US1044261A

US1044261A - Artificial grindstone.

Info

Publication number: US1044261A
Application number: US69649812A
Authority: US
Inventors: Otto Schmidt
Original assignee: OTTO SCHMIDT S PATENT HERCULESSTEINE M B H GES
Current assignee: Gesellschaft Otto Schmidt's Patent Herculessteinem B H; OTTO SCHMIDT S PATENT HERCULESSTEINE M B H GES
Priority date: 1912-05-10
Filing date: 1912-05-10
Publication date: 1912-11-12
Anticipated expiration: 1929-11-12

Description

0. SCHMIDT.

ARTIFICIAL GRINDSTONE.

APPLICATION Hum 11u-1o, 1912.

Patented Nov. 12 I1912.

@vih/Leone o :j

UNITED STATES PATENT oEEIcE.

OTTO SCHMIDT, 0F DRESDEN, GERMANY, ASSIGNOB T0 GSEDISCHAFT OTTO SCHMIDTS PATENT HEBGULESSTEINE l. B. I., OI-DEESDEN, GmN'I, .A OURPQRATIGN A0F GERMANY.

Eminem GBINDSTQNE.

Specication of Lette-rs Patent. i Patented-NOV. 12, 1912..

Application led May 10, 1912. Serial No. 686,498. v

more, and as the modern wood-pulp factories commenced the use of grinding machines which required considerably greater power, a highly increased pressure and augmented velocities, the grind-stones which were .made from the naturalstone did not meet these requirements, and it. was therefore necessary to make grind-stones from artificial material. Though these artificial grind-stones responded in a greater degree to the present requirements as to` the capability of resistance than the natural stone,

they failed in some respects to fully come up to the requirements, and it was therefore 'necessary to improve the same still further.

The object of this invention is to ysupply an artificial grind-stone which has all the properties of th`natural stone and in which the exterior portion or ring is made of a mixture of sand and cement and an interior portion is made of ring-shaped core, said exterior portion and core being connected by a suitable binding substance interposed between the same.

In theaccompanying drawings, Figure l represents a vertical transverse section d throughfthe improved grind-stone, and Fig..

2 a plan-view of Fig. 1.

Similar letters of reference indicate the same parts in the different gures of the drawing.

Referring to the drawing, a represents a cylindrical ring which is formed of a mixture of sand and a binding material, such as cement' which corresponds in hardness to the grain of natural sandstone. The grinding ring a is reinforced by metallic rings al near its inner portion. The interior ringshaped space inclosed by the cylindrical grinding ring a is filled up after it has properly hardened with a ring-shaped core b of concrete which serves for the reception of the plaster by which the stone is mounted on the shaft, that imparts the rotatory motion to the grind-stone. Experience with artificial grind-stones has shown, however, that by the introduction of the concrete mass into the grinding ring and the tamping of this mass into the same, tensions are produced in the ring which exert a weakening action on the grinding ring and tend to induce cracks or fissures in the same. further objection is that the hardening of the concrete which has been tamped into the grinding ring takes up a considerable length of time so that the artificialgrindstone cannotbe placed into use. Both these l objections are overcome by making their-ing- The filling the space 'which is left between the same and the core with suitable binding substance c that is introduced between their adjacent surfaces so'that an intimate connection of the core with the cylindrical ring is obtained and both parts form practically one `entire mass. As the interposed binding material has but little volume, the advantage is obtained that the binding and hardening process takes place much quicker, as is the case with the heavy and thick mass of concrete heretofore used for the core. Furthermore, the stresses which heretofore have acted unfavorably on the grinding ring are entirely obviated so that an artificial grind stone is obtained that meets as 'regards stability and permanency the most rigid requirements for such a stone.

Iclaim:

An artiicial'grind-stone for mechanical wood-pulp, comprising an exterior cylinl g l 1,044,261

drical grindin ring, an interior hollow corev of concrete a apted to be placed on the shaft, and an intermediate layer of a binding substance interposed between the grind- 5 ing ring and the lnterior core for uniting the same.

In testimony, that I claim the foregoing as my invention, I have signed my name in lpresence of two subscribing'witnesses.

OTTO SCHMIDT.

Witnesses ALFRED DIX HEINRICH ARLICH.