US2213665A - Device for dressing screw-threadgrinding disks - Google Patents

Description

P 3, 1940- H. BRENDEL El" AL 2,213,665

DEVICE FOR DRESSING SCREW-THREAD-GRINDING DISKS Filed April 2', 195a Patented Sept. 3, 1940 DEVICE FOR GRIND I Hans Brendel and Erich Buchhols, Hamburg- Wandsbek, Germany,

Schaurte, Nenss-on-the-Rhine, corporation of Germany 2, 1 938, Serial N April 3, 1937 Application April In Germany 4 Claims.

This invention relates to a device for dressing disks for grinding screw-threads.

Heretoforain the grinding of screw-threads,

it has been practically impossible to obtain microscopic trueness in the grinding disk. This was fundamentally true because in trimming the grinding disk withgrinding tools, primarily diamond cutters, the trimming was done by putting the cutters against the grinding disk and cutting w one side first, and then cutting the opposing side. In this manner, the grinding disk resulting was untrue and consequently unfit for precision work.

Other means have been suggested, but none have been successful, since the pressures of the grinding and profile-finishing tools were unequal on opposing sides of the grinding disk per se.

The present invention contemplates utilizing an apparatus wherein the diamond-trimming -finishing tools afford equal and pposite pressures on the respective grinding surfaces of the disk to be dressed.

It is an object of this invention to provide grinding disk trimming means wherein the pres- 35 sures of the disk trimmers per se will be equal and opposite againstthe grinding disk.

A further object dressing grinding disks per se by causing a series of tools to engage opposite sides of the grinding surfaces of a grindingdisk while utilizing equal tool pressures simultaneously on opposite sides of the working flanks of a grinding disk.

Further and other objectsmay become apparent to those skilled in the art from a perusal 8 of the drawing and specification herewith.

Inthe drawing: Fig. 1 shows diagrammatically a dressing device for a screw-thread-grinding disk;

Fig. 2 shows subst 40 in Fig. 1, but the arrangement thereof is different to present special working conditions; and

- trimming of the whe is to provide a device for upon the pressures antialiy the same parts as and other round thread Fig. 3 shows in section a device for effecting the external roundings of the grinding disk for 45 the production of round thread profiles.

similar characters of reference indicate cor-. responding parts throughout the various views.

Referring more, particularly to Fig. l, the dressing oi the flanks of a profile grinding disk 50 by means of simultaneous longitudinally moving tools is carried out. The diamond carriers d provided with the diamonds d' are adapted to be greciprocated in their holders in' the direction of the arrows H; In the embodiment illustrated, the flanks a v work.

nnessmo scnEw-rnnmnmo msxs .assigno'rs to Bauer & Germany, a

and b of the disks are shouldered, providing the transition stages o. It will be seen from Fig. 2 that the disk I0 is engaged on one side by diamonds d carried by the tool carrier H. The diamonds d' of the tool carrier II are moved 5 out of engagement with the disk it. The resultant pressure therefore causes the displacement angle it between the true center shown as dashdot line ii,-,and the resultant center shown by dash-dot line It caused by the pressure of the tools of the tool carrier is. 1' Q It. will therefore be seen that tol produce the el It by the putters d of essure of necessity must be ible to avoid the disk from M to substantially a line tool carrier M, the pr such thatit is imposs moving from the line approximating line It.

In Fig. 1 it is seen thatthe tool carriers d have the individual components l2 and i3, which com-' ponents may move to and fro along the flanks a and b of the grinding disk, and said to and fro movement may be either in the same general direction at one time, or they'may be moving in opposite directions at substantially the same time. Whether or not the tool carriers 12 and as move in the same general direction, or whether one moves in one direction while the other moves in an opposite direction, is entirely dependent presented by the diamonds to the surfaces. at and b of the grinding disk. The displacement caused by the movement of the tool carriers i2 and I3 in the directions ofthe ar= rows ii is generally quite small as long as the diamond cutters on opposite sides of the disk are engaging the disk simultaneously, there will be substantially an absolute elimination of the angle h. 1

Fig. 3 shows how the end faces care used for the production or dressing of the concave, rounding or curved working face e on Whltworth profiles. There is also shown the mode of operation of a disc or roller f of steel, hard metal or the like, which produces the convex rounding surfaces e simultaneously with the rounding of the core-forming portion or apex g on the grinding disk. The parts c and 0', shown dotted, indicate the contour of the wheel l0 after trimming. with the diamond and before engagement with the roller or tool 1 which is in fact a profile-finishing tool which eliminates the necessity of forming the profile with diamond cutters. This is quite essential on grinding disks where the profile is extremely minute and is used for microscopic precision A The roller or tool I moves at right angles to the axis of the grinding disk, so that'the pres sures on the surfaces 0, which surfaces are disposed on opposite sides of the grinding disk, will receive equal pressure when the tool 1 is urged against the grinding disk In in properalignment.

It will therefore be seen that in both the diamond trimming and proflle-flnishingoperation's of the complete dressing of the grinding wheel, the pressures on opposing flanks of the grinding surfaces are substantially equal and opposite throughout all dressing operations.

What we claim as new,'and desire to secure by Letters Patent of the UnitedStates is:

v the point in a higher plane than the other dial. A device for dressing screw-threaded grinding disks, comprising two rigid carriers, each supporting two diamonds, the carriers being disposed so that the diamonds move in planes each parallel to the flank surfaces of the disk to be dressed, said diamonds being disposed in difierent planes, the diamonds for the flanks forming the point being in ahigher plane than the other diamonds in that the pointflanks are set inwardly in respect to the other flanks, means for moving said two carriers against both flanks at the same time, and means limiting the active movement of one diamond of each carrier by the'other.

grinding disks, comprising two rigid carriers, each supporting two diamonds, the carriers being disposed so thatthe diamonds move in planes each parallel tothe flank surfaces of the disc to be dressed, said diamonds being disposed in different planes, the diamonds for the flanks forming to each other, and a proflle roller for simultane- I ously further dressing the disk at its point for convexly rounding the same, and at its shoulders for concavely rounding the same.

3. In a device for dressing screw-threaded t grinding disks, comprising two rigid carriers, each supporting two diamonds, the'carriers being disposed so that the diamonds may move in planes parallel to the proposed flank surfaces of the 7 disk to be trimmedfsaid diamonds being disposed in different planes, the diamonds for the flanks forming the point in a higher plane than'the other diamonds in that the point flanks are set V 4. In a device for dressing screw-threaded.

grinding disks, comprising two rigid carriers, each supporting two diamonds, the carriers being disposed so that the diamonds may move in planes parallel to the proposed flank surfaces of the disk to be trimmed, said diamonds being disposed in different planes, the diamonds for the flanks forming the point in a higher plane than the other diamonds in that the point flanks are set inwardly in respect to the other flanks, and means limiting the active movement of one diamond of each carrier by the other diamond of the same carrier, said means including a shoulder formed between the flanks, means to permit said two carriers to impinge opposing flanks of the grinding disk simultaneously while both c'arriers are moving in the same general direction, and core-forming, profile-finishing means moving at from the axis of the grinding disk to engage said disk shoulders formed between the flanks on each side of said'disk to make said flanks concave incontour. 1

HANS BRENDEL. an on BUCHHOLZ.

Images