US3477178A

US3477178A - Cylinder treater apparatus

Info

Publication number: US3477178A
Application number: US498962A
Authority: US
Inventors: Clarence E Hulbert Jr
Original assignee: Capvac Ind Inc
Current assignee: Capvac Ind Inc
Priority date: 1965-10-20
Filing date: 1965-10-20
Publication date: 1969-11-11
Anticipated expiration: 1986-11-11

Description

C. E. HULBERT, JR

CYLINDER THEATER APPARATUS 4 Sheets-Sheet 1 Filed Oct. 20. 1965 CLARE/we E HuLazlezJe IN VEN TOR.

ATTORN'Y CYLINDER TR EATER APPARATUS Filed Oct. 20, 1965 4 Sheets-Sheet 2 CLARE/v05 E. HULBERZ' JR.

1 N V EN TOR.

ATTORNEY Nov. 11, 1969 c. E. HULBERT, JR 3,477,178

v CYLINDER TREATER APPARATUS Filed'Obt. 20. ,1965 4 Sheets-Sheet :3

76 5 /98 1 "FF/I96 v C LARENCE 6'. HULB-WII JR 1 252 INVEN'IOR.

ATTORNEY United States Patent 3,477,178 CYLINDER TREATER APPARATUS Clarence E. Hulbert, In, Houston, Tex., assignor to Capvac Industries, Inc., Freeport, Tex., a corporation of Texas Filed Oct. 20, 1965, Ser. No. 498,962 Int. Cl. B24c 3/32; B0811) 9/08 US. Cl. 51-8 6 Claims ABSTRACT OF THE DISCLOSURE This invention pertains generally to material treating apparatus and particularly to apparatus adapted for use in cleaning the interior of hollow elongated members such as railroad tank cars.

In my prior copending United States patent application, Ser. No. 463,781 filed June 14, 1965, entitled Abrasive Flow System and Methods, now abandoned, apparatus and methods were disclosed for cleaning storage tanks and other structures. However, such application did not disclose apparatus and methods for effective, safe, and economical cleaning and finishing the interior of elongated hollow members, such as railroad tank cars.

Railroad tank cars utilized in the storage and transportation of petrochemicals, pharmaceutical products, milk, brewery products, and other fluids have presented unique problems in the effective and efiicient cleaning thereof. For example, when chemicals are stored and transported by such railroad tank cars it is often necessary to burnout the interior of such tank cars by leaving such tank cars in a smoldering condition for a period of several days and possibly several weeks. This burning out method of cleaning the interior of railroad tank cars puts such cars out of service for several days and the resultant smoke and odor from the tank cars is offensive and sometimes dangerous. Also, when railroad tank cars which have carried gasoline or other flammable products are cleaned in a known manner, the hazards to men working inside of such railroad tank cars are great inasmuch as deadly fumes are present and working conditions are very hazardous and uncomfortable. Working conditions with known methods of hand operated cleaning nozzles, are very uncomfortable to workmen due to the extremely heavy dust contamination which poses many problems of inadequate visibility for the workmen to see and perform their work of surface preparation properly. Heavy saturated dust requires many safety devices such as life lines and air-fed helmets to minimize health hazards to the operators. Inadequate visibility increases the amount of time required for the area to be cleaned by many hours over the same size area where visibility is unlimited.

'Railroad tank cars must be cleaned of all mill scale and contamination prior to going into service to transport commodities. The cleaning requires abrasive cleaning methods because such tank cars must be lined with various chemical resistant coatings for the various commodities to be transported. All linings require the tank car to be abrasive cleaned prior to the installation of suitable lining. Thus, it is an object of the present invention to provide apparatus for treating the interior surface of a hollow, elongated member.

Another object of the present invention is to provide apparatus for removal of the residual debris which accumulates during abrasive cleaning of interior surfaces thereby removing hazardous duct conditions.

Another object of the present invention is to provide apparatus for safely, effectively, and economically cleaning the interior surfaces of hollow elongated members such as railroad tank cars.

Yet another object of the present invention is to provide apparatus for positioning inside a hollow elongated member to allow a uniform anchor pattern to be provided on the interior surfaces of such hollow elongated members thereby providing a uniform anchor pattern product by use of the process of the present invention.

A further object of the present invention is to provide apparatus for use in treating the interior surface of a hollow elongated member by selected rotation movement of a nozzle device and by selectively moving such nozzle device along the longitudinal axis of said hollow elongated member.

A still further object of the present invention is to provide apparatus for effectively and rapidly cleaning the interior surface of a hollow elongated member without having personnel in such elongated hollow member during such cleaning.

In the drawings FIGURE 1 is a cross-sectional, elevational view of the apparatus of the present invention positioned in a typical railroad tank car;

FIGURE 2 is a sectional, end view of the apparatus of the present invention taken along line 22 of FIG- URE 1;

FIGURE 3 is an end view partially in section of a nozzle and support of the present invention;

FIGURE 4 is an end view, partially in section of the support means and carriage means of the present invention;

FIGURE 5 is a side view of the support means and carriage means shown in FIGURE 4;

FIGURE 6 is a partial sectional, end view of the support means and the carriage means of the present invention; and

FIGURE 7 is a side view of the support means and carriage means of the present invention taken along line 7-7 of FIGURE 6.

Briefly stated, the present invention provides apparatus for treating the interior surface of an elongated hollow member. The apparatus of the present invention includes support means positioned generally along the longitudinal axis of such hollow member. Carriage means including drive means and ring means are positioned on the support means. Coupled to the carriage means are nozzle means including indexing means for rotational positioning of the ring means relative to the support means. Abrasive or other material is supplied to the nozzle means and selected rotational and axial movement of the nozzle means and carriage means is provided. As the nozzle means is rotationally indexed by the indexing means, material is discharged from the nozzles of the nozzle means in an arcuate pattern in which an arc of rotational movement of the nozzle means may be if three nozzles are used. After the rotational movement of the nozzle means occurs, the drive means of the carriage means may be actuated to move the carriage means and the nozzle means along the support means to a new axial position to allow the previous step of rotational movement of the nozzle means to be repeated. The procedure continues so that a method of treating the interior surface of the hollow elongated member is provided. If cleaning of the interior surface of the elongated hollow member is desired. a uniform anchor pattern may be provided on the interior surface so that such surface is, in effect, the product of a cleaning process. While the rotational movement of the nozzles means occurs, and the drive means is being actuated to move the nozzle means along the support means, a vacuum suction means may be employed along the bottom section of the hollow elongated member to pick up all contaminants and debris removed from the interitor surface so that there is no build up of debris in the bottom of the hollow, elongated member. Deep residual material collected would absorb the impact of the abrasive thus preventing proper cleaning of the lower section of the hollow, elongated member. Another suction means may be attached to the nozzle means with brush means so that the entire surface of the hollow elongated member may be properly cleaned.

Referring now to the drawings in detail, FIGURE 1 is a cross-sectional, elevational view of the apparatus of the present invention positioned in a typical railroad tank car. Tank car includes a hollow elongated member having an interior surface 12 with ends 14 and 16 closing the substantially cylindrical portion. Ends 14 and 16 may be suitably joined to cylindrical portions of the tank thereby providing a vessel capable of carrying bulk products such as food, petrochemicals, or any other material adapted to be transported by railroad tank car. A short stack 18 extends upwardly from the top portion of the railroad tank car 10 and allows material to be fed into the tank car or removed from the tank car. The top 20 of the stack 18 may be hinged or suitably coupled to stack 18 so that pressure may be maintained in tank car 10 if desired, and to provide proper sealing of the interior of the tank car 10.

Wheels

22, 24, 26, and 28 coupled to

axle assemblies

30 and 32 support the tank car 10 on track 34 and another track not shown in FIGURE 1. The tank car 10 shown in FIGURE 1 may be of any known type widely used throughout the railroad industry. Although the present invention is adapted for particular use with railroad tank cars, it will be appreciated in the later explanation and description of the invention that the apparatus and methods of the present invention may be utilized effectively with any vessel wherein abrasive cleaning or treatment of the interior surface of such vessel is required. Although in the following description and explanation of the invention abrasive cleaning such as sand blasting will be explained in detail, it will be appreciated that the present invention also may be utilized in painting, spraying, or other treating of the interior surface of any vessel.

Disposed substantially along the longitudinal axis of the tank car 10 is support means 40. Support means includes braces positioned as a three-way truss with sections of the support means being easily added or removed according to the requirements of a particular job. The ends of the guide rail assembly of the support means are provided with adjustable jack screws 42 and 44. Jack screw 42 may include member 46 positioned against the end of the truss and member 48 may be positioned against end 14 of the tank car 10. Handle 50 may be utilized for rigidly positioning the guide rail in place in a manner well known in the art. Jack screw 44 may include member 52 positioned against the truss and member 54 may be positioned against end 16 with handle 56 providing tightening of the jack screw to assure that support means 40 remains fixed rigidly inside the railroad tank car 10.

Positioned on the support means 40 is carriage means 60. Carriage means 60 includes drive means 62 and ring means 64. Nozzle means 66 includes indexing means 68 which provides rotational positioning of the ring means 64 as will be explained in detail subsequently. The nozzle means further includes a distributor head means 70 similar to the distributor head means identified in my previously mentioned copending application Ser. No. 463,781 filed June 14, 1965 entitled Abrasive Flow System and Methods. A vacuum suction means 72 includes member 74 coupled by suitable means such as welding at 76 to the carriage means 60.

Generally as may be ascertained from examination of FIGURE 1, material is sprayed or discharged in pattern 80 from a nozzle positioned on ring means 64 against the interior surface 12 of the tank car 10. In describing one operation of the apparatus of the present invention the ring means 64 and the nozzle means 66 are positioned at a selected location along support means 40 and rotational movement of the ring means 64 and nozzle means 66 occurs to clean the interior surface 12 of the tank car 10. As the entire circumference of the particular segment of interior surface 12 has been cleaned or otherwise treated with pattern 80, the carriage means 60 is moved longitudinally along support means 40 to another position and the pattern may again be applied against the interior 12 of tank car 10 to allow cleaning or treatment of another section of the tank car 10. It will be appreciated that as material such as abrasive used in cleaning the interior of tank car 10 is accumulated at the bottom or lower portion 82 of tank car 10, the vacuum suction means 72 will draw the accumulated material from the bottom of the tank car.

Control of the apparatus positioned in tank car 10 may be achieved outside of the tank car with control means operable by a single operator who may be simultaneously operating a plurality of similar devices in a plurality of tank cars. The control means 90 may be similar generally to the control means identified in my prior copending patent application and such control means may control the air supply through line 92 to the air motors utilized in the present invention as part of the drive means and part of the indexing means to be described in more detail subsequently. Abrasive or other material is provided through line 94 which is coupled to distributor head means 70 which in turn is coupled to

lines

96, 98, and and to the individual nozzle positioned on ring means 64 as will be explained. The control means 90 further may control the vacuum on line 102 coupled to the vacuum suction means 72. If abrasive material is used for cleaning the interior of the tank car, a vacuum is provided continuously to the vacuum suction means 72 to allow removal continuously of material collected at 82 in the lower portion of tank car 10. Briefly summarizing the supply lines for controlling the apparatus positioned in tank car 10, line 92 supplies pressurized fiuid such as compressed air to the drive means and indexing means, line 94 provides material such a abrasive material to the distributor head means 70, and line 102 provides a vacuum for withdrawing abrasive material which accumulates in the lower part of tank car 10 when abrasive cleaning is utilized.

Referring now to FIGURE 2, FIGURE 2 is a sectional, end view of the apparatus of the present invention taken along 22 of FIGURE 1. Tank car 10 is positioned on axle assembly 32 with an interior surface 12 to be cleaned or treated. Support means 40 includes

member

104, 106, and 108. The carriage mean 60 is positioned over a portion of the support means 40 with distributor head means 70 coupled by suitable means such as welding or bolting to the carriage means 60. Vacuum suction means 72 is positoned on support 74 to carriage means 60. Line 102, as explained previously, is coupled to vacuum suction means 72, and line 94 is coupled to the distributor head means 70. Lines 96 and line 98 are coupled to two of the nozzles 110, 112, and 114 with the other line 100 shown in FIGURE 1 not being shown in FIGURE 2.

It will be appreciated that nozzles 110, 112, and 114 are positioned at 120 angular degrees along the ring means 64 so that as the ring means rotate, the amount of rotatron does not have to be more than 120 angular degrees to allow the pattern 80 from nozzle and similar patterns from nozzles 112 and 144 to be greater than angular degrees to allow proper treating of the interior surface 12 of the tank car 10. It will be appreciated that although three nozzles are shown positioned at 120 angular degrees from each other on the ring means 64 that any number of nozzles may be utilized so long as the entire surface 12 is properly treated by the pattern from each nozzle positioned on the ring means 64. For example, if four nozzles are to be utilized, each nozzle would be placed 90 angular degrees from the other nozzle along the ring means 64 so that the rotational movement of ring means 64 would not need to be greater than 90 angular degrees to provide treating of the entire surface 12 of the tank car 10.

FIGURE 3 is an end view partially in section of a nozzle and support of the present invention. Ring means 64 has a bolt 116 having threads 118 positioned through opening 120 and coupled to holder 122. A screw 124 may be utilized for positioning nozzle 110 to holder 122. Nozzle 110 has an opening 130 through which abrasive material or other material may be discharged. Nozzle 110 may include

sections

132 and 134 wherein a nut 136 and wing 138 are coupled on one side and nut 140 and wing 142 are coupled on the other side to allow the nozzle 110 to be suitably coupled to a line or hose which is supplying abrasive or other material to the nozzle 110. It will be appreciated in viewing the nozzle of FIGURE 3 that the angular position of the three nozzles with respect to the ring means 64 may be varied so that the discharge from a particular nozzle against the interior surface 12 is at a suitable angle, as best seen in viewing FIGURE 1, so that a uniform anchor pattern will be provided on interior surface 12 as explained in my prior copending application. The interior surface 12 is provided with a uniform anchor pattern thereby causing the interior surface 12 to be a product formed by the process or method utilized in the present invention. The uniform anchor pattern is one of the principal objectives of the process or method utilized in the present invention. The angular positioning of the nozzle on ring means 64 allows a variation in the area covered by pattern 80 shown in FIGURE 1 and the corresponding patterns shown in FIGURE 2 so that interior surface 12 may be treated with abrasive material either in a concentrated pattern in the event that the corrosion or material to be removed from the interior surface 12 is heavy, or the pattern may be diffused so that a large area is treated in those instances where interior surface 12 does not require extensive treatment. Thus, it will be apparent that by positioning the nozzles utilized in practicing the present invention various patterns may be obtained which patterns are adapted for a particular job without the necessity of making substantial changes or modifications to the apparatus of the present invention so that such apparatus has wide adaptability while maintaining its effectiveness and efficiency under many varied operating conditions.

FIGURE 4 is an end view, partially in section of the support means and carriage means of the present invention. Support means 40 includes upper tubular memher 104 and

tubular members

108 and 106.

Members

104, 106, and 108 may be coupled together by a plurality of

braces

144, 146, and 148 to form a three-way truss as explained previously.

Thus, the

tubular members

104, 106, and 108 and the support members 144 146, and 148 and the jack screws not shown in FIGURE 4 provide support means for the carriage means 60. Carriage means 60 includes drive means 62 and ring means 64. Indexing means 68 may be positioned in the lower part of the carriage means so that member 150 engages the inside portion 152 of the ring means 64 to allow the nozzles coupled to the ring mean 64 to be suitably positioned. Indexing means 68 includes an air driven reversible motor. A friction drive or a geared pinion may be utilized. The indexing motor of indexing means 68 may be actuated by compressed air and is well known in the art. The motor, when reversed in rotation, causes member 150 to be reversed in rotation so that reverse movement of ring means 64 occurs. The motor of drive means 62 also is an air actuated reversible motor which may be reversed in rotation so that the drive shaft 154 may be rotated in either direction so that member 156 is rotated to cause the carriage means 60 to move in either direction along the support means.

Shaft 154 is coupled by a suitable connection 158 to the upper portion of carriage means 60 so that drive roller 156 of the drive means causes movement of the carriage means 60 along the support means 40.

Idler rollers

159 and 160 are positioned on

pins

162 and 164 respectively to allow the carriage means 60 to move positively along

tubular members

108 and 106 of the support means 40.

Ring means 64 is disposed from support means 40 by members such as

members

166 and 168 having for

example rollers

170 and 172 coupled thereto. The ring means 64 is held in position longitudinally by

members

174, 176, and 178 having

rollers

180, 182 and 184. As may be seen in FIGURE 5, similar support members and rollers are positioned on the back side of ring means 64 and such support members and rollers are not visible in FIGURE 4. The ring portion of the ring means may be segmented to allow easy positioning of the ring on the carriage means and on the support means.

In typical operation of the apparatus of the present invention, the carriage means 60 may be bolted in position or coupled in any other suitable manner along the support means 40.

The nozzle means on the ring means is rotated by the indexing means 68 until the limit switch stops 282 or 284 are engaged by

switch actuator arms

270 or 280.

Switch actuator arms

270 and 280 are coupled to limit

switches

278 and 272 respectively. The drive motor of drive means 62 is then actuated to cause longitudinal movement of the carriage means 60 along support means 40. Roller 222a is coupled through member 276 to count limit switch 274 which controls the distance the carriage means 60 will move by stopping drive means 62 in a manner well known in the art and for this reason not shown in the drawings and described in the specification.

After the carriage means 60 has moved to a new position along the support means 40, the ring means 64 is again rotated by the indexing means 68 but in the opposite direction from the previous rotation until another limit switch again is actuated at the end of the degree rotational movement. It will be appreciated by those skilled in the art that the particular combination of movements may be adjusted easily and quickly for various conditions and requirements so that rotational movement of the nozzle means may be accomplished simultaneously with the longitudinal movement of the carriage means along the support means.

FIGURE 5 is a side view of the support means and carriage means shown in FIGURE 4. Tubular member 104 may be seen to be coupled to tubular member 106 by braces such as

braces

186, 188, 190, and 192. Carriage means 60 is shown positioned on support means 40 with indexing means 68 shown in the lower portion of FIG- URE 5. Drive means 62 is shown in the upper part of FIGURE 5. Support 176 and idler roller 182 may be seen in the lower portion of FIGURE 5 and similar support 194 and idler roller 196 are shown on the other side of the ring of the ring means 64. Member 198 may be utilized as a brace for members 176 a nd 194 and to support the indexing motor. Support 178 and roller 184 are shown coupled to the carriage means 60 on one side of the ring of the ring means 64 While support 200 and roller 202 are positioned on the other side of the ring of the ring means 64.

Bolts

204, 206, 208, and 210 are utilized for positioning the upper part of carriage 60 to the lower part of the carriage means when the carriage means is positioned on the support means in the vessel or tank as explained previously. It will be appreciated in viewing FIGURE 5 that rotation of the ring means 64 to which the nozzles are coupled is achieved through rotation of the member coupled to the motor of the indexing means 68. The idler rollers such as

rollers

184, 202, 196, and 182 provide stability to the ring means 64 as rotation occurs.

FIGURE 6 is a partial sectional, end view of the support means and the carriage means of the present invention. The air motor of drive means 62 is coupled through suitable gear reduction means to drive shaft 154 which is coupled to roller 156. Support bearing 158 is provided for shaft 154 on carriage means 60. As explained previously,

tubular members

104, 106, and 108 of the support means 40 are coupled together by

brace members

144, 146, and 148.

Idler rollers

159 and 160 are positioned on carriage means 60 by suitable means such as

pins

162 and 164.

The carriage means may be constructed of suitable material such as sheet aluminum or other material which is light in weight yet sturdy and may include

plates

212, 214, and 216.

Plates

218 and 220 extend respectively from

plates

214 and 212.

Plates

218 and 220 provide a floating, support effect to idler rollers such as

rollers

159 and 160 so that movement of the carriage means along the support means may be achieved in a smoother manner and to allow enough friction for proper operation of the drive means 62. i

It will be understood and appreciated by those skilled in the art that although a drive means has been shown and described which utilizes a shaft and a friction drive wherein the weight of the carriage means provides friction on tubular member 104, other drive means may be provided so long as the carriage means is moved along the support means in a selected, controlled manner. If the apparatus of the present invention is used in treating the inside of pipe, for example, the apparatus may remain fixed while the pipe is moved. The apparatus of the present invention may be used effectively in many ways so long as there is relative movement between the vessel or workpiece and the apparatus.

FIGURE 7 is a side view of the support means a carriage means of the present invention taken along line 77 of FIGURE 6. The drive means 62 is shown coupled to roller 156 positioned on tubular member 104 of the support means 40. Roller 222 is positioned on tubular member 104 and supported in a manner similar to the support provided for roller 156. Idler roller 160 is coupled to tubular member 106. Idler roller 224 is shown positioned in rolling contact with member 106. Lower plate 216 is coupled to shaft or pin 164 and to pin 226. As explained previously, drive means 62 provides friction drive through roller 156 on tubular member 104 to cause the carriage means 60 to move longitudinally along the support means 40.

Thus, the present invention provides apparatus for treating the interior of an elongated member having an opening therein so that the interior surface of such member is provided with an anchor pattern which is uniform whenever the interior surface of such member is cleaned with an abrasive such as sand. The apparatus and methods of the present invention also may be utilized for painting or for applying other fluid material to the interior surface of tubular members including tanks or vessels. The present invention overcomes many of the obstacles and problems which have been encountered in the cleaning and treatment of interior surfaces by eliminating the need for workmen to be inside the tank or vessel during cleaning or treatment thereby minimizing the danger to workmen. The present invention also allows effective treatment to be made more rapidly than in the past thereby putting expensive equipment such as railroad tank cars back into service sooner.

Although a preferred embodiment of the invention has been shown and described, it will be apparent to those skilled in the art that many modifications and improvements may be made to the apparatus and in performing the methods of the present invention without departing from the spirit of the invention as defined by the following claims. Although such claims may be presented in indented format to facilitate reading and understanding thereof, such indented format is not to be construed as a structural or functional limitation of the elements recited in such claims.

I claim:

1. Apparatus for treating the interior surface of a hollow, elongated member having first and second ends, said apparatus including in combination:

support means disposed in said member and coupled to each of said first and second ends,

carriage means coupled to said support means, and

nozzle means coupled to said carriage means, said carriage means being adapted for movement on said support means with said nozzle means being adapted for independent movement of less than 360 degrees rotation relative to said support means.

2. Apparatus for cleaning at least a portion of the interior surface of a hollow, elongated member having first and second ends, said apparatus including in combination:

support means disposed in said member along its longitudinal axis and coupled to each of said first and second ends,

carriage means coupled to said support means, and

nozzle means coupled to said carriage means, said carriage means being adapted for longitudinal movement on said support means with said nozzle means being adapted for independent rotational movement of less than 360 degrees on said support means.

3. Apparatus for cleaning at least a portion of the interior surface of a hollow, elongated member having first and second ends, said apparatus including in combination:

support means disposed between said first and second ends of said member,

carriage means coupled to said support means, said carriage means including drive means for moving said carriage means relative to said support means, and

nozzle means coupled to said carriage means, said nozzle means being adapted for independent move ment of less than 360 degrees rotation relative to said carriage means.

4. Apparatus for treating the interior surface of a hollow, elongated member having first and second ends, said apparatus including in combination:

support means disposed in said member between said first and second ends, carriage means coupled to said support means, nozzle means coupled to said carriage means, said carriage means being adapted for movement on said support means with said nozzle means being adapted for independent rotational movement of less than 360 degrees on said support means, and

a source of fluid coupled to said nozzle means for discharge against said interior surface of said hollow, elongated member.

5. Apparatus adapted for use in treating the inside surface of a hollow, elongated member, said apparatus including in combination:

carriage means including an elongated housing having a plurality of sides, a plurality of rollers coupled to said plurality of sides, a plurality of support members extending radially from said housing, and first and second power means, said first power means being coupled to at least one of said plurality of rollers, and

nozzle means including a ring member disposed around said housing and supported by said support members, said ring member being coupled to said second power means to provide rotational movement of less than 360 degrees to said ring member.

6. Apparatus adapted for use in treating the inside surface of a substantially hollow, elongated member, said apparatus including in combination:

carriage means including an elongated housing having a plurality of sides, drive means coupled to said 9 housing, a plurality of support members extending radially from said housing, and first and second power means, said first power means being coupled to said drive means, and nozzle means including a ring member disposed around said housing and supported by said support members, said ring member being coupled to said second power means to provide selective rotational movement of less than 360 degrees to said ring member.

References Cited UNITED STATES PATENTS 3,362,109 1/1968 Wallace 519 847,269 3/1907 Wise 5112 2,358,557 9/1944 Boyd et a1. 518 2,455,514 12/1948 Mead 518 2,884,745 5/1959 Fritze et a1. 5111 3,058,137 10/1962 Doyle et a1. 518 X 3,109,262 11/1963 Weaver et a1. 5111 X FOREIGN PATENTS 250,097 6/1963 Australia.

US. Cl. X.R.