US2989980A - Reel apparatus - Google Patents

Description

June 27, 1961 R. H. CULLEN TAL 2,989,980

REEL APPARATUS Filed Aug. 8, 1958 3 Sheets-Sheet 1 N N i Hexa/5er Hoa/gema INVENTORS ATTO/Q/VEVJ June 27, 1961 R. H. CULLEN ETAL 2,989,980

REEL APPARATUS Filed Aug. 8, 1958 3 Sheets-Sheet 2 Herbe/f H. /voa/ @man INVEN ORJ June 27, 1961 Filed Aug. 8, 1958 R. H. CULLEN ETIL` REEL APPARATUS 3 Sheets-Sheet 3 INV ENTOR5 United States Patent O 2,989,980 REEL APPARATUS Roy H. Cullen, 1710 1st City National Bank Bldg., Houston 2, Tex.; Leslie D. Richards, 5816B Harvey Wilson Drive, Houston 20, Tex.; and Herbert H. Hodgeman, 2339 McClendon St., Houston, Tex.; said Richards and Hodgeman assignors to said Cullen Filed Aug. 8, 1958, Ser. No. 754,065 5 Claims. (Cl. 137-355.26)

This invention relates to new and useful improvements in reel apparatus.

In the drilling of oil wells and the like with a drill bit supported on a hose or similar exible support, many difiicultes and problems arise at the surface of the well in connection with the handling and storage of the hose due to the fact that such hose is relatively heavy and large quantities of the hose must be available for rapid lowering or raising in the well. So far as' is known, no satisfactory apparatus for the handling and storage of such hose has been heretofore available.

It is therefore an object of this invention to provide a new and improved reel apparatus for the satisfactory storage and handling of hose and the like, and particularly hose which is relatively heavy and which is required in large quantities.

An important object of this invention is to provide a new and improved reel apparatus for coiling hose thereon and uncoiling hose therefrom while one end of the hose is Connected to a fluid line with the reel apparatus, whereby the coiling and uncoiling of the hose can be accomplished while maintaining fluid ow through the hose.

Another object of this invention is to provide a new and improved reel apparatus for the storage and handling of hose and the like, wherein a reel is mounted for lrotation about a substantially vertical shaft which is secured to the reel at the lower end only whereby obstructions at the upper end of the reel are eliminated.

A further object of this invention is to provide a new and improved reel apparatus wherein a reel is mounted for rotation about a vertical axis for feeding a hose or similar elongate exible member vertically into the reel for laying the hose or similar member in a plurality of horizontally disposed rows, and wherein means are provided for varying the speed of rotation of the reel to facilitate laying the hose or similar member in such rows.

A particular object of this invention is to provide a new and improved reel apparatus wherein a reel is driven by drive mechanism which may be readily varied in speed for properly laying a hose or similar member on the reel and which is capable of delivering a substantially constant torque to the reel at the different speeds.

Still another object of this invention is to provide a new and improved reel apparatus wherein a reel is mounted `for rotation on a vertical shaft with standard bearings, and wherein a separate swivel connection is provided between a non-rotatable fluid inlet pipe and a rotatable pipe coupling section, whereby the bearings support the load of the reel and hose therewith so that substantially no load is placed upon said swivel connection.

A still further object of this invention is to provide aV new and improved reel apparatus wherein a reel has a hub mounted on a non-rotatable vertical shaft for rotation of the reel, and wherein such hub and shaft are removable from the reel for repair or replacement Without moving the reel.

The preferred embodiment of this invention will be described hereinafter, together with other features thereof, and -additional objects will become evident from such description.

The invention will be Vmore readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof,

Patented June 27, 1961l Pce wherein an example of the -invention is shown, and wherein:

FIG. 1 is an elevation, partly in section, illustrating the preferred form of the apparatus of this invention;

FIG. 2 is a plan view of the apparatus shown in FIG. l;

FIG. 3 is an enlarged view, taken on line 3--3 of FIG. 2 and it shows in particular the details of the hub assembly of this invention; and

FIG. 4 is an enlarged view, partly in section and partly in elevation showing the details of a portion of the drive means illustrated in FIG. l.

In the drawings, the letter B designates generally the base or skid upon which the reel apparatus of this invention is adapted to be positioned for moving the same from place to place and for supporting the same during use. Briey, the reel apparatus includes a reel R which is mounted for rotation about a shaft 10. A hub assembly A is connected to the reel R through a spider frame S and the hub assembly A is positioned on the shaft 10 -to form the hub for the rotation of the reel R about the shaft 10. The reel R is rotated in either direction for the coiling and uncoiling of a hose H or similar member thereon by means of a drive means or mechanism D which is also preferably mounted on the base or skid B. During the rotation vof the reel R in either direction, one end of the hose H is maintained connected to a fluid flow line F so that fluid such as air, water or drilling mud may be introduced into the hose H or exhausted therefrom while the hose H is being coiled or uncoiled on the reel R.

Considering the invention more in detail, the base or skid B may be formed in numerous Ways, but preferably it is formed with parallel skid members 12 which are connected at their ends with pipes 14. The pipes 14 may be connected in any suitable manner to the skid members 12, but since the skid members 12 and the pipes 14 are preferably formed of steel or similar material, the pipes 14 would normally be welded to the skid members 12 to form a rigid substantially rectangular frame for the base B or skid. Additional laterally extending reinforcing plates 15 are positioned intermediate the ends of the skid members 12 `and are also Welded or are otherwise secured to the members 12. End plates 16 extend horizontally from one of the skid members 12 to the other at each of the ends thereof, and one of such plates 16 serves as a platform for the drive mechanism D (FIGS. l and Q) as will be more evident hereinafter.

For supporting the axle or shaft 10 on the Ibase or skid B, various types of supporting plates or members connected to the skid members 12 could be employed. But as illustrated in FIGS. 1 and 2, a laterally extending support plate 17 extends from one of the skid members 12 to the other and is welded or is otherwise connected to such members 12. The shaft or axle 10 is preferably formed with a lower laterally extending annular ange 10a which has a plurality of bolt or screw openings 10b, formed therethrough for receiving bolts or screws 18 as best seen in FIG. 3. The shaft or axle 10 is thus secured to the base or skid B and is non-rotatable. The shaft or axle 10 is formed with a central opening 10c` which extends vertically therethrough and which is aligned with a vertical opening 17a in the support plate` 17, for a purpose to be hereinafter described.

The external surface of the shaft or axle 10 is provided with an annular shoulder 10d so that a conventional ball bearing 19 surrounding the shaft 10 above such shoulder 10d is limited in its downward movement by the shoulder 10d. A resilient snap ring 20 or any other similar means may |be used for holding the bearing 19 in position on the shaft 10. Another ball bearing 21 which is also of conventional construction is mounted near the upper end of the shaft 10 and is prevented from moving downwardly with respect to the shaft byY an annular shoulder 10e. Bearing means other than the conventional ball bearings 19 and 21 illustrated in FIG. 3 could be employed. with this invention for mounting the hub assembly A on the shaft 10 for relative rotational movement vtherebetween, but the ball bearings 19 -and y21 are more economical since they `are conventional in construction and they are relativelyeasy to install initially and to subsequently remove for replacement or repair.

' The hub assembly VA which surrounds the shaft it! includes 'a 'cylinder 25 which is formed with a lower annular shoulder a for supporting a lower plate 26 having a resilient packing 27 therewith. The packing 27 may be formed of rubber or any other suitable sealing material which is adapted to provide a Huid tight seal with the lower portion of the shaft 10. A yring having a plurality of bolt holes 30a formed therethrough is welded at 3l or is otherwise secured to the lower portion of the external surface of the cylinder 2S. A similar ring 32 having bolt holes 32a formed therethrough is welded at 33 to the upper portion of the external surface of the cylinder 25. I'he ring 32 may also be welded to the upper edge of the cylinder 25 as indicated by the weld 34. The cylinder 2S is supported, along with the rings 30 and 32, in position around the shaftl by means of an upper support plate 36 which has bolt openings 36a therethrough. The .plate 36 is not welded to the cylinder 25 or the ring 32, but a plurality of bolts 38 extend through the openings 36a, 32a and 30a, and nuts 39 are provided on each end of each of the bolts 38 so that the cylinder 25 is directly bolted to the support plate '36 through the bolts 38. An annular seal ring 40 formed of rubber or other suitable sealing material is carried by the plate 36 for constant sealing engagement with the external surface of the shaft 10.

Above the plate 36, a bra-ke such as an electric brake E is provided for controlling the rotation of the hub assembly relative to the shaft 10 during the coiling and uncoiling of the hose H on the reel R. The brake E which is illustrated in FIG. 3 of the drawings is a conventional brake and is illustrated only as to its main parts. Therefore, as illustrated the brake E includes a lower brake drum 41 having an internal annular brake drum surface 41a. The drum 41 is secured to the plate 36 with bolts or screws 42 or other suitable securing means. The drum 41 thus rotates with the portion of the hub assembly A therebelow. Above the drum 41, and mounted for engage- :ment with the sur-face 41a, is a brake band y44 -founed of the usual brake band material such as asbestos. The band 44 is carried by a brake assembly ring l45 which includes the mechanism for imparting radial movement to the .band 44 for frictionally engaging it with the inside surface 41a of the drum 41 when desired. Such apparatus has not been illustrated in detail since it is conventional. The electrical leads or wires 46 for operating the brake E are shown in FIG. 3 and such wires 46 may be brought in through the opening 10c throughthe shaft 10 from a point below the hub assembly A so that rotation of the hub assembly A will not interfere with the wires 46. In any event, the upper `brake assembly '45 is secured to the shaft 10 with -a key 47 extending into a fixed sleeve 48 mounted on a plate-'49 which in turn is secured to the brake assembly 45. Bolts 50 are preferably used to connect the plate 49 and the sleeve 48 together. Therefore, the brake assembly and the .brake band 44 thereon are held against rotation when the brake drum 41 and the parts of the hub assembly A therebelow are rotating relative to the shaft 10. An'

annular shield 52 is secured to the sleeve 48 with bolts or screws 53 so as to cover the brake E as seen in FIG. 3. A central opening 52a is provided in the shield 52 in alignment with the opening'lc ofthe shaft 10, fora purpose to be hereinafter described.

The spider, frame S which extends `from the hub assembly A to the reel R includes aplurality of vertically extending trapezoid shaped 4plates 55 each of which has a rectangular shaped plate 56 welded or otherwise secured thereto. Each plate 55 has a tube 57 welded or otherwise secured thereto. Each tube 57 has an axial bore or opening 57a therethrough lfor receiving one of the bolts 38 therethrough to hold the vplates 55 in position on the hub assembly A as seen in FIGS. 1 and V3.

.An annular U-shaped pulley or track 60 is welded or is otherwise secured to the outer ends of the plates 56. Such pulley or track 60 is formed with an annular or circular channel 60a for receiving a drive belt 62, as will be more fully explained. Each of the plates 56 also has formed thereon or secured therewith an upper platform plate 63 which extends substantially horizontally or perpendicular to each plate 56. An inner frame of the reel R is mounted on the platform plates 63 and is composed of a plurality of vertically extending pipes or rods 65 which are secured at their lower ends to the platform plates 63 and are secured together at their upper ends by a circular pipe 66. The pipes 65 are preferably spaced apart so that there is one of such pipes 65 for each of the platform plates 63, although the number of pipes 65 may vary as desired for adequate strength and rigidity. An outer reel frame is provided with a similar construction which includes a plurality of vertically extending pipes or Vrods 67 which are welded or are otherwise secured to the platform Iplates 63V at their lower ends and which are welded or are otherwise secured to an upper annular pipe or rod 68. The number of the pipes or rodsr67 may be varied as desired, but preferably there will be one pipe or rod 67 for each of the platform plates `63. Such construction provides for rigidity while at the same time permitting visibility of the hose H when it is coiled between the inner and outer reel frames. Additional outer reinforcing bands 70 which encircle the outer reel `frame and which are welded or are otherwise secured thereto may be used for additional rigidity and closure if desired. The reel frames thus provide an open annular space 75 therebetween with the open upper endy 75a into which the free end of the hose H is fed during the coiling and uncoiling of the hose H on the reel R.

The drive mechanism D is illustrated in FIG. 1, and internal details are illustrated for a portion of the mech- `anism D in FIG. 4. A bracket 76 which is welded or otherwise secured to the plate 16 holds the drive mechanism D for electing a driving of the drive belt 62. Such bracket 76 carries conventional pillow block bearings 77 for rotatably mounting a pulley shaft 78 thereon. Such shaft 78 has a pulley or sheave 79 mounted on its lower end for engagement with the inner surface of the drive belt 62. A -gear reducer assembly, an example of which is particularly illustrated in FIG. 4 of the drawings, is used for imparting rotation from a hydraulic motor 80 to the-shaft 78 for driving the pulley 79. The motor SG is preferably a hydraulic motor since it is capable of supplying a constant torque at variable speeds, although other types of motors may be utilized within the scope of this invention. A shaft 81 is driven by the motor 80. The gear reducer includes a gear 82 mounted on the shaft 81 and a larger'gear 83 mounted on the shaft 78. A key 82a is used for connecting the gear 82 to the shaft 81. In the case of the gear 83, an additional sleeve 84 is prefably provided around the shaft 78 and inside of the gear 83. A key 84a connects the shaft 78 to the sleeve 84 and a key 83a connects the sleeve 84 to the gear 83, so that the shaft 78 is connected to the gear 83. The sleeve 84 Yhas la lower annular ange 84b which rests upon the pillow block bearing 77 to limit the downward movement of the entire assembly with respect to the support bracket 76. The gear reducer has an exterior housing 86 which is connected to a bracketV 85 land which -retains bearings 87 and 88 around the shafts 78 and .81, respectively, to permit a swinging or pivoting of the housing 86 about the shaft 78. Since the bracket 85 is connected to the housing 86 by welding or other suitable means, the shaft 78 in effect serves as a pivot point for the bracket 85 `and the hydraulic motor 80 and other parts mounted therewith. An idler pulley or sheave 89 is mounted on the bracket 85 for engagement with the external surface of the belt 62 (FIG. 2) to tighten the belt 62 to assure a proper frictional drive with the drive sheave 89 and circular track 60. The bracket 85 and the parts mounted therewith are rotated about the bearings 87 and the shaft 78 to the desired position with the pulley or sheave 89 in engagement with the outside surface of the belt 62 by a turnbuckle adjusting member 90 ofV conventional construction which is connected with the bracket 85 and also with the base B. Therefore, the bracket or frame 85 and the pulley or sheave 89 therewith may be moved inwardly or outwardly with respect lto the belt 62 for adjusting the tightness of the belt 62 by merely adjusting the turnbuckle 90 as desired.

For maintaining a supply of uid to the hose H while the hose H is being coiled and uncoiled on the reel R, the uid ow line assembly F includes a rotatable pipe section and a non-rotatable pipe section which are connected together with a swivel. The rotatable pipe section is preferably connected with the reel R and it includes pipes 92, 93 and the elbow 94 therebetween. A suitable coupling 95 of known construction is provided at the end of the pipe 93 for coupling the inner or fixed end of the hose H to the flow line assembly F. Such connection provided by the coupling 95 with the hose H remains connected at all times during the rotation of the reel assembly R except when it is desired to completely remove the hose H from the reel R. A swivel 96 is provided at the end of the pipe 92 which is in the central portion of the reel R and which is substantially directly above the opening 10c in the shaft 10. The non-rotatable pipe section of the flow line assembly F includes a pipe 97 having its upper end connected to the swivel 96 and its lower end connected to a pipe 98 through an elbow 99. A laterally extending inlet pipe 100 may also be provided on the base B so that connection with a fixed fluid source may be made at either end of the pipe 100 for supplying uid to the fluid flow line assembly F yas desired. The pipe 97 extends downwardly through the opening 10c of the shaft 10 and also through the opening 17a of the plate 17 to the intermediate area within the base B as best seen in FIG. l. The swivel 96 is formed in any conventional manner, but since it is not required to support any weight, it can be a relatively light type of swivel, and one form is illustrated by way of example in FIG. 3 of the drawings wherein the swivel is shown as having `an -annular lower ange 96a which fits within a collar 96h which is threaded or otherwise connected to the upperend of the pipel 97. Additional clamps or braces may be provided for the various pipes of the flow line assembly F- as desired for strengthening and supporting same.

The operation or use of the apparatus of this invention is believed to be evident from the foregoing description. Several features of the invention should be noted however. 'I'he reel R is rotated with the drive mechanism D, as explained previously,and in order to lay the hose H in a plurality of rows which are gradually stacked in horizontal layers between the inner reel frame and the outer reel frame, the speed of the motor 80 is varied to accomplish the proper positioning of the hose H in the horizontal rows. For that purpose, it is desirable to have a hydraulic motor which provides a constant torque with the variable speed so that even though the speed of the reel R is varied, the torque remains constant so that the relatively heavy hose may be handled and the relatively heavy reel R may be turned. The hose H may be fed into the annular space 75 between the reel frames from any direction vertically, or substantially vertically above the reel R. All of the apparatus is positioned below the upper end of the reel R so that there is no interference from any part of the apparatus when the hose H is fed into or out of the reel R. Under normal operation, it should be understood that the hose H is not actually pulled onto the reel R, but instead is merely fed into the annular space 75 so that it is laid in position in a coil without placing the hose H under any appreciable amount of tension or strain. Such feedingof the hose H to the open annular space 75 between the reel frames of the reel R may be done by hand or any other suitable apparatus. During such feeding of the hose into the annular area 75 of the reel R, or the feeding of such hose H therefrom, fluid may be supplied constantly to the hose H throughthe fluid ilow line assembly F.

Also, when the hose H is nolonger being fed to the reel R, the reel R can be readily stopped with the brake E which is electrically controlled in the preferred embodiment of this invention. Such brake E acts to stop the hub assembly A from rotating and therefore to stop the reel R from rotating. l

It is to be noted that the frame S connecting the reel R to the hub assembly A is not directly welded to the hub assembly A since the connecting bolts 38 are utilized. Therefore, the extreme heat of welding directly to the hub is prevented and distortion of the shaft 10 by reason of such welding heat is avoided. Furthermore, the hub assembly may be removed from the shaft 1li for the repair or replacement of the bearings 19 and 21 Without removing the reel R from the base B. Such can be readily accomplished by initially supporting the reel R on blocks positioned below the plates 56 on the skid members =12 or other parts thereof directly below the plates 56. With the reel R thus supported on the base B directly, the swivel 96 is disconnected and the pipe 92 is moved out of the way of the hub assembly A. Then, the bolts 53 are removed and the shield 52 is lifted upwardly away from the pipe 97 and may be completely removed. rI'he nuts 39 on the bolts 38 are then released which permits the raising of the support plate 36 upwardly with the brake E and all of the parts thereon so as to expose the bearing 21 so that it also can be removed from the shaft 10. If the bearing 19 is also to be removed for replacement or repair, the snap ring 20 may then be removed and bearing 19 lifted out of its position. The reverse procedure would be followed forreassembling the hub assembly A on t-he shaft 10 and for connecting the frame S to the hub assembly A. It can thus be seen that the bearings 19 and 21 are accessible for replacement or repair without requiring the lifting or removal of the reel R. Suchfeature is extremely important in the normal use of the invention with very large hose since the reel R then is extremely large and is diicult to handle without special hoisting equipment. Itv

and 19 during the rotation of the reel R with respect toV the shaft 10 so that none of such weight is supported by the swivel 96. Therefore, relatively large bearings 19v and 21 may be provided for supporting the relatively heavy load without'affecting the size of the swivel 96- in any way since the swivel `96 does not bear any part of the load of the reel R or the hose H or any of lthe mechanism that rotates with the reel R.

The -foregoing disclosure and description of the invention is illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.

What is claimed is:

1. A reel apparatus for hose and similar members, comprising a shaft positioned substantially vertically, a reel having an outer substantially cylindrical frame and an inner substantially cylindrical -frame with an annular Space therebetween and with a central opening inwardly of said inner frame said annular space being a radial Vdistance greaterthan the Vdiameter of the hose beinghandlecl, the upper and of said annular space being fully open to receive and discharge the hose, said shaft extending into said opening so that said reel ,is positioned with said inner frame surrounding saidVsha-ft, a hub assembly mounted on said shaft `for rotation thereon and relative thereto, connection means extending from said hub assembly to said inner frame for connecting said reel for rotation relative to said shaft, a stationary uid flow line mounted with said rcel and extending through said shaft, and meansrwith said reel for connecting one end of a hose or similar member on said rcel to said uidrflow line for maintaining fluid ow through the Ahose during rotation of the reel relative to the shaft, the areaV above the central area dened by said inner frame being open and unobstructed to prevent4 interference with the hose as it is wound and unwound on said reel.

2. A reel apparatus for coiling and uncoiling hose and similar members thereon, comprising an inner substantially cylindrical reel frame, an outer substantially cylindrical reel frame disposed concentrically around said inner frame to form an open annular space therebetween having a lower end and an upper end, an annular end section connecting said inner frame to said outer frame at the lower end of said open vannular space to provide a support for hose as it is coiled and uncoiled in said annular space while leaving the other end of said open annular space fully open for the hose as it is ed to or from the annular space for coiling or uncoiling, a hub assembly positioned internally of said inner reel trame, a connecting frame connected from said hubassembly to said inner trame at the end thereof adjacent said annular end section only, a shaft positioned internally of said inner frame and having said hub assembly mounted thereon for rotation of said hub assembly thereon and relative thereto, an annular ring having connection with said annular end section on said reel frames, a stationary uid line mounted with said reel and extending through said shaft, and a drive means including a flexible endless belt around said `annular ring and in driving engagement therewith for driving said reel -frames and said hub assembly relative to said shaft. Y

3. The structure set forth in claim 2, wherein said connecting frame includes a plurality of radial plates each of which has :an inner end, a sleeve on said inner end of each of said radial plates, and wherein the connection between said connecting frame and said hub assembly includes a plurality of bolts mounted on the hub assembly and extending through each of said sleeves on said connecting trame, whereby the reel frames are mounted on said hub assembly without welding said connecting trame to said hub assembly.

4. A reel apparatus for coiling and uncoiling hose and similar members thereon, comprising an inner substantially cylindrical reel frame, an outer substantially cylindrical reel frame disposed concentrically around said inner frame to lform an open annular space therebetween which is greater in radial width than the diameter of the hose being handled, an annular end section connecting said inner frame to said outer `frame atone end of said open annular space to provide a support for hose as it Vis coiled and uncoiled in said annular space while leaving the other end of said open annular. space open for the Ihose as it is fed to or from the annular space .for coiling or uncoiling, a hub assembly positioned Vinternally of said inner reel frame, a connecting frame connected from said hub assemblyto said inner frame at the end thereof adjacent said annular end section only, 'a shaft having said -hub `assembly mounted thereon 'for rotation of said hub assembly relative thereto, bearings between said shaft and said hub assembly, a non-rotatable uid flow line extending through said shaft, a rotatable ow line connected to said reel frames for'coupling to one end of the hose positioned in said openv annular space between said frames, and a swivel connection between said non-rotatable ow line and said rotatable flow line which is separate from said bearings to prevent the application of the load of said reel frames and parts therewith on said swivel connection. y

5. A reel apparatus for coiling and uncoiling a hose or similar member thereon, comprising a reel for Vreceiving the hose or similat member, support means for supporting said reel for rotation, a drive means connected to said Vreel and including an endless drive belt,'a track on said reel engageable by said endless drive belt for rotating said reel when said belt is moved by said drive means, and said drive means including a rotatable axle mounted on said support means and having a'gear and pulley thereon, said pulley being engageable with said endless belt so that rotation of said pulley causes said belt to move Ifor imparting rotation to said reel, a drive motor having a gear in coacting engagement with the gear on said axle for driving said axle and said pulley to thereby rotate said reel, a bracket connected to said motor, means connecting said bracket to said axle for permitting rotational movement of said bracket Vand said motor together relative to said axle, a tightener pulley mounted on said bracket in engagement with the external portion of said belt, and means for moving said bracket and said tightener pulley towards and away from said belt to adjust the tightness of said belt while maintaining said gears in meshing engagement.

References Cited in the le of this patent UNITED STATES PATENTS 538,950 Casson Mayv7, 1895 720,228 Couch Feb.Y 10, 1903 1,350,205 Anderson Aug. "17, 1920 1,532,177 Gist Apr. 7, 1925 1,612,206 Nicholson Dec. 28, 1926y 1,790,755 Lally Feb. 3, 1931 E1,971,165 YParker Aug; 21, 1934Y 2,300,243 Zierden Oct. 27, V1942 2,573,868 Newell Nov. 6,1951 A2,595,655 Hannay May 6,V 1952 2,599,423 Ziegler June 3, 1952 2,669,483 Fletcher Feb. 16, 1954 2,872,246 Zierden Feb. 3', "1959' v, FOREIGN PATENTSY ,Y j..

387,604 Great Britain Feb. 9, 1,933

Images