US2837874A

US2837874A - Sand blasting apparatus

Info

Publication number: US2837874A
Application number: US591967A
Authority: US
Inventors: Edgar D Hunter
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-06-18
Filing date: 1956-06-18
Publication date: 1958-06-10
Anticipated expiration: 1975-06-10

Description

June 10, 1958 D. HUNTER 2,337,874

SAND BLASTING APPARATUS Filed June 18, 1956 2 Sheets-Sheet 1 INVEN TOR. 42%? fl/Waz I True/M17 June 10, 1958 E. D. HUNTER 2,837,874

' SAND BLASTING APPARATUS Filed June 1a, 1956 2 Sheets-Sheet 2 20 INVENTOR.

United States Patent 2,837,874 SAND BLASTING APPARATUS Edgar D. Hunter, Baltimore, Md.

Application, June 18, 1956, Serial No. 591,967

4 Claims. (Cl. 51-8) The present invention relates to an improved sand blasting apparatus, particularly 'to a type that is normally manually operated.

The primary object of the invention is to provide means for boosting the sand from a point adjacent the supply along an exhaust hose to the point of discharge thereof.

Another object of the invention is to provide an improved nozzle in such an apparatus'in which the air is controlled .to both the booster and the air outlet end of the nozzle by a single valvecarried within or adjacent the nozzle.

A further object of theinvention is to provide a methd of continuously moving auniformmixture of air and sand through the outer end of the nozzle.

While several objects of the invention have been pointed out, other objects including its uses and advantages will appear more readily as the nature of the invention is more fully described, consisting of its novel feature, arrangement and combination of parts as shown in the accompanying drawings and described in the written specification. In the drawings:

Figure l is a fragmentary view in elevation of the apparatus.

Figure 2 is a fragmentary view in elevation of the particular type of receiving end for the sand which may be inserted in an ordinary sand pile. V

Figure 3 is an enlarged sectional view of the improved nozzle.

Figure 4 is an enlarged sectional view of the sand receiving end of the apparatus when the apparatus is used in connection with a hopper.

Figure 5 is a sectional view of the type of sand receiving member as shown in Figure 2.

Figure 6 is a sectional view taken along lines 6-6 of Figure 5.

In referring to the drawings like numerals are used to indicate like and similar parts throughout the several views.

Referring in particular to Figure 1, there is provided a hopper 10 supported by a suitable frame 11. Extending below the hopper 10 is an outlet for the sand 10' and connected to the outer end ofthe portion 10' is a booster for the sand The booster is provided with an outer 'casing 12 and connected to the outer end of the casing 12 is a convenient coupling 13 which is in turn connected with a hose member 14. The hose member 14 leads to the nozzle 15 and is connected thereto by a suitable coupling member 16.

Within the housing 12 there is an. air jet 20. This jet is directed in the direction the sand is to take through the hose 14 and eventually to the nozzle. Air is supplied to the jet through the pipe 21 at a reduced pressure from that carried in the air hose 27 leading to the nozzle. The nozzle as shown best in Figure 3 is provided with an outer curved housing 22. At one end of the housing there is a rubber, or plastic lined jet 23, which is attachable to the end of the housing 22 by the member "ice tending through the outer bend of the housing or casing 22 which is in line with the jet 23. i This member 25 is provided with a second smaller jet member 26 similar to the one shown at 23 which extends within the nozzle in rear of the jet member 23. Leading to the member 25 is an air supply hose 27 Positioned within the member 25 is a valve 28 which is operated by a lever 29. Extending through the casing of the member 25 is an opening 30. This opening is connected with an air hose 31 which in turn is connected with the pipe 21 leading to the booster jet 20 in the booster. The

flexible hose lines

14, 27 and 31 are connected by suitable bands 32 in order that they may behandled as a single group.

It will be noted that the opening 30 leading to the booster hose 31 is located outwardly from the valve 28, therefore when the valve 30 is closed, air is cut ofi from both the nozzle and the booster by this single valve. This is' very convenient for the operator and naturally follows that an operator may work more efficiently with such an apparatus.

The air carried by the main air line 27 is substantially A greater than the air permitted to pass through the booster jet 20. This is regulated by a suitable regulating valve 33 where these pressures may be proportioned.

When the apparatus is in use, the hose leading from the nozzle are connected as shown in Figure 1, that is, the air line 27 is connected with a suitable air supply (not shown), the hose 14 is connected with the outer end of the booster and the hose 31 is connected with the pipe 21 leading to the booster jet.

When the device is being used in an ordinary pile of sand it takes theform as shown in Figure 2, that is, the member 12' is inserted into the sand pile 35 as shown by the dotted lines at 12". In order to keep the receiving end of this form of the apparatus in the proper position, there is provided a foot member 36 which will prevent the casing 12 from rotating and in proper operating position.

Whichever receiving means is used, the jet operation of the apparatus is substantially the same. Taking for example, the preferred form as shown in Figure 1, the hopper 10 is first filled with sand, and sand is fed by gravity down through the neck 10 of the hopper to the booster. Within the booster shell 12 there is a jet 37 which directs a blast of air toward and along the hose at a reduced pressure by means of the pressure reduction valve 19. The air moves along the hose 14 toward the nozzle. This blast of air picks up the sand and keeps it in suspension until it has reached the nozzle where it is mixed with the blast of air emanating from the member 26 at a much greater velocity. With this increased velocity this mixture of sand and air pass through the outer jet member 23. The booster prevents bunching of the sand at any one place as it moves through the hose 14. lt gives a much steadier and regular mixture of sand and air to the surfaces being blasted than has been done herebefore.

In using the sand receiving member as shown in Figure 5 air moves through the jet 20 at a reduced pressure by virtue of the control valve 33 and acts in the same manner on the sand as has just been described for Figure 1. The device may be used with a stationary installation or it may be of a portable nature. Likewise, the apparatus may be used with a hopper, or it may be used with a mound of sand located over the receiving end of the apparatus, as shown in Figures 2 and 5.

While the invention has been described in detail it is not intended as a limitation, as the scope of the invention is best defined in the appended claims:

What is claimed is:

l. A sand blasting apparatus having a sand receiving Patented June 10, 1,9558

3 element and a nozzle for dispensing the same having an air cut-off valve carried thereby, the sand receiving element having positioned therein an air jet directed toward its outlet, a flexible air supply line leading directly to the said nozzle from a suitable supply source, a, flexihousing having an inlet in one portion thereof for re ceiving the sand conveying means and an opening in another portion of the. nozzlefto. receive an outer blasting j'et', a valve in' said. air admitting means for control-' ling the flow of air therethrough, a'second inner air jet within the hollowhou'sin'g 'connected wi th the air admittin'g' rneans and directed centrally and rearwardly of the outerjet, an opening in the air admitting mea ns on the opposite side of the valve from the second mentioned inner jet adapted to be connected to an airline leading to the outside of the nozzle housing.

3. A sand-blasting apparatus having a sand receiving element and a nozzle for dispensing the same, a conduit connecting the sand-receiving element with the nozzle, a pressure air supply conduit leading to the nozzle for forcing the sand therethrough, an air control valve associated with the nozzle for opening and closing the air supply conduit, an air sand booster adjacent the sand-receiving element for assisting the movement of the sand through the conduit connected between the sand-receiving element and the nozzle, a separate air conduit leading from the nozzle to the sand air booster, the separate air conduit having one end connected to the nozzle beyond the air control valve and its opposite end connected with the sand air booster for supplying air to the booster only when the air control valve is open to allow air to flow through the nozzle.

4. A sand blasing apparatus-having a sand receiving element and a nozzle for dispensing the same, a conduit connecting the sand receiving element and the nozzle, an air supply conduit leading to the nozzle from an air supply under pressure, an air control valve associated with the nozzle for opening and closing the air supply passing through the nozzle, an air sand booster positioned adjacent the sand receiving element adapted to direct a jet of air in the direction the sand is moving through the conduit leading from the sand receiving element to the nozzle, means for reducing the air pressure entering the sand booster relative to the air pressure moving through the nozzle, an air conduit extending from a point beyond the air valve in thenozzle to the sand booster for supplying air to the air booster jet only Whenthe air control valve is open to allow air to flow through the nozzle.

Anderson June 26, 1951