US2208892A

US2208892A - Hammer for mills

Info

Publication number: US2208892A
Application number: US262499A
Authority: US
Inventors: Bukacek Anton
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-03-17
Filing date: 1939-03-17
Publication date: 1940-07-23
Anticipated expiration: 1957-07-23

Description

July 1940- A. BUKACEK 2,208,892

HAMMER FOR MILLS Filed March 17, 1939 A TTORNEYS.

Patented July 23, 1940 UNITED STATES.

ENT OFFICE 1 Claim.

This invention relates to hammers designed primarily for use in connection with hammer mills.

Heretofore it has been the practice to form the hammers out of large sections of metal of sufficient hardness to meet the requirements and, in the event of wear or breakage, it has been necessary to replace the entire hammer.

An object of the present invention is to provide a hammer the main portion of which can be made of relatively soft metal while the striking surface or head of the hammer can be formed of a hard metal readily replaceable for the purpose of making repairs or replacements and requiring no special means for fastening the head to the hammer.

With the foregoing and other objects in View which will appear as the description proceeds, the invention consists of certain novel details of 20 construction and combinations of parts hereinafter more fully described and pointed out in the claim, it being understood that changes maybe made in the construction and arrangement of parts without departing from the spirit of the 25 invention as claimed.

In the accompanying drawing the preferred form of the invention has been shown.

In said drawing:

Figure 1 is a section through a portion of the 30 hammer mill provided with the present improvement.

Figure 2 is an enlarged side elevation of a hammer.

Figure 3 is a rear elevation thereof.

35 Figure 4. is a section on line 4-4, Figure 3.

It is to be understood that any type of cylinder or concave can be used in connection with the hammer constituting the present invention and no attempt has been made to illustrate these 40 parts in detail. In Figure 1 one form of an apertured concave has been indicated at A, a rotary shaft has been indicated at B and a series of disks C is connected to the shaft so as to rotate therewith. These disks C are provided with 45 the hammers indicated generally at H and which are pivotally mounted on rods I so as to swing freely relative .to disks C and shaft B.

In the present case each of the hammers is formed of a flat steel strip l which can be suit- 50 ably proportioned and is folded to provide steel straps 2 which merge at one end to form a substantially cylindrical loop 3. An opening 4 is extended through the hammer adjacent to that end remote from loop or sleeve 3 and is adapted to receive the pivot pin I whereby a free swinging movement of the hammer is possible. The straps are joined by welding or by any other means desired.

The hammer head comprises a cylindrical pin 5 5 provided at one end with a head 6 preferably rectangular. This head can be made entirely of hard steel or its. face only can be hardened or formed with a hardened layer I joined thereto.

Pin or stem 5 can be. inserted readily into the 10 sleeve 3 and it is adapted to so place it that the head 5 will be at the advancing end of the pin when the hammer is rotated about the axis of shaft B.

Any desired number of hammers can be used, according to the type of mill employed and the size thereof. In every case the hammer mill shaft B rotates at a high speed and this speed is sufiicient to hold the arms I-I normally extended substantially radially by centrifugal force and obviously the rotation of the hammer in the direction of the arrow shown in Figure 1 will tend I to maintain the pin 5 firmly seated in the sleeve 3. As the outer edges of the heads 6 come into contact with material to be broken up thereby, they will be free to yield backwardly a required amount until resistance is overcome, this yielding action being due to the fact that the arms carrying the heads are pivotally mounted.

Obviously any one of the heads can readily be removed simply by sliding its pin or stem 5 out of its sleeve 3. By making thehead rectangular the same can be rotated about the longitudinal axis of the pin or stem 5 so as to bring anyone of the edges of the head into active or striking position.

What is claimed is:

In a hammer mill a rotatable shaft, a member rotatable with and mounted to swing relative to the shaft, said member comprising a metal strip folded to provide a cylindrical loop at one end and parallel arms extending from the loop, said arms being joined adjacent to their ends, and apertures at a point remote from the loop, an angular head having a flat face bearing against the loop at one end, a cylindrical stem extending from the center of the head and detachably and frictionally seated within the loop, said stem and head being adjustable angularly about the longitudinal axis of the stem to bring any edge of the head to working position, the advancing face of the head being harder than the remainder of the head.

ANTON BUKACEK.