US2204618A - Direct impulse sandblast system - Google Patents

Description

June 18, 1940. L. D. PEIK DIRECT IMPULSE SANDBLAST SYSTEM Original Filed Oct. 12, 1932 2 Sheets-Sheet 1 INVENTOR Mm'sfl Pa /Z BY 4 ATTORNEYS June 18, PE K 2,204,618

DIRECT IMPULSE SANDBLAST SYSTEM Original Filed Oct. 12,1932 2 Sheets-Sheet 2 INVENTOR' 01113 .2 Pezlaf 4 ATTORNEYS Patented June 18, 1940 UNITED STATES DIRECT IMPULSE SANDBLAST SYSTEM Louis D. Peik, Mishawaka, Ind., assignor to The American Foundry Equipment Company, New York, N. Y., a corporation of Delaware Application October 12 1932, Serial No. 637,389 Renewed August 12, 1939 11, Claims.

The invention relates to abrasive blast equip-- ment, and more particularly to a machine for directly imparting a blasting velocity to the abrasive particles.

According to the invention a stream of moving abrasive particles for cleaning castings and the like is obtained by applying directly a mechanical force to the particles as contrasted to the usual methods using high ,pressure air.

According to the invention, abrasive particles, such as sand or shot, with substantially no air are fed into one or both sides of the center of a centrifugal throwing machine or wheel having a series of outwardly extending nozzles. The nozzles may extend substantially radially and a little forward in the direction of rotation of the wheel. The walls of the nozzles, which wear away due to the abrasive action, may have removable wearing plates of special material. If desired,- a guard may be placed around a portion of the periphery of the wheel so that the abrasive particles will be directed to one side of the wheel only. By rotating the wheel at a proper speed and adjusting the rate of feed of the abrasive to the center of the Wheel, the abrasive particles are accelerated and thrown tangentially from the wheel with great force.

The invention also consists in certain new and original features of construction and combinations of parts hereinafter set forth and claimed.

Although the novel features which are believed to be characteristic of this invention will be particularly pointed out in the claims appended hereto. the invention itself, as to its objects and advantages, and the manner in which it may be carried out, may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part thereof, in which:

Fig. l is a section through the machine, with parts broken away, to show the construction thereof;

Fig. 2 is a section on the line 2-2 of Fig. 1;

Fig. 3 is a section illustrating a modified form of throwing wheel;

Fig. 4 is a transverse section through Fig. 3;

Fig. 5 illustrates a modified form of machine; and

Fig. 6 is a partial section taken through Fig. 5.

In the following description and in the claims, various details will be identified by specific names for convenience, but they. are intended to be as generic in their application as the art will permit. I

Like reference characters denote like parts in the several figures of the drawings.

In the drawings accompanying and. forming part of this specification, certain specific disclosure of the invention is made for purposes of explanation, but it will be understood that the details may be modified in various respects without departure from the broad aspect of the in. vention.

Referring now to the drawings, and more par- 10 ticularly to Figs. 1 and 2. the machine comprises a stationary hearing In in which is journalled a rotary support II having a drive pulley l2. The support ll drives the wheel I3. If desired, a trough shaped guard M may be disposed around 15 a portion of the periphery of the wheel 13 to limit the area from which the abrasive is ejected. A bracket 28 conveniently supports the guard M.

For supplying the wheel l3 with abrasive, a feed conduit l5 having a close fit with the side 2 of the wheel may be provided. Particles of sand or other abrasive with substantially no air may be fed into this conduit.

The wheel l3 comprises a side Wall plate It to which are secured peripheral walls ll, and 25 nozzle walls I9 and 20 forming the nozzles IS. The back walls or throwing blades 20 of the nozzles l3 may be provided with removable wearing plates or liners 2i secured thereto, made of hard, long wearing material, such as tungsten 3 carbide.

A side wall plate 22 is secured to the rest oi. the wheel by a series of bolts 23, these bolts also securing the wheel to the support M. It will be noted that the inner ends of the nozzles l8 inter- 35 .sect a circular space or center inlet 27 which communicates with the feed conduit l5 through an opening in the plate 22. For removably securing the wearing plate or liners 2| in position, they may be provided with projections 24 40 which fit in corresponding holes in the side wall plates I6 and 22. It will be understood that these liners 2! may be removed from time to time as they are worn out and replaced with new ones.

The front walls IQ of the nozzles l8 and the peripheral walls I! project radially to form shields 26 which assist in protecting the discharge ends of the nozzles l8 from the efiects of eddy currents and windage set up by the rapid rotation of the wheel. It will be noted that the front walls 59 are provided with holes 25 and that the liners 2i are substantially tangential to the circular space 2i. Also, it will be noted that the nozzles l8 extend forwardslightlydmthe dl- I simultaneously from both sides.

rection of rotation of the wheel, as indicated by the arrow, and that the nozzles converge toward the outer end thereof, thereby assisting in the eflicient discharge of the abrasive.

In operation, the wheel I3 is rotated at proper speed by means of a belt applied to thepulley l2 and sand or other abrasive is fed with substantially no air into the feed conduit IS. The rapid rotation of the wheel I3 accelerates the abrasive particles and discharges them through, the discharge ends of the nozzles tangentially of the periphery of the wheel at high speed.

As an example, in one construction successfully used, the impulse wheel l3 was 14 inches in diameter, about 1 /2 inches wide and was driven at 3000 revolutions per minute by a 10 H. P. motor. about 300 lbs. of steel abrasive in twenty seconds.

It will be understood that the work to be cleaned will be placed in the path of the abrasive stream thrown from the wheel, and that, in' case the guard is used, the work will be placed on one side of the wheel only. In case the guard H is omitted, the streams of abrasive will be directed in all directions and the work .to be cleaned may be placed on all sides of the wheel. It will be understood that the speed of the wheel may be varied, its diameter may be varied and the amount of abrasive fed thereto may be varied, to give best results.

Referring now to Figs.,8 and 4, in this construction the wheel 29 is fed from both sides and the guard is omitted. It will be noted that the guard may be used with this form and that, if desired, Fig. 1 may be fed from both sides also.

The construction of the wheel 29 is similar to that of the wheel l3, except that the nozzles 32 do not have any forward walls. The wheel is made up of two plates 30 and 3| clamped together by bolts 39 in a manner similar to Figs. 1 and 2. The rear walls of the nozzlesare denoted by 50 and the peripheral walls of the; wheel are denoted by 5|, these walls being secured to the plate 3|.

. The removable liners 33 may be positioned in a manner similar to the liners 2|. The nozzles 32 are provided with shields 52 for the purpose of protecting the discharge ends of the nozzles from eddy currents, as described above.

For supporting the wheel, a bearing 34 is provided in whichis a hollow shaft 36 having mounted thereon a drive pulley 35. The shaft 35 supports a plate 53 through which the bolts 39 project, which clamp the parts of the wheel together.

For feeding abrasive to the wheel, stationary feed pipes 31 and 38 are provided on opposite sides. The pipe 31 has a close fit with the plate 30 which has an opening therein leading to the inner ends of the nozzles 32. The feed conduit 38 has a close fit with the hollow shaft 36 which communicates with the interior of the wheel, as shown.

In this form, the operation is similar to that described above, except that the abrasive is fed Furthermore, the absence of forward walls on the nozzles 32 causes a different action on the ab'ram've accelerated through these nozzles.

Referring now to Figs. 5 and 6, the wheel in this figure is similar to Fig. 1, but may also be constructed like the wheel in Fig. 3. The wheel '40 is fed by a feed pipe 4| in a single direction only, which is shown as downwardly in the figure. It will be noted particularly in Fig. 6 that the feed pipe 4| is provided with a contracted discharge opening which directs the abrasive sub- The wheel consumed and discharged particles at a blasting velocity including, spaced ing contact'with the side wall plates l6 and 22 of the machine. The abrasive fed into the wheel 5 in a single direction will be discharged from the wheel in a single direction at an angle from the direction of feed pipe 41 depending upon the speed of rotation of the wheel and constants of the wheel itself. The abrasive moves into the wheel through the feed pipe 4|, as shown by the arrow in Fig. 6, either by compulsion of gravity or by a movement of air as illustrated in Fig. 4, orboth. It will be understod that the wheels, shown in Figs. 1, 2, 5 and 6, may each be used either horizontally or vertically.

The advantages of the present invention are the elimination of the expensive air pressure apparatus used in'conventional systems. This apparatus normally'comprises an air compressor, 20 a pressure tank and mixing valves. According to the present invention the velocity is imparted to the abrasive particles by direct impulse from the impulse wheel. -A high velocity is obtained without the use of air in a much simpler manner and at considerably less expense than with systems using air pressure.

While certain novel features of the invention have been disclosed and are pointed out in the annexed claims, it will be understood that vari- 30 ous omissions, substitutions and changes may be made by those skilled in the art without departing from the spirit of the invention.

What is claimed is: v

1. A rotor for throwing abrasiveparticlesincluding a rotatably'mounted side wall member, a plurality of blades supported from said side wall member and extending inwardly short of the axis of rotation of said side wall member to define a central opening, and an abrasive supply conduit having a turned formation on the end thereof which extends into said central opening, said tumed formation having a discharge outlet so positioned and arranged as to direct the abrasive radially across the inner ends of said blades.

2. In a-wheel for directly impelling abrasive particles, a plurality of outwardly extending v throwing blades extending from an inlet at the center of the wheel outwardly to the. wheel periphery, and shields positioned in advance of said 50 blades to protect the abrasive discharge from windage.

3. A rotor for throwing abrasive particles including a plurality of spaced, rotatably mounted blades extending inwardly short of the axis of rotation thereof to-define a central opening, an abrasive supply conduit'having a turned end portion which extends into said opening. said end portion having a contracted discharge outlet so arranged that the abrasive dischargedfrom'said. outlet is directed radially across the inner ends of said blades and within the path of movement thereof. I

4. A machine for directly impelling abrasive 65 rotatably mounted plates extending substantially parallel to one another, radially arranged throwing blades positioned between and connecting said plates, and a feed conduit having an angular portion shaped to direct a contracted stream of abrasive substantially radially across the inner ends of said blades as they respectively arrive at a predetermined position during rotation.

5. A machine for directly impelling abrasive particles at a blasting velocity including, a pair 75 of spaced rotatably mounted plates extending substantially parallel to one another, means for rotating said plates, removable and replaceable throwing blades positioned between and connecting said plates, said blades extending inwardly short of the axis of rotation to define a central opening, and a supply conduit having a turned formation on the end thereof extending into said central opening, said turned formation terminating in a discharge outlet operative to direct a contracted stream of the abrasive in a radial direction across the inner ends of said blades as they respectively arrive at a predetermined point during rotation.

6. A wheel for impelling abrasive particles at blasting velocities including, removable and replaceable throwing members extending from an inlet at the center of the wheel outwardly, means for supporting said members, means for detachablysecuring said members in operative position, and means including a feed conduit having an angular portion positioned within said inlet for directing a contracted stream of abrasive substantially radially across the inner ends of said members and into the path of movement thereof.

'7. In a rotor for throwing abrasive at blasting velocities including a side wall member, a plurality of spaced throwing blades supported by said side wall member and extending inwardly short of the axis of rotation of said side wall member to define a central opening, an abrasive supply conduit having the end thereof terminating in an elbow formation which extends into said opening, said elbow formation terminating in an abrasive discharge outlet extending substantially axially of the rotor and operative to direct the abrasive radially into the path of rotation of said blades. 8. A wheel for Qrectly impelling particles at blasting velocities; including a rotatably mounted disc, a plurality of radial throwing elements supvelocities comprising, a center inlet, throwing blades extending outwardly from said inlet, and a nozzle of elbow formation, said nozzle of elbow formation having a discharge opening arranged to direct abrasive substantially radially across the inner ends of said blades, the discharge opening in said elbow formation being substantially parallel to the inner ends of said blades and of less extent than the width of said blades.

10. A machine for directly impelling abrasive particles at blasting velocity including, a rotatably mounted side wall" member, a plurality of abrasive impelling members provided thereon, said members terminating short of the rotating axis of said side wall members to define an abrasive admitting space, a tubular feed conduit having an angular formation at the end thereof extending into said central space, said angular formation having an opening therein which extends in a direction axially of the machine and substantially parallel to the inner end of said -material into said chamber, said means including a supply conduit having an angular formation at theend thereof projecting within the confines of said side walls, said angular formation having a discharge opening positioned entirely on one side of the axis of rotation of the wheel and delivering a contracted stream of the abrasive over the inner edges of said blades, said discharge opening extending axially of the throwing wheel in a direction substantially parallel to the inner edges of said blades and having an axial extent somewhat less than the width of the inner edges of said blades so as to substantially confine the abrasive to the area of said blades. and out of wearing contact with said side walls.

LOUIS D. PER.

Images