfaces will reside in a common plane when the upper member is located on the base member in such a position that the work support blade 18 resides in a substantially vertical plane. An elongated slot 40 is provided longitudinally of the upper member 22 in its upper surface to receive the work-supporting blade 18. The blade 18 is detachably secured within the slot 40 by two or more

set screws

42, 42 which are spaced apart longitudinally of the member 22 and extend transversely thereof.

The blade 18 can be provided in any conventional form, that shown being merely exemplary. It is desirable in the construction of work blades to provide a hardened steel insert 44 at the top edge thereof for engagement with the work W. The top surface 46 of the insert or of the blade may be at a right angle to the sides of the blade but, preferably, it is shown.

As best shown in Figs. 7 and 8, the upper member 22 can be pivoted transversely on the base member 20, the complementary

curved surfaces

30 and 35 providing a bearing engagement between the two members. The upper member is secured in pivoted position relative to the base member by means of a pair of

screws

48, 48 which extend into the tapped

holes

34, 34 in the base member. The

screws

48, 48 are located adjaccnt the ends of the top member 22 and extend through

transverse slots

50, 50 therein. The end portions of the top member are preferably recessed as indicated at 52, 52 and a collar 54 is provided for each screw 48 to sit in the curved recess 52 over the slot 50 to provide a flat base for the head of the screw.

The pivotal adjustment of the upper member 22 relative to the base member 20 can be in a clockwise or counterclockwise direction as viewed from an end thereof and as illustrated in Figs. 7 and 8. Such pivotal inclined as adjustment or movement of the top member effects similar adjustment of the work-supporting blade 18 whereby to change the angle of inclination of the top surface of the support blade relative to the work W. When the blade and top member of the work rest are pivoted clockwise as shown in Fig. 7, the inclination of the top surface 46 is relatively steep, while counterclockwise pivotal adjustment of the blade and top member 22 as shown in Fig. 8 reduces the inclination of the top surface 46. It will be apparent that the work rest should be adjusted rectilinearly, by movement of the slide 16 on the bed 17, to accommodate angular adjustment of the blade. That is, the rest should be moved away from the grinding wheel when the blade is pivoted toward it, and vice versa, so that a desired spacing between work blade and grinding wheel can be effected.

Accordingly, a work rest constructed in accordance with the present invention permits of the usual rectilinear adjustment, but in addition thereto, the work rest of this invention can be pivotally adjusted to adjust the relative angular dispostion of the Work-engaging surface of the work-supporting blade.

The invention claimed is:

1. A centerless grinding machine comprising a grinding wheel and a regulating wheel which are movable relatively toward and away from each other in a transverse plane, a rest for supporting work in the machine including an elongated base member extending generally normal to the said plane and between the grinding wheel and the regulating wheel, the said base member having a transversely curved top surface providing a swivel seat, an elongated upper member having a bottom surface complementary to the aforesaid surface and seated thereon whereby the upper member can be pivoted clockwise and counterclockwise on the base member as viewed from an end thereof, means for securing the upper member to the base member in pivoted positions thereon, and a work-supporting blade secured to the upper member to extend longitudinally thereof and to project upwardly between the said grinding and regulating wheels for engagement with a workpiece.

2. A centerless grinding machine comprising a grinding wheel and a regulating wheel which are movable relatively toward and away from each other in a transverse plane, a rest for supporting work in the machine including an elongated base member extending generally normal to the said plane and between the grinding wheel and the regulating wheel, the said base member having a top surface which is transversely concave and which provides a swivel seat, an elongated upper member having a convex bottom surface complementary to the aforesaid concave surface and seated thereon whereby the upper member can be pivoted clockwise and counterclockwise on the base member as viewed from an end .5 thereof, said upper member being provided with recessed end portions having transverse slots extending therethrough, screw means extending through said slots and threaded into said base member for detachably securing the upper member to the base member in selected pivoted positions, and a work-supporting blade secured to the upper member to extend longitudinally thereof and to project upwardly between the said grinding and regulating Wheels for engagement with a workpiece.

References Cited in the file of this patent UNITED STATES PATENTS Swanson Dec. 28, 1920 Hopkins Mar. 18, 1947 Riley Apr. 5, 1949 FOREIGN PATENTS Great Britain Sept. 29, 1943 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No: 2,897,636 August 4, 1959 Roger So Pyneet a1 It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should readas corrected below.

Column 4, line 60, and column 5, line 8, before "between", each occurrence, insert therefrom Signed and sealed this 22nd day of December 1959,

(SEAL) Attest:

KARL H. AXLINE ROBERT C. WATSON Attesting Officer Commissioner of Patents