US1779618A

US1779618A - Centerless grinding machine

Info

Publication number: US1779618A
Application number: US237464A
Authority: US
Inventors: James A Phelps
Original assignee: Individual
Current assignee: Individual
Priority date: 1927-12-03
Filing date: 1927-12-03
Publication date: 1930-10-28
Anticipated expiration: 1947-10-28

Description

Oct. 28, 1930. JfA. PHL-:LPS

CENTERLESS GRINDING MACHINE Filed Dec. 3. 1927 2 Sheets-Sheet 1 GR om.. wm Q. Il

J. A. PHELPS Oct. 28, 1930.

. CIEN'LlEaRLEsS GRINDING MACHINE 2 Sheets-Sheet 2 Filed DeC. 3, 1927 um i@ i l mmf. N

n A NN Patented Oct. 28, 1930k l UNITED STATES JAMES A. PHELPS, F CLEVELAND, OHIO CENTERLSS GRINDING MAC-EINE application med December s, 1927. serial No. 237,464.

As the name implies, a centerless grinding machine is one of that type which supports or carries the work ground thereby without availing of the center supporting 'method so commonly called for grinding machines. This method of positloning the work has many obvious `advantages relative to the speed and accuracy with which the machine functions.

The centerless grinding machine generally speaking comprises a grindin ,Wheel that revolves with a comparatively igh peripheral speed and a regulating wheel mounted in spaced relationv with respect to the grinding wheel and turnin with a relatively small circumferential velocity; The work is posi-` tioned intermediate these wheelsand due to their dierences in peripheral speeds, .a grinding action takes place.

-It is common practice to employ a blade intermediate the wheels aforesaid for the purpose of assisting in vthepositioning of the work. It will be apparent that work positioned in this manner will be held by supporting points which are non-equidistantly spaced thereabout; that is, the distance between the first and second supporting points Y is 90 as is the distance between the second and third, while that between the third and 3o first is 180. Needless to say this condition does not add to the trueness and ineness of the finished work turned out by the machine. In addition there is the disadvantage of having a comparatively stationary support employed in conjunction with two so-called movable supporting points.

I propose by this invention to obviate the above noted disadvantages by providing a centerless grinding machine in which the work out interfering with the operating is supported by three equidistantly spacedv being a space provided between them and the grindin wheel and it is in this space that the wor is positioned. By this method the `work is supported at points substantially 120 apart. f

Centerless grindin machines are usually employed to grind cy indrical work by 'either one of two methods, either the straight through grinding method or .the in-feed grlnding method. The first method is used when the work is entirely cylindrical and lacking in any shoulders or protruding parts, the in-feed method being availed of with that type of work having shoulders, such as shackle bolts, yoke pins, valve-tappe'ts. A machine made in accordance with this inven-y tion does not depart from this conventional practice but includes' novel construction which facilitatesthe operation of themachine when the in--feed method is employed. This feature is obtained b providing certain instrumentalities for a usting the carrier rolls to size of work and additional instrumentalilties which operate to move one of the carrier rolls for the purpose of positioning the work when the machine is to be used in connection with'the in-feed method.

A still further object of Vthis invention is to Y provide a centerless grinding; machine in which the grinding wheel may be adjusted to various angles with respect to the Work Withmethods of the machine. T attain this end y mounting the grinding wheel onta bracket having eye-bolts which move in an arcuate T-groovein a support. This eliminates any pivotal construction which would normally interfere with the operation of the machine.

In the now known types of centerless grinding machines, adjustment to the size of work is obtained by variations in the position of theregulating wheel, as Well as the supporting blade. An advantage of paramount importance obtained by my centerless grinding machine is the feature of imrobility of the regulating wheel notwithstanding the'factth'at the machine is adjustable to accommodate work of widely varying dimensions. While my machine includes structure that permits of the adjustment of theposition of the grind- Apositions of the carrier rollswhereb are held against the regulating wheel by'gravity action. It might be well to mention that one of the main differences of construction between my machine and the conventional machine of this type is that in the old form there is a lateral relationship between the grinding and regulating wheels while my invention provides for a vertical relationship between these parts. That is, the grinding wheel is superimposed over the regulating wheel and it is such a construction as this that permits me to avail of gravity action for the positioning and adjustment of the carrier rolls to the size of the work.

Various other more detailed objects and advantages will in part become apparent and in part be hereinafter stated as the description of the invention proceeds. For a complete understanding thereof, reference may be had to the following description and accompanying drawings, in which Figure 1 is a side view of a centerless grinding machine made in accordance with this invention, parts being br'oken away to more clearly illustrate detailed features of the construction.

Figure 2 is a horizontal cross section taken on the line 2--2 of Figure 1, parts being broken away and shown in section.

Figure 3 is a detailed plan view 'of the bracket on which the grinding wheel is mounted.

Figure 4 is a vertical cross section taken on the line 4-4 of Figure 1, and

Figure 5 is a vertical cross-section illustrating more particularlythe construction of 'the adjusting instrumentalities.

Throughout the various figures of the drawings, corresponding parts are designated by like referencecharacters.

While the preferred form of the invention is herein set forth, it is to be understood that I am 'not to be limited to the exact construction illusrated and described because various modifications in these details may be provided in putting the invention into practise within the scope of the appended claims.

KA grinding machine made along the lines of this invention includes any appropriate support or stand illustrated in the drawings somewhat diagrammatically and designated by the reference character A. The stand A is of what might be called elongated formation and is provided intermediate its ends with a large groove or cutaway portion B.

A regulating wheel C is fixedly mounted in the groove B. This is also shown diagrammatically in the drawings as the particular mounting of this wheel has no bearing on this invention.

Positioned over the top of the stand A at one end thereof is a supporting plate 1 having an arcuate T-groove The plate 1 is also preferably formed with a flange 3 co-aligned with the groove 2. A top plate 4 having a groove 5 complemental to the flange 3 and adapted to receive the same is positioned above the plate 1. Plate 4 carries headed bolts 6 which extend into the T-groove 2 whereby the plates 1 and 4 are held in position with their adjacent faces in contact. It will be apparent that this connection affords a movable relationship between these parts so that the plate 4 may slide over the plate 1 and be guided in its movement by the iiange 3 and groove 2. At one side of plate 4 is an upstanding bracket 7. This bracket is supported by the curved flange member 8 which also projects upwardly from the plate 4. Fastened to the tops of the bracket 7 and the flange 8, in any suitable manner as by bolts, is a plate 9 having an opening therein. The plate 9 extends beyond the bracket 7 and the opening is in this extension. The bracket 7 has grooves 10 in its outer face which cooperate with flanges 11 on a complemental supporting member 12 for the purpose of governing the relative movement between the member 12 and the bracket 7. The member 12 has a hollowed-out shoulder or bracket 13 and a threaded opening 14. A screw-threaded arm 16 extends intothe opening 14 and passes through the opening in the plate 9 and has a hand-wheel 15 at one end thereof. It is notable that the end of the arm 16 carrying the wheel 15 is enlarged at 17 to provide a shoulder which bears against the plate 9. The hand-wheel 15 is operable to raise and lower the supporting member 12 for purposes to be hereinafter more fully set out. A grinding Wheel 18 of proper abrasive material is pivotally mounted in the bracket 13. It will be apparent that a movement of the supporting member 12 will cause a corresponding movement of the grinding wheel 18. l

Going back to the support or stand A, it is noted that this stand has top portions 19 and 2Q in which are grooves 21 of the particular formation clearly shown in Flgure 4.

Movable base members

22 and 24 having flanges 23 corresponding in shape to the grooves 21 are mounted on the top portions 19 and 20 so that the flanges 23 fit in the grooves 21 whereby the

members

22 and 24 are movablelongitudinally with respect to the stand A. The

members

22 and 24 have

upstanding ears

25 and 26 throu h which extend

pivot members

27 and 28. arried by the

members

22 and 24 are

brackets

29 and 30 which are mounted on the

pivots

27 and 28.

Referring more particularly to Figure 1, it is noted that the

brackets

29 and 30 extend beyond the top portions 2O and 19 and over the regulating wheel C where their ends terminate short of one another. Pivotally mounted in the ends of the

brackets

29 and 30 are carrier rolls or wheels 31 and 32. The carriers 31 and 32 rest on the regulating wheel C. Certain mechanism is provided for adjusting the positions of the

members

22 and 24 while additional ,adjusting instrumentalities are will cause longitudinal movement of the member 22 and a corresponding adjustment of the carrier 32. In connection with the base member 24 I provide two sets of operating instrumentalities for'the purpose of adjusting the position of the carrier member 31 mounted thereon. A threaded shank 37 extends into the opening 33 in the member 24 but is in a sliding engagement therein. The shank 37 extends from a hand-wheel or operating member 38. A second operating member 39 having a hub portion 40 is also carried by the shank 37 and is threaded thereon. A portion of the hub 40 is reduced and extends into the counterbore 34 as shown at 41. The reduced portion of the hub 40 is provided with a circumferential groove 42. A pin 43 is threaded in an opening in the member 24 and has an end entering the groove 42. This pin 43 is provided with a dog point which functions to prevent relative rotation between the hub 40 and member 24 when the pin 43 is screwed down tight. When this pin is loose, hub ,member 40 may be rotated with respect to the member 24. The shank 37 extends through a divided clamp 44 which may be tightened by means of a bolt and nut 45 to prevent rotation of the shank 37.

Rolls 46 may be suitably mounted on the plate 1 to receive the work as it comes from the grindingv wheel. The rolls 46 should preferably be substantially co-alignedwith the carriers 31 and .32, although it is true that an exact co-aligned relation between these parts is not always necessary 1n view of the adjustability of the carriers 31 and 32.

When the machine is used to grind work by the straight through method the grinding wheel 18 is positioned at an angle w1th respect to the work. It is this angular relationship that feeds the work straight through the machine, no other means for this purpose being necessary. Adjustment to 'the slze of the work is obtained by operating hand wheels 36 and 38 to properlyv locatel the carriers 31 and 32.L These carriers are also adjusted to compensate for the wear of the grinding wheel when accurate work 1s desired.

When the work the in-eed method for the grinding thereof.

In-the operation of the machine to carry out this method the grinding wheel is held at right angles with respect to the work which is not fedstraight through, in the manner described in the preceding paragraph, but is inserted from the side in conjunction with a proper 'manipulation of the carrier 31. As in the straight through method the hand wheels 36 and 38 are employed to adjust the carriers to the size of the work and to compensate or wear, but the intermittent move- `ments of the carrier 31 to allow for the insertionand removal of the work, are caused by the operation of the member 39.

When the hand-wheel 38 is to be operated to adjust the position of the member 24, the bolt and nut 45 must be loose while the pin 43.isscrewed down tight so that relative r0- tationbetween the hub 40 and member 24 is avoided. Upon turning the wheel 38, the shank 37 will be rotated to cause the desired shifting of the base member 24. When it is desired to employ the operating member 39 for the purpose of adjusting the carrier roll 31, the nut and bolt 45 are tightened to rigidly clamp `the shank 37 in thel clamp 44 and the pin 43 is loosened but ,one end thereof maintained in engagement with the groove 42. The operating member 39 is now free to rotate while the shank 37 is rigid. The relative movement of these parts. will cause the required movement of the member 24 as previously set out. i

If it is desired to operate the machine with the grinding wheel at an angle with respect to the work, this may be done by shifting the top plate 4 over the supporting .plate 1.

.The groove 2 and bolts 6 provide for the kthe vertical diameter of the grinding wheel 18. It will be apparent that by varying the angle of the wheel with respect to the work, variety in the speed with which the work is fed through the machine is aii'orded. The plates 1 and 4 provide for a wide range of angular adjustment of the. grinding wheel in the manner hereinbefore set out. While it is intended that the carriers 31 and 32 may be adjusted to accommodate work, the dimensions 'of which vary within reasonable range, the machine is capable of accommodating work of widely varied dimensions on account of the adjustability of the grinding wheel 18. However, the main reason for incorporating the Jfeature of adj ustability into has any protrudingpart's" such as shoulders, it is necessary to avail of` the mounting of the grinding Wheel is to compensate for the Wear of the same. These Wheels may be used until they have beenl Worn down to a very small size when they are adjustably mounted in the manner described.

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

1. In a oenterless grinding machine of the class described, the combination of a grinding wheel, a stationary regulating Wheel, and means for positioning work intermediate the grinding and regulating Wheels, said last named means being adjustable to accommodate Work of varying sizes.

2. In a centerless grinding machine of the class described, the combination of a stationary grinding Wheel, a regulating Wheel, and means intermediate the Wheels for positioning Work so that the grinding and regulating Wheels 'are diametrically oppositely disposed with respect to the Work whereby the latter is adapted to be operated on by the grinding wheel, said last named means being adjustable to accomlnodate Work of varying sizes.

3. A oenterless grinding machine of the class described comprising, in combination, a grinding Wheel, a regulating Wheel said grinding and regulating wheels being in effect stationary, and instrumentalities intermediate said Wheels for positioning Work to be op= erated on thereby,4 said instrumentalities being adjustable to accommodate Work of varying dimensions.

4. A oenterless grinding machine of the class described comprising, in combination, a grinding Wheel, means for holding the Work in position to be operated on by the grinding Wheel, instrumentalities for adjusting the last-named means to accommodate Work of varying dimensions, and additional mechanism associated with the last-named instrumentalities operable'to vary the position of a portion of the first-named means.

5. Grinding mechanism of the class described comprising, in combination, a grinding Wheela regulating wheel, and carrier members in engagement with the regulating Wheel and spaced from the grinding wheel.

6. Grinding mechanism of the class described comprising, in combination, a grinding wheel, a regulating wheel, complemental carrier rolls in engagement with the regulat ing Wheel and spaced from the grinding wheel and each other, and means for adjusting the position of the carrier rolls.

7. Grinding mechanism of the class described comprising, in combination, a grinding Wheel, a regulating wheel,carrier rolls in engagement with the regulating wheel, the carrier rolls being pivotally mounted in brackets, and instrumentalities for moving said brackets whereby the carrier rolls are adjustable to accommodatethe varying sizes of Work.

8. A oenterless grinding machine of the l class described, comprising, in combination, a stand, a regulating wheel mounted on said stand, a grinding Wheel superimposed overl said regulating Wheel, and instrumentalities in engagement with said regulating Wheel for holding Work in position to be operated on by the grinding Wheel, said instrumentalities being adjustable by mechanism operable to let them fall under gravity action or be moved upward against this force.

9. A oenterless grinding machine of the class described comprising, in combination, a regulating Wheel mounted on said stand, movable base members carried by the stand, carrier rolls connected to said movable base members and in engagement With the regulating Wheel, a grinding Wheel, instrumentalities for adjusting the position of said base members and additional instrumentalities for adjustingthe position of one of the base members whereby the machine is adapted ior grinding by theso-called in-feed method.

10. Mechanism for positioning Work in a grinding machine comprising, in combination, carrier members, brackets on said carrier members, said brackets being pivotally mounted on said base members, the base members being movable with respect to one another Whereby adjustment of the position of the carrier members adapts the machine to work ofafarying dimensions.

In testimony whereof I afi-ix my signature.

JAMES A. PHELPS.