US3920084A

US3920084A - Extendable and retractible material delivery devices

Info

Publication number: US3920084A
Application number: US503287A
Authority: US
Inventors: Jr Wayne B Russell
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-11-21
Filing date: 1974-09-05
Publication date: 1975-11-18
Anticipated expiration: 1992-11-18

Abstract

An extendible and retractible boom or conduit comprises a number of shaft or boom members on a common longitudinal axis, each except the outermost member being telescoped within the one next adjacent. Each telescoped member has a piston slidably sealed to the inner wall of the next adjacent outer member to form a series of tandem-arranged sealed pistons. Fluid passageways are provided between adjacent shaft members so that fluid supplied under pressure to a port of the device flows through the passageways to all the piston heads, thereby extending the telescoped shaft members and at the same time driving fluid out from under each piston through fluid passageways to another port of the device. When the pressurized fluid flow is reversed to send pressurized fluid to the under sides of the pistons, the telescoped members are retracted and fluid above the pistons is driven out through the first-mentioned port. A conduit for conveying fluid or other material enters the device above the piston heads and tubular members attached to one or more of the pistons move with the pistons to effectively extend the length of the conveying conduit when the piston members are extended. Thus, the material or fluid can be ejected from the delivery end regardless of the length of extension of the device. In another embodiment, a second material or fluid conveying conduit, also extendible and retractible with the extension and retraction of the device, is adapted to retrieve the material or fluid delivered through the other conduit, such as for example in the case of earth drilling or well drilling operations where fluid may be forced down to the drilling member and then retracted and recirculated.

Description

United States Patent [191 Russell, Jr.

[ Nov. 18, 1975 1 1 EXTENDABLE AND RETRACTIBLE MATERIAL DELIVERY DEVICES [76] Inventor: Wayne B. Russell, Jr., 3895 Lugo Ave., Lynwood, Calif. 90262 22 Filed: Sept. 5, 1974 21 Appl. No.: 503,287

Related US. Application Data [63] Continuation-in-part of Ser. No. 418,073, Nov. 21, 1973, which is a continuation of Ser. No. 177,592, Sept. 3, 1971, abandoned.

[52] US. Cl. 173/79; 92/52; 92/53; 92/80; 92/31 [51] Int. Cl. B25D 17/14; E21C 7/00 [58] Field of Search 92/51, 52, 53, 62, 65, 92/108, 112, 80, 31; 173/79; 64/23 [56] References Cited UNITED STATES PATENTS 1,626,277 4/1927 Gartin 173/79 X 1,908,734 5/1933 Cuthill 173/79 X 2,288,545 6/1942 Osgood 173/79 X 3,180,236 4/1965 Beckett 92/177 X 3,603,207 9/1971 Parrett 92/108 X 3,610,100 10/1971 Hoffman... 92/108 X 3,696,712 lO/l972 Sung 92/52 3,768,578 10/1973 Russell, Jr 92/53 X 3/1974 Klein 92/52 X Primary E.\-aminerMartin P. Schwadron Assistant Examiner-Abraham Hershkovitz Attorney, Agent, or FirmDonald D. Mon

[ ABSTRACT An extendible and retractible boom or conduit comprises a number of shaft or boom members on a common longitudinal axis, each except the outermost member being telescoped within the one next adjacent. Each telescoped member has a piston slidably sealed to the inner wall of the next adjacent outer member to form a series of tandem-arranged sealed pistons. Fluid passageways are provided between adjacent shaft members so that fluid supplied under pressure to a port of the device flows through the passageways to all the piston heads, thereby extending the telescoped shaft members and at the same time driving fluid out from under each piston through fluid passageways to another port of the device. When the pressurized fluid flow is reversed to send pressurized fluid to the under sides of the pistons, the telescoped members are retracted and fluid above the pistons is driven out through the first-mentioned port. A conduit for conveying fluid or other material enters the device above the piston heads and tubular members attached to one or more of the pistons move with the pistons to effectively extend the length of the conveying conduit when the piston members are extended. Thus, the material or fluid can be ejected from the delivery end regardless of the length of extension of the device. In another embodiment, a second material or fluid conveying conduit, also extendible and'retractible with the extension and retraction of the device, is adapted to retrieve the material or fluid delivered through the other conduit, such as for example in the case of earth drilling or well drilling operations where fluid may be forced down to the drilling member and then retracted and recirculated,

15 Claims, 9 Drawing Figures US. Patent Nov. 18, 1975 Sheet 1 of6 3,920,084

K V l US. Patfint Nov. 18,1975 Sheet20f6 3,920,084

US. Patent Nov. 18, 1975 Sheet 3 of6 3,920,084

US. Patent Nov. 18,1975 Sheet4of6 3,920,084

US. Patent Nov. 18, 1975 Sheet 6 of6 3,920,084

EXTENDABLE AND RETRACTIBLE MATERIAL DELIVERY DEVICES This is a continuation-in-part of application Ser. No. 418,073 filed Nov. 21, 1973 as a continuation of application Ser. No. 177,592 filed Sept. 3, 1971 now abandoned.

This invention relates to extendible and retractible material delivery equipment, and more particularly to such equipment capable of being extended linearly from a relatively short length to a substantially greater length and being contracted or retracted to its minimum length.

In my said co-pending US. Pat. application Ser. No. 418,073 there is shown and claimed a shaft or boom arrangement especially adapted for providing rotational torque for earth drilling purposes. The shaft or boom comprises a number of telescoped members within an outer member, each telescoped member having a piston slidably sealed to the inner wall of the next adjacent outer member to form a series of tandem-arranged sealed pistons. Fluid passageways are provided between adjacent shaft members and a pair of fluid ports are provided through the outer member so that pressurized fluid may be sent into one of the ports and caused to flow through the system so that the pressurized fluid is applied to all the pistons in the direction which telescopically extends each shaft member relative to the next outer shaft member, in the direction which extends the length of the shaft. When the direction of fluid pressure is reversed so that the pressurized fluid flows into the other of the ports, the pressurized fluid is applied to the under side of each of the pistons so that each shaft member which is within another member slides in the direction which contracts the overall length of the shaft or boom toward its minimum length.

In my co-pending US. Pat. application Ser. No. 494,196 filed Aug. 2, 1974 there are also shown shaft or boom arrangements having multiple telescoped members which are extendible and retractible and may be rotated.

In Soderstrom US. Pat. No. 3,705,083 issued Mar. 29, 1955 there is also shown an extendible and contractible telescoped shaft arrangement, which however is not adapted for rotational torque.

It is an object of the present invention to provide conduit means for the delivery of material through a boom or shaft which is extendible and retractible so that the arrangement can be used to deliver the material at any distance from the material loading end of the shaft, which lies between the minimum and maximum length of the boom or shaft.

The invention is carried out by utilizing an extendible and retractible boom or shaft arrangement of the general type noted above to which there is attached a material conveying conduit extending into the casing of the device. The piston members of the device are provided with one or more members which telescope relative to the material conveying conduit, and can slide longitudinally relative to the conduit. Material conveying conduit means related to the piston members increases the effective length of the said conduit when the piston members are extended. At the end of the ma terial conveying conduit means opposite the loading end of the said conduit there is provided a delivery opening through which material introduced into the conduit at the loading end is expelled.

In one embodiment of the invention no provision is made for returning or recirculating the delivered material.

In another embodiment provision involving the use of two conduits is made for ejecting the delivered material and returning it to a position near the loading end, or recirculating it.

According to an optional feature, provision is made for rotating the shaft or boom members so that the device can be used where rotation is required, such as for example for a drill Kelly on which an auger drill will be attached to the extendible shaft. In such case, it is often desirable to supply lubrication such as water or mud to the drill, which may be done by use of the delivery conduit or conduits. In such arrangements it is often desired to collect or recirculate the liquid or mud delivered to the drill, in which case the embodiment providing for collection of the ejected material may be used.

According to another objectional arrangement no provision is provided for rotation, in which case the device may act as a non-rotating extendible boom capable of delivery material.

Devices according to this invention have many uses other than in a drill Kelly as will become apparent from the following description.

The foregoing and other features and aspects of the invention will be better understood from the following detailed description and the accompanying drawings of which:

FIG. 1 is an elevation view, partly in cross-section taken at line l1 of FIG. 2 and line la-la of FIG. 3, of a rotatable multi-stage extendible and retractible material delivery device according to this invention;

FIG. 2 is a cross-section view taken at line 22 of FIG. 1;

FIG. 3 is a cross-section view taken at line 33 of FIG. 1;

FIG. 4 is an elevation view, partly in cross-section taken at line 44 of FIG. 5, and line 4a4a of FIG. 6, showing a rotatable material delivery device somewhat similar to that of FIG. 1 but differing from FIG. 1 in having provision for return or circulating flow of the material;

FIG. 5 is a cross-section view taken at line 5--5 of FIG. 4;

FIG. 6 is a cross-section view taken at line 6-6 of FIG. 4;

FIG. 7 is an elevational cross-section view of an injection device somewhat similar to that of FIG. 1 but without provision for rotational drive;

FIG. 8 is a cross-section view taken at line 8-8 of FIG. 7; and

FIG. 9 is an end view looking from line 99 of FIG. 7.

Referring to FIGS. 1, 2 and 3 there is shown a multistage extendible and retractible shaft or boom arrangement adapted to be driven in rotation and provided with conduit means for delivering material. The arrangement is adapted for any of a number of uses, one of which is as a Kelly drive in an earth drilling operation. It is shown extendible in a downward direction which will be its normal position for earth drilling, but it should be understood that it is capable of uses other than earth drilling and may be used in other positions than that shown in FIG. 1. The mechanism comprises a stationary outer cylindrical or tubular shaft member 10 concentric with a longitudinal axis 9 and provided with a closure 11 at the top. At the lower part of member 10 its structure is brought outward at position 12 to form an outwardly extending gear housing 13 having an internal cavity 14 containing a pinion 15 fastened to a vertical shaft 16 extending upwardly through the upper wall of housing 13 and attached to the shaft of a motor 17 mounted on the upper surface of gear housing 13, which drives the pinion. The member 10 and the gear housing will be held stationary by mounting on a suitable bed or frame represented at 18, for example the platform of a drill rig when used for drilling. Within the section 12a outstanding from the tubular member 10 and within the gear housing there is a member 19 having an outer cylindrical surface concentric with axis 9, adapted for rotation relative to cylindrical member 10 and the gear housing, by provision of bearings 20 and .21 positioned between the gear housing and cylinder 19. These bearings are of a conical type adapted to withstand radial forces and also longitudinal thrust. There is attached to the outer cylindrical surface of member 19 a gear 24 which meshes with pinion 15 so that rotation of the motor 17 rotates member 19 relative to tubular member 10. Seals 22 and 23 serve to prevent the escape of oil from the cavity 14 of the gear housing, which is ordinarily present to lubricate the gears and bearings. A large extent of the inner surface of member 19 is formed in the shape of a square 19a, as best seen in FIGS. 1 and 2.

A cylindrical piston 25 is placed concentrically within cylindrical member 10 near the upper end of member 10 and is free to slide longitudinally with an annular seal 51 relative to member 10. Piston 25 comprises a member 25 which extends inwardly to a conical bearing 27 placed between the member 25 and another portion 250 of the piston, having attached to it an annular disc-like portion 26 having an outer periphery substantially at the inner cylindrical surface of member 10. The under surface of member 26 is attached to the upper end of a shaft or boom member which is double-walled at its corners as best seen in FIG. 3.

There is fixed within the cylindrical member 10 a cylindrical or tubular conduit 28 fixed relative to member 10 by being fastened to closure 11. The conduit 28 is concentric with the cylindrical side of member 10 and is co-axial with the longitudinal axis 9. The conduit 28 extends from a position above the closure 11 and passes down through the cylindrical member 10 to a position approximately in the region of the lower part of the gear housing 13.

There is attached to the portion 25a of piston 25, an annular piston portion 25b located between the annular portion 250 and the outer circumference of conduit 28. This portion 25b is provided with an internal annular groove 29 in which there is placed an annular seal 31 which seals the piston portion 25b to the tube 28 while permitting longitudinal sliding of the piston member 25b relative to the conduit. A cylindrical or tubular member 32 is integrally attached to the piston portion 25b, this cylindrical member being concentric with the conduit 28 and spaced from the outside surface of the conduit.

Although the bearing 27 permits relative rotation between

piston members

25 and 25a, the bearing nevertheless holds

piston members

25 and 25a together so that no relative longitudinal movement is permitted between the two

portions

25 and 25a. The seals 51 and .31, however, permit the entire piston consisting of parts 25 25a and 25b to slide longitudinally relative to outer cylinder 10 and the conduit 28 so that the shaft member 30 and the cylinder 32, attached to the piston,

can move longitudinally with the piston.

Beneath the piston portion 26 and between the

members

30 and 32 there is located a second piston head 33 sealed to the inner cylindrical wall 30bof member 30 by a seal 34, and to the cylinder 32 by a seal 35. There is attached to piston head 33 a shaft or boom member 36 concentric with axis 9. Member 36 is double-walled at its corners, comprising outer wall 36a and inner wall 36b. Within the inner wall 36b and spaced at some distance from wall 36b there is an inner cylindrical wall 37 concentric with axis 9 and attached to piston head 33.

In the annular space between

walls

36b and 37 and beneath piston head 33 there is a third piston 38 sealed to inner wall 36b by a seal 39 and to the wall 37 by a seal 40. A cylindrical member 41 attached to piston head 38 is co-axial with axis 9 and spaced between wall 36b and wall 37.

It is recognized from the foregoing description that piston 25 is slidable with its member 30, longitudinally relative to the fixed casing 10 so that the lower end of the member 30 can be extended downward beyond the member 19. Likewise piston 33 with its member 36 and inner member 37 is slidable downward relative to piston 25 so that the

members

36 and 37 can be projected downward beyond the lower end of member 30. Similarly, the piston 38 can be moved downward relative to piston 33 and its member 41 thus extended well beyond the lower end of member 36.

At its lower end, the member 30 is formed as a solid square portion 300 of which both the inner and outer surfaces are square as best seen in FIGS. 1 and 2, at the upper end of which the doubled walls 30a and 30b terminate. Likewise, at its lower end the wall 36 is formed as a solid square section 36c of which both the inner and outer walls are square, as can be seen in FIGS. 1 and 2. The outer surface of wall 41 is formed as a square 41a and its inner wall is formed as a cylinder 41b as can be seen in FIGS. 2 and 3. The dimensions of the

squares

19a, 30c, 36c and 41a are such that the dimension of each outer square surface conforms with the dimension of the square inner surface of the next outer' member, so that member drives member 300 which in turn drives member 36c which in turn drives member 41a, in rotation when the motor 17 is running. Hence, it is seen that the

members

30, 36 and 41 are not only slidable longitudinally to be extended as a shaft or boom but also rotate in unison so that the entire extended shaft or boom is rotatable. To facilitate the slidability, there is provided a seal 42 between square 30c and 360 and a seal 43 between squares 36c and 41a.

The lower end of member 41 is provided with a closure 44 through which there is a concentric opening 45 aligned with axis 9 and conduit 28 so that material which may be injected into the upper end of tube 28 can exit through opening 45 in any position of retraction or extension of the extendible members.

For the purpose of extending and retracting the mechanism there is provided a hydraulic system. This comprises a fitting or port 52 through the upper end of the casing wall 10 which communicates with region 53 above the piston 25 so that an inlet conduit 54 connected to the fitting 52 can supply hydraulic fluid under pressure above piston 25. The conical bearing 27 is of a type which provides a passageway 55 providing communication between region 53 and a space 56 between

members

25 and 26. A passageway 57 through the piston member 26 communicates between space 56 and a I space 58 between

pistons

25 and 33. A passageway 59 through piston 33 provides communication between space 58 and a space 60 between piston heads 33 and 38.

A fitting or port 61 near the lower end of casing provides communication from the exterior to the space 62 between casing 10 and outer wall 30a of the doublewall member 30. Ports 63 communicate between region 62 and the spaces 64 between walls 30a and 3012. At the lower end of wall 30b there are provided through it ports 65 providing communication between spaces 64 and space 66 between

member

30 and 36. At the upper end of wall 36a there are ports 67 providing communication between space'66 and the spaces 68 between

walls

36a and 36b. At the lower end of wall 36b there are provided ports 105 between spaces 68 and the space 106 between

walls

36b and 41.

The hydraulic fluid for expanding and retracting the boom or shaft is contained in a tank 70 shown in phantom from which a conduit 71 shown in single-line form connects with conduit 54, and another conduit 72 communicates between the tank and conduit 73 attached to fitting 61. A pump 74 serves to pump fluid from the tank either in the direction of arrow 75 or arrow 76 depending on the setting of the pump. Assuming the pump is set to force hydraulic fluid in the direction of arrow 75, the fluid enters through fitting 52 to region 53 from where it enters

regions

58 and 60 to force the pistons and their shaft members to slide downward as shown in FIG. 1 to extend the shaft members which may act as a shaft or boom. Fluid in the system during this expansion is thereby forced out through fitting 61 and back to the tank in the direction of arrow 77. When it is desired to retract the cylinders the pump is set to force fluid from the tank in the direction of arrow 76 through fitting 61 and into region 62 below piston 25. The fluid flows through ports 63 into regions 64 from whence it flows through the ports 65 into region 66 and then through ports 67 into regions 68 from where it flows through ports 105 into region 106 below piston 38. The force of the hydraulic fluid flow in this direction pushes all the piston heads and their shaft members upward toward the top closure 11 to the retracted position shown in FIG. 1, and fluid located above the pistons is thereby forced out of the casing through fitting 52 and back to the tank in the direction of arrow 79.

When the shaft or boom is extended the

conduit members

32 and 37 are similarly extended because of their attachment to the

respective pistons

25 and 33. Thus the conduit 28 is extended by the

members

32 and 37, which in order to prevent leakage of material between the conduit members or sections, are provided with the

respective seals

31 and 35. Regardless of what position the pistons and their shaft members are in respect to extension or retraction, any fluid or material sent into the top of conduit 28 will be forced out through opening 45.

Such a system can have many uses, an important one which is as an earth drilling equipment in which liquid or mud or the like is supplied to the drilling area. In such case a suitable drilling bit or auger will be attached at the lower end of cylinder or shaft member 41 in a well-known manner to perform the drilling by useof the motor 17 to rotate the auger. During the drilling operation the fluid material may be forced down through

conduits

28, 32 and 37 and out through opening 45 to the region of the drilling.

The embodiment shown in FIGS. 4, 5 and 6 is also equipped with an extendible boom arrangement and with means for rotating it. It has a material injection arrangement which differs from that shown in FIGS. 1, 2 and 3 in that provision is made for collecting the material which is injected, which is advantageous in some uses such as for example in earth drilling where it is desired to inject fluid or mud or the like to the drilling region and then withdraw it from that region. The arrangement comprises a cylindrical casing 10a provided with an upper closure 1 1a, a gear housing 13a in which there is a pinion 15a drivable by a motor 17a, which drives a gear 24a mounted on the periphery of a rotat able cylindrical member 19a rotatable relative to the gear housing by bearings 20a and 21a, in a manner analogous to corresponding parts shown in FIGS. 1 to 3. In a manner analogous to FIG. 1, there is a piston 25a within the cylinder 10a having attached to it a double-walled member 30 and also to a cylindrical member 32. The

members

30 and 32 are adapted to rotate relative to piston member 25a by means of a conical bearing 27a, and the piston is adapted to slide longitudinally relative to casing 10a. A second piston member 35a attached to a cylindrical member 41a is located below the piston 25a. A fitting 52a communicates with space 53a above piston 25 a and afitting 61a communicates with region 62a.

It will be recognized that this piston arrangement comprising two pistons within thecasing, operates in a manner analogous to the three-piston arrangement shown in FIG. 1. When hydraulic fluid from tank 700 is forced through fitting 52a through conduit 71a into region 53a above piston 25a, this fluid passing through duct 27 of the bearing 27a and on through passageway 59a to the region above piston 35a, forces the two pistons downward relative to the casing and to each other to extend the boom or shaft in a manner analogous to that described in connection with FIG. 1. To retract the extended boom or shaft the hydraulic fluid is forced through conduit 72a and fitting 61a to region 62a so that it flows through ducts 67a to the spaces between the double walls of member 30 from where it flows through ducts 65a into the space between

members

30 and 41a, thereby forcing both pistons to retract to their position shown in FIG. 4.

Rotation of the boom or shaft is provided in a manner similar to that shown in FIGS. 1 to 3, namely by means of squared members 19a, 30c and the squared periphery 4111 The material injection system in the embodiment of FIGS. 4, 5 and 6 comprises a double-walled cylindrical conduit comprising an outer wall 81 and an inner wall 82 spaced within the outer wall to leave an annular space 83 between them. The walls of this conduit are concentric with the

members

30 and 41a and with the central longitudinal axis 9a. The walls of member 80 are fixed to the upper closure 11a and the space 83 between them communicates with a space 84 within a manifold 85 having a port or opening 86 for flow of material. The lower end of space 83 communicates with a region 87 above closure 44a attached to the lower end of cylindrical member 41a. An opening 88 through closure 44a serves to pass material flowing through conduit 80.

Within the wall 82 there is slidably fitted a cylindrical conduit member 90, open at both ends, and provided at its upper end with an outwardly extending flange 91 having a peripheral recess 92 containing an annular seal 93 for slidably sealing the cylinder 90 to the wall 82. At the lower end of cylinder 90 there is provided an inwardly extending flange 94 having a recess 95 containing an annular seal 96 which slidably seals the cylinder to an inner cylindrical conduit member 97 concentric with conduit member 90 and with axis 9a and attached at its lower end to the closure 44a. The upper end of conduit 97 is provided with an outwardly extending flange 98 having a recess 99 within which is placed an annular seal 100 which slidably seals conduit member 97 within the inner wall of conduit 90. Aligned with axis 9a and with the opening through cylinder 97 the closure member 11 is provided with an opening 101 which provides access to the interior of cylinder 97. At the lower end of cylinder 97 the closure 44a is provided with an opening 102 through which material may pass through the cylinder 97.

From the foregoing description it is seen that the pistons a and 350 may be extended hydraulically until the outer portion of piston member 250 reaches the upper shoulder of cylinder 19a and the outer part of piston 35a reaches the upper shoulder of square section 50c. The sliding movement of the cylindrical member 41a whose closure 44a is attached to cylindrical member 97, will cause member 97 to slide longitudinally with it. When the lower part of the flange 98 reaches the upper part of flange 94, the continued sliding extension of cylinder 97 will now cause cylinder 90 to slide accordingly. Similarly, retraction of the piston 35a to its position shown in FIG. 4 will cause corresponding retraction of

cylinders

97 and 90 to their positions BhOVWI in FIG. 4. When rotary motion is applied to the cylinders of the pistons by motor 17a, this rotation will be applied through closure 44a to the inner most cylinder 97, and this rotary movement may or may not be transmitted to the cylinder 90 depending on relative amounts of friction at its seals. Relative rotation of the

cylinders

90 and 97 is not required for their operation as their function is the transfer of material through them.

From the foregoing description it is recognized that at any degree of extension or retraction of the pistons and cylinders, material such as fluid may be delivered or recovered through the injection cylinders. This can be useful in applications such as earth drilling where material, ordinarily of a fluid character such as mud or water can be sent either into port 86 or port 101 and recovered through the other port. Normally the delivery will be through the central portion 101 which will deliver the material through opening 102, in which case the recovery will be through port 88 and from where it will flow out through port 86.

FIGS. 1 through 6 show arrangements for injecting material, having a rotational drive capability. It is not essential, however, to provide rotational drive in order to inject or deliver material. FIGS. 7 through 9 show an arrangement for material delivery wherein no rotational drive is provided. The arrangement in FIGS. 7 to 9 is similar to that shown in FIGS. 1 through 3 in that provision is made for material delivery but not for material return or recirculation. It will be understood however that a non-rotational system analogous to that of FIGS. 4 through 6 could be provided wherein there is provision for return or recirculation of the material.

In FIGS. 7 through 9, numerals similar to those used in FIGS. 1 through 3 generally indicate analogous parts excepting that in FIGS. 7 through 9 the subscript b is generally provided. The arrangement comprises a cylindrical or tubular casing 10b having an upper closure 11b and containing three pistons 25b, 33b and 35b together with their respective double walls 30b and 36b and wall 41b. Ducts 27b and 59b through respective pistons 25b and 33b, provide for boom or shaft extension by use of hydraulic fluid sent into the casing at fitting 52b. Fitting 6lb together with ducts 63b, 65b, 67b and 69b and double wall spaces 64b and 68b serve for retraction in the manner previously explained in connection with FIG. 1. Central conduit 28b fixed to upper closure 1 1b serves for delivery of material injected into the upper end of tube 28b which then is ejected through opening 45b through the lower closure member 44b. O-ring-type guides 107 and 108 set in respective recesses aid in maintaining the position of tubular conduit 28 within cylinder 32b.

From this description it is recognized that the boom arrangement may be extended and retracted as desired and in any position of extension or retraction material injected at the upper end of tube 28b will be ejected out of opening 45b.

The devices according to this invention are capable of innumerable other uses in addition to a drill rig mentioned above as one important use. For example, the extendible rotary boom or shaft may be used as a long distance horizontally positioned drill with which a reservoir of water or other drilling fluid may be used for injection of fluid through the material conduit to the drilling bit. Another use would be as a grinding or milling tool, in which case the shaft members would again be likely to be placed positioned horizontally with provision for injecting lubricant through the material conduit to the working parts. Another use would be to support another more or less similar multi-shaft arrangement, in which case one such device could be pointed upwardly with provision for mounting the second multi-shaft device on the end of the outermost shaft section. Still another use could be as a fire fighting boom in which water is supplied to the injector conduit system and ejected from the boom at some distance from the position of supply. The boom may also be used as a fuel system in which fuel is supplied to the materialconveying conduit and delivered at some distance within the limits of extension of the boom. Still a further use is as a sybronetics positioner.

As used in the specification, the terms such as tubular member or conduit member are used to cover such members whether they be of circular cross-section or square cross-section or some other cross-section, and the expression shaft covers a boom whether rotatable or not, and vice versa.

It will also be understood that any number of telescoping shaft members and any number of telescoping material conveying conduit members may be used, as may be desired, and not merely the particular numbers illustrated in the drawings, which are for illustration rather than for limitation of the invention.

It will be understood that the embodiments of the invention illustrated and described herein are given by way of illustration and not of limitation, and that modifications or equivalents or alternatives within the scope of the invention may suggest themselves to those skilled in the art. Thus although in FIGS. 1 and 7 three piston members are shown and in FIG. 4, two piston members are shown, it will be understood that some other number of piston members may be used without departing from the scope of the invention. Moreover, in a device having two or more separate material conveying con- 9 duits such as represented by FIG. 4, the materials may or may not be different and may or may not all flow in the same direction.

I claim:

1. In an extendible and contractible shaft having a plurality of shaft members having a common longitudinal axis and each, except the outermost shaft member, being telescoped within the one next adjacent,

each telescoped shaft member having a piston slidably sealed to the inner wall of the next adjacent outer shaft member to form a series of tendemarranged sealed pistons,

closure means at the end of said outermost shaft member which the pistons approach when the shaft is contracting,

fluid passageways between adjacent shaft members,

means providing fluid communication between adjacent fluid passageways,

a first port means communicating with one side of said piston seals and a second port means communicating with the opposite side of said piston seals, whereby application of fluid pressure at said first port means extends the length of said shaft and application of fluid pressure at said second port means contracts the length of said shaft,

the improvement comprising:

material conveying conduit means comprising a first material conveying tubular conduit section within said shaft and fixed relative to said outermost shaft member and communicating with the exterior of said shaft through said closure means,

a second material conveying tubular conduit section slidably sealed to said first material conveying conduit section so that the conduit means is thereby extendible; and

opening means at the end of the shaft opposite the closure means providing communication with the conduit means.

2. A shaft according to claim 1 in which the second material conveying conduit section is attached to. one of said pistons.

3. A shaft according to claim 1 in which a third material conveying tubular conduit section is attached to a second of said pistons and is slidably sealed to the second material conveying conduit section, thereby making the conduit means further extendible.

4. A shaft according to claim 1 in which the first material conveying conduit section comprises a tubular member concentric with the longitudinal axis.

5. A shaft according to claim 1 in which the conduit means comprises an annular region between the first and second conduit sections concentric with the axis.

6. A shaft according to claim 5 in which the annular region surrounds said first conduit section.

7. A shaft according to claim 5 in which both of said conduit sections are fixed relative to said outermost shaft member.

8. A shaft according to claim 7 including a conduit member in communication with said first conduit section and attached to one of said pistons.

9. A shaft according to claim 1 which includes means for driving said shaft members in rotation.

10. A shaft according to claim 5 which includes means for driving said shaft members in rotation.

11. In an extendible and contractible shaft having a plurality of shaft members having a common longitudinal axis and each, except the outermost shaft member, being telescoped within the one next adjacent,

each telescoped shaft member having a piston slidably sealed to the inner wall of the next adjacent outer shaft member to form a series of tandemarranged sealed pistons,

fluid passageways between adjacent shaft members,

means providing fluid communication between adjacent fluid passageways,

the improvement comprising:

first materialconveying conduit means comprising a first material conveying tubular conduit section positioned to provide communication from the exterior of said shaft through said closure means to a position within said shaft, and fixed relative to said outermost shaft member,

a second material conveying tubular conduit section movable longitudinally within said first conduit section and attached at its end opposite said closure means to a shaft member other than the outermost shaft member.

12. A shaft according to claim 11 in which said other shaft member is provided at its end opposite said closure means, with a second closure means, said second closure means having an opening which communicates with said second conduit section.

13. A shaft according to claim 12 in which a third material conveying tubular conduit section is positioned between said first and second conduit sections and is slidably related to both said first and second conduit sections.

14. A shaft according to claim 11 which includes a second material conveying conduit means comprising a tubular member providing an annular conduit surrounding said first material conveying conduit means and being fixed to the outermost shaft member, the annular conduit communicating with the exterior of the shaft through the first mentioned closure means, said second closure means being provided with a second opening providing communication with said annular conduit.

15. A shaft according to claim 14 in which a shaft member surrounding said tubular member moves longitudinally relative to said annular conduit to extend the length of said annular conduit.

Claims

1. In an extendible and contractible shaft having a plurality of shaft members having a common longitudinal axis and each, except the outermost shaft member, being telescoped within the one next adjacent, each telescoped shaft member having a piston slidably sealed to the inner wall of the next adjacent outer shaft member to form a series of tendem-arranged sealed pistons, closure means at the end of said outermost shaft member which the pistons approach when the shaft is coNtracting, fluid passageways between adjacent shaft members, means providing fluid communication between adjacent fluid passageways, a first port means communicating with one side of said piston seals and a second port means communicating with the opposite side of said piston seals, whereby application of fluid pressure at said first port means extends the length of said shaft and application of fluid pressure at said second port means contracts the length of said shaft, the improvement comprising: material conveying conduit means comprising a first material conveying tubular conduit section within said shaft and fixed relative to said outermost shaft member and communicating with the exterior of said shaft through said closure means, a second material conveying tubular conduit section slidably sealed to said first material conveying conduit section so that the conduit means is thereby extendible; and opening means at the end of the shaft opposite the closure means providing communication with the conduit means.

2. A shaft according to claim 1 in which the second material conveying conduit section is attached to one of said pistons.

11. In an extendible and contractible shaft having a plurality of shaft members having a common longitudinal axis and each, except the outermost shaft member, being telescoped within the one next adjacent, each telescoped shaft member having a piston slidably sealed to the inner wall of the next adjacent outer shaft member to form a series of tandem-arranged sealed pistons, closure means at the end of said outermost shaft member which the pistons approach when the shaft is contracting, fluid passageways between adjacent shaft members, means providing fluid communication between adjacent fluid passageways, a first port means communicating with one side of said piston seals and a second port means communicating with the opposite side of said piston seals, whereby application of fluid pressure at said first port means extends the length of said shaft and application of fluid pressure at said second port means contracts the length of said shaft, the improvement comprising: first material conveying conduit means comprising a first material conveying tubular conduit section positioned to provide communication from the exterior of said shaft through said closure means to a position within said shaft, and fixed relative to said outermost shaft member, a second material conveying tubular conduit section movable longitudinally within said first conduit section and attached at its end opposite said closure means to a shaft member other than the outermost shaft member.