US1154051A - Concrete-mixer. - Google Patents

Description

1. S. OWENS.

CONCRETE MIXER. APPLICATION FILED' 11111.31, 1911.

Patented Sept. 21, 1915.

.oLuMulA PMNOGRAPH co.,WAsHxNOToN. D, c.

TNTTED STATES PATENT FFTCE.

JOI-IN SWITZER OWNS, OF LONDON, ENGLAND, .ASSIGNOR TO JOHN MALAN DE MENDOZA VER MEHR, 0F LONDON, ENGLAND.

CONCRETE-MIXER.

laminar.

Specification of Letters '.latentV Patented Sept. 21, 1915.

Application filed January 31, 1911. Serial No. 605,773.

To all whom it may concern Be it known that I, JOI-1N Swrrznn OWENS, a subject of the King of Great Britain, residing at London, inthe county of Middlesex, England, have invented new and useful Improvements in Concrete-lIixers, of which the following is a specification.

This invention has reference yto mixing machines for concrete, mortar. tar macadam and the like and has for its object to provide an improved mixing machine of the moving beater type in which arms or beaters revolve in a` normally fixed container or mixing vessel. One of the chief difficulties heretofore encountered in the practical operation of this type of machine when mixing hard granular materials has been the jamming of hard particles in the working parts of the apparatus with a consequent increased consumption of power in driving and w .ar and tear of the machine. This jamming occurs principally between the mixing blades and the inner surface of the mixing vessel.

Now the primary object which I have in view is to obviate this disadvantage by the construction hereinafter described.

With these ends in view the chief feature of my invention resides in pivotally connecting the mixing blades or beaters to the shaft by means of which they are rotated in such a manner that the pivots on'which they are hung are in advance of the points of thc blades in the direction of rotation to the end that any excessive pressure on the point of any of the blades due to jamming of hard particles will cause the point of said blade to move relative to its pivot and on the arc of a circle having its pivot as a center thus causing the point of the away from the inner surface of the mixing drum and so clearing the obstacle.`

The invention further comprises the details of construction and arrangement of parts all as more particularly hereinafter described and finally pointed out in the claim.

In order that my invention may be readily understood and will now proceed to describe the same fully for which purpose reference is to be had to the accompanying drawings in which:

Figure l represents a side elevation of a mixing machine constructed in accordance with my invention. Fig. 2 isa view `of the blade to be liftedV carried into practice I;

mixing drum one side or wall being removed in order to show the .arrangement and mounting of the blades or beaters there- 1n. Fig. 3 is a detail view of one of the blades or beaters and its mounting.

Referring to Fig. v1 the machine comprises a frame which may conveniently be constructed 0f angle irons a riveted or otherwise secured together to form a support for bearings ZJ in which is mounted to rotate a shaft c passing axially and freely through the drum d which is open at its upper part and is supported by trunnions engaging inthe shaft bearings b in such a manner that it may be inverted to discharge its contents when desired. For this purpose the d rum CZ is provided with a segmental rack e adapted to be engaged by a pinion f mounted on a spindle g operated by the handle 71. so that when this latter is turned in the direction of the arrow Fig. 1 the drum` CZ will be inverted so chuting its contents into a suitable receptacle placed. beneath it. In order that the drum may be prevented from swinging during the mixing operation I lprovide a stoppin arranged to slide freely in holes formed in the lugs of the bracket supporting the aforesaid pinion f so that it may be inserted between the teeth of the pinion to prevent its movement.

The mixing blades or beaters z' of which in the construction herein described and illustrated there are four are mounted within the drum (l upon the shaft c and as the construction and Vmounting of these mixing blades constitutes one of the essential features of the present invention I will therefore rdescribe their arrangement in considerable detail for which purpose Figs. 2 and 3 should now be refer-red to.

The shaft c is surrounded by a sleeve j rigidly secured to the shaft such as by means of set screws 7c. The sleeve j carries projecting lugs Z two for each blade z' and between eac'h pair of such lugs is pivoted at m and arm n to the opposite end of which the blade z' is secured. The arm n is formed with anabutment or projection o adapted to engage with Aa stop formedfby a web p cast between each pair of lugs Z the parts being so adjusted that in the normal position of the arm n as shown in Fig. 2 the point of the blade i will .be just vout Aof contact with the interior surface of the drum d. Mounted upon the pivot m is a spring q bearing upon the arm a thus holding it in operative position or the blades may be made especially heavy so as to cause them to be' kept in or nearly in Contact with the drum d during part of their revolution. The mixing blades a' which are preferably of steel are curved as shown in such amanner as to' deflect all material toward the'center of the drum during the mixing operation and also to scrape the whole internal surface ofthe drum clear when this latter is inverted as above described.

- It will thus be seen that I have provided a construction in which each of the mixing blades is rcsiliently suspended from the operating` sha-ft at apoint in advance of the point ofthe blade in the direction of rotation so that any excessive pressure upon the point of a blade due to jamming of hard particles between it and the drumfwill` cause the point of the blade to move on'the arc of a circle striiclrrrom the point of suspension vof the blade which being eccentric to the shaft and in advance of the point of the` bladewill cause said blade to be lifted clear ofthe obstacle. It will further be seen that the curvature given to the mixing blades will allow them to enter and pass through any material in the drum at an oblique angle thusy contributing to the more eflicient mixing of the material with aminimum expenditure of driving power.

Y In order that the material to be mixed may be' readily fed into the drum d I provide 5a tilting hopper a pivoted as at o2 (Fig. l) uponthe frame a, and having suitable counterweights a3 and a handle orvhan` dles a4 for operating the hopper by hand. With the hopper in the position shown in Fig.' l the necessary charge may be introduced therein said hopper being retained in its lowered position by the pivoted catch a5 which engages beneath a part of the .framing a. By releasing said catch a5 the hcpper may be tilted to shoot the charge into the drum d. Y

A'The' drumv d is preferably of semi-cylindrical form with coned ends, a shape which further facilitates the charge being deflected` toward the center of the drum; y

rIhe operation of an apparatus constructed in accordance with my invention is as follows The appropriate quantity of ma# terials to be `mixed having been introduced. intoy the mixing drum Z either by hand or-through the medium of the tilting hopper or chute or the fixed hopper, the fly wheel jz/ ,is rotated by means of its handle d 'thus driving shaft c upon which the. mixing blades i are -mounted as above described. Said bladesas they rotate with the shaft c enter and pass through the material within the ldrum at an oblique angle thus causing thorough intermixing of the ingredients and at the same time causing them to be constantly deflected toward the center of the drum. Should the blades during their rotation encounter any large stone or other' obstacle they will owing to the resilient eccentric mounting at once lift and so clear the obstacle. Vfhen mixing is 'complete in the machine shown in the drawings the handle 71. is operated .thus inverting the drum through pinion f and rack e so discharging its contents into a truck or the like arranged for `its reception. The blades z' during this 'operation will assist to scrape the interior .of the drum clean.V YThe drum may now be returned to its normal position and a fresh lcharge introduced.

' I have in the foregoing specication described my improved apparatus as being driven hand through the iiy wheel i/-but it vwill. of course be understood that the fly wheel may be replaced by fast and loose pulleys and the machine driven from any suit- Y able source of power.

" While I have described the preferred construction of parts and operation thereof I am'aware that numerous changes of con struction and operation may be made without departing from'the spirit and scope of the invention and I therefore do not wish to be Y understood as limiting myself by the positive terms employed in connection with the description excepting such as the state,

of the art may require.

- `What I claim and desire to secure by Letters Patent of the United States of America 1s:-

In a mixing machine the combination with a frame of a normally ixed mixing receptacle supported thereby, va revoluble shaft passing axially through said receptacle, a sleeve mounted on said shaft and constrained to rotate therewitlnradially projecting spaced apart lugs arranged in pairs upony said sleeve, a stop-web formed between said lugs, arms each havingapivotal support betweensaid lugs-at one side of the web, an angula-rly disposed abutment formed at one end of said arms and projecting therefrom so'as to contact with said web, mixing.

Coplslof Vthis patent inay ybe .obtained forve cents each'i by addressing therf, Commissioner of Patents, Washington, IJ. C.

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