US2274502A - Mulling apparatus - Google Patents

Description

Feb. 24, 1942. w E PIPER 2,274,502

MULLING APPARATUS Filed Feb. 13, 1939 2 Sheets-Sheet 1 Feb. 24, 1942. w. F. PIPER MULLING APPRATUS Filed Feb. 13, 1939 2 Sheets-Sheet IIIIIHHHIIH..

Inf/@Mr Patented Feb. 24, 1942 f l, UNITED STATES PATE-NT OFFICE I 2,274,502

l MULLING APPARATUS v. Walter F.'Piper, Oak Park, Ill., assigner to The Beardsley & Piper Company, Chicago, lll., a

corporation of Illinois Application February 13, 1939, Serial No. 256,096

2 Claims.

The present invention relates generally to apparatus for mulling granular material. More particularly the invention relates to that type of mulling apparatus which is especially designed for use in a vfoundry or like establishment in connection with the mulling or conditioning of molding sand and as the main or essential parts thereof comprises (1) a frame structure; (2) a sand retaining receptacle which embodies an annular side wall and is rotatably supported; (3) a plurality of rotary mulling elements which are disposed in the receptacle adjacent to the side wall and are adapted during rotation or drive y of the receptacle to squeeze the sand against the inner face of the side wall; and (4) an electric motor which is mounted on the frame structure vand is connected through the medium of a speed reducing unit to rotate the receptacle.

One object ofthe invention is to provide a mulling apparatus of this type in which the vreceptacle is mountedfor rotation about a hori zontal axis and Ahas one end thereof open for the entry and discharge of batches of sand 'and its other end closed, and the motor and speed rev ducing unit which constitute 'the driving medium.- for the lreceptacle are mounted on the supporting structure adjacent to, and outwardly of, the end wall and as a result they are readily accessible for repair, replacement or inspection purposes, and in addition, are not likely to have anyof, the sand to be mulled or the mulled sand come in contact therewith.

' Another object of the invention is to provide a sandl mulling apparatus of the type and character lunder consideration in which the mulling elements are two in number and of wheel type and are mounted and urged outwards in a novel manner invorder to effect4 eiilcient mulling of the sandbetweenthem and the side wall of the A, receptacle. v

y I .Af.urther c bjectof the invention is to provide amulling apparatus oi the last mentioned -:type and character in which the wheel type mull- `:ingelements are "positioned above the axis of flthelreceptacle with theresult that they tend `partiallytofsupport "the receptacle and thus reduce 'he-'f'il/clfy on "the main receptacle 'supporting d lmulling apparatus which is sim- `costly than, and is generally an upon, previously designed sand y ratu's" including that forming the ubjct in tteif "'oqf anfapplication for United tates Lette rsf'Eat'e'rit iiled by me September 19, "6; serial r'rdj 101,555. u k

lier"T yIgijfects' oitheI invention and the various "tages 'rther' `object of the invention is kto*` fandn characteristics of the present iidmullig apparatus'will'` be apparent from a' '60 consideration of the following detailed description.

The invention consists in the several novel features which 'are hereinafter set forth and tacle; and

Figure l3 is a vertical transverse sectional view taken on the line 3 3 of Figure 1 and showing in its operative position the scraper which constitutes, apart oi the means for discharging the mulled sand from the receptacle.

The apparatus which is shown in the drawings constitute. the preferred` embodiment of the invention. It is designed primarily for use in a foundry or like establishment in connection with.` the mulling or conditioning of molding sand and comprises a frame structure 4, a sand holding or retaining 'receptacle 5, a pair of mulling elements 6, and an electric motor l.

The frame structure 4 is designed or adapted to rest on the floor of the foundry in which the apparatus is used and serves as the main supporting medium. for the operating parts of the apparatus. It is rectangular and comprises a pair of horizontally extending laterally spaced parallel side beams 8, and a transversely extend- `ing horizontally positioned cross beam 9.

The cross beam` 9 extends between andV is welded or otherwise iixedly secured to the central portions of the side beams and serves to cross-connect and hold inl laterally spaced relation the side beams.. In addition to the side beams 8 and the cross beam 9, the frame structure 4 comprises a I3 and is suitably connected to the side beams 8 of the' frame structure.

The unit I3 together with the electric motor 1 constitutes the driving means for the receptacle 5 and comprises a casing I4, a drive shaft I5, and a horizontallyextending driven shaft I6. The drive shaft I5 is aligned with the armature shaft of the electric motor and is connected vto such shaft by a coupling I1. The driven shaft I3 is journaled in a bearing I8 in the casing I4 and is connected by suitable gearing in the casing for low speed drive from the shaft I5. The outer end of the driven shaft I6 projects an appreciable distance beyond the bearing I8 of the casing and is disposed over the central portion of the frame structure 4. The framework I2 is located over the ends of the side beams 8 which are remote from the electric motor 1 and the speed reducting unit I3. Itconsists of uprights and cross-pieces which are suitably secured together so that the framework as a'whole is of rigid design. f

The receptacle is disposed between the frame work I2 and the speed reducing unit I3 and is adapted to be charged with a batch of sand to be mulled by way of a chute I9. It is generally cylindrical in contour or design and consists of an annular side wall 20 and a circular end wall 2|. The side wall 20 is of uniform diameter from one end thereof to the other and is adapted to have the sand to be mulled squeezed against the inner face thereof by the mulling elements 6. The end wall 2I is joined to and formed integrally with one end of the side wall 20 and has in the central portion thereof a hub 22. The latter is mounted on the projecting end of the driven shaft I6 of the speed reducing unit I3 and is keyed to such shaft so that when the unit 1s driven by the electric motor 1 the receptacle 5 is in turn driven or rotated about a central horizontal axis. An inwardly extending ring-shaped flange 23 is formed integrally with the other end of the side wall 20 of the receptacle and denes a circular opening 24 for the entry and discharge of the sand. The chute I9 is carried by the framework I2 of the supporting structure 4, as shown in Figure 1, and is adapted to deliver a batch of .sand to be mulled into the receptacle via the opening 24. The lower discharge end of the chute I9 extends through the opening 24 and terminates above the lower portion of the receptacle side wall. When the receptacle is driven by the motor 1 through the medium of the speed reducing unit I3, the sand adheres to the side wall of the receptacle as a result of the fact that it is subjected to the action of centrifugal force. The motor and speedreducing unit are of such design that they drive the receptacle at a suillcient speed to maintain the desired adherence of the sand to the receptacle side wall. If thevreceptacle is four feet in diameter it is rotated at forty or more revolutions per minute.

The two mulling elements 6 are in the form of wheels, and, as shown in Figures 2 and 3, are disposed one opposite the other in the upper portion of the receptacle 5. They are mounted rotatably on stub shafts 25 and operate during drive or rotation of the receptacle to effect mulling of the sand by squeezing it against the inner face of the side wall 29. The shafts 25 are positioned in parallel relation and project through the circular opening 24 in the flange 23. The outer ends of the shafts are fixed within cylindrical sockets 26 in the central portions of a pair of vertically extending arms 21. The lower ends of the arms are pivotally connected by pins 21*I to a pair of brackets 23 on, the top anges of the cross beam 9 of the frame structure 4 so that the arms together with the wheel-type mulling elements are free to swing inwards and outwards with respect to the receptacle side wall. Acompression spring 29 extends between the upper ends of the arms 21 and serves to urge the arms apart so that the mulling elements in turn are urged outwards against the receptacle side wall for mulling purposes.. A rod 30l extends through holes 3l -in the upper ends of the arms 21 and prevents lateral displacement of the spring 29. Nuts 32 are mounted on the outer ends of the rod 30 and limit outward swinging movement of opening 24 in the ring-shaped ange 23 and are positioned in front of the wheel type mulling elements 6, as shown in Figure 3. When the apparatus is in operation, the sand after being squeezed against the side wall of the receptacle by one of the mulling elements encounters the scraper in front of the other element and is scraped from the receptacle side wall and directed inwardly in an aerated manner into contact with the other element. After being subjected to the action of the other mulling element. the sand encounters the other scraper and is scraped by the latter from the receptacle side wall and directed inwardly in an aerated manner towards the other mulling element. AAs a result of successive squeezing and aeration of the sand by the joint action of the mulling elements and scrapers, the sand is eifectively mulled in the receptacle. The inner faces of the scrapers are so angled or positioned that they direct the scraped sand inwardly at an abrupt angle into contact with the mulling elementsl 6.

In addition to the supporting structure 4, the receptacle 5, andthe other hereinbefore described parts, the apparatus comprises means for discharging the sand from thereceptacle after mulling thereof. ,Such means comprises a discharge chute 34 and a scraper type deflector 35. The discharge chute 34 is positioned alongside of the discharge end of the chute I9, as showny in Figure 2, and extends downwardly from the upper portion of the interior of the receptacle through the opening 24 in the iiange 23. The upper end of the chute 24 is infundibular or funnel-shaped and is positioned between the wheeltype mulling elements 6. The lower end of the chute projects into the space between the side beams 8 of the frame structure 4 and is adapted to direct the mulled sand into a hopper or onto a conveyor. The deflector 35 is positioned over the upper end of the chute 34 and is pivotally connected by a pin 36 te a bracket 31 on the framework I2 so that it may be swung back and forth between an operative position wherein the leading edge thereof is disposed adjacent to the inner face of the receptacle side wall and an inoperative position wherein it is beneath the top portion of the side wall and for the most part within the upper cnd of the discharge chute 34 as shown by dotted lines in Figure I. When the deilector is in its operative position, the leading edge thereof serves to scrape the sand from the side wall of the receptacle as the latterrevolves and the trailing or lower portion of the deiiector opertance betwe'en the side wall 2| and the flange 23 and as a result operates to eect discharge of the entire mass or batch of sand within the receptacle during one revolution of the latter. The lever 38 is pivotally connected to a bracket v393 on the framework l2 of the supporting structure 4 and is connected to the scraper type deector 35 of the discharge means by means of an arm 40 and a link 4|.` The arm 40 is xed to and depends from the pin 36, as shown in Figure 1, and the link 4| extends between and is pivotally connected at its ends to the central portion of the lever 38 and the lower end of the arm 40. When the lever 38 is swung in one direction the deflector 35 is swung into its operative position and when the lever 38 is swung in the opposite direction the deflector is caused to swing or move downwards into its inoperative position within the upper end of the discharge chute 34. A retractible dog 42 and a gear segmeni; 43 serve releasably to lock the lever 38 in its various positions.

When it is desired to operate the apparatus, the motor L is rst'started so as to eiect rotation or drive of the cylindrical receptacle 5.

Thereafter the batch of sand to be mulled is introduced into the receptacle by delivering it into the upper end of the chute |9. Such chute,

l as hereinbefore described, operates to deliver or direct the sand into the receptacle. As the sand is delivered into the receptacle it comes in contact and revolves with the side wall 20. As the sand passes the wheel type mulling elements 6 it is squeezed against the side wall by the elements and the` desired mulling is eiected. If bonding material is mixed with the sand it becomes uniformly distributed over the various grains of sand asthe esult of the squeezing sand to -be mulled or the mulled sand come in contact therewith. An advantage of having the receptacle mounted on a horizontal axis and the speed reducing unit I3 positioned adjacent to and outwardly of the closed end of th'e receptacle is that the gearing of the unit need not be of the b'evel gear variety. The apparatus is further characterizedby the'fact that the discharge of the mulled sand is substantially instantaneous in that it takes place during a single revolution of the receptacle. Because the wheel type mulling elements 6 are positioned above the center or axis of the receptacle and are urged outwards by the compression spring 29 the load on the bearing I8 of thecasing of the speed reducing unit |3 is materially lessened.

Whereas the apparatus has been described as being primarily or particularly designed for use in a foundry in connection with the mulling of molding sand, it is to be understood that it may be used for the conditioning or mulling of other granular material. It is also to be understood that the invention is not to be restricted to the details set forth, since these may be modified within the scope of the appended claims, without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent is: v

1. A mulling apparatus comprising in combination av frame structure, a receptacle for the material to be mulled supported by a sh'aft and bearing to rotate on a iixed substantially horizontal axis and embodying an annular side wall concentrically arranged with respect to said axis 'i and having one end thereof open and its other end closed and connected to said shaft, means for rotating the receptacle, a pair of oppositely disposed mulling elements positioned adjacent to the inner face of the side wall and for the most part above the axis of rotation of the receptacle and having frame-structure-carried supporting means therefor whereby they are permitted to move toward and away from said side wall, and

and mulling action of the elements 8. During drive of the receptacle the scrapers 33 in front.

of the mulling elements operate as hereinbefore described to scrape the squeezed sand from the receptacle side wall and to throw or direct it inwards in an aerated manner into contact with th mulling element 8. When it is desired to discharge the sand from the receptacle after mulling of the sand to the proper or desired extent, the lever 38 is swung so as to swing or shift upwardly the scraper type deilector 35 into its operative position. As soon as the deilector reaches such' position it operates to scrape the sand from the side wall of the receptacle and to direct it into the upper end ofthe discharge chute 34.

The herein described mulling apparatusv con sists of but a small number of parts and hence may be manufactured at a low and reasonable cost. Itis extremely eiiicient and effective as far as the mulling of molding sand is concerned and is characterized by the .fact that the electric motor 1 and the speed reducing unit I3 are.

pressure means for urging the elements outwards against said side wall so as-to cause them to squeeze the material against th'e'side wall for mulling purposes during rotation of the receptacle and also assist in supporting the receptacle.

2; A mulling apparatuscomprising in combination a frame structure, a receptacle for the material to be mulled supported -by a shaft and bearing to rotate on a fixed substantially horizontal axis and embodying an annular side wall concentrically arranged with respect to said axis and having one end thereof open,`means for rotating the receptacle, a pair of oppositely disposed rotary mulling elements positioned adjacent to the inner face of .the side wall and above the receptacle axis of rotation and having framestructure-carried supporting means therefor wherebyfthey are permitted to move toward and.

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