US3149438A - Full nozzle abrasive blast apparatus - Google Patents

Description

P 22, 1964 H. A. MORLEY ETAL 3,149,438

FULL NOZZLE ABRASIVE BLAST APPARATUS Filed Nov. 19, 1962 3 Sheets-Shea: l

P 1954 H. A. MORLEY ETAL $149,438

FULL NOZZLE ABRASIVE BLAST APPARATUS Filed Nov. 19, 1962 3 Sheets-Sheet 2 M mm p 1964 H. A. MORLEY ETAL 3,149,438

FULL NOZZLE ABRASIVE BLAST APPARATUS Filed Nov. 19, 1962 3 Sheets-Shee'l' 3 INVIHVTORS HARM/V0 4 M0845) a *wexw United States Patent 3,149,438 FULL NOZZLE ABRASIVE BLAST APSPARATJ S Harland A. Morley, 944 St., and Mike Benito, 615 Wanaao Road, both of Kailua, Hawaii Filed Nov. 19, 1962, S r. No. 238,813 9 Claims. (Cl. 518) (Granted under Titie 35, U.S. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the. payment of any royalties thereon or therefor.

The present invention relates to abrasive blasting apparatus and, in particular, to blast apparatus employing multiple nozzles for increased coverage.

Abrasive blast apparatus, particularly that used for large surface areas, sometimes employs multiple rather than a single blast nozzle, the obvious advantage being that multiple nozzles greatly increase the blast pattern and consequently expedite and facilitate the cleaning operation. Also, these nozzles sometimes are mounted on movable carriages or platforms on which the operator rides and the platform is movable laterally and vertically along the area to be cleaned. Such arrangements are significant labor-saving devices for which there is an obvious need.

On the other hand, a number of diiiiculties have been experienced which have hindered general acceptance and wide use. For example, the usual multi-blast nozzles are of a type in which the sand and air are delivered to and mixed in a common reservoir from which jet streams are propelled simultaneously from the nozzles all of which communicate directly with the reservoir.

In other arrangements, the operator may be provided with two separate nozzles each having its own supply lines. However in either of these arrangements, individual control of the nozzles is lacking to the extent that the blast stream from one nozzle cannot be cut off independently of the other. Such independent manipulations of the blast from different nozzles is desirable particularly in situations involving spots or areas which present diflicult cleaning problems. The blast from one nozzle must work on this different area for a prolonged period, during which time the other blast or blasts will be cutting away injuriously at the clean metal of surrounding areas.

Another difiiculty with previous multi-blast carriage arrangements, especially those arrangements in which one operator is provided With two nozzles, is that the units are very cumbersome and complex so as to be suitable only for special cleaning operations. Also, as far as is known, such multiple nozzle machines have been of a type utilizing fixed nozzles which lack adequate flexibility of movement and could not be independently manipulated.

It is therefore an object of the present invention to provide a multiple carriage of a type permitting a single operator to independently manipulate and operate plural blast nozzles.

A further object is to provide an unusually simple and easily-controllable blast nozzle carriage permitting the operator complete freedom of movement in directing the plural nozzles at the Work.

A more specific object is to provide a means for mounting such a carriage to permit the operator and the carriage to be transported into work proximity.

Other more general objects are to provide a multiblast carriage which is capable of substantially increasing work production, as well as being safer and relatively more economical particularly in the savings of abrasive and compressed air, this economy being achieved through 3,14%,438 Patented Sept. 22., 1%4

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selective operation of one or the other of the multiple nozzles.

Another more general object is to provide a multi-blast carriage in which the operator is able to apply a personal technique to each nozzle while still retaining the advantage of a machine type operation for production blasting.

Other objects and their attendant advantages will become more apparent in the detailed description which is to follow.

According to the invention, the apparatus includes a rigid frame that carries both the sand and air ducts, the frame, preferably, being partially mounted on a carriage which is movable relative to the work area to transport the frame into Work proximity. The nozzles proper are carried by the sand ducts, and air conduits are employed to deliver compressed air to a mixing chamber of each nozzle.

At least a pair of nozzles is employed, each nozzle having its own sand and air ducts. Of particular significance is the fact that the air ducts themselves are structurally utilized as part of frame, this being achieved by employing rigid air duct sections securely and rigidly held together by an end or cross-piece, the rigid arms, in turn, supporting the heavy sand hoses. Also, the compressed ir for the rigid ducts is delivered through the cross-piece and via a pair of handles carried by the cross-piece. As a further feature, each handle mounts an air control mechanism by means of which the operator can shutdown the supply to one nozzle independently of the other.

Functionally considered, the arrangement is one in which an operator can stand on a platform between a pair of nozzles so as to utilize his personal judgment in directing the blast at desired locations, the arrangement also being one in which the plural nozzles materially increase work production as well as facilitate the. performance of the job. Excellent flexibility is achieved through the pivotal mounting of the carriage as Well as the reciprocating movement of the carrier itself. Also, in a manner which will become more apparent, the mounting of the frame is accomplished in a manner which essentially relieves the operator of the heavy weight of the sand hoses so as to greatly facilitate his mam pulations.

The preferred embodiment of the invention is illustrated in the accompanying drawings of which:

FIG. 1 is a somewhat schematic view illustrating the entire apparatus supported on a forklift truck;

FIG. 2 is an enlarged perspective of a single blast unit formed of a pair of nozzles and their accompanying air and sand hoses;

FIG. 3 is a schematic, partially-sectioned view of the units as shown in FIG. 2, and

FIG. 4 is a view similar to FIG. 3 illustrating another embodiment of the invention differing from the previous embodiment principally in the structure of the carriage employed.

Referring to the drawings, FIG. 1 primarily illustrates the manner in which the present sand blasting equipment is employed. As will be seen, a pair of multiple-blast units 1 and 2 are mounted on a platform 3 which, in turn, is supported on the forward hoist portion 4 of a forklift truck 6, the obvious purpose of so supporting the platform being to permit units 1 and 2 to be elevated and lowered with respect to the work area as well as to permit the platform to be moved laterally by means of the truck. The details of the platform support and the truck are not a part of the present invention. Obviously, other means can be used, one such presently contemplated means being the use of a truck-supported crane to suspend the platform in an elevated position. It also should be understood that the platform itself can be larger or smaller so as to accommodate any number of abrasive blast units.

One operator is employed for each blast unit and as will be described, each operator has full control of a pair of blast nozzles. In using the equipment, the operator stands on platform 3 between a pair of flexible sand hoses 7 and 8, these conduits or hoses extending rearwardly of the operator to a remote supply source which, in the illustrated embodiment, is a sand hopper 9 which also incorporates an appropriate compressed air supply to forcefully transport and drive the abrasive from the nozzles. In a manner which will be understood, a supply of compressed air is directed along with the sand into flexible sand conduits 7 and 8 for transporting the sand through these conduits. In addition, compressed air also is directed into flexible air conduits 11 and 12, this separate supply of air under pressure eventually being directed into a mixing reservoir of the blast nozzles to forcefully drive the sand or abrasive through the nozzles and against the Work. The manner in which the air and sand is mixed in the nozzle is of no particular present concern and, in fact, except for limitations to be subsequently noted, the nozzle structure of the present mechanism can be of any appropriate conventional commercial design.

Other salient features of the invention are more clearly seen in FIGS. 2 and 3 where first it will be noted that blast units 1 and 2 each are mounted on a carriage mechanism 15 that can be moved laterally along platform 3, the platform being provided with rails 16 in the forms of I-beams. The carriage, in turn,.has upper and lower wheels 17 adapted to ride the upper and lower flanges of the I -heam rail (FIG. 3), these wheels being appropriately journaled in an inverted U-shape bracket 18 the top portion of which is welded or otherwise secured to a horizontal base portion 19 of the carriage. Further, base 19 has transverse slots 21 at each of the sides and mounting a pedestal portion 22 supportedly engaged in these slots for the obvious purpose of permitting the pedestal to be adjustably moved. The position of the carriage on the platform can be fixed by. means of a spring-pressed locking plunger mechanism 23 engageable in openings 24 of the rail.

Mounted on pedestal portion 22 is a conduit-support frame 25 the primary function of which is to support the conduits and the blast nozzles, as well as to permit the nozzles to be separatelymanipulated and directed .at operator-selected portions of the area to be cleaned. In greater particular, frame25'is formed of a rigid end or cross-piece 26 from which a pair of rigid air conduits 27 and 28 project in a mutually parallel relationship (FIG. 2). Centrally, conduits 27 and 28. are supported and braced by a cross-bar 29 the outer ends of which each mount a hose clamp ,31 engaging and supporting .sand conduits 7 and 8. It further may be noted in FIGS. 2 and 3 that the leading ends of the sand conduits each mount in the customary manner a nozzle 32 formed with rearward mixing chamber 33. Rigid air conduits 27 and 28 of the frame work each terminate in the mixing reservoir portion of the nozzles so as to drive the sand delivered to these portions forcefully through the nozzles against the work. As already stated, such nozzle struc- .ture is entirely conventional and a number of commercially-available units can be successfully employed.

Another feature is the use of independently operable valve control mechanisms, each of these mechanisms being in the form of a dependently carried handle or pistol grip 34 provided with a hanged trigger 36. Obviously, the arrangement is one in which the operator can encircle the pistol grip and selectively press the trigger for valve control purposes. Also, it is of considerable importance to note that the flexible air conduits 11 and 12 of each unit are coupled into the bottom portion of each pistol grip to communicate the air pressure from the compressed air source through the flexible air conduits and the pistol grip into'rigid air conduits 27 and 28. In the manner indicated in FIG. 3, each pistol grip 34 provides a continuation of the flexible air conduit. A short length of sure release valve mechanism which may be coupled into the air and sand lines in the vicinity of the hopper, the grip portion of this mechanism simply being a remote control of the pressure which in turn operates the valve.v

A number of commercially available valve mechanisms may be employed, these mechanisms being of a type which operatively couple the air pressure into the lines when the back pressure of the lines is at the anticipated maximum. However, when the pressure of the lines is reduced, the valve is constructed to shut down and consequently close off the supply. The present apparatus provides the remote control for such commercial valves, and, more specifically, the control utilizes a short exhaust line 37 (FIG. 3) coupled to the air flow within piston grip portion 34. This exhaust line normally is closed by hinged trigger 36 so as to prevent release of pressure from the grip to atmosphere. However, when the trigger is released, the exhaust line opens to atmosphere to reduce back pressure within the air line and, in turn, to cause the valve to close. To facilitate this operation, each of the valve triggers mounts a small rubber pad 38 which, when the trigger is compressed, effectively seals oil? the exhaust line.

From the description advanced so far, it should be relatively apparent that an operator, standing centrally between sand conduits 7 and 8 and engaging pistol grips 34, one with each of his hands, has full control of the source of air supply as well as the ability to pivot the carriage and also move it along tracks 16 of the support platform. It is equally significant to note that the mounting of frame 15 permits a universal pivotal movement of the carriage so that the operator has universal freedom in pivoting the nozzles to direct the blast in any desired direction. Such a floatable or universal mounting is provided by pedestal portion 22 of the carriage. Preferably, a conventional ball and socket joint is employed the ball portion of the joint being formed on an upwardly extending shaft 41 of the pedestal while the socket is provided in a hub member 42 which, in turn, is welded or otherwise secured to the transverse bar 29 of the hose and air conduit support. Consequently, the entire unit can be pivoted at will by the operator using the ball and socket joint as a fulcrum.

One particular advantage of this arrangement which may not be readily apparent is that the sand hoses themselves are to a large extent self-supporting, particularly when the sand is being transported through them, so as to relieve the operator of a substantial portion of their Weight. Thus, when sand is being transported to these conduits, the conduits become relatively stiff so that the mechanism as a whole be easily pivoted about its universal joint. Of course, when the air supply is cut off by the valve control mechanism previously described, the unit will be inclined to tilt in one direction than the other. To further assist the operator and also relieve him of additional hose weight the rear portion of the hose also is supported on a carriage 50 which, as shown in FIG. 2, mounted on a rear rail 51 of the platform much in the same manner as has been described with respect to the mounting of the hose support carriage 15. In greater detail, rear carriage 50 also has a triangular shaped frame provided with upper and lower wheels 52 riding on an I-beam rail and, secured to the triangular frame, is a flat support plate 53 which has hose clamps 54 at each end for engaging and supporting each of the sand conduits in the manner illustrated. Obviously, when the operator wishes to move the carriage laterally along the platform he simply applies lateral force to his pistol grips and the resulting movement of forward carriage is imparted to rear carriage 50 because of the relatively rigid interconnection of the sand hoses. Also, the rear carriage maintains the hoses substantially in a level position so as to relieve the operator of almost all of their weight.

FIG. 4 represents another embodiment of the invention although this embodiment differs from the previous embodiment principally in the manner in which the air conduit frame is supported. Thus, instead of supporting the carriage directly on a pedestal, this arrangement utilizes a swing-type support 60 cradled in a U-shaped frame 61 which, in turn, is bolted or otherwise secured to bracket 18 of the wheeled portion of the carriage. Swing 60 is formed of a swinging shaft 62 suspended between stationary vertical plates 63 of the U-frame, shaft 62 mounting a bearing 64 providing a pedestal for fioatably mounting a hose-support bracket 66. Bracket 66, in turn, supports the air and sand hoses in a manner similar to cross-bar 29 of the FIG. 2 embodiment. The nozzle mounting is the same as that previously described, as is the use of remote valve control handles 34 and the feed of air through the handles to rigid air conduits 27 and 28.

Our principal difference in the FIG. 4 embodiment is that the hose weight is positively supported by the cradled swing so that it is not essential to employ the rear carriage hose support of FIG. 2. Even so, it again is emphasized that the FIG. 2 embodiment is essentially selfsupporting in a balanced manner during an actual blasting operation. The use of the FIG. 4 embodiment is further facilitated by employing a counter-weight arm 67 supported on a bearing of swing shaft 62. Aside from the dilferences mentioned the structure and operation of the FIG. 4 structure is essentially the same as that previously discussed.

Both embodiments provide a multiple nozzled arrangement in which the nozzles can be easily directed toward the work and also can be independently turned on or off to permit selective use. The lateral movement of the carriage, as well as the free movement of the forklift truck (or its equivalent), will permit the blast units to be moved into work proximity and to be progressed along the work as the cleaning operation is being accomplished. Obviously, any number of blast units can be used.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. Abrasive blast apparatus comprising a plurality of flexible air-pressured abrasive ducts, a nozzle on the forward end portion of each abrasive duct, an air booster duct communicated with each nozzle, a rigid duct-supporting frame, and a horizontally reciprocal carriage pivotally supporting said frame; the frame including a rigid rear end piece, a plurality of rigid substantially parallel arms projecting outwardly and forwardly of said end piece, brace means interconnecting said parallel arms and supporting the forward portion of said abrasive ducts substantially in line with said arms, and a plurality of manually-operable valve control means carried by said end piece for selectivity controlling air supply to each nozzle, said end piece and arms each having air passageways communicating said nozzles with said booster ducts.

2. The apparatus of claim 1 further including a second carriage spaced rearwardly from and horizontally reciprocable with said first carriage, and supporting means carried by said second carriage elevating and carrying rearward portions of said abrasive ducts, whereby said reciprocating movement of the forward portions of said abrasive ducts with said first carriage imparts a similar movement to said rearward duct portions.

3. The apparatus of claim 1 wherein said frame is float ably supported on said carriage, said fioatable support providing a universal freedom of movement for directing the nozzles.

4. The apparatus of claim 1 wherein said carriage includes a stationary cradle portion, and a swinging shaft swingably suspended by said cradle portion, said shaft pivotally supporting said frame.

5. The apparatus of claim 1 further including a platform provided with a horizontal rail section, said carriage being horizontally reciprocable on said rail section.

6. The apparatus of claim 5 further including support means for said platform, said support means being horizontally and vertically movable for transporting the platform into work proximity.

7. The apparatus of claim 2 further including a platform provided with a pair of laterally spaced rail sections, said first and second carriages being horizontally reciprocable one on each of said parallel rail sections.

8. Abrasive blast apparatus comprising a pair of airpressured abrasive ducts, a nozzle on the forward end portion of each abrasive duct, an air booster duct for each nozzle, a rigid frame, and a horizontally reciprocal carriage pivotally supporting the frame, said frame including a rigid rear end piece, a pair of handles carried in a spaced relationship by said rear end piece, a pair of rigid laterally-spaced substantially-parallel arms projecting outwardly and forwardly of said end piece, brace means interconnecting said parallel arms and supporting the forward portion of said abrasive ducts substantially in line with said arms, each of said handles and each of said end pieces and arms being formed with inter-communicating air passageways communicating each of said nozzles with a separate booster duct, and a manuallyoperable control means carried by each of said handles for selectively controlling air supply to each nozzle.

9. The apparatus of claim 8 wherein said control means includes means for varying the air pressure in the air passageway of the handle.

References Cited in the file of this patent UNITED STATES PATENTS 199,576 Rodig Jan. 22, 1878 1,849,384 Ruemelin Mar. 15, 1932 2,063,054 Rosenberger Dec. 8, 1936 2,836,013 Koenig May 27, 1958 2,881,506 Fuchs Apr. 14, 1959 2,953,876 Zieber et a1. Sept. 27, 1960

Claims (1)

1. ABRASIVE BLAST APPARATUS COMPRISING A PLURALITY OF FLEXIBLE AIR-PRESSURED ABRASIVE DUCTS, A NOZZLE ON THE FORWARD END PORTION OF EACH ABRASIVE DUCT, AN AIR BOOSTER DUCT COMMUNICATED WITH EACH NOZZLE, A RIGID DUCT-SUPPORTING FRAME, AND A HORIZONTALLY RECIPROCAL CARRIAGE PIVOTALLY SUPPORTING SAID FRAME; THE FRAME INCLUDING A RIGID REAR END PIECE, A PLURALITY OF RIGID SUBSTANTIALLY PARALLEL ARMS PROJECTING OUTWARDLY AND FORWARDLY OF SAID END PIECE, BRACE MEANS INTERCONNECTING SAID PARALLEL ARMS AND SUPPORTING THE FORWARD PORTION OF SAID ABRASIVE DUCTS SUB-

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