US2255660A - Material projector - Google Patents

Description

Patented Sept. 9, 1941 UNITED STATES PATENT OFFICE MATERIAL PROJECTOR Owen J. Gartner, Cleveland, Ohio Application August 26, 1939, Serial No. 292,117

3 Claims.

My invention relates to material projectors and more particularly to a rotary means for projecting abrasive materials.

It is one of the objects of my invention to reduce the initial and maintenance costs of abrasive projecting machines by constructing a machine of this type, in which the destructive action of the abrasive material to the parts of the machine is reduced to a minimum.

Another object of the invention is to construct a machine of the above named character in which the abrasive material is fed to a rotor near its outer circumference and then delivered from the rotor at a point near its hub or axis.

A further object is to provide a rotor having the general form of a truncated cone and havin a plurality of guide channels for feeding the abrasive material from a point near its larger diameter to a point near its smaller diameter.

Another object is to provide a rotary projector for materials such as abrasives, which is simple in construction, inexpensive to manufacture and maintain, and easy to operate.

A still further object resides in the novel mounting or support for the rotor whereby a stream of abrasive may be easily directed in any desirable direction.

Other objects and advantages of my invention will become more apparent as the following description of one embodiment thereof progresses, reference being made to the accompanying drawing, in which like reference'characters are employed to designate like parts throughout the same.

In the drawing- Figure 1 is a side elevation of a machine embodying my invention, some of the parts being shown in section;

Figure 2 is a top view, slightly enlarged, of the rotor element illustrated in Figure 1;

Figure 3 is a perspective view of the rotor element illustrated in Figures 1 and 2; and

Figure 4 is a perspective view of a modified form of rotor.

In sand or abrasive throwing machines, it has been the custom to feed the abrasive material to or through the hub of a wheel rotating at high speed, and to utilize the action of centrifugal force to project the material from the wheel at its outer periphery against an object to be I treated.

Among the chief objections to this type of projector is the fact that the abrasive particles cause extremely high wear, and destroy the blades of the wheel in a few hours time, necessitating stopping the machine for repair and replacement of blades, thus resulting in loss of considerable time and high operating expense. Increased internal resistance generated in this type of machine obviously requires greater horsepower to overcome such resistance. Furthermore, with this type 0f machine, it is extremely difiicult, if not impossible, to properly concentrate and control the stream of abrasive material to the desired areas. 7 By my invention, I have overcome these difficulties and have provided a machine for projecting all classes of fluids in such a manner that excessive wear in the machine is eliminated.

While I have illustrated in the drawing a form of my invention which is particularly adapted for use n projecting abrasive material such as metal abrasives or sand, it is to be understood that I do not intend to be limited to this application of the invention, since it is equally well adapted to projecting other materials in the fluid or semifiuid state.

An electric motor or other power plant I is mounted upon a plate 2. The plate 2 is swiveled for swinging movement upon a shaft 3 carried by suitable support (not shown). The upper casing member 4 is removably mounted on the plate 2 below the shaft 3 by means of the bolts 5. A lower casing member 6 is removably attached to the casing 4 by a series of bolts 1.

From the drawing, it will be seen that the motor shaft 8 is in axial alignment with the axis of the assembled casing members 4 and 6. The drive shaft 8 is connected through a suitable coupling member 9 with a driven shaft H) extending into the casings 4 and 6, there being providedwith a thrust bearing II and a roller bearing l2 in the bearing support 13.

The shaft in extends axially downwardly from the bearings II and I2 and through a rotor M. The rotor or impeller I4 is locked to the shaft I0 at l5 by means of a lock nut l6 threaded on the lower end of the shaft ID.

A driving connection between the shaft l0 and V the rotor I4 is provided at IT. The member I! is keyed to the shaft at IB and is provided with a lower transverse rib H! which is adapted to seat in the slot 20 of the rotor 14 when the parts are assembled as shown.

From the above, it will be clear that the bearings H and I2 .are readily accessible from the upper casing 4 by removing the cap 2|, and that the, rotor I4 is readily reached by removing the nuts l6 and I to release the lower casing 6 and the rotor I4. It is important that these parts be easily accessible for replacement, although by to traveltoward the axis of the rotor point near; its periphery.

my invention replacement will be much less ,fre-

Referring now more particularly to Figures 2 and 3 of the accompanying drawing, I will de- 7 l5 scribe the construction of the rotor l4 more in detail.

This element M of the machine is of truncated cone form and is designed to impart a velocity to the material by high speed rotation of the rotor l4 and at the same time to guide the material from the point where it is received into the rotor l4, thatis near its largest diameter to the delivery end of the rotor which is at its smallest diameter,

The rotor 14 is preferably formed by casting and in the form illustrated-in Figures 2 and 3 is provided with a plurality of helical guides 24 substantially L-shaped in cross-section, each opening outwardly throughout its length at 25, and each having a portion recessed at- 26'into the body of the rotor M. The rotor i4 is provided with an axial bore to receive the shaft I0 and with aslot in its upper portion to receive the key 1 of the locking member l1.

It is to be noted that by my invention the material to be projected is first introduced into the 1 guides 24 of the rotor Hl at the upper end at a point near the greatest diameter of the rotor l4 and that the material travels along the helical guides24- and recesses 26 as the rotor I4 is revolved at high speed to be delivered from the f rotor Met a point near the smallest diameter of the rotor M. In effect, the material is caused I 4 from a By this design, I have found that excessive wear caused by the abrasion of particles travel- 3 ing at high speed is greatly reduced, since the 1 manner of conveying the material through the rotor as contemplated by my invention reduces 1 to a great extent internal'abrasive wear in the 1 machine, and at the same time tends to build up 3 a strong projecting pressure upon the material.

1 1 In the 'machines of the prior art of which I am I aware the material is fed into or near the hub of a'high' speed wheel and is allowed to impinge upon blades substantially radially disposed with- It is clear that in these machines of the prior art, the parts and more particularly the blades have a useful life of only a few'hours'at'best.

But, as has been described above, my invention has eliminated this'excessive wear. I provide a removable and interchangeable nozzle 21 which 1 may be attached to the lowercasing 6 by means of bolts 28. This nozzle is provided with an outj let 29 through which a swirling jet of the material is delivered. a The inner wall of the nozzle" 21 is built :up .annularlyat. 30 to resist wear since there is considerable abrasive action of the material with the inn'erwall of the nozzle 2'1 as the former passestherethrough.

in the wheel, and thence travel outwardly along the blades to be delivered from some point on the periphery of the wheel.

In Figure 4 I have illustrated a modification of the means for guiding the material through the rotor. In this form the rotor 32 is formed with a plurality of openings 3| passing from a point near the largest diameter of the rotor to a point near its smallest diameter and axially of the rotor. It is to be noted that in this form of the rotor the openings or ducts 3| are entirely enclosed within the rotor, thus confining contact of the material as it passes through the rotor to, the Walls of the openings. It is to be further observed that the ducts 3! are substantially straight as distinguished from the channels shown in Figures 1 to 3, and that their axes are disposed at an angle of about thirty degrees to the axis of the rotor.

It is to be understood that while I have shown in Figures 1 to 3 and Figure 4 certain forms of channels or guides through the rotor, I do not wish to be limited to the specific cross-sectional shapes of these channels, since I may equally Well employ channels having modified crosssections, without impairing the efficiency of the machine.

, Various changes in the details of construction and arrangement of parts may be made without departing from the spirit of the invention.

1 claim:

1. In a material-projector, a cylindrical casing, a pivoted support for the casing, said casing being movable about a horizontal axis and having. a material charging inlet at one end, a discharge nozzle at the other end of the casing, said nozzle having a restricted" discharge opening co-axial with a rotor, a rotor in the casing, means for rotating said rotor in the casing at high velocities, said rotor having a plurality of helical passages communicating with the casing inlet andv with the-nozzle, whereby material entering the inlet will be discharged in the form of a concentrated stream through the nozzle at high velocity.

2; In a material projector, a cylindrical casing, a pivoted support for the casing, said casing be-' ing movable about a horizontal axis and having a material'charging inlet at one end, a discharge nozzle atthe other end of the casing, said nozzle.-

having a restricted discharge opening co-axial with arotor, a rotor in the casing, means for rotating said rotor in the casing at high'velo'ci ties, said rotor having a plurality of passages arranged helicallyofthe rotor and communicating.

with the casing inlet and with the nozzle, Where 3. In a material projector, a cylindrical casing,"

a pivoted support for the casing, said casing being movable about a horizontal'axis' and having a material charging inlet at one end, a discharge nozzle at the other end of 'the casing, said nozzle having a restricted discharge opening co-axial with a rotor, a rotor in the casing, means for rotating said rotor in the casing at high veloci t ties, said rotor havinga plurality of helically arranged passages communicating with the'casing inlet and with the nozzle,'whereby material entering the inlet will be causedto travelfin adir'ecti'on toward the rotor axis as it approaches the discharge end of the casing;

OWEN J; GARTNER.

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