US 2524919 A
Description (OCR text may contain errors)
Oct. 10, 1950 E c 2,524,919
POWDER DISPENSER Filed May "9, 1945 2 Sheets-Sheet 1 65 7 & INVENTOR EDWARD MEINCKE BY Z ATTORNEY Oct. 10, 1950 E, K 2,524,919
POWDER DISPENSER Filed May 9, 1945 2 Sheets-Sheet 2 INVENTOR DWARD MEINCKE VBYE gig e;/.
ATTORNEY Watented Oct. li@, i5
2,524,919 POWDER DISPENSER Edward Meincke, Summit, N. J., assignor to The Linde Air Products Company, a corporation of Ohio Application May 9, 1945, Serial No. 592,906
This invention relates to powder dispensers, and more particularly to powder dispensers wherein powdered material is entrained by a flowing stream of a gas, such as air or acetylene, and conducted to a point of use. The invention involves improvements over the powder dispensers disclosed in Patent 2,327,337 issued August 24, 1934 to Charles J. Burch.
Among the objects of the present invention are the provision of a novel powder dispenser wherein large quantities of powder' may be picked up continuously by a flowing stream of gas; and whereby the quantity of powder carried by the gas may be accurately controlled from the outside of the powder dispenser. Other objects are the provisio of a powder dispenser in which powder is prevented from settling into the discharge conduit when the dispenser is idle; in which a removable and replaceable dispensing unit is provided; and in which there is a false bottom in the powder container and provision is made for equalizing the gas pressures above and below the false bottom.
Other objects are to provide a. powder dispens er wherein the access of powder to the space between relatively movable parts is prevented; to provide a powder dispenser whereby powder can be dispensed from a single powder container to a plurality of conduits; and toprovide a powder dispenser which is simple, compact, and emcient.
The above and other objects, and the novel features of the invention, will become apparent from the following description having reference to the accompanying drawings, wherein:
Fig. 1 is a vertical sectional view of one form of powder dispenser embodying the invention;
Fig. 2 is a side elevational view, partly broken away and in section, of another and preferred form of powder dispenser embodying the invention;
Fig. 3 is an enlarged vertical sectional view of a part of the powder dispenser of Fig. 2; and
Fig. 4 is a side elevational view showing a part of still another form of powder dispenser.
Referring to Fig. 1, one form of the powder dispenser of the invention comprises a closed vertical cylindrical container C, and a removable and replaceable dispensing unit D detachably secured to the bottom of the container. The container C has a top wall I I provided with an opening l5 for the introduction of powder, closed by a plug I'I bearing against a gasket l9; and a bottom wall 13 provided with 'a central opening 2| through which part of the dispensing unit D extends into the container.
2 To facilitate the flow of powder to the bottom of the container C, a partition or false bottom 23, having generally the shape of an inverted cone with steeply sloping sides, is brazed or otherwise secured within the container C with its lower end flush with the rim of the opening 2i, and with its upper end engaging the side walls of the container. The annular chamber 25 formed below the false bottom 23 thus is sealed from the chamber 21 above the false bottom. To prevent buckling of the relatively thin partition 23 by the weight of powder and the pressure of gas, a conduit 29 at one side of the container C passes through the partition and establishes communication between the two chambers 25 and 21 for equalizing the gas pressures. The upper portion of the conduit 29 is bent so that its end faces downwardly to prevent the entrance of powder therein while the container C is being filled. The container C may be supported in any suitable way; as by a plurality of legs 3!, two of which are partially shown in the drawing.
The dispensing unit D includes a disc shaped body 32 bolted tightly to the bottom wall I3 and compressing a gasket 33 against the wall to provide a gas-tight seal. A vertically arranged hollow powder barrier such as a dome 35, having an open lower end threaded into a central passage 34 in the body 32, projects from the inside of the body upwardly into the chamber 21. Upwardly and inwardly inclined powder inlet ports 31 extend through the wall of the barrier 35 for establishing communication between the interior of the dome and the portion of the container C outside of the dome. A powder discharge conduit 39, which has an open upp r end or entrance within the barrier .35 above the level of the ports 31, is brazed or otherwise secured gas tightly in an adaptor 4| threaded into the lower end of the passage 34 and extends downwardly through the adaptor to the outside of the powder dispenser, where it may be coupled to a hose or other conduit 65 for carrying away the powder.
A gas injector or bleeder tube 41, shaped like an inverted U, has one leg extending downwardly through an opening in the top of the barrier 35 a substantial distance into the discharge tube 39 through its entrance in spaced relation to the conduit or passage extending through the body 32 from the outside to the inside of the container C and into the barrier 35 and the discharge conduit 39.
Gas is supplied to the bleeder tube 41 by a branch conduit 53, including an elbow 54 threaded into the passage controlled by a needletype throttle valve 55 for regulating the flow of gas. The conduit 53 is connected to a main gas supply conduit 51 by a pipe T 59, which is also coupled to a second branch conduit 6| connected at its upper end into the container C near the top thereof and above the level of powder. The flow of gas through the main conduit 51 to the branch conduits 53 and 6| also is controlled by a needle-type throttle valve 63.
In the operation of the powder dispenser shown in Fig. 1, the container C is filled through the opening I5 with powder, such as powdered iron, to a level just below the upper ends of conduits 6| and 29. After plugging the opening I5, the valve 63 is opened, and the valve 55 is adjusted to give through the ports 31 to the interior of the barrier dome 35, is carried upwardly to the entrance of the discharge conduit 39 both by the gas which works its way down through the mass of powder and by the suction created by the gas flowing from the bleeder conduit 41 into the dome and der. It has been found possible to carry powder through long lengths of hose 65 at rates between 1b./min. and 3 lb. /min. with gas flows in the range of 5 to cu. ft./hr. For example, fine iron powder has been carried through the conduit by compressed air at the rate of about 1 'lb./min. with a pressure of 5 lb./sq. in. in the container C and an air flow of 15 cu. ft./hr. The powder flows and the gas pressures may vary, depending upon the type of powder, its screen analysis, its specific gravity, and the contour of the conduit system.
By terminating the discharge conduit 39 above the level of the ports 31, powder is prevented from settling into and clogging the discharge conduit when the dispenser is idle. Thus, the dispenser is always ready to go into operation instantly.
When the dispensing unit D is to be removed from the powder dispenser for repair, replacement, or cleaning of parts, it is only necessary to uncouple the pipe union 56 from the rest of the conduit 53, and the conduit 65 from the discharge conduit 39, after which the bolts holding the body 32 to the bottom wall I3 may be removed. If the conduits 53 and 65 are flexible hoses, it is not even necessary to uncouple these conduits before removing the bolts.
In the preferred embodiment of the invention, shown in Figs. 2 and 3, a powder container C has a frusto-conical bottom wall 1| terminating at its lower end in a short skirt 13 which is welded to a heavy annular flange 15 surrounding an opening 11. The top of the container C is closed gas tightly by a heavy cover 19 carrying an annular gasket 8| which rests on the upper edge of the container. Several bolts 83 are swiveled to brackets 85 on the container C for movement into and out of slots 81 in the cover 19. When the bolts 83 are within the slots 81, the cover is held tightly in place by heavy wing nuts 89 threaded on the bolts and bearing against the top surface of the cover.
The dispensing unit D includes a heavy detachable body 9| bolted tightly to the flange 15 and sealed against gas leakage by a gasket 93 interposed between the body and the flange. A unitary adjustable powder discharge conduit 95, having a conical counterbore 96 in its upper or entrance end, is threaded into a central bore 91 in the body 9| and projects upwardly through a central counterbore 99 into the container C, the construction being such that the discharge conduit can be moved upwardly or downwardly by rotating it. A handle IOI is secured to the bottom of the discharge conduit for adjusting its position, and a pointer I03 associated with the handle travels over a scale I05 on the body 9| for indicating the position of the discharge conduit. When the desired adjustment has been obtained, the position of the discharge conduit 95 is fixed by tightening a lock-nut I04 against a gasket I06 interposed between the lock-nut and the body 9 I.
A barrier dome I01, having side ports I09 below-thetop of the discharge conduit 95 for the entrance of powder from the container, is arranged over the discharge conduit in spaced relation thereto and is threaded at its lower end into the counterbore 99. For preventing the access of powder to the space between the threads of the discharge conduit 95 and the bore 91, an annular gaskfet III of rubber or like resilient material is wedged between the walls of the discharge conduit and the counterbore 99 and is clamped in position between the bottom edge of the dome I01 and the bottom of the counterbore. With this construction, the position of the conduit 95 can be adjusted easily at all times because exclusion of powder from the threads prevents galling and binding.
Gas is supplied to the dispensing unit D by a supply conduit I I3 coupled to one side of the body 9| and opening into a lateral passage 5 which in turn connects with a vertical passage I I1. Gas flow through conduit 3 is regulated from outside the container C by a valve I I4. A vertical nipple 9 extending up into the container C outside of the dome I01 is threaded at its lower end into the passage Ill and at its upper end is detachably coupled to one leg of an inverted U shaped tube I2 I. The other leg of the tube I 2| is coupled to a stationary inpector I23 which is threaded into the top of the dome I01 and projects downwardly therein in axial alignment with the discharge conduit 95. The injector I23 has a relatively large diameter portion I24 above the entrance of the discharge conduit 95, an abrupt squar shoulder I25, and small diameter nipple I21 which extends downwardly from the shoulder within the discharge conduit in spaced relation to the wall thereof. With this construction, relative adjusting movement between the injector I23 and the discharge conduit 95 toward and away from one another varies the size of the clearance space between the shoulder I25 and the wall of the conical counterbore It, thus varying the quantity of powder which can enter the discharge conduit. I
For supplying gas to the space in the container above the level of the powder, the gas supply conduit H3 extends from below the container up through the bottom wall II to a position near the top of the container, where it is so curved that its open upper end faces downwardly, thus ex-- cluding powder from the conduit when the container is being filled.
Communication between the conduit H3 and a source of gas for operating the dispenser is established by a second conduit I29 extending through a side wall of the container C and coupled to the conduit H3 within the container. For regulating the gas pressure in the dispenser an automatic pressure regulator I30 of well known construction is interposed in the conduit I29, and a gas cleaner I3I of a standard type is also installed in the conduit I29 upstream of the regulator, both the cleanerand the regulator being supported by a bracket I32 welded to the outside of the container C.
- The operation of the powder dispenser of Figs. 2
and 3 is identical with that of the dispenser of Fig. -1. However, the dispenser of Figs. 2 and 3 is'especially advantageous because the rate of powder dispensing can be controlled very accurately by rotating the discharge conduit 95 from adjust the dispenser to give a maximum rate of powder dispensing with any given rate of gas flow, or, if desired, any desired ratio of powder to gas in the powder-laden gas stream can be obtained. Another advantage lies in the more compact and simple construction wherein a double bottom is eliminated and the gas conduits are partially enclosed within the container itself. Furthermore, the formation of the clearance space between a conical surface 96 and an abrupt shoulder I25, and the-location of the inlet ports it! below the top of the discharge conduit 95 permit effective dispensing of powders of nonuniform size, such as a mixture of relatively course particles with relatively fine particles.
In the modification of the invention shown in Fig. 4, a detachable dispensing unit D" is secured to the bottom of a container C" in the manner described in connection with Figs. 2 and 3. A plurality of identical powder dispensing devices I33 of the type described in detail in connection with Figs. 2 and 3 are arranged eccentrically in the dispensing unit D" and are adapted to be coupled to a plurality of powder conveying conduits by nipples I34 and I35. Gas is supplied to the several dispensing devices by separate tubes I36 and I31 connected to a single gas supply conduit H3, and controlled by separate valves I39 and III, respectively. Using such a construction two or more powder conveying conduits can be supplied with powder simultaneously from a single container by an appropriate number of powder dispensing devices. Individual regulation of gas and powder flows can be obtained by adjusting the individual gas control valves, and by adjusting the positions of the individual powder discharge conduits 95 in the manner described in connection with Figs. 2 and 3.
' Specific embodiments of the invention have 6 been described in detail only to illustrate the principles of the invention. It is to be understood that changes in the construction and relative arrangement of parts can be made within the scope of the invention, as defined by the appended claims.
1. A powder dispenser comprising a container adapted to hold a supply of powder; a hollow powder barrier within said container having a lower end engaging the bottom thereof, said barrier having a side wall provided with port means therethrough establishing communication between the interior of said barrier and the portion of said container outside of said barrier for admitting powder to said barrier; a powder discharge conduit separate from said barrier having an entrance in said barrier spaced from said side wall, said conduit extending downwardly from said entrance to the outside of the dispenser; and a gas injector extending downwardly into said powder discharge conduit through said entrance in spaced relation to the internal wall thereof.
2. In a powder dispenser, a closed container having top, side, and bottom; a. false bottom adapted to support a body of powder closely fitting said side and bottom, said false bottom partitioning said container into upper and lower chambers; means for introducing gas under pressure into said upper chamber; and a pressure equalizing conduit extending from said lower chamber to a position near the top of said upper chamber so located as to be above the level of powder therein.
3. A powder dispenser comprising a closed container having a top, side, and bottom; a hollow dome within said container adjacent to said bottom, said dome having a side wall provided with port means establishing communication between the interior of said dome and the portion of said container outside of said dome for admitting powder to said dome; a false bottom in said container closely fitting said side and bottom for supporting a body of powder, said false bottom sloping inwardly and downwardly toward said dome for guidingpowder thereto, and said false bottom partitioning said container into upper and lower chambers; a powder discharge conduit having an open upper end in said dome spaced from said side wall, said conduit extending downwardly from said open end to the outside of said dispenser; a gas injector extending downwardly into said powder discharge conduit through the open end thereof; means for introducing gas into said container near the top thereof above the level of such powder; and a pressure equalizing conduit extending from said lower chamber to a position near the top of said upper chamber so located as to be above the level of such powder.
4. In a powder dispenser, a powder container having a bottom wall; a hollow dome within said container having a lower end engaging said bottom wall, saidjdome having a top and a side wall provided with port means establishing communication between the inside of said dome and the part of said container outside of said dome for admitting powder to said dome; a powder discharge conduit extending from the inside of said dome down through the bottom of said container to the outside thereof, said discharge conduit including a portion projecting up into said dome and terminating at its upper end in an upwardly flaring entrance; a gas injector conduit extending centrally through said top and projecting down into said dome and into said discharge con- 7, duit; and a shoulder encircling said injector conduit above the lower end thereof and arranged close to but spaced from said upper end of said discharge conduit.
5. In a powder dispenser in accordance with claim 4, said powder discharge conduit comprising a tube adjustable from outside said container in directions toward and away from said shoulder.
6. A powder 'dispenser comprising a powder container having a bottom wall; a hollow dome within said container having a. lower end enga ing said bottom wall, said dome having a top and a side wall provided with port means therethrough for admitting powder into said dome from the part of said container outside of said dome; a gas injector projecting downwardly through said top into said dome; a powder discharge tube having an inlet in said dome aligned with said gas injector, said tube extending downwardly through said bottom wall in threaded engagement therewith to the outside of said container, said tube being adjustable longitudinally by rotational movement thereof from outside said container to vary the position of said inlet with respect to said gas injector and said ports for regulating the rate of powder dispensing; and an indicator for indicating the adjustment of said inlet with respect to said injector tube and said ports, said indicator comprising a radial pointer member and an arcuate scale member cooperating therewith, one of said members being carried by said discharge tube and being rotatable therewith, the other of said members being stationary on the outside of said dispenser.
- 7. A powder dispenser comprising a powder container having a bottom wall; said bottom wall having a bore extending upwardly from the outside thereof, a threaded counterbore extending downwardly from the inside thereof; an upwardly facing shoulder between said bore and counterbore; an annular gasket of resilient material on said shoulder 'having at least a portion thereof within the outline of said bore; a hollow dome within said container threaded into said counterbore and having a lower end bearing against said gasket to hold said gasket in position, said dome having a side wall provided with port means therethrough for the admission of powder thereto; and a longitudinally movable powder discharge conduit fitting within said bore and extending from outside said container up through said bore into said dome in intimate contact with said gasket, whereby said gasket shields the clearance space between said tube and the wall of said bore from the access of powder thereto.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 528,417 Duckham Oct. 30, 1894 652,726. Sherburns June 26, 1900 741,116 De France Oct. 13, 1903 358,118 Sticker Apr. 26, 1904 773,852 Cutting Nov. 1, 1904 831,970 Morgan Sept. 25, 1906 847,270 Wise Mar. 12, 1907 864,471 Kelly Aug. 27, 1907 914,105 Boland Mar. 2, 1909 1,054,775 Hull Mar. 4, 1913 1,067,781 Canniff July 15, 1913 1,072,206 Coleman Sept. 2, 1913 1,301,980 Schroeder Apr. 29, 1919 1,364,533 Von Porat Jan. 4, 1921 1,467,488 Muste Sept. 11, 1923 1,535,991 Crom Apr. 28, 1925 1,730,195 Davis Oct. 1, 1929 1,922,330 Robinson Aug. 15, 1933 2,264,108 Anderson Nov. 25, 1941 2,327,337 Burch Aug. 24, 1943