US3132449A - Sandblast apparatus - Google Patents

Description

y 12, 1964 P. H. WILLIAMS 3,132,449

SANDBLAST APPARATUS Filed May 21, 1963 3 Sheets-Sheet 1 Fig.

Philip H Williams INVENTOR.

BY w

y 12, 4 P. H. WILLIAMS 3,132,449

SANDBLAST APPARATUS Filed May 21, 1963 3 Sheets-Sheet 5 Philip H. Williams IN VEN TOR now W 15M United States Patent Ofitice 3,132,449 Patented May 12, 196% 3,132,449 SANDBLAST APPARATUS Philip H. Williams, San Jose, Calif., assighor to Victor C. Arispe, Sequel, Calif. Filed May 21, 1963, Ser. No. 281,899 9 Claims. (CL 51-43) This invention comprises a novel and useful sandblast apparatus and more particularly pertains to an apparatus of the same general type but constitutes an improvement over the sandblast apparatus disclosed in the prior patent of Victor C. Arispe, Patent No. 2,565,341, issued August 21, 1951.

There are conventional known types of sandblasting equipment in which the castings or work to be sandblasted are placed in a cylindrical barrel or drum and tumbled about therein during rotation of the drum about a central horizontal axis. In such equipment, a sandblast nozzle positioned inside the rotating drum and directs its spray upon the work or articles tumbling about within the drum, and in order to seek a more uniform treatment of the work by the blast, the sandblast nozzle is given an oscillatmg movement in order to cause the sandblast to travel along the length of the drum and the work therein. It is with apparatuses of this type that the present inventron is particularly concerned and presents improvements and advantages asto structure and operation thereover.

The chief difficulty encountered in sandblast apparatuses of the above mentioned type is the lack of uniformity or evenness in the sandblasting treatment of the workpieces and the lack of uniformity of the pattern of the sandblasting upon the workpiecesi Usually, these disadvantages arise from lack of uniformity in the time during which the sandblast is applied to different portions of the workpieces duringthe oscillatory path of travel of the sandblast nozzle. A further difficulty rises from a lack of the ability .to precisely adjust and regulate the angle or" the sandblast throughout a wide range with respect to different workpieces in order to obtain a uniform treating etfect thereon. As a result of these dithculties encounteredin prior apparatuses, there results a sandblasting operation which is not uniform as toits treatment of the entire surface of the workpieces, requires an excessive amount of time to complete the blasting operation and results in excessive costs therefor. i

It is therefore the primary purpose of this invention to provideia sandblast apparatus which will effectively overcome the above mentioned and other disadvantages oi prior sandblast equipment.

Basically, the essence of this invention resides in the provision of an apparatus in which the sandblast jet can be easily and quickly moved into or out of the rotating work housing or shell together Withan improved means for precisely and with celerity adjusting the positionof the sandblast jet Wllhfe SpBCt tO the workpieces within the housing throughout a Wide range of adjustment in order to obtain -the optimum Work-ing positionot the sandblast jet with respect tothe given workpiece or workpiecesfwithinthework hou 'ng.

More specifically, ove 5nd advantageousofeatures of this invention reside in:

plate whereby to effect with celerity and certainty the adjustable positioning of the jet nozzle throughout a wide range of positions within the work housing to thereby obtain a wide selection of patterns of abrasion by the sandblast jet. 7

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a top plan view of one suitable embodiment of the sandblast apparatus incorporating therein the principles of this invention;

FIGURE 2 is a side elevational view, upon an enlarged scale, of the apparatus of FIGURE 1;

FIGURE 3 is an end elevational view taken on the left end of FIGURE 2 with parts being broken away;

FIGURE 4 is a vertical central sectional view taken upon an enlarged scale and substantially upon the plane indicated by the section line d-4 of FIGURE 1 and with parts being broken away;

FIGURE 5 is a vertical transverse sectional view taken substantially upon the plane indicated by the broken section line 5-5 of FIGURE 4;

FIGURE 6 is a detail view in horizontal section and upon an enlarged scale, being taken substantially upon the plane indicated by the section line 6-6 of FIGURE 4 and showing in particular the mounting and oscillating means for the jet nozzle in the jet housing; and

FIGURE 7 is a further detail view in vertical section being taken upon an enlarged scale substantially upon the plane indicated by the section line 77 of FIGURE 4 and shows certain details of the adjusting and mounting mechanism of the jet housing upon the adjustable stationary work housing closure plate of the device. I

In the accompanying drawings there is disclosed by way of example only one preferred embodiment of an apparatus for carrying out the principles of this invention including its novel method of operation. The apparatus, indicated generally by the numeral 10 consists of a suitable support structure which includes a supporting .rail 1); which is associated with astationary outer casing or housing lid which constitutes an enclosure of the sanoblast apparatus during its sanding operation. Referring especially to FIGURE 4 it will be observed that the support means 12 comprises ahorizontally extending overhead rail which may be of I-beam configuration as shown and which extends into the stationary outer casing or housing 14. Supported upon this beam for movement longitudinallytherealong is a sandblasting element indicated gen support rail extending into the outer casing 1d at the lower portion thereof with the apparatus in being mounted upon and projecting upwardly above the support rail. "In any event, it is essential for the purposes of this invention that the apparatus it shall be capable of movement longitudinally upon its support means 12 so that it may be moved into and out of the stationary outer casing 1 i With continuing reference to FIGURES 4 and 5 it will be observed that the, apparatus I6 includes a carriage which is'rnounted by upstandingbrackets 2t? and roller 22 upon therail 12 for movement therealong. Inasmuch as the structural details of the carriage in itself may be varied widely within the principles of this invention and in themselves form no part of the invention set forth 4 and claimed hereinafter, and will be readily understood 3 by those skilled in the art, a further description and showing thereof is deemed to be unnecessary.

The outer housing 14 is provided with what may be termed its inner end with a-stationary end wall 24 while its other end has an end wall 26 provided with a relatively large opening 28 therein for a purpose to be subsequently set forth. Received in the lower end of the outer casing between the Walls 24 and 26 is a sand collecting device which may be in the form of a bin or container 30 open at its top and into which the sand of the sandblasting operation as set forth hereinafter drops and is collected, suitable conduit means as at 32 being provided for effecting a continuous withdrawal of the accumulating sand for reuse by the sandblast nozzle as set forth hereinafter.

Suspended from the carriage 18 as by means of a single bracket or support arm 34 is an axle 36 journaled in a bearing sleeve 38 of the arm 34 and which axle is rigidly secured to and constitutes a support for the closing end wall 40 of a rotatable cylindrical work housing or tumbling barrel 42 which is open at its right end as viewed in FIGURE 4. It will thus be observed that the barrel is supported cantilever fashion from the bearing sleeve 38 and the support arm 34 by the axle 36. A plurality of apertures 44 which are preferably evenly and uniformly distributed over the entire cylindrical circumference of tumbling barrel or drum 42 are provided for allowing the escape of the sand and air from the interior of the turnbling barrel.

The tumbling barrel has a horizontal axis which is the axis of the shaft 36, about which the tumbling barrel rotates.

In order to effect this rotation there is preferably provided a source of power such as an electric motor 46 mounted upon the support carriage 18 and which drives by means of a pulley 48 and a belt 50 a driven pulley 52 secured to the outer end of the axle 36.

Air which conveys and discharges the sand of the sandblast mechanism is permitted to escape from the interior of the stationary outer casing 14 as by means of a sand discharge or outlet pipe 54.

In order to further support and guidably mount the open or right end of the tumbling barrel or drum 42, there is provided journaling means therefor such as a stationary support member or plate 56 carried dependingly by the support carriage 18 and which has a plurality of rollers 58 rotatably journaled upon a peripheral flange 60 of the member 56.

These rollers engage against an annular track 62 secured to the periphery of the drum 42.

A further stationary bearing support plate 64 is carried by the support structure 18 and has journaled thereon a series of rollers 66 which engage and rotatably support the exterior surface of the drum. It will thus be apparent that the drum is rotatably journaled for rotation about its longitudinal axis while being dependingly secured to the support carriage 18 for movement therewith along the track 12 into and out of the outer casing 14.

A very important feature of this invention resides in the relative proportions of the tumbling barrel. Ordinarily, tumbling barrels are relatively long compared to their diameter. However, it is an important feature of this invention that the tumbling barrel is of relatively greater diameter than its length so as to reduce the axial extent of the barrel and of the stationary outer, casing 14. As a result of these proportions, there is obviously relatively less travel required of an oscillating spray nozzle longitudinally of the barrel in order to project the sandblast uniformly over the entire surfaces of the various articles received in the tumbling barrel.

With continuing reference to FIGURE 4 it will be noted that the end wall 24 is provided with a central opening 68 therethrough through which is received a generally cylindrical sleeve 70 projecting inwardly of the outer casing 14.

Adjustably secured to the end Wall 24 is a mounting assembly indicated generally by the numeral 74, to be hereinafter described, and by means of which there is supported a horizontally extending jet housing 76 which is preferably of cylindrical configuration and projects into the interior of the tumbling barrel for a considerable distance therein. As will be best observed from a consideration of FIGURE 4 in conjunction with FIGURE 6, the housing 76 has end closures 78 and 80 at its opposite ends and is provided with a longitudinally extending slot or opening $1 in one side thereof. Mounted within this housing and positioned therein for discharging the sandblast through the opening 81 with various controlled paths of movement is a jet nozzle assembly indicated generally by the numeral 82. This assembly includes a jet nozzle 84 of any known and conventional type which in itself forms no part of the present invention, and which has a discharge nozzle 86 directed through the slot 81 for discharging the sandblast upon the objects within the interior of the tumbling barrel. The jet nozzle 84 is supplied with compressed air as through a flexible conduit 87 and with sand as through the flexible conduit 83, each of these conduits extending through the end Wall St and being connected to a suitable source of compressed air, not shown, and a suitable source of sand such as the hopper 90 mounted upon any suitable support means such as a bracket 92. It Will be understood that the sand conduits 32 previously mentioned and extending into the receptacle 30 remove sand therefrom and discharge it by any suitable means, not shown, and as by a conduit 94 into the interior of the sand tank 90 from which the conveying air may escape therefrom as by a conduit 94.

Means are provided for effecting various controlled movements in a cyclic manner to the nozzle assembly in order to vary the direction of its sandblast. For this purpose, there is provided a supporting bracket assembly 96 which may be suitably carried by the end wall 24 and upon which is mounted a source of power such as electric motor 98 which through the reduction gearing assembly 100 imparts rotation to a crankshaft 102 having a crank 104 thereon. As shown in greater detail in FIGURE 6, the crank is provided with a connecting rod 106 which is pivoted to the end of a reciprocating actuating shaft 108 journaled in a pair of fixed bearings 110 and 112 provided upon the interior of the housing 76. The jet nozzle 84 is itself fixedly secured to and carried by a reciprocating supporting and driving shaft 114 which is journaled in the supporting bearings 116 and 118 likewise provided in the interior of the housing 76. An arm 120 which is fixedly but adjustably secured upon the shaft 108 as by means of adjustable collars 122 is in turn fixedly secured to the shaft 114 whereby the latter will be reciprocated in its bearings in response to reciprocation of the shaft 108. In this manner, controlled reciprocation can be imparted to the nozzle 84 to cause the latter to travel in a rectilinear path in a direction which is parallel to the horizontal axis of the tumbling barrel in order that the spray from the nozzle may be uniformly directed along the length of the barrel. It will be appreciated that any desired means can be provided for varying the speed of this reciprocation, while the adjustable connection of the arm 120 to the shaft 108 enables prev cise variation of the amplitude of reciprocation of the nozzle in the housing 76.

In order to effect rotational adjustment of the nozzle 84 and thus of the directionof the sandblast therefrom within the interior of the tumbling barrel 42, means are provided for rotating the entire jet assembly and its housing 76 about its axis and within its mounting means 74. r

This mounting means, as shown best by reference to FIGURE 7, consists of a base mounting plate which may be circular as shown at and which is rotatably journaled in and secured by a pair of arcuate retaining brackets 132 against the face of the end wall 24 in a arsaaas manner to completely overlie and close the opening 68 in this end wall. The base plate 13% is itself provided with a circular opening 134 therein and this latter opening is also covered by an adjusting plate 136 which is rotatably retained upon the base plate 130 as by arcuate brackets 138. Finally, the cylindrical jet housing 76 is provided with an annular externally projecting mounting flange 140 which completely overlies the opening 142 i in the plate 136 and which flange hill is rotatably retained in arcuate retaining brackets 143 upon the plate 134.

It will be observed that various fastening means such as the bolts Md, 1% and MS of the brackets 132, 138 and 143 respectively are employed to both retain the respective supporting plates in position and to also lock these plates in rotationally adjusted position. It will be observed that the plate or flange 140 and the opening 141 which is covered by this fiange are eccentrically disposed with respect to each of the plates 1% and 13%. Consequently, independent individual rotational adjustment of any of these plates will produce a corresponding travel of the jet assembly housing 74: in a circular path of travel within the interior of the tumbling barrel. As will be evident, various combined motions can be given to the jet housing 76 by corresponding joint adjustments of the various mounting plates. For exarnple, straight line travel in a vertical or horizontal plane can be readily imparted to the jet housing and thus to the jet nozzle carried thereby. By means of various manipulations of the mounting plates either singly or jointly a very wide variation both of the position of the nozzle within the interior of the tumbling barrel and also the direction of the path of the sandblast from the nozzle is obtainable. This enables the nozzle to be positioned at the most effective location for eliective sandblasting of the various articles placed in the tumbling barrel.

The method of operation performed by this invention is as follows. With the apparatus supported by its supporting carriage T3 at a position outside of the stationary outer casing lid, ready access can be had to the open right end of the drum 42 for the introduction of or the removal of articles. With the drum loaded with articles to be sandblasted, the support carriage is then moved into the interior of the stationary casing 14. it will be observed that during this operation the apparatus will move through the opening 28 in the end Wall 26 which opening will then be closed by the closure plate 29 which is fixedly carried by the support carriage 1th and will be moved into closing engagement with the opening 23 of the Wall 26. At the same time, during this movement, the open right end of the tumbling barrel is moved towards the stationary closure carried by the wall 24 and the stationary jet housing assembly supported thereby. This enables the jet housing assembly to be automatically and readily removed from the interior of the tumbling barrel each time the latter is withdrawn from the stationary casing 14, so that ready access can be had to the jet housing assembly for inspectionof or servicing of any of its components and for further rendering the full area of the open end of the tumbling barrel available for access to its interior.

With the apparatus in the position shown in FIGURE 4, and the tumbling barrel now moved into the interior of the stationary casing 14, the open end of the drum will now be closed by the closure member carried by the stationary outer casing wall 24. Thus, the interior of the drum is sealed except for the openings 44 which permit the escape of sand and air from theinterior of the drum during the operation of the sandblasting spray.

Continuous rotation of the drum by the power source carried by the support carriage 18 presents the articles therein in various attitudes for treatment by the sandblast. Further, the latter by virtue of its combined rectilinear reciprocation through the motor 98 and the crankshaft 102 travels continuously throughout the major length of the drum. At the same time, the angle of impingement of this spray upon the articles of the drum can be precisely and widely varied in accordance with the mounting means 74 as previously described.

As emphasized hereinbefore, the drum is of relatively large diameter as compared to its length. This important feature of the invention produces a number of advantages as follows:

(1) The enlarged diameter, in contrast with the more conventional proportions of tumbling barrels, afifords suilicient room within the drum for positioning the jet assembly, for readily adjusting it and for the insertion or Withdrawal of the assembly as may be desired.

(2) It enables the jet assembly to be disposed perpendicularly of the face of the work, an arrangement im possible with the conventional arrangement of a jet discharging through and into the open end of the drum.

(3) The greater diameter and decreased length provide a drum capacity equal to that of a longer drum of con ventional proportions but insures that the abrasive spray Will cover and treat more effectively and efhciently a greater amount of material in a unit of time. As a result of the uniformly greater concentration or" the spray over the length of the Work there are less dead spots or thinly sprayed areas upon the work, effecting a higher efficiency of operation, increased production and lower costs.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A sandblast apparatus comprising a support structure, a work housing consisting of a drum having an open end and a central horizontal axis, means mounting said housing for rotation about said axis, means for rotating said housing about said axis, a closure for the open end of said housing and mounted upon said support structure, means effecting relative movement of said housing toward and from said closure whereby the latter will selectively close and uncover said open end, a horizontally extending jet housing carried by and extending through said closure for relative movement of said jet housing in a direction axially of said Work housing, a sandblast jet mounted in said jet housing and having a jet nozzle positioned to discharge a sand spray transversely of said work housing, means supplying sand and air under pressure to said jet nozzle, means for adjusting said jet within said work housing selectively, both vertically and horizontally While maintaining the central horizontal axis of said jet housing in parallel position.

2. The combination of claim 1 wherein said work housing has a closed other end, an axle securedto said closed end to said work housing mounting means including a journal receiving and supporting said axle, said Work housing rotating means being connected to said axle for rotating the latter.

3. The combination of claim 2 wherein said drum consists of a perforated cylinder and is of greater diameter than length.

4. The combination of claim 1 wherein said suppor structure includes a stationary casing, said closure comprising a stationary member carried bysaid stationary casing and operable to respectively uncover and close said open end upon movement of said drum away from and towards said closure.

5. The combination of claim 1 wherein said jet housing has-a slot in one side thereof, said jet nozzle being positioned for discharging a blast of sand through said slot and against the surface of articles in said drum, means for reciprocating said jet nozzle horizontally and axially in said jet housing.

6. The combination of claim 1 wherein said jet housing adjusting means comprises a series of mounting plates disposed in flat, side by side engagement and rotatably journaled upon each other for relative rotation and having registered openings through which said jet housing projects into the interior of said work housing, means for rotatably journaling one of said mounting plates upon said closure, said jet housing being carried by another of said mounting plates and being disposed eccentrically of the remainder of said mounting plates.

7. A sandblast apparatus comprising a tumbling barrel rotatable about a horizontal axis and having an open end, a stationary housing for enclosing said barrel and having a closure for said open end, a track extending into said stationary housing, support means movably mounted upon said track for movement into and out of said stationary housing and rotatably journaling said barrel, a sandblast jet assembly including a jet nozzle carried by said closure for projection into said barrel through said open end, means carried by said support means for effecting rotation of said barrel, means carried by said closure for efiecting reciprocation of said jet nozzle in said barrel.

8. The combination of claim 7 including means mounting said jet assembly upon said closure for selective adjustment in both vertical and horizontal directions relative to the aXis of said barrel.

9. The combination of claim 8 wherein said adjusting means enables movement of said jet assembly for straight line motion.

References Cited in the file of this patent UNITED STATES PATENTS 1,476,619 Kemp Dec. 4, 1923 1,710,166 Hull Apr. 23, 1929 1,948,873 Vessey Feb. 27, 1934 2,565,341 Arispe Aug. 21, 1951

Claims (1)

1. 7. A SANBLAST APPARATUS COMPRISING A TUMBLING BARREL ROTATABLE ABOUT A HORIZONTAL AXIS AND HAVING AN OPEN END, A STATIONARY HOUSING FOR ENCLOSING SAID BARREL AND HAVING A CLOSURE FOR SAID OPEN END, A TRACK EXTENDING INTO SAID STATIONARY HOUSING, SUPPORT MEANS MOVABLY MOUNTED UPON SAID TRACK FOR MOVEMENT INTO AND OUT OF SAID STATIONARY HOUSING AND ROTATABLY JOURNALING SAID BARREL, A SANDBLAST

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