US2465038A

US2465038A - Grinding machine with optical system

Info

Publication number: US2465038A
Application number: US636600A
Authority: US
Inventors: Howard E Reams
Original assignee: Sheffield Corp
Current assignee: Sheffield Corp
Priority date: 1945-12-22
Filing date: 1945-12-22
Publication date: 1949-03-22
Anticipated expiration: 1966-03-22

Description

March 22, 19490 H. E. REAMS I 294655938 I GRINDING MACHINE WITH OPTICAL SYSTEM Filed Dec. 22, .1945

INVENTOR fi flea/kw BY v ATTORNEY Patented Mar. 22, .1949

GRINDING MACHINE SYST Howard E. Beams, Dayton, Ohio, assignor to The Sheifield Corporation, Dayton, Ohio, a corporation of Ohio wrrn OPTICAL Application December 22, 194.5, serial No. 636,600

2 Claims. (01. 51 100) This invention relates to grinding machines and more particularly to grinding machines for accurate reproduction of an exact form or contour,

One object of the invention is the provision of a grinding machine having an adjustable grinding wheel adapted for operation on a workpiece held on a movable work table that is automatically operated through a pantograph system by a follower that traces an enlarged contour of the part to be ground, the construction being particularly adapted to compensate for wheel wear which is evidenced by a viewing means having a fixed line of sight.

Another object of the invention is the provision of a device of this character in which the 'work table is mounted for free movement in a plurality of directions at right angles to one another and carries a work support that can be adjustably positioned so that the workpiece can be properly set in position with respect to the fixed line of sight of a microscope or the like.

Other objects and advantages of the invention will be apparent from the following description, the appended claims, and the accompanying drawing, in which,

Fig. 1 is a top plan View of a grinding machine embodying the present invention;

Fig. 2 is a perspective view of the machine shown in Fig. 1, the bottom portion of the base being omitted; and

Fig. 3 is a transverse sectional view of the work table and work support, showing the connection between the work table and the pantograph.

Referring more particularly to the drawing, in which like parts are designated by the same reference numerals in the several views, In designates a base which provides a support for a work table II and a grinding wheel head l2 which carries a rotatable grinding wheel l3. Projecting upwardly from the base is a post or standard l4 having a horizontally extending beam I5 that carries a board 16, preferably horizontally positioned and adapted to carry an enlarged drawing or formed contour of the part to be ground on the machine. This contour may tak the form of an inked drawing on a scale many times larger than the actual size of the surface formation to be produced-on the work.

The wheel head I'2 is mounted on adjusting slides I! .and a turntable l8; Movement of the wheel head along the tworslides is, efiected by control levers l9 and 20 for normally positioning the grinding wheel in a desired relationship to the Work while the machine is being set up for 2 any operation. Normally, during operation, th grinding wheel head is stationary. The grinding wheel 13 is rotatably supported, as shown, on a slide plate 2| which can be moved up and down on vertical guides 22 by any suitable drive mechanlsm.

A work viewing means 24 is carried by a beam 25 on the upper end of a pedestal 26 that extends from the base Ill. The work viewing means has a fixed line of sight which extends generally downwardly towards the edge of the grinding Wheel. As shown, the work viewing means is a microscope having an eye piece 2'! and having a line of sight shown at 28 in Fig. 3. When the machine is properly set up, the effective grinding edge of the grinding wheel [3 is in exact correspondence with the line of sight 28, the wheel head I2 being adjusted manually along its slides until this is the case. p

The work table H is preferably arranged on a slide 30, these two parts having cooperating guide surfaces, preferably with anti-friction rolls or balls 3| between them so that free movement of the Work table can take place on the slide 3!] in a direction towards and from th grinding wheel. The slide 30 is similarly mounted on a plate 32 by means of anti-friction rollers 33 so that the slide 30' is freely movable ina direction generally parallel tothe grinding wheel axis and at right angles to the direction the table II can move on slide 30. The plate 32 is preferabl mounted for vertical adjustment by any-suitable means on the fixed standard 34 vertical adjustment given by rotating the hand wheel 35. It

will be apparent that the work table is held against rotating, but is freely movable in two directions at right angles to one anotherso that any desired horizontal movement of the work table can take place.

The workpiece to be ground is represented at 35. It will be understood that the workpiec may take any one of a great variety of shapes. Suitable clamping means 3! hold the workpiece in fixed position on a work support 38. This work support 38 is guided'for horizontal movement in a direction generally parallel to the grinding wheel axis on a slide 39. Transverse adjustment of the work support on the slide 39 is effected by a hand lever 40. The slide 33' is horizontally adjustable in a direction towards and from the grinding wheel on the work table II, by operating the hand lever 42. Thus it will be understood that the Work can be moved in any direction, for setup purposes, on the work table H.

The work table I I is automatically moved to give proper motion to the work during the grinding operation. This movement of the work table is produced, on a greatly reduced scale, in accordance with the movements of a stylus or follower 43 which is adapted to follow the enlarged contour on the board IS. The stylus or follower 43 is provided at the end of a long arm 44 of a pantograph including parallel links 45 and 46 and an arm 41 which is parallel to the long arm 44. The ends of the links 45 and 46 are pivotally connected to the arm 44 and the link 46 is pivotally connected to the arm 41, as will be under is another eccentric bushing 49 which supports J the arm 41. The eccentric hole within the bushing 49 slidably carries a rigid rod 50. The eccentric bushings are so related that the axis of the rod 50 moves in exact correspondence but on a greatly reduced scale as compared to the movements of the follower 43. The lower end of the rod 58 extendsinto a socket or hole in the work table ll. As the follower is moved, the work table II will thus partake of corresponding movements on a reduced scale. ment of the rod 50 within the eccentric passage in the bushing 49 can take place to accommodate the raising and lowering movements of the plate 32 during setup conditions.

It will now be apparent that the construction permits the workpiece 35 to be placed in position and adjusted by operating the hand levers 40 and 42 so that some reference point on the workpiece can be placed exactly in line with the line of sight 28 of the microscope when the follower 43 is at a starting position on the contour or drawing on the board I6. The grinding wheel can be adjusted so as to move until its grinding point comes into the line of sight. When the cross hairs of the microscope are exactly centered on the grinding wheel no further adjustment of the grinding wheel need take place until wear occurs on the wheel as evidenced by the retreat of the grinding wheel periphery from the cross hairs of the microscope. Until this wheel wear occurs, however, the operator merely causes the follower 43 to move slowly along the drawing or formed contour on the drawing board,

and this automatically adjusts the position of the work table and moves the work in the proper directions and to the proper degree so that the contour is reproduced, on a reduced scale, on the workpiece. Occasionally the operator may look into the microscope to make sure the grinding wheel has its periphery or effective cutting portion exactly in correspondence with the cross hairs. Eventually, due to gradual wearing down of the grinding wheel, he will see that the grinding wheel has retreated from the cross hairs. Under such conditions he merely need adjust the handle is to move the grinding wheel towards the work and bring the periphery of the grinding wheel back into exact correspondence with the line of sight of the microscope.

Under some conditions it might be impractical to grind the entire face of a workpiece by the same grinding wheel, but under those conditions a portion of the face of the workpiece can be ground, the grinding wheel then backed oil and removed and a new grinding wheel with the Vertical moveproper contour mounted in place. This grinding wheel is then moved until its effective grinding portions are exactly in correspondence with the line of sight of the microscope, and the grind ing operation is continued by moving the work through the pantograph system.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus.

and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1; A grinding machine comprising a base, a normally stationary grinding wheel head having a rotatable grinding wheel, a work table, a work support on said table, means for manually adjusting the work support with respect to said table, a plurality of slides arranged at right angle to one another and mounting said table on said base for free movement in a plurality of predetermined directions, means on said base for car? rying an enlarged contour of the part to ground, a follower for following the enlarged contour, a pantograph operably interconnecting the follower to the work table to automatically 1 move the work table on a reduced scale in ac-:

move the point of grinding contact of the grind ing wheel on the work to compensate for wheel wear, which is shown by the viewing device.

2. A grinding machine comprising a base, a normally stationary grinding wheel head having a rotatable grinding wheel, a work table, a work support on said table, means for manually adjusting the work support with respect to said table, a plurality of slides arranged at right angles to one another and mounting said table on said base for free movement in different directions at right angles to one another, means on said base for carrying an enlarged contour of the part to be ground, a follower for following the enlarged contour, an arm on said base,

a post movably carried by said arm and connected to said work table, a pantograph'open ably interconnecting the follower to said post to automatically move the work table on a reduced scale in accordance with the movement of the follower, a microscope carried by said arm and having a fixed lineof sight directed towards the grinding wheel and towards the workpiece, and means for manually adjusting said wheel head on said base to move the grinding point of the grinding wheel exactly to the line of sight of the microscope as wheel wear, shown by the microscope, occurs.

HOWARDE. BEAMS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 989,636 Pierpont Apr. 18, 1911 r 2,384,527 Blesi Sept. 11,1945