US3811812A

US3811812A - Mill for manufacture of plaster concrete articles

Info

Publication number: US3811812A
Application number: US00250169A
Authority: US
Inventors: V Borisevich; A Fiskin; I Samsonov; A Savushkin; N Zemtsov; A Birger
Original assignee: SPETSIALNOE KONSTRUKTORSKOE BJURO PO KOMPLEXNOI RAZRABOTKE TEKHNOLOGICHESKIKH PROTSESSOV IZGOTOVLENIA ZHELEZOBETONNYKH IZDELY METODOM NEPRERYVNOGO PROKATA SKB "PROKATDETAL"
Current assignee: SPETSIALNOE KONSTRUKTORSKOE BJURO PO KOMPLEXNOI RAZRABOTKE TEKHNOLOGICHESKIKH PROTSESSOV IZGOTOVLENIA ZHELEZOBETONNYKH IZDELY METODOM NEPRERYVNOGO PROKATA SKB "PROKATDETAL"
Priority date: 1972-05-04
Filing date: 1972-05-04
Publication date: 1974-05-21
Anticipated expiration: 1991-05-21

Abstract

A mill is disclosed which is provided with a device for feeding plaster concrete wastes back to a concrete mixer, said device comprising means for receiving and crushing the wastes, as well as means for conveying said wastes back to the concrete mixer.

Description

111111611 States Patent 1191 Birger et al.

[ MILL FOR MANUFACTURE OF PLASTER CONCRETE ARTICLES [76] Inventors Abram Isaakovich Birger, Prospekt Mira, 184, korpus 2, kv. 167; Alexandr Mikhailovich Fiskin, Prospekt Mira, 184, korpus 2, kv. 21 1; Ivan Sergeevich Samsonov, Zuezdny bulvar, 5, kv. 23; Anatoly Alexandrovich Savushkin, 2 Novo-Ostankinskaya ulitsa, 14, kv. 5; Nikolai Nikolaevich Zemtsov, Prospekt Mira, 184, korpus 2, kv. 164; Vitaly Arkadievich Borisevich, Zvezdny bulvar, 5, kv. 174, all of Moscow, U.S.S.R. I

Filed: May 4, 1972 [21 Appl. No. 250,169 g 52 US. Cl ..425/217,425/218,425/220, 1 5 425/432 51 1111. c1 ..B28b 3/12,B28b 5/02 Primary Examiner-J. Spencer Overholser Assistant Examiner-David S. Safran Attorney, Agent, or Firm-Holman & Stern ABSTRACT A mill is disclosed which is provided with a device for feeding plaster concrete wastes back to a concrete mixer, said device comprising means for receiving and crushing the wastes, as well as means for conveying said wastes back to the concrete mixer.

1 Claim, 5 Drawing Figures PATENTEDHAYZI I974 SHEET 2 [IF 5 PATENTEDMYPI 197 SHEEI S 0? 5 lli/4 F/GJ . 1 MILL FOR MANUFACTURE OF PLASTER CONCRETE ARTICLES BACKGROUND O THE INVENTION This invention relates generally to equipment used for manufacturing plaster Concrete articles by way of continuousrolling thereof and more particularly, it relates to mills for the manufacture of plaster concrete articles. Y

The method of manufacturing plaster concrete articles by way of continuous rolling thereof is the most advanced one in that with little labour consumption, it is possible to obtain articles of uniform physical and mechanical properties with accurate dimensions, having high quality in the surfaces.

Articles made of plaster concrete are used for making various partition walls in dwelling houses, public buildings, and lavatory and bath cabins. Such articles may also be used as lining materials for the inner surfaces of main walls, as well as for floor slabs being laid under parquet or plastics.

Prior art mills for manufacture of plaster concrete articles by way of continuous rolling thereof comprise a conveyor with upper and lower moulding strands and mount a concrete .mixer, a gauging drum with a' set of gauging rolls and a vibrating unit. I I

In conventional mills articles, e.g. plaster concrete articles, are'manufactured by means of a continuous supply of a plaster concrete mixture prepared in a concrete mixer 'ontoj'the surface of the moulding (lower) strand of the mill, theframeworks of panels to be manufactured beingplaced on the strand beforehand, as it advances, to serve as moulds.

The vibrating unit operates in an intermittent manner to ensure better distribution and compaction of plaster concrete mixture.

.The frameworks being filled uniformly with plaster concrete mixture along the whole width thereof, are moved under the gauging drum to the set of the gauging rolls which define the final thickness of moulded articles and cover them with the upper moulding strand.

Experiences in operating the above-described mills have shown that during the manufacture of plaster con crete articles, material wastes will inevitably appear, said material wastes being formed mainly from filling with the door ways, window openings, etc., of the panels being manufactured.

In accordance with the available statistical data, the

amount of such material wastes constitutes, on the average, 6-8 percent of the total volume of the plaster concrete required to manufacture the articles.

Until recently plaster concrete wastes formed in the course of operation of millsof the above-described type have not been utilized. However, research and experiments have shown that plaster concrete wastes can be used as an active filler 'in the manufacture of plaster concrete articles.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a mill for the manufacture of plaster concrete articles, that will make it possible to save inactive raw materials by utilization of plaster concrete mixture wastes.

The objectives of this invention areaccomplished by a mill for the manufacture of plaster concrete articles by way of continuous rolling between the upper and lower endless moulding strands of plaster concrete mixture which is fed into a mould from a concrete mixer. According to the present invention, a device is provided which is adapted for feeding plaster concrete wastes back to the concrete mixer, said device comprising a unit which is located at the point of separation of a moulded article from the lower moulding strand which receives said wastes, means for receiving and a crushing wastes, and means associated with said unit to convey said wastes back to the concrete mixer.

The subject-matter of the present invention consists in the following:

Due to the provision of the mill with the device for feeding'plaster concrete wastes back to the concrete mixer, plaster concrete wastes are removed from the moulded article as excess material which remains on the filled-up framework at the moment of separation of the moulded article from the lower moulding strand during the movement thereof. The wastes thus removed are fed to the receiving means and, then, to the crushing means.

After being crushed, the wastes are conveyed to the concrete mixer to be mixed with plaster concrete mixture, thereby partially substituting the inactive filler thereof.

The present invention provides for almost complete utilization of wastes during the manufacture of plaster concrete articles and, consequently, the consumption of the .inactive fillers used for the preparation of the plaster concrete mixture is lowered by 5-6 percent.

BRIEF DESCRIPTION OF THE DRAWINGS The following description of an exemplary embodiment of the mill for the manufacture of plaster concrete panels is given with reference to the accompanying drawings, in which:

FIG. 1 is a side elevation'al view of the mill according to the present invention;

FIG. 1 is a side elevation view of the mill according to the present invention;

FIG. 2 is a top view of the mill;

FIG. 2' is top plan view of the mill according to the present invention; and

, FIG. 3 is a sectional taken along line Ill-III in FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the accompanying drawings, a mill for the manufacture of plaster concrete panels comprises a conveyor which is essentially two endless moulding, upper l and lower 2, strands (FIGS. 1 and 2); a gauging drum 3 with a set of gauging rolls 4 disposed above the upper moulding strand 1; a vibrating device 5 disposed under the lower moulding strand 2, a single-shaft continuous-operation concrete mixer 6 located above the conveyor; a charging-and-batching device comprising four hoppers 7 provided with volumetric batching units 8 located thereabove; a device for feeding plaster concrete wastes back to the concrete mixer 6 which is essentially a means for receiving wastes from the strand made as a hopper 9 and located at the point of separation of a moulded articles from the lower moulding strand 2, a means for crushing wastes made as an auger being connected to said receiving means. The blades 11 are mounted on the end surface of the body of the auger 10.

Said conveying means are essentially a horizontal conveyor 12 disposed under the auger body and an inclined conveyor 13. At one side, said conveyor 13 adjoins said horizontal conveyor 12 and at the other side, it adjoins an auger 14 disposed above the concrete mixer 6. One end of the conveyor formed by the two endless moulding strands l and 2 is connected to a power driven receiving roll table 15, the other end thereof being adjacent to an over-running roll table 16 which is terminated in a tilter 17.

The unit for receiving and crushing wastes may comprise other devices which accomplish the sametasks and may be fashioned, for instance, as a horizontal jaw crusher having a body which is adapted to receive wastes to be crushed. Alternatively, a system of augers may be used as the means for conveying crushed wastes to the concrete mixer, said augers being arranged in such a manner as to ensure continuous delivery of wastes to the concrete mixer.

The mill for the manufacture of plaster concrete panels shown in the accompanying drawings functions as follows.

Wooden frameworks of external wall panels with window openings are continuously placed one after another on the receiving roll table (FIGS. 1 and 2), and are conveyed in the direction indicated by arrow A" onto the lower moulding strand 2 in the zone of delivery of plaster concrete mixture.

Dry components (plaster, saw-dust and sand) of the mixture are supplied from the hoppers 7 through the volumetric batching units 8 to the single-shaft continuous-operation concrete mixer 6, which is also supplied with water necessary for preparing the plaster concrete mixture.

The plaster concrete mixture thus prepared is poured as a continuous flow onto the lower moulding strand 2 through a discharge opening (not shown) and fills the wooden frameworks disposed on said strand.

Due to the reciprocating movement of the concrete mixer 6 located above the moulding strand 2 and the periodical actuation of the vibrating unit 5, the plaster concrete mixture is uniformly distributed along the width of the strand 2.

The wooden frameworks being filled with the plaster concrete mixture are conveyed to under the upper moulding strand 1 and are covered thereby.

Then, the gauging drum 3 and the set of gauging rolls 4 perform compaction and gauging of panels until the required thickness is obtained.

While being between the upper and lower strands 1 and 2, the moulded plaster concrete panels get set and become ready for striking at the point of separation from the lower moulding strand 2.

The excess material, being formed in window openings and in front of the leading panel during the starting of the mill, i.e., plaster concrete wastes, are removed at the point of separation of panels from the lower strand 2 and are fed into the hopper 9 of the device for feeding back the wastes. The panels are further conveyed to the over-running roll table 16 which is driven by two drives, by the drive of the lower moulding strand 2 and by its own drive that imparts to it a speed which is ten times higher than the speed of the lower moulding strand 2. This increase in the speed provides for a time reserve that is necessary for subsequent technological operations (tilting, finishing of the panel face, etc.).

The panel is transferred to the tilting device 17 at an increased-speed, said panel being brought from the horizontal position to the vertical one, and transported further for drying.

The plaster concrete mixture wastes, being obtained in the hopper 9, are conveyed by the auger 10 (FIG. 3) to its face surface in the direction of the blades 11 which perform the crushing of the wastes.

The crushed wastes are supplied onto the horizontal conveyor 12 through a discharge port 18 (FIG. I) and, then they are transported by the inclined conveyor 13 to the auger 14 which feeds them into the concrete mixer 6.

In the concrete mixer, the crushed wastes are mixed with newly supplied dry' components to serve as an inactive filler of the plaster concrete mixture.

As it has been shown above, the mill, according to the invention, ensures a rather complete utilization of plaster concrete wastes during the manufacture of moulded panels, thereby providing for savings in the inactive raw materials.

We claim:

1. In a mill for manufacturing plaster concrete articles, comprising upper and lower moulding strands, plaster concrete articles being formed therebetween in moulds through continuous rolling, a single-shaft concrete mixer means for supplying the plaster concrete mixture into a mould, means for returning plaster concrete wastes located at the point of separation of a moulded article from said lower moulding strand, and said returning means including means for subsequently conveying said wastes back to said concrete mixer means, the improvement comprises said returning means further including means for crushing said wastes, said crushing means being in the form of an auger with blades disposed thereon for crushing said wastes, said auger moving said wastes to said means for conveying it back to the concrete mixer means.