US2569952A - Cement gun apparatus - Google Patents

Description

Ot. 2, 1951 1. M. RIDLEY CEMENT GUN APPARATUS Filed July 27, 1948 INVENTOR: IAN M. P/DLEY BY a A TTOR/VEKS.

Patented Oct. 2, 1951 UNITED STATES PATENT OFFICE 2,569,952 CEMENT GUNAPPARATUS Ian M. Ridley, Burbank, Calif.

Application J uly. 27, 1948, Serial No. 40,922

4 Claims. "(CL 91 44) This invention relates to cement gun sandblasting equipment and the like, and more particularly to a new and improved sandblasting or cement gun apparatus of improved overall and metering construction.

Prior art devices must ordinarily be shut down while they are recharged with raw materials, such as cement or sand or both. Their operationis consequently intermittent. Presently known apparatus also tends to deliver sand or mixtures of sand and cement with an uneven, irregular and often spasmodic flow so that the size of the apparatus is ordinarily excessive for the purposes for which the instant apparatus is intended, and the supply of material to the delivery nozzle and place of application is relatively excessive because of the absence of a satisfactory metering device.

v Prior art apparatus is also subject to excessive wear in use and the working parts are replaceable only with difficulty.

. Therefore an object of this invention is. to avoid the above obiections and to provide an apparatus usable either as an, applicator for a mixture of cement and sand or as a sandblasting unit which need not be shut down while in use, which may be readily made from available ma terials, which affords easy access to all of its working parts for replacement or repair, and which provides a steady controllable and continuous supply of preferably dry mixed cement and sand as desired.

It is another object of this invention to provide a tank type cement gun apparatus which is usable as a sandblaster, all parts of which may be powered by a single compressed air source and having anoverall simplicity of construction.

It is another object of this invention toelimie nate customary gears and other complicated mechanism for performing the desired function.

Another more specific object of. the invention is the provision of an improved metering means associated with a new and improved metering orifice whether considered either alone or .in the cited combination.

Another further object of the invention is the provision of a metering apparatus bearing a unique and satisfactory relationship to the feed chamber with Which it is' associated.

It is moreover an object of this invention to provide improvements over prior art devices generally intended to be put to a similar use.

With these and other objects in view, the invention consists in the construction, arrangement and combination of the various parts of the device whereby the objects contemplated are attained, as hereinafter set forth, pointed out in the appended claims and illustratedjin the accompanying drawings.

2 In the drawings: Figure 1 is a vertical sectional view, parts being cut away of an apparatus illustrative of this i I invention.

Figure 2 is a vertical sectional view as on a line '2-2 of Figure 1.

Figure 3 is a detailed enlarged View of the metering mechanism.

Figure 4 is a detailed view of a modified form of metering orifice.

Referring more particularly to the drawings, an'apparatus embodying this invention by way of illustration and not of limitation comprises a tank l divided into an upper compartment 5 i and a lower compartment 12. These compartments may be respectively fitted as with hemispherical cups [3 and 14, respectively, comprising check valves, the upper one l3 ofwhich, at least,

I may be raised or lowered by means of a Windlass type construction such as a handle l5 or automatically by compressed air as will be seen. The turning of the handle 15 may lower the hemispheres from the positions illustrated in Figure 1 by straightening the toggle links l1, l8, of the valve 13, or if desired, of the valve l4 as Well. The lower link l8 may be provided with a ball set in a suitable socket IQ for universal movement.

The upper compartment H is defined by a top transverse wall 2|, optionally funnel-shaped in the 'manner of a hopper, and a preferably funnel-shaped lower wall 22 which incidentally also comprises the top of the chamber l2. Orifices 24 and 25 associated with the hemispheres l3 and 14 are provided with packing rings 26 or the like to insure an air-tight closure of the hemispheres thereagainst.

A tube 23 and rod 29 project downwardly, most desirably, at an angle through the walls 2| and 22 so as to clear the openings 24 and 25, to provide outside mounting for the driving means as will be seen, and to facilitate acquisition of a desired angle for the metering means as will also be set forth hereinafter. The rod 29 extending therethrough is accommodated by ported caps to at the ends of the tube 28, and the tube is made air-tight in its passage through the tank as by suitable ring packing 21.

An air motor or the like 32 is operatively connected to the rod 29 to cause the rotation thereof, whereby the agitator arms or stirrers 33 welded to the rod 29 are caused to rotate and mix dry cement and sand 35 disposed in suit able proportions within the tank H3. The tube 28 may have either packing or bearings 36 for ribbon 3! extending into a preferably threaded I nipple 38, a sleeve 39, and another nipple 48 formed with a tapered shoulder 4I providing a constricted tubular-shaped orifice 42.

.A notch 43 formed in the lower end of the ribbon 3'! thereby forms wings 48 which, upon rotation of the rod 29 and the ribbon 31, optionally secured thereto in a releasable manner as by a keyed or recessed hub 49 and set screw arrangement, assist the screwing action of the ribbon 37 in metering a dry sand or cement and sand mixture 35 through the orifice 42.

A stirrer 33 may be welded or reverse threaded as by means of a sleeve or the like (not shown) to the hub 49.

The nipple 48 may be formed integrally with the shoulder portion 4| or separately therefrom as a removable insert as within the sleeve 39. Said nipple 40 is threaded into a T 5| across the run of which a pipe 52 leading from an air supply (not shown) is passed. A boss 53 may bethreaded into a suitable reinforcing shoulder 56 at the bottom of the tank III in order to support the last mentioned mechanism in a preferred angular position as shown.

An outlet control valve 60 is openly connected with the upper chamber II and an inlet control valve SI interconnected with the air supply pipe 52, preferably after the passage of the latter through a pressure reduction valve 62, controls the flow of air from the supply pipe 52 to the upper, chamber II. V

The apparatus above described may be placed on wheels, skids, or the like for mobility, or may be provided with a supporting framework such as legs 65 to support the same in a verwhich may be lowered from its closed raised position by rotation of the handle I5, optionally also, or in addition, opening the outlet valve 60 any air under pressure within the upper chamber II will be exhausted to the atmosphere, the inlet valve BI meanwhile having been closed in either case.

When the upper chamber II has been filled with entrant raw materials to a sufficient extent the valve 60 is closed and the valve 6 I then opened permitting air under pressure to enter the chamber II and forcing the hemisphere I3 closed. Compressed air from its source in passing through the pressure regulator valve 52 bypasses the inlet valve BI and enters the lower chamber I2 by pipe 63, whereby a constant pressure is maintained within said lower chamber normally equal to that within the upper chamber I I when the inlet valve GI is open. Thereby, the weight of an entrant dry sand and cement mixture above and upon the hemisphere I4 causes a pressure differential which ticalposition as shown. In any event an air supply hose separate from the supply pipe 52 may be directly connected to the compressor or other air source (not shown) for operating the motor 32 which may likewise be provided with a regulating mechanism. of conventional construction to control the speed thereof. connection 66 may be continuous with the run of the T 5| and lead to a delivery nozzle 61 also of conventional construction. An auxiliary air supply hose 68 or the nozzle 51 may connect with the compressor source or the delivery hose 65, and another hose 69 may be connected to a water source to convey air and water, respectively, under pressure to the delivery nozzle 67 in order to disperse and throw the dry sand mixture from the T 5|, optionally a venturi, and to spray the same with water vapor, to moisten the same to a desired extent so that it may adhere to a surface upon which it is directed. The apparatus is used for sandblasting. Manifestly the pressure reduction valve 62 may be eliminated or opened to its fullest extent, and the air and auxiliary water hoses 68 and 69 leading to the nozzle may be turned off or removed.

Y The handle I5 for controlling the upper hemisphere I3 for example may have a horizontal rod 82 extending therethrough provided with a sleeve bushing 83 with a cap 84 and rubber gasket 85 therein to make the same air-tight and also provided with a cup bushing 86 at its opposite end.v The links otherwise connected to the rod 82.

Operation I! preferably are welded or A hose automatically opens said valve I4 and permits the dry mixture to fall into the chamber I2 as the latter is exhausted, i. e., it may be noted that due to its weight the hemisphere I4 may remain open even when pressures within the chambers I I and I2 are equal as when the outlet valve 60 is closed and the inlet valve BI is opened.

However, upon the opening of the valve 60 and closing of the valve BI the air pressure within the lower chamber I2 exceeds that within the upper chamber I I forcing a closing movement of the hemisphere I4. Valves I0 and 'II in the supply pipe 52 control the flow of air to the lower chamber I2 and the nozzle 61.

During the normal operation of the apparatus, the passage of air from the source, through the pipes 52, through the T '5I, and thence into the nozzle 61, carries with it the sand and cement mixture as it is metered through the orifice 42. In the nozzle 61, the preferably, though not necessarily, dry mixture 35 prior to its ejection from the tank 66 is wetted, as stated, with a spray of desired density formed by the injection of water or air and water under pressures of approximately 60 and 80 pounds respectively, thereby 48 preferably conform to the corresponding surface of the shoulder H and may be either slidable thereon or only placed in proximity thereto.

The notching 43 of the lower end of the screwlike ribbon 31 provides an appropriate outlet for the bulk of material contained within the enlarged sleeve portion 39. In combination with said slot and said interior of the sleeve 39 the fingers 48 in their revolving movement do not jam but provide a free stirring movement for the granular or powdered material thereabove. An evenness of flow is thereby obtained of said material which drops through the orifice 42 and into the TM where the same is picked up by the air stream passing through the supply pipe 52 to the left as illustrated in the drawings. In view of the granular nature of the material used the pressure of the air within the lower chamber I2 passes in part through the material because of said porous nature and assists in the transmittal of the same through the nipple 38 and'the sleeve 39.

comprising the nipple 38 and sleeve 39 further Moreover the amount of extension of the twisted ribbon 31 into the upper orifice portion regulates and controls the flow through the restricted portion of the orifice 42.

As illustrated in Figure 3 said orifice 42 is shown to have substantial vertical depth from the bottom of its top tapered edge to the top of its lower tapered edge, but the same may be reduced to a relatively thin line I3 as illustrated most clearly in Figure 4, wherein other corresponding parts are designated by like numerals to those illustrated in Figures 1, 2 and 3. The orifice 13 per se is therefore shown as being without substantial cylindrical wall portions similar to those 42 of Figure 3.

Rotation of the screw 3'! against the shoulder 4| may be achieved in either embodiment in order to retain a proper working condition of these parts to maintain a sharp line of contact therebetween and to prevent sticking by entrance of powdered or granular material between the adjacent sliding surfaces.

The construction of this apparatus is such that may be readily dismantled and any or all of the parts removed for replacement or repair. The notch 43 may thereby be enlarged or reshaped as needed and the length of the screw 31 may be regulated by suitable telescopic adjustment in the keyed relationship of the hub 49 and the shaft 29 to provide relative axial movement or provision for adjustment.

This invention features the provision of a convenient uniformly operating sandblasting and/or cement spraying apparatus of outstanding performance. A satisfactory size has been found to be an approximate 40" height for the tank and an'approximate 18" diameter therefor, the openings 24 and 25 being preferably approximately 4" in diameter, and the angle of slant of the transverse portion 22 and bottom 80 approximately 45. The agitator 33 may be shaped to conform to such bottom portion 80 along the most proximate wall thereto. The rod 29 and screw 37 may, if desired, although this is not the preferred construction, be given a vertical position to the other parts. A slight clearance between the lower end of the twisted ribbon 31 and shoulder 4| has also been found desirable with certain types of granular and powdered material.

While I have herein shown and described my invention in what I have conceived to be the most practical and preferred embodiment, it is recog-- nized that departures may be made therefrom within the scope of my invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices.

The invention having been herein described, what I claim as new and desire to secure by Letters Patent is:

1. In a cement gun apparatus comprising a hopper for dry sand and/or cement, a substantially vertical outlet formed at the bottom of the hopper, metering means rotatable on a substantially vertical axis in alignment with andabove said outlet, drive means for rotating said metering means. a source of compressed air, a delivery means for discharging said dry material from a station below said outlet to a point of use by means of said air, said metering means comprising a vertical screw-shaped ribbon, said outlet being formed with a seat thereabove, said ribbon having a bifurcate lower end portion straddling said outlet, the lower ends of the biiurcate portion being slidable rotatively upon said seat, and means for rotating said ribbon.

2. In a cement gun apparatus comprising a hopper for dry sand and/or cement, a substantially vertical outlet formed at the bottom of the hopper, metering means rotatable on a substantially vertical axis in alignment with and above said outlet, drive means for rotatin said metering means, a source of compressed air, a delivery means for discharging said dry material from a station below said outlet to a point of use by means of said air, said metering means comprising a vertical screw-twisted ribbon, said outlet being formed with a seat thereabove, said ribbon having a bifurcate lower end portion straddling said outlet, the lower ends of the bifurcate portion being slidable rotatively upon said seat, and means for rotating said ribbon.

3. In a cement gun apparatus comprising a hopper for dry sand and/or cement, a substantially vertical outlet formed at the bottom of the hopper, metering means rotatable on a substantially vertical axis in alignment with and above said outlet, drive means for rotating said metering means, a source of compressed air, a delivery means for discharging said dry material from a station below said outlet to a point of use by means of said air, said metering means comprising a vertical screw-shaped ribbon, said outlet being formed with an annular restricted shoulder having a tapered seat, said ribbon having a bifurcate lower end portion straddling said outlet, the ends of the bifurcate portion being tapered to correspond with the taper of the seat and to make line contact therewith on each side thereof and being rotatably slidable thereon, and means for rotating said ribbon.

4. In a cement gun apparatus comprising a hopper for dry sand and/or cement, a substantially vertical outlet formed at the bottom of the hopper, meterin means rotatable on a substantially vertical axis in alignment with and above said outlet, drive means for rotating said metering means, a source of compressed air, a delivery means for discharging said dry material from a station below said outlet to a point of use by means of said air, said metering means comprising a vertical driving member, said outlet being formed with a seat thereabove, defining a central opening, said vertical driving member having opposed horizontally spaced finger-like stirring elements depending therefrom and straddling said outlet, the lower ends of said fingerlike elements each moving around said seat, said finger-like stirring elements defining a space between them and above the opening in said seat, and means for rotating said driving member.

IAN M. RIDLEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 699,405 Newhouse May 6, 1902 998,762 Faller July 25, 1911 1,047,680 Mills et al Dec. 17, 1912 1,333,079 Kaufmann Mar. 9, 1920 1,559,666 Bernier Nov. 3, 1925 1,718,507 Wenzel et al June 25, 1929 1,737,044 Conley Nov. 26, 1929 1,954,005 Westberg et a1 Apr. 10, 1934 2,006,757 Bostrom July 2, 1935

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