US3863405A - Self-erecting tube device - Google Patents

Self-erecting tube device Download PDF

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Publication number
US3863405A
US3863405A US43669774A US3863405A US 3863405 A US3863405 A US 3863405A US 43669774 A US43669774 A US 43669774A US 3863405 A US3863405 A US 3863405A
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Prior art keywords
tube
tip
base
nozzle
device
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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Leigh David Leiter
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Ametek Inc
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Ametek Inc
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64GCOSMONAUTICS; VEHICLES OR EQUIPMENT THEREFOR
    • B64G9/00Cosmonautics not otherwise provided for
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00Details of, or arrangements associated with, antennas
    • H01Q1/08Means for collapsing antennas or parts thereof

Abstract

In a self-erecting tube device having a helical axially extending ribbon of spring material with adjacent turns set to coil tightly in overlapping and telescoping engagement and mounted on a base, the tube on erection is guided by one or two converging-diverging nozzles. On erection, the nozzle or nozzles support the erected tube by virtue of having inner diameters equal to the outer diameter of the portion of the erected tube opposite the nozzle in question. In the single nozzle embodiment the base of the tube may be supported by resilient clamping means. The nozzles in one embodiment are on collapsible telescoping mounts for economy of space in storage. For accurate positioning of the tip there is provided a telescopic connection between the tip and the tube with resilient means biasing the tip outwardly. Restraint means connected to the tip and the base limit the extension of the tip to a predetermined distance from the base.

Description

United States Patent [191 Leiter SELF-ERECTING TUBE DEVICE [75] Inventor: Leigh David Leiter, Willow Grove,

[73] Assignee: Ametek, Inc., New York, NY.

[22] Filed: Jan. 25, 1974 [21] Appl. No.1 436,697

Guerster 52/108 X Guerster 52/108 X Primary Examiner-J. Karl Bell Attorney, Agent, or Firm-Smith, Harding, Earley & Follmer [4 Feb. 4, 1975 [57] ABSTRACT In a self-erecting tube device having a helical axially extending ribbon of spring material with adjacent turns set to coil tightly in overlapping and telescoping engagement and mounted on a base, the tube on erection is guided by one or two converging-diverging nozzles. On erection, the nozzle or nozzles support the erected tube by virtue of having inner diameters equal to the outer diameter of the portion of the erected tube opposite the nozzle in question. 1n the single nozzle embodiment the base of thetube may be supported by resilient clamping means. The nozzles in one embodiment are on collapsible telescoping mounts for economy of space in storage. For accurate positioning of the tip there is provided a telescopic connection between the tip and the tube with resilient means biasing the tip outwardly. Restraint means connected to the tip and the base limit the extension of the tip to a predetermined distance from the base.

8 Claims, 15 Drawing Figures SHEET 1 BF 6 PATENTEU 4l975 SHEET U 0F 6 PATENTED FEB SHEET 6 [1F 6 A FIG. /5

1 SELF-ERECTING TUBE DEVICE BRIEF SUMMARY OF THE INVENTION Self-erecting tubes having a helical axially extending ribbon of spring material with adjacent turns set to coil tightly in overlapping and telescoping engagement are well known in prior art as seen in U.S. Pat. No. 3,467,329 dated Sept. 16, 1969 which is incorporated herein by reference. The self-erecting tubes desirably are guided while erecting. Further, guides are relied upon to hold the axis of the tube in a predetermined position when erected. In addition to guiding, it is necessary to support the outer periphery of the tube near its lower end in order to provide resistance to the lateral displacement of the tube as well as resistance to compression of the tube in the direction of its axis. U.S. Pat. No. 3,467,329 discloses a tubular guide which is satisfactory for guiding but cannot be employed to provide the desired resistance to lateral loading since such a guide having sharp internal edges at its ends causes very high stress concentrations in the tube.

In accordance with this invention, excellent guiding and a high degree of resistance to compressive and cantilever loading results from the employment of one or more converging-diverging nozzles. Each nozzle employed has a minimum inner diameter slightly smaller than the outer diameter of the portion of the erected tube adjacent the minimum diameter to provide for a ram fit of the tube in the nozzle. Advantageously, the inner surface of the nozzle will have a hardness greater than that of the tube to prevent snagging of the tube and to provide for repeated operation. Hardened tool steel and hard anodized aluminum are satisfactory. Case hardened steel may be employed.

When a single nozzle is employed, means are provided to clamp the tube in the vicinity of its stored position. The clamp may be, for example, a spring clamp of the type well known for use with such tubes.

The converging-diverging nozzle provides for gripping the tube after it is erected by a narrow band of the nozzle throat providing for accurate gripping at a known point on the erected tube. It eliminates highly undesirable supporting adjacent a sharp edge and results in a good distribution of the load under cantilever loading of the erected tube. It also provides for accurate positioning of the axis of the tube.

To provide for very accurate positioning of a tip on the outer end of the tube at a predetermined distance from the base on which the tube is mounted, the tip is telescopically connected to the tube and biased outwardly by resilient means such as a compression coil spring. A restraint means is connected to the tip and the base to limit the extension of the tip to a predetermined distance from the base which is less than is permitted by the full extension of the tube per se. This, together with the accurate positioning of the tube axis discussed above, permits the positioning of the end of the erected tube at a predetermined position in space.

To reduce the required storage volume of the device of the invention the nozzle or nozzles employed may be mounted on supports which collapse towards the structure employed to store the ribbon of spring material forming the tube.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view of a self-erecting tube device in accordance with the invention;

FIG. 2 is an elevational view of the device of FIG. 1 in the erected condition;

FIG. 3 is an elevational view, partially broken away, showing the lower nozzle of the device of FIG. I with the tube in the erected condition;

FIG. 4 is an elevational view, partially broken away, of the upper nozzle of the device of FIG. 1 with the tube in the erected condition;

FIG. 5 is a vertical section, partially broken away, through a screw 60 of the device of FIG. 1;

FIG. 6 is an elevational view, partially broken away, of a cord retaining device in the device of FIG. 1;

FIG. 7 is a view taken on the plane indicated by the line 7--7 of FIG. 6;

FIG. 8 is an elevational view of an alternate device in accordance with the invention;

FIG. 9 is an elevational view, partially broken away, of the device of FIG. 8 in the erected condition;

FIG. 10 is a view, partially broken away, taken on the plane indicated by the line 10-10 in FIG. 8;

FIG. 11 is a view taken on the plane indicated by the line 11-11 in FIG. 8;

FIG. 12 is a view taken on the plane indicated by the line l2l2 in FIG. 8;

FIG. 13 is a vertical section, partially broken away, through an alternative device in accordance with the invention;

FIG. 14 is an elevational view, partially broken away, of the device of FIG. 13 in the erected condition; and

FIG. 15 is an enlarged view of the outer nozzle and its mounting in the device of FIG. 8.

DETAILED DESCRIPTION Referring first to FIG. 1, a self-erecting tube device 2 has a base plate 4 by means of which the device 2 can be clamped, bolted or otherwise secured to, for example, a space vehicle or any other supporting structure. Four spaced rods 6 are threadably secured to plate 4 and locked in position by lock nuts 8. Rods 6 pass through openings 10 in flange 12 of canister 13 and are secured by nuts 14 on opposite sides of flange 12 and by lock nuts 16. Canister 13 has a base 18 provided with tapped openings 19 in which rods 20 are threadably secured. Rods 20 pass through clearance holes 22 in guide member 24. Nuts 26 are tightened up against guide member 24 to hold it tightly against canister base 18. Rods 20 pass through clearance openings 28 in base 30 of a bobbin 32 and are held in position by nuts 34 on opposite sides of base 30 and lock nuts 36.

A flexible restraint cord 44 has a knot tied at one end as indicated at 46 and passes through an opening 48 in base 30 and is wound about bobbin 32. Cord 44 is secured by passing it partway into X slot 52 where it is held by a washer 53 (FIG. 6) which is urged against cord 44 by a compression coil spring 54 which is retained by a headed screw 56 secured in bobbin 32. As shown in FIG. 5, cord 44 passes through a central opening 58 in screw 60 and is knotted at its end 62 so that it cannot pull through opening 58. Screw 60 is threadably secured in rod 64 which has secured therein by a pressed fit a pin 66 (FIG. 1) which abuts against a tube 68 through which rod 64 passes. Tube 68 passes through flaired opening 72 in guide member 24 and opening 74 in canister base 18. A compression coil spring 76 biases tube 68 against pin 66.

A collapsed helical ribbon 78 of spring material with adjacent turns set to coil tightly in overlapping and telescoping engagement of the type disclosed in the previously discussed U.S. Pat. No. 3,467,329 has its erecting end secured to tube 68 by a rivet indicated at 80 and its root end secured to canister 13 by a rivet 81. Tube 68 is held by a pin 84 with a handle portion 86, pin 84 passing through openings in tube 68 indicated generally at 88.

Compression coil spring 76 surrounds rod 64 and extends to abut against nut 64A threadably secured to rod 64 and locked by a lock nut 648. A tip pay-load 90 is secured to rod 64 by a set screw indicated at 92. While the tip pay-load may be for a wide variety of uses, the tip pay-load 90 is illustrated as being an electrostatic sensor which is typical of a class of tip pay-loads employed with self-erecting tubes and hence need not be detailed here.

Base 4 is secured to a housing 100 by means of cap screws 102 which pass through clearance holes 104 in base 4 and are threaded to openings 106 in housing 100.

A converging-diverging nozzle 110 has a tapered outer periphery 112 which is held in engagement with tapered wall 114 of base 4 by means of a clamping ring 116 which is secured by cap screws 118 threaded into base 4.

A converging-diverging nozzle 124 has a tapered outer periphery 126 which is held in tight engagement with tapered wall 128 of housing 100 by a clamping ring 130 which is secured by cap screws 132 to housing 100. A flanged split ring 140 has an opening 142 for accommodating tip pay-load 90 and a periphery 144 which engages the inner periphery 146 of clamping ring 130 to retain split ring 140 in position during the storage condition of the device.

In operation, when pin 84 is pulled releasing tube 68, helical ribbon 78 erects into tube 78A (FIG. 2). At the commencement of erection, as tip pay-load 90 is advanced tip pay-load flange 90A moves split ring 140 away from clamping ring 130 and the ring 140 falls clear of the device in two halves. As tube 78A (FIG. 2) erects it is guided by nozzles 110 and 124 and pulls cord 44 off bobbin 32. Before tube 78A (FIG. 2) is arrested by nozzles 110 and 124, cord 44 is fully extended and prevents any further travel of tip pay-load 90. As tube 78A continues to erect, it causes tube 68 to continue to advance and compress spring 76. Then tube 78A rams into nozzles 110 and 124 because at this juncture the diameters of the tube opposite nozzles 110 and 124 have grown to a greater diameter than the inner diameter of nozzles 110 and 124 respectively (FIGS. 3 and 4). This causes a ram fit of tube 78A within nozzles 110 and 124 in the throat of the converging-diverging surfaces and arrests the further movement of tube 78A as best seen in FIGS. 3 and 4.

The tight holding of tube 78A by nozzles 110 and 124 strongly resists axial compression of tube 78A from its outer end. Further, it greatly increases the resistance of the tube to cantilever loading.

An alternative self-erecting tube device 200 is shown in FIGS. 8 and 9. This is a single-nozzle embodiment and largely employs parts employed in the embodiment of FIG. 1 which are given the same numbers as the identical parts in FIG. 1. In the device 200 helical ribbon 78 is retained within a spring clamp 202 which is secured to canister 13 by rivets 204 and 206, rivet 204 additionally engaging the outer root end of ribbon 78. This clamping arrangement is well known to the art.

For proper nozzle centering, a modified base plate 210 is employed as best seen in FIG. 15. Base plate 210 has tapped openings 212 for the reception of rods 6. It has a tapered opening 214, the center of which is shifted in the direction of rivets 204 and 206 (FIG. 8) in order to shift the center line of nozzle in this direction for the proper accommodation of tube 78A when it erects. With two nozzles and without spring clamp 202 as in the embodiment of FIG. 1 it is possible to align the nozzles with the center line of canister 13. However, when only one nozzle is employed with a spring clamp supporting the erected tube in the canister, it is necessary to align the nozzle with the center line of the erect tube within canister 13 as it is held by the spring clamp in order to maintain the erect tube perpendicular to base plate 210.

A tip pay-load 218 (FIG. 8) has 21 depending hollow member 220 which is secured to rod 64 by set screw 92. Hollow member 220 is centered by a split ring member 224 having a half 226 and a half 228, each half being tethered by a line 230 to clamping ring 116. Split ring 224 has a tapered periphery 232 which engages the inner perihphery 234 of clamping ring 116. Depending member 220 has a flange portion 238 the outer periphery of which is greater than the inner periphery of split ring 224.

The operation of the embodiment of FIG. 8 is the same as the operation of the embodiment of FIG. 1 with the following differences. As the tube 78A extends it is guided only by nozzle 110. At the commencement of erection, flange portion 238 of depending member 220 engages split ring 224 and forces it out of clamping ring 116 to fall clear of tube 78A. The erection of tube 78A is arrested when it rams into nozzle 110 at which point the tube is axially aligned with the portion of the tube remaining within canister 13 and held by spring clamp 202.

A third self-erecting tube device 302 is shown in FIGS. 13 and 14. Device 302 has a collapsed helical ribbon 304 of spring material which is of the same type as spring 78 and which is collapsed into a canister 306 which in turn is mounted in a sleeve 308 with the upper end of canister 306 abutting against a shoulder 310 of sleeve 308. The lower end of canister 306 is retained by a base member 312 which is secured to sleeve 308 by cap screws 314. Sleeve 308 is secured to a base 316 by screws indicated at 318 with base 316 having openings 320 for the reception of machine screws for mounting it to the selected supporting surface.

A rivet 326 connects the inner end of helical ribbon 304 to a tube 328 which in turn is connected to a reduced ring portion 330 of a tip pay-load 332 by a set screw indicated at 334. A rivet 335 connects the outer root end of helical ribbon 304 to canister 306.

The device 302 is provided with a pair of convergingdiverging nozzles 340 and 342. Nozzle 340 is connected as by welding to a stepped ring member 344 which in turn is connected to a cylindrical member 346 by cap screws 348. Ring member 344 has a downwardly extending flange 350 which embraces one end of a compression coil spring 352, the other end of which is received in a circular groove 354 in base 316. Sleeve 346 is connected to a ring member 358 by cap screws 360.

Nozzle 342 is connected by welding to a stepped ring member 362 which in turn is connected by welding to a sleeve 364. Sleeve 364 is connected to a ring member 366 by cap screws 368 and is adapted to be moved into contact with a ring 370 which is secured by cap screws 372 to sleeve 308 as will be shown below.

When the device is in the collapsed position, reduced ring portion 330 fits within nozzle 340 to keep the tip pay-load 332 centered and the device is retained in the collapsed position by means of a retaining pin 376 which has a handle 378 and which passes through an opening 380 in base 316, openings 382 and 384 in tube 328 and opening 386 in base 316.

In operation, when pin 376 is pulled clear of base 316, collapsed helical ribbon 304 commences to erect to form tube 304A moving tip pay-load 332 away from ring member 344 and reduced ring portion 330 out of nozzle 340. Compression coil spring 352 now urges ring member 344 upwardly causing ring member 358 to engage stepped ring member 362 which then causes nozzle 342 to move upwardly along the sleeve 364 and ring 366 until ring 366 contacts ring 370 thereby arresting the upward movement of nozzles 340 and 342. When the outer diameters of the erecting tube 304A opposite nozzles 340 and 342 respectively enlarge to the point where they are greater than the inner diameter of the nozzles respectively, the tube 304A will ram into the nozzles and arrest the upward movement of the tube with the results already described above. This embodiment has the obvious advantage of providing two nozzles while using a minimum of space in storage.

It will be understood that the above described embodiments are by way of illustration and are not intended to be limiting.

I claim:

1. in a self-erecting tube having a helical axially extending ribbon of spring material with adjacent turns set to coil tightly in overlapping and telescoping engagement and mounted on a base,

a converging-diverging nozzle for guiding the tube during erection and tightly engaging the tube on full erection, and

a second converging-diverging nozzle spaced from the first mentioned nozzle for guiding the tube during erection and tightly engaging the tube on full erection.

2. The device of claim 1 having collapsible telescoping means for mounting the nozzles.

3. In a self-erecting tube having a helical axially extending ribbon of spring material with adjacent turns set to coil tightly in overlapping and telescoping en gagement and mounted on a base,

a converging-diverging nozzle for guiding the tube during erection and tightly engaging the tube on full erection, and

collapsible telescoping means for mounting the nozzle.

4. In a self-erecting tube having a helical axially extending ribbon of spring material with adjacent turns set to coil tightly in overlapping and telescoping engagement and mounted on a base,

a converging-diverging nozzle for guiding the tube during erection and tightly engaging the tube on full erection,

a tip telescopically connected to the tube,

resilient means biasing the tip outwardly, and

restraint means connected to the tip and the base to limit the extension of the tip to a predetermined distance from the base.

5. A device in accordance with claim 4 in which the resilient means is a spring.

6. A device in accordance with claim 4 in which the tube has a sleeve in its outer end telescopically engaging the tip.

7. A device in accordance with claim 4 in which the tube has a sleeve in its outer end telescopically engaging the tip and the resilient means is a spring engaged between the sleeve and the tip.

8. A device in accordance with claim 7 in which the restraint means is a line.

Claims (8)

1. In a self-erecting tube having a helical axially extending ribbon of spring material with adjacent turns set to coil tightly in overlapping and telescoping engagement and mounted on a base, a converging-diverging nozzle for guiding the tube during erection and tightly engaging the tube on full erection, and a second converging-diverging nozzle spaced from the first mentioned nozzle for guiding the tube during erection and tightly engaging the tube on full erection.
2. The device of claim 1 having collapsible telescoping means for mounting the nozzles.
3. In a self-erecting tube having a helical axially extending ribbon of spring material with adjacent turns set to coil tightly in overlapping and telescoping engagement and mounted on a base, a converging-diverging nozzle for guiding the tube during erection and tightly engaging the tube on full erection, and collapsible telescoping means for mounting the nozzle.
4. In a self-erecting tube having a helical axially extending ribbon of spring material with adjacent turns set to coil tightly in overlapping and telescoping engagement and mounted on a base, a converging-diverging nozzle for guiding the tube during erection and tightly engaging the tube on full erection, a tip telescopically connected to the tube, resilient means biasing the tip outwardly, and restraint means connected to the tip and the base to limit the extension of the tip to a predetermined distance from the base.
5. A device in accordance with claim 4 in which the resilient means is a spring.
6. A device in accordance with claim 4 in which the tube has a sleeve in its outer end telescopically engaging the tip.
7. A device in accordance with claim 4 in which the tube has a sleeve in its outer end telescopically engaging the tip and the resilient means is a spring engaged between the sleeve and the tip.
8. A device in accordance with claim 7 in which the restraint means is a line.
US3863405A 1974-01-25 1974-01-25 Self-erecting tube device Expired - Lifetime US3863405A (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5063969A (en) * 1990-02-27 1991-11-12 Ametek, Inc. Self-erecting spiral metal tube with one textured side
US5433549A (en) * 1993-09-07 1995-07-18 Thomas H. McGaffigan Flexible tie strut
US5667325A (en) * 1995-07-21 1997-09-16 Spar Aerospace Limited Joint for storable tubular extendible member
US5718087A (en) * 1996-05-02 1998-02-17 The Will-Burt Company Telescoping mast assembly
US6054960A (en) * 1997-11-20 2000-04-25 Nec Corporation Retractable antenna for a mobile telephone
US20150323581A1 (en) * 2014-05-08 2015-11-12 The Boeing Company Compact spacecraft antenna field aperture load coupler

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3410615A (en) * 1967-03-31 1968-11-12 Ametek Inc Support bearing for axially movable elongated member having a varying diameter
US3467329A (en) * 1965-10-21 1969-09-16 Ametek Inc Self-erecting spiral tube device
US3679145A (en) * 1970-06-03 1972-07-25 Ametek Inc Device for moving an elongated body in the direction of its axis
US3680802A (en) * 1970-06-03 1972-08-01 Ametek Inc Damped resilient self-erecting means

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3467329A (en) * 1965-10-21 1969-09-16 Ametek Inc Self-erecting spiral tube device
US3410615A (en) * 1967-03-31 1968-11-12 Ametek Inc Support bearing for axially movable elongated member having a varying diameter
US3679145A (en) * 1970-06-03 1972-07-25 Ametek Inc Device for moving an elongated body in the direction of its axis
US3680802A (en) * 1970-06-03 1972-08-01 Ametek Inc Damped resilient self-erecting means

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5063969A (en) * 1990-02-27 1991-11-12 Ametek, Inc. Self-erecting spiral metal tube with one textured side
US5433549A (en) * 1993-09-07 1995-07-18 Thomas H. McGaffigan Flexible tie strut
US5667325A (en) * 1995-07-21 1997-09-16 Spar Aerospace Limited Joint for storable tubular extendible member
US5718087A (en) * 1996-05-02 1998-02-17 The Will-Burt Company Telescoping mast assembly
US6054960A (en) * 1997-11-20 2000-04-25 Nec Corporation Retractable antenna for a mobile telephone
US20150323581A1 (en) * 2014-05-08 2015-11-12 The Boeing Company Compact spacecraft antenna field aperture load coupler
US9470732B2 (en) * 2014-05-08 2016-10-18 The Boeing Company Compact spacecraft antenna field aperture load coupler

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