US3566598A - Automatic ring-rail downing system - Google Patents

Abstract

THE INSTANT INVENTION UTILIZES A PNEUMATIC MECHANISM HAVING AN AIR CYLINDER CONNECTED WITH A LEVER FIXEDLY ATTACHED TO THE CROSS-SHAFT OF A CONVENTIONAL SPINNING FRAME. ALTERNATIVELY, THE AIR CYLINDER MAY BE CONNECTED WITH THE TRAVERSE ROD BY A CHAIN. A PLURALITY OF PNEUMATIC SWITCHES AND VALVES ARE LOCATED TO PERMIT CONTROL, BY THE RECIPROCATING RING-RAIL, OF A PNEUMATIC SYSTEM CONTAINED IN A CONTROL ROD POSITIONED NEAR THE SPINNING FRAME.

Description

March 2 1971 v P. c. GODFREY 3,566,598

AUTOMATIC RING-RAIL DOWNING SYSTEM Filed Oct. 30, 1968 4 Sheets-Sheet 1 PAUL C. GODFREY 1N VENTOR.

ATTORNEY March 2, 1971 P. C. GODFRE Y AUTOMATIC RING-RAIL DOWNING SYSTEM Filed Oct. 30, 1968 4 Sheets-Sheet 2 U! 58 s 94 112 n2 /5 I I l J PAUL C. GODFREY INVENTOR.

ATTORNEY March 1971 P. c. GODFREY AUTOMATIC RING-RAIL DOWNING SYSTEM 4 Sheets-Sheet 5 Filed Oct. 30, 1968 FIG.

PAUL C. GODFREY INVENTOR.

ATTORNEY March- 1971 P. c. GODFREY AUTOMATIC RING-RAIL DOWNING SYSTEM Filed Oct. 30,

4 Sheets-Sheet L 206? ee Ll PAUL C. GODFREY ATTORNEY United States Patent 3,566,598 AUTOMATIC RING-RAIL DOWNING SYSTEM Paul C. Godfrey, Enoree, S.C., assignor t0 Byars Machine Company, Laurens, S.C. Filed Oct. 30, 1968, Ser. No. 771,870 Int. Cl. D0lh 9/14; B6511 51/16, 54/28 US. Cl. 57-54 8 Claims ABSTRACT OF THE DISCLOSURE The instant invention utilizes a pneumatic mechanism having an air cylinder connected with a lever fixedly attached to the cross-shaft of a conventional spinning frame. Alternatively, the air cylinder may be connected with the traverse rod by a chain. A plurality of pneumatic switches and valves are located to permit control, by the reciprocating ring-rail, of a pneumatic system contained in a control box positioned near the spinning frame.

This invention relates generally to textile spinning frames and more particularly to an automatic downing mechanism for the ring-rail of such frames.

As is well known, spinning frames utilize a reciprocating ring-rail which gradually is raised by a counterweight to eifect building of yarn on the bobbin. Because of the extreme weight of the ring-rail and its attendant structure and the counterweight which assists in gradually causing the ring-rail to raise as it fills yarn on the bobbins, there is a tremendous weight that must be lowered in order to position the ring-rail for doffing of the bobbins. It has been known in the past to utilize various mechanisms to assist the operator of the spinning frame in lowering the ring-rail. The conventional method of lowering the ring-rail is for the operator to utilize his leg in forcing the ring-rail and counterweight downward. This method is completely unsatisfactory and is substantially impossible for a Woman operator.

Various devices have been utilized to assist in lowering or downing the ring-rail, such as cables connected with the counterweight system that are operated by a motor connected to an electrical switching system operated by the ring-rail when it reaches its upper position. It has also been proposed to utilize complicated gearing systems for reversing the building procedure and forcing the ring-rail back to the doffing position. It also has been proposed to utilize pneumatic systems for lowering the ring-rail, but such systems have been complicated and require extensive maintenance and generally have been unacceptable to the industry. Each of the discussed mechanisms requires complicated systems that are diflicult of installation. Generally, these previously proposed mechanisms not only require complicated structures but require a high degree of knowledge and maintenance to keep them in operational condition.

In order to overcome the disadvantages of the prior art, the instant invention contemplates utilizing a pneumatic system having an air cylinder connected with a lever fixedly attached to the cross-shaft of a conventional spinning frame. Alternatively, the air cylinder may be connected with the traverse rod by a chain. A plurality of pneumatic switches and valves are located to permit activation, by the reciprocating ring-rail, of a pneumatic system contained in a control box positioned near the spinning frame.

It is an object of the instant invention to provide a system for automatically downing the ring-rail of a textile spinning frame.

Another object of this invention is to provide a versatile automatic downing system having controls permitting any desired and uniform wrap-up on the bobbin.

A further object of the instant invention is to provide Patented Mar. 2, 1971 a ring-tail downing system that substantially reduces waste and increases production in the spooling and winding phases of textile production.

Still another object of this invention is to provide an automatic ring-rail downing system that utilizes pneumatic pressure activated by the ring-rail.

A still further object of the instant invention is to provide a pneumatic circuit activated by the ring-rail of a spinning frame to operate an air cylinder connected with the ring-rail and having automatic controls for timing the downing of the ring-rail.

Yet another object of this invention is to provide an air cylinder connected with a control panel utilizing a plurality of pneumatic switches and valves activated by the ring-rail for automatic downing thereof.

A more complete appreciation of the invention and many of the attendant advantages thereof will be readily understood by reference to the following description when taken in conjunction with the accompanying drawings wherein:

FIG. 1 is a side elevational view showing the general location of the instant invention in relationship to the conventional spinning frame;

FIG. 2 is an end view, with portions omitted for clarity, of the system of FIG. 1;

FIG. 3 is an enlarged side view of a portion of the invention shown in FIG. 1;

FIG. 4 is an end view of the portion of the mechanism shown in FIG. 3;

FIG. 5 is a diagrammatic view of the control system for the instant invention;

FIG. 6 is a side elevational view showing the general location of an alternative embodiment of the instant in vention in relationship to the conventional spinning frame;

FIG. 7 is a top view of a portion of the invention shown in FIG. 6 as related to the conventional spinning frame;

FIG. 8 is a diagrammatic view of the control system for the alternative embodiment of the instant invention;

FIG. 9 is a diagrammatic view of the control system for the instant invention.

Referring now to the drawings and more particularly to FIG. 1 wherein the instant inventive control mechanism 10 is shown installed on a conventional spinning frame 12. Spinning frame 12 includes a reciprocating ring-rail 14 with bobbins 16 located on spindle rail 20. Lifting rods 18 are utilized for movement of ring-rail 14 by the conventional operating mechanism of spinning frame 12 which is not shown due to its conventionality. counterweight 22 is conventional and rigidly mounted on cross-shaft 24 which is connected with the operating mechanism of spinning frame 12.

Lever 26 is fixedly attached to cross-shaft 24 on spinning frame 12 and extends downwardly therefrom towards the floor upon which the spinning frame is mounted. A pair of plates 28 are located on each side of lever 26, as is best seen in FIGS. 3 and 4. Plates 28 are attached to lever 26 by a plurality of bolts 30 and extend beyond the end of lever 26 to provide an opening for a purpose to be more fully understood hereinafter. Plates 28 are provided with an aperture 32 for receiving arms 36 extending from swivel 34. This arrangement permits swivel 34 to rotate within the area between plates 28 and the end of lever 26. Swivel 34 has center bore 38 for receiving linkage rod 40. Linkage rod 40 has threads 42 on the end thereof for receiving nuts 44, which prevent rods 40 and spacers 46, located between nuts 44 and swivel 34, from becoming disassembled. The opposite end of linkage rod 40 from threads 42 has enlargement 48 with a central end bore 50 which is threaded for receiving piston rod 52.

Piston rod 52 has piston 54 on the end thereof and extends into cylinder 56 in a manner such that air entering 3 cylinder 56 through air line or conduit 58 will cause movement of piston 54 and the attached piston rod 52 and linkage rod 40.

Referring now to FIG. wherein control panel 60 is shown in diagrammatic form, pneumatic supply source 62 is connected by conduit 64 with an air filter 66 and an air lubricator 68 and regulator 72. Rail switch 70 is also connected by conduit 64 to the source of air 62. Line or conduit 74 leads from regulator 72 to manual lowering switch 76. Line 78 feeds from line 74 and leads to onventional air gauge 80. Line 82 also leads from line 74 to manual reset valve 84. Air line or conduit 86 leads from conduit 74 to a conventional four-way valve 88 which in turn is connected b conduit 90 with rail switch 70 and to manual release valve 84 by air line 94. Line 98 leads from manual switch 76 to shuttle valve 100 which is connected with four-way valve 88 by line 102. Shuttle valve 100 is connected with a conventional flow control 106 by conduit 104. Flow control 106 is utilized to reduce the flow of air to cylinder 56 or to reduce or increase the speed of the flow of air and is connected with quick exhaust valve 110 by conduit or air line 108. Quick exhaust valve 110 is connected with cylinder 56 by conduit 58 as hereinabove noted. It is to be understood that air chambers 112 may be inserted in lines 94 and 90 to provide smoother operation of four-way valve 88.

Referring now to FIG. 6 wherein an alternative embodiment of the instant invention is shown as applied to a conventional spinning frame 12 having ring-rail 14 with bobbins 16. Ring rail 14 is operated by lifting rods 18 and bobbins 16 are located on spindle rail 20.

The alternative embodiment of the instant invention shown in FIG. 6 includes piston rod 152 attached to piston 154 and mounted in a conventional air cylinder 156. Cylinder 156 is mounted on Sampson 160 in the conventional framework of spinning frame 12.

Chain 158 connects piston rod 152 with traverse rod 162 which is connected by lever 164 to cross-shaft 24. The traverse rod arrangement is conventional in existing spinning frames and chain 158 functions to relieve any wear and maintenance through the movement of piston rod 152 or traverse rod 162 which reciprocates in raising and lowering ring-rail 14 during the building of bobbins 16. Arc element 166 is mounted on cross-shaft 24 and has chain 168 attached thereto and extending to builder mechanism 170. Builder mechanism 170 is conventional and includes pulley 172 for guiding chain 168 to wrap-up gear or sprocket 174. Wrap-up gear 174 is operated by worm gear 176, which is mounted on a common shaft with pick gear 178, see FIG. 7. Pick gear 178 is mounted on shaft 180 that extends inwardly under spinning frame 12 for mounting of air motor 182 thereon for a purpose to be more fully described hereinafter. Mounting brackets 184 mounts pawl 186 which causes pick gear 178 to rotate in one direction but operates as a lock to prevent gear 178 from rotating in the opposite direction. Cam 188 is of conventional construction and is as used on conventional spinning frame 12 to operate the builder mechanism by its connection to the typical electrical motor, not shown, utilized in this type of operation. Adjustable stop 190 operates pawl 186 when cam 188 forces the builder mechanism downwardly such that pawl 186 turns pick gear 178 causing worm gear 176 to rotate wrap-up sprocket 174 to lengthen chain 168 and cause traverse rod 162 to gradually be raised for a similar gradual raising of rinrail 14.

FIG. 8 shows a diagrammatic view of control panel 200 which is utilized in automatically operating the downing mechanism shown in FIG. 6. Air filter 202 and pressure regulator 204 are inserted in supply line 206 which goes through filter 202 and extends to rail activated switch 226. The return line 224 connects rail switch 226 to one side of four-way valve 220.

Supply line 208 connects with supply line 206 and goes through pressure regulator 204 to a conventional pressure 4 gauge 210. Pressure lines 212, 214 and 216 leave gauge 210 in diverse directions aswill be seen by reference to FIG. 8. Supply line 212 extends from gauge 210 to manual 210 to manual reset valve 218. Line 214 extends to manual control valve 228 and line 216 extends from gauge 210 to four-way valve 220.

Pressure line 222 leads from manual reset valve 218 to four-way valve 220. Thus it is seen that air pressure from a source, not shown, flows through line 206 and is held by rail switch 226 until switch 226 is activated by ring-rail 14 to permit pressure to flow into return line 224 and into four-way valve 220. This action permits four-way valve 220 to be opened permitting pressure in lines 208 and 216 to flow into line 238 which supplys regulator 240 and pressure line 276. Pressure line 276 leads to cylinder 156 for a purpose to be more fully understood hereinafter.

Air pressure in line 208 flows through gauge 210 into line 214 and into manual control valve 228. When an operator activates valve 228 the air pressure thereagainst flows into line 230 and into shuttle valve 232. From shuttle valve 232 the air pressure flows through line 234 into T 268 from which it flows into line 264 that connects T 268 with two-way valve 262. The pressure then flows from valve 262 into line 266 that connects with line 272 to flow through lubricator 274 into cylinder 156 for operation thereof. Thus it is seen that manual opera tion of switch 228 permits downing of ring rail 14 at any time desired by the operator of spinning frame 12.

When the pressure from line 216 is flowing through valve 220 it flows through line 238 and regulator 240 which connects with cylinder 156 by line 276 to maintain piston 154 in an essentially closed position permitting the conventional operation of spinning frame 12. Upon activation by cam 198 rail switch 226 permits pressure to flow into four-way valve 220 to adjust the supply flowing therethrough to enter line 238 and line 236. Supply line 242 connects with line 236 and permits a supply of air pressure to reach valve switch 244 that is opened by cam 198. Once valve 244 is opened the supply of air pressure flows through line 246 to delay circuit 250.

Delay circuit 250 extends from valve switch 244 to lubricator 274 to provide operation time for the additional winds required by a warp type spinning frame. Line 252 permits the air to flow to timer 254 and volume control 256. Timer 254 and volume control 256 are connected by line 258 with pilot actuator 260 that functions to permit a gradual rise in pressure and not a sudden burst of pressure to be placed on two-way valve 262. Operation of valve 262 permits the supply of air pressure flowing therein to pass into lines 266 and 272 which operates piston 154 and its attendant piston rod 152 to draw chain 158 to the left, as seen in FIG. 6, and thereby down ring-rail 14. Pressure line 246 also leads to pilot actuator 260 connected with two-way valve 270 to permit the pressure coming from valve switch 244 to enter and close valve 270' forcing a pressure buildup in delay circuit 250. After the buildup of pressure in valve 262, valve 262 opens to admit pressure into line 266 and 272. In this regard it is to be noted that valve 262 may include and adjustable feature for alteration of the delay effected by circuit 250 as desired.

Supply line 282 leads from supply line 206 to cam operated switch 280 which is utilized for stopping the electrical motor operating spinning frame 12. Air pressure is maintained on cam operated switch 280 until that switch is opened by cam 198 to permit the pressure to flow through line 284 to pilot actuator 288 which operates the electric motor control switch 286. It is to be noted that pilot actuators 288 may be inserted in lines 222 and 224, if desired, for the normal results to be obtained therefrom.

Referring now to FIG. 9 wherein supply line is shown to extend from control panel 200 to unwind switch 292 that is connected with air motor 182 by line 294.

Line 290 also connects with wind switch 296 that is connected with air motor 182 by line 298. Both unwind switch 292 and wind switch 296 are manually operated. Line 298 connects with line 302 which extends from air motor 182 to check valve 308 inserted in supply line 272, which provides a supply of air to cylinder 156 for operation thereof to down ring-rail 14, in order that air pressure in line 272 passes through check valve 308 into motor 182 and pawl cylinder 306. Line 304 extends from line 302 to pawl cylinder 306 to permit the above described action to cause pawl 186 and motor 182 to operate continually to wind and shorten chain 168 until manual reset valve 218 is activated to remove pressure from line 272. Activation of valve 218 shifts four-way valve 220 to admit air into line 238, to regulator 240 and line 276 to force piston 154 to an inoperative position at the rear of cylinder 156. Thus relieving pressure in line 272. Normally this action takes place after the full bobbins have been removed and replaced with empty bobbins. This construction thus permits complete automatic operation of a conevntional spinning frame 12 by the installation of the instant invention which requires a minimum effort and upon installation is easily maintained to permit conventional spinning frame 12 to operate completely automatically.

OPERATION Source 62 provides a supply of filtered and lubricated air under, as an example, 80 pounds per square inch pressure to regulator 72 and rail switch 70. As ring-rail 14 is gradually moved upward by lifting rods 18 and the conventional mechanism for operating spinning frame 12, ring-rail 14 is caused to contact switch 70. The supply of air passes through regulator 72 and flows through conduit 74 to manual switch 76 which precludes further flow of air pressure in line 98 and permits gauge 80 to read the pressure in air line 74. This supply of air passes through conduit 82 to release valve 84 where it again is prevented from further passage through the lines.

The supply of air from regulator 72 flows through conduit 86 to four-way valve 88 where it is prevented from flowing further. When ring-rail 14 closes switch 7 0 the air pressure is permitted to flow through valve switch 70 into conduit 90 and through pilot actuator 112 and into four-way valve 88. This causes movement of the spool of valve 88 and permits the pressure flowing into valve 88 from conduit 86 to pass through valve 88 into conduit 102 and to shuttle valve 100. The air entering shuttle valve 100 opens that valve and permits the air to flow into conduit 104 and flow control 106 from which it continues through conduit 108 into quick exhaust valve 110 and through conduit 58 into cylinder 56 where it activates and moves piston 54 and the attendant piston rod 52.

As seen in FIG. 3, movement of piston 52 causes linkage rod 40 to move to the left and forces spacers 46 against lever 26 and thereby effects rotation of lever 26 and cross shaft 24. Rotation of shaft 24 causes counterweight 22 to be raised and permits lifting rods 18 and ring-rail '14 to be lowered to the dotfing position. Manual release valve 84 is tripped by the operator thereby starting the flow of air to valve 88. When four-way valve 88 has been closed by air pressure thereon coming from valve 84 there is a reduction of pressure in conduits 102 and 104 through shuttle valve 100 and flow control 106 which permits the pressure in cylinder 56 to flow back toward quick release or quick exhaust valve 110. Once valve 110 has been partially opened it permits a rapid exhaust of the air contained within cylinder 56 and relieves the pressure on piston 54, piston rod 52 and linkage rod 40.

If for some reason, such as an emergency, it becomes necessary to lower ring-rail 14 before a full cycle of operation, valve 76 may be operated manually. Opening valve 76 permits air to flow into shuttle valve 100 and reverse the flow of air therethrough. The air is permitted 6 to flow into conduit 104 and into quick release valve and cylinder 56 to permit ring-rail 14 to be downed at any point desired by the operator.

The alternative embodiment of the invention shown in FIGS. 69 operates similarly to the embodiment shown in FIGS. 1-5. As ring-rail 14 moves upwardly in a reciprocating manner and bobbins 16 are built, ring-rail 14 finally contacts switch 226 to permit pressure therein to flow to four-way valve 220. Operation of valve 220 permits pressure from the source flowing through line 280 and permits the air pressure to flow into line 284 that switch 244 that is operated by cam 198. Once valve 244 is opened the pressure flows through line 246 into delay circuit 250 and into line 272 which connects delay circuit 250 with cylinder 156 to thereby effect movement of piston 154 in a downwardly direction, as shown in FIG. 8, and thereby shorten chain 158 to operate traverse rod 162 and lower ring-rail 14. Since pressure is continually on cut ofi? switch v280, cam 198 opens switch 280 and permits air pressure to flow into line 284 that operates control switch 286 to cut off the electric motor which has been operating the conventional spinning frame 12 and builder motion 170.

As pressure flows through line 272 to cylinder 156 and moves piston 154 the pressure flows through check valve 308 to motor 182 and pawl cylinder 306 to thereby operate pawl 186 and permit motor 182 to rotate shaft and take up on chain 168 to thereby hold traverse rod 162 in a position such that ring-rail 14 is in the lowered position.

Activation of reset valve 218 permits the operator to efiect winding or unwinding of traverse chain 168 by use of either switch 292 or 296. Manual operation of unwind switch 292 permits passage of air directly to motor 182 and permits rotation of shaft 180 in a direction such that chain 168 is unwound and, because of counterweight 22, ring-rail 14 is lowered. Manual activation of wind switch 296 permits air from line 290 to pass into motor 182 because check valve 308 prevents the air from flowing to cylinder 156.

Thus it is seen that the instant invention provides a simple and easily installed mechanism for automatically downing the spinning frame ring-rail without the necessity of considerable manual effort. The instant mechanism is not only easily and rapidly installed but is easily maintained and operates on an air supply which is readily available in the vicinity of presently known spinning frames. The invention is readily adaptable to presently known spinning frames and, because of the simplicity and complete pneumatic control, has extremely low maintenance requirements. The many adjustments that can be utilized in this system provide a versatile mechanism permitting any desired wrap-up configuration with the attendant advantages of reducing waste and increasing production in the various phases of textile production.

Many modifications and variations of subject invention are possible in 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 as new and desired to be secured by Letters Patent of the United States is:

1. In a spinning frame having a reciprocating member for building bobbins, an automatic ring-rail downing mechanism comprising:

pneumatic means for lowering the ring-rail to a dofiing position;

linkage means for connecting said pneumatic means to the operating mechanism of the spinning frame;

a rail switch for operating by the ring-rail;

a four-way valve connected with a source of pneumatic pp y;

said rail switch and said four-way valve interconnected for permitting the flow of pneumatic pressure through said four-way valve; and

pneumatic pressure from said supply source flowing through a regulator and said four-way valve into said pneumatic means for operation thereof upon activation of the rail switch, whereby, when the ring-rail reaches a certain position it activates said pneumatic control means to cause said pneumatic means to effect movement of said linkage means and lower the ring-rail to the dolfing position.

2. The automatic ring-rail downing mechanism of claim 1 wherein said linkage means includes a lever rigidly attached to the cross-shaft of the spinning frame; a linkage rod forming an extension of said pneumatic means; said lever and said linkage rod swivelly attached to one another.

3. The automatic ring-rail downing mechanism of claim 1 wherein said linkage means comprises: a chain means connecting said pneumatic means to the traverse rod of the spinning frame, whereby activation of said pneumatic means causes said chain means to move the traverse rod and lower the ring-rail.

4. In a spinning frame having a reciprocating member for building bobbins, an automatic ring-rail downing mechanism comprising:

a cylinder having a piston mounted therein;

said piston attached to a piston rod extending from said cylinder;

pneumatic conduit means attached to said cylinder for permitting pneumatic pressure to enter said cylinder and operate said piston and piston rod;

linkage means connecting said piston rod to the operating mechanism of the spinning frame;

a rail switch for operation by the ring-rail;

a manual release valve connected with a source of pneumatic supply; a four-Way valve connected with a source of pneumatic pp y;

said rail switch an release valve permitting the flow of pneumatic pressure to said four-way valve for operation thereof;

pneumatic pressure from said supply source flowing to said four-way valve and into said pneumatic means, whereby activation of said rail switch or said manual release valve effects operation of said pneumatic means to lower the ring-rail;

a lever rigidly attached to the cross shaft of the spinning frame;

a linkage rod forming an extension of said piston rod;

and

said lever and said linkage rod swivelly attached to one another.

5. The automatic ring-rail downing mechanism of claim 4 including traverse wind means for winding or unwinding the traverse rod chain to raise or lower the ringrail.

6. In a spinning frame having a reciprocating member for building bobbins, an automatic ring-rail downing mechanism comprising:

a cylinder having a piston mounted therein, said piston attached to a piston rod extending from said cylinder;

pneumatic conduit means attached to said cylinder for permitting pneumatic pressure to enter said cylinder and operate said piston and piston rod;

a chain means connecting said piston rod to the traverse rod of the spinning frame, whereby activation of said pneumatic means of said cylinder causes said chain means to move the traverse rod and lower the ring-rail;

a four-way valve;

a rail switch for activating said four-way valve;

a delay circuit for permitting adjustment of the time span between activation of said rail switch and said cylinder;

a cam switch for activation of said delay circuit;

a manual control valve for initiating operation of the system at any desired point;

a manual reset valve for returning the system to its beginning status; and

a motor cutoff switch for stopping the motor operating the spinning frame, whereby, when the ring-rail reaches a certain position, it activates said rail switch to effect lowering of the ring-rail to the doffing position and wherein the ring-rail may be lowered at any point in the stroke and any desired number of yarn wraps may be applied to the yarn package after said rail switch has been activated.

7. The automatic ring-rail downing mechanism of claim 6 including traverse wind means for winding or unwinding the traverse rod chain to raise or lower the ringrail.

8. The automatic ring-rail downing mechanism of claim 7 wherein said traverse wind means comprises: an air motor connected to the shaft of the pick gear; an air cylinder for release of the pawl to permit operation of the pick gear by said air motor; a wind switch; an unwind switch; said wind and unwind switches inserted in a pressure line leading to said air motor for selective operation thereof.

References Cited UNITED STATES PATENTS 2,503,099 4/1950 'Culbreath 57-54 2,575,031 11/1951 Smith 242261 3,074,224 1/1963 Kennedy et al 5754 3,101,585 8/1963 Andersen et al. 24226.1X 3,175,350 3/1965 Powell et al. 5754 3,336,739 8/1967 Sanders et al. 57-54 3,357,167 12/1967 Jones et al. 24226.1X

DONALD E. WATKINS, Primary Examiner US. Cl. X.R. 24226.2

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