Information
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Patent Grant
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6184843
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Patent Number
6,184,843
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Date Filed
Thursday, October 7, 199924 years ago
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Date Issued
Tuesday, February 6, 200123 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
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CPC
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US Classifications
Field of Search
US
- 343 702
- 343 785
- 343 872
- 343 878
- 343 880
- 343 883
- 343 890
- 343 891
- 343 892
- 343 901
- 318 85
- 318 588
- 403 320
- 483 1
- 483 27
- 029 741
- 029 835
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International Classifications
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Abstract
Extendable/stowable antenna apparatus includes a molded elongated antenna stem with fixed and free ends. The stem is molded with an outer bearing surface, anti-rotation surfaces extending between the fixed and free ends, and a detent surface including a detent stow slot and a detent extend slot. A molded antenna radome includes an elongated opening molded therein with a mating inner bearing surface and anti-rotation surfaces designed to mate with the outer bearing surface and the anti-rotation surfaces of the stem. The opening slidably engages the stem for sliding movements between a stow position and an extended position at the free end. A spring biased detent mechanism in the opening engages the detent stow slot in the stow position and the detent extend slot in the extended position.
Description
FIELD OF THE INVENTION
This invention relates to antennas using extended and stowed positions.
More particularly, the present invention relates to apparatus for positioning an antenna from a stowed position to an extended position and for maintaining the antenna in either position.
BACKGROUND OF THE INVENTION
This invention applies to antennas using extended and stowed positions or other mechanisms using multiple detent positions. Existing technology incorporates separate bearings into the antenna which include anti-rotation and detent features. However, the addition of the separate bearings between an antenna stem and the antenna results in additional tolerance stackup and assembly difficulties. Because the bearings are separate parts, additional features are required in the antenna to contain the bearings. The tolerance stackups can permit malfunction of the anti-rotation features, poor sliding performance, and poor detenting performance. Further, the separate components and additional assembly steps add substantially to the cost. In addition, because of the separate bearing the antenna cannot physically accommodate a smaller antenna element because the bearing fits inside of the element and, therefore, the bearing size controls the element diameter.
Accordingly it is highly desirable to provide apparatus which overcomes these problems and which is inexpensive and easy to install and use.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring to the drawings:
FIG. 1
is an isometric view of a stem for mounting an antenna or other detent apparatus in accordance with the present invention;
FIG. 2
is an enlarged view of a portion of the stem of
FIG. 1
;
FIG. 3
is an isometric view of one portion of an antenna radome designed to mate with the stem of
FIG. 1
, in accordance with the present invention;
FIG. 4
is a sectional view, illustrating a different detent mechanism mounted in an antenna radome in accordance with the present invention;
FIG. 5
is an enlarged isometric view of a spring detent mechanism used in the antenna radome of
FIG. 4
; and
FIG. 6
is an isometric view of the antenna radome and detent mechanism of
FIG. 4
, portions thereof removed for purposes of illustration.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to the drawings and specifically to
FIGS. 1 and 2
, an elongated stem
10
in accordance with the present invention is illustrated. Stem
10
has a fixed end
11
which is attached to a device, such as a telephone or radio that is designed to incorporate an antenna, or other mechanisms using multiple detent positions. An opposed or free end
12
is spaced from fixed end
11
a distance which the antenna or other mechanism is desired to move. In this specific example, stem
10
is used to slidably mount an antenna which is designed for use with portable electronics equipment, such as a telephone, radio, etc.
Elongated stem
10
includes an outer bearing surface
13
and at least one anti-rotation surface
15
(two are illustrated in this embodiment) extending from adjacent fixed end
11
to adjacent free end
12
. Further, a detent surface
17
is formed in the outer surface of stem
10
. Detent surface
17
includes a detent stow slot
18
formed adjacent fixed end
11
of stem
10
and a detent extend slot
19
formed adjacent free end
12
of stem
10
. In this preferred embodiment, anti-rotation surfaces
15
are slots with a generally triangular (arcuate) cross-section to provide positive anti-rotation, as will be explained in more detail presently. It will be understood, of course, that other anti-rotation surfaces, such as different shaped slots or an oval cross-section for stem
10
, could be used if desired or if more convenient in specific applications. Generally, when dealing with very small diameter parts (e.g. telephone or radio antennas) it is impractical to form them with other than round cross-sections, hence the need for some type of slot-shaped anti-rotation surfaces.
In this preferred embodiment stem
10
is molded from some convenient material, such as a hard plastic or the like, and the outer bearing surface
13
, detent surface
17
, and detent stow and extend slots
18
and
19
are all molded integrally into stem
10
. Also, stem
10
is formed in two axially extending portions (generally two halves) for convenience in molding and the two portions are assembled or “clamshelled” together to provide the structure illustrated.
Turning now to
FIG. 3
, an apparatus carrying bearing
20
is illustrated. In this preferred embodiment, apparatus carrying bearing
20
is molded from some convenient material, such as a hard plastic or the like, and is formed in two axially extending portions (generally two halves) for convenience in molding. Only one of the portions is illustrated in
FIG. 3
for convenience in viewing the various features, but it should be understood that a second portion (which could be a mirror image or could include no features except an inner bearing surface) is assembled or “clamshelled” over the illustrated portion to provide a complete structure. Further, in this preferred embodiment, apparatus carrying bearing
20
is formed as an integral portion of a radome housing an antenna (generally incorporated into the radome). Apparatus carrying bearing
20
includes an inner bearing surface
21
formed to mate with outer bearing surface
13
of stem
10
and slidably engage stem
10
for sliding movements between a stow position adjacent fixed end
11
and an extended position adjacent free end
12
.
Apparatus carrying bearing
20
includes mating anti-rotation surfaces
22
which slidably engage anti-rotation surfaces
15
in stem
10
, in the assembled orientation. The combination of anti-rotation surfaces
15
on stem
10
and mating anti-rotation surfaces
22
on apparatus carrying bearing
22
provide positive anti-rotation performance. A detent mechanism
25
is formed on apparatus carrying bearing
20
and includes a detent
26
spring biased against detent surface
17
of stem
10
in the assembled orientation so as to engage detent stow slot
18
when apparatus carrying bearing
20
is slid to the stow position and to engage detent extend slot
19
when apparatus carrying bearing
20
is slid to the extended position. In the embodiment illustrated in
FIG. 3
, detent
26
is positioned on the free end of a cantilever beam
27
which is constructed to provide the spring bias. Further, in this preferred embodiment, inner bearing surface
21
. anti-rotation surfaces
22
, cantilever beam
27
, and detent
26
are molded into apparatus carrying bearing
20
during the molding operation to substantially reduce parts count, assembly operations, tolerance stackup, and costs.
Turning now to
FIG. 4
, another embodiment of extendable/stowable apparatus, designated
30
, is illustrated. In this embodiment, a stem
31
is used which is substantially similar to stem
10
(described above) and, therefore, will not be described further. An apparatus carrying bearing
32
is similar to apparatus carrying bearing
20
except that cantilever beam
27
and detent
26
are replaced with a spring detent mechanism
35
. Referring additionally to
FIG. 5
, it can be seen that spring detent mechanism
35
is formed from a single flat piece of spring metal with a detent
36
formed in the center and downwardly extending legs
37
formed for mounting the structure.
Turning again to
FIG. 4
, it can be seen that a pair of notches
40
are formed in apparatus carrying bearing
32
and receive legs
37
of detent mechanism
35
fixedly therein with detent
36
extending into the central opening defined by the inner bearing surface. As can be seen by referring to both
FIGS. 4 and 6
, detent
36
bears against detent surface
17
of stem
10
in the assembled orientation and is spring biased into engagement with detent stow slot
18
or detent extend slot
19
. Bearing
32
is again fabricated in two axially extending portions, which allows for the easy assembly of detent mechanism
35
into apparatus carrying bearing
32
. Only one of the portions is illustrated in
FIG. 6
for convenience in viewing the various features but it should be understood that a second portion is assembled or “clamshelled” over the illustrated portion to provide a complete structure. Also, in this preferred embodiment, apparatus carrying bearing
32
is an integral portion of a molded radome incorporating an antenna.
Thus, extendable/stowable apparatus is disclosed which includes detents for providing positive positioning and anti-rotation surfaces for positively preventing relative rotation between the components. In a preferred embodiment, the apparatus carrying bearing is formed as an integral part of the apparatus, which substantially reduces part count, assembly operations, and costs. Also, the invention ensures detenting performance that depends less on tolerances of the other parts for proper action. Further, the reduced tolerance stackup by eliminating the separate bearing, results in more reliable sliding performance and more reliable anti-rotation features. In addition, because the separate bearings are eliminated, a smaller diameter and length can be achieved.
While we have shown and described specific embodiments of the present invention, further modifications and improvements will occur to those skilled in the art. We desire it to be understood, therefore, that this invention is not limited to the particular forms shown and we intend in the appended claims to cover all modifications that do not depart from the spirit and scope of this invention.
Claims
- 1. Extendable/stowable apparatus comprising:an elongated stem having a fixed end and an opposed free end, at least one anti-rotation surface on the stem extending from adjacent the fixed end to adjacent the free end; an apparatus carrying bearing slidably engaged on the stem for sliding movements between a stow position at the fixed end and an extended position at the free end, the bearing including a mating anti-rotation surface slidably engaged with the anti-rotation surface on the stem; and a detent surface formed on one of the stem and the bearing and including a detent stow slot and a detent extend slot, and a detent mechanism formed on another of the stem and the bearing and including a detent spring biased against the detent surface so as to engage the detent stow slot when the bearing is slid to the stow position and to engage the detent extend slot when the bearing is slid to the extended position.
- 2. Extendable/stowable apparatus as claimed in claim 1 wherein the detent is formed adjacent a free end of a cantilever beam to provide the spring bias.
- 3. Extendable/stowable apparatus as claimed in claim 1 wherein the detent is attached to a spring mounted on the bearing to provide the spring bias.
- 4. Extendable/stowable apparatus as claimed in claim 1 wherein the bearing defines an elongated opening designed to receive the elongated stem therein.
- 5. Extendable/stowable apparatus as claimed in claim 4 wherein the stem has an outer surface and the at least one anti-rotation surface on the stem is a portion of the outer surface.
- 6. Extendable/stowable apparatus as claimed in claim 5 wherein the at least one anti-rotation surface includes an elongated slot formed in the stem and extending from adjacent the fixed end to adjacent the free end and the mating anti-rotation surface on the bearing includes a projection that extends into and slidably engages the elongated slot.
- 7. Extendable/stowable apparatus as claimed in claim 4 wherein the elongated opening in the bearing defines an inner bearing surface and the stem has an outer surface that defines an outer bearing surface which mates with the inner bearing surface and provides for sliding movements between a stow position at the fixed end and an extended position at the free end.
- 8. Extendable/stowable apparatus as claimed in claim 1 wherein the elongated stem is molded and the bearing is molded into an antenna structure, and the at least one anti-rotation surface, the detent surface, and the detent stow and extend slots are molded into one of the elongated stem and the bearing, and the mating anti-rotation surface and the detent mechanism are molded into the other of the elongated stem and the bearing.
- 9. Extendable/stowable apparatus as claimed in claim 1 wherein the elongated stem is molded and the at least one anti-rotation surface, the detent surface, and the detent stow and extend slots are molded into the elongated stem.
- 10. Extendable/stowable apparatus as claimed in claim 1 wherein the bearing is molded into an antenna structure and the mating anti-rotation surface and the detent mechanism are molded into the antenna structure.
- 11. Extendable/stowable antenna apparatus comprising:an elongated antenna stem having a fixed end and an opposed free end, at least one anti-rotation surface on the antenna stem extending from adjacent the fixed end to adjacent the free end, and a detent surface on the antenna stem including a detent stow slot adjacent the fixed end and a detent extend slot adjacent the free end; and an antenna structure including an antenna carrying bearing formed therein, the antenna carrying bearing being slidably engaged on the antenna stem for sliding movements between a stow position at the fixed end and an extended position at the free end, the bearing including a mating anti-rotation surface slidably engaged with the anti-rotation surface on the antenna stem, and a detent mechanism including a detent spring biased against the detent surface on the antenna stem so as to engage the detent stow slot when the bearing is slid to the stow position and engage the detent extend slot when the bearing is slid to the extended position.
- 12. Extendable/stowable antenna apparatus as claimed in claim 11 wherein the detent mechanism includes a cantilever beam designed to provide the spring bias, the cantilever beam is formed in the antenna structure and includes a detent adjacent an end of the beam.
- 13. Extendable/stowable antenna apparatus as claimed in claim 11 wherein the detent is attached to a spring mounted in the antenna structure to provide the spring bias.
- 14. Extendable/stowable antenna apparatus as claimed in claim 11 wherein the antenna structure includes an elongated opening formed therein and designed to define the antenna carrying bearing and slidably receive the elongated antenna stem therein.
- 15. Extendable/stowable antenna apparatus as claimed in claim 14 wherein the antenna structure is formed as a pair of molded components that fit together to define the elongated opening.
- 16. Extendable/stowable antenna apparatus as claimed in claim 14 wherein the antenna stem has an outer surface and the at least one anti-rotation surface on the antenna stem is a portion of the outer surface.
- 17. Extendable/stowable antenna apparatus as claimed in claim 16 wherein the at least one anti-rotation surface includes an elongated slot formed in the antenna stem and extending from adjacent the fixed end to adjacent the free end and the mating anti-rotation surface on the antenna carrying bearing includes a projection formed in the antenna structure that extends into and slidably engages the elongated slot.
- 18. Extendable/stowable antenna apparatus as claimed in claim 14 wherein the elongated opening in the antenna carrying bearing defines an inner bearing surface and the antenna stem has an outer surface that defines an outer bearing surface which mates with the inner bearing surface and provides for sliding movements between a stow position at the fixed end and an extended position at the free end.
- 19. Extendable/stowable antenna apparatus as claimed in claim 11 wherein the elongated antenna stem is molded and the at least one anti-rotation surface, the detent surface, and the detent stow and extend slots are molded into the elongated antenna stem.
- 20. Extendable/stowable antenna apparatus as claimed in claim 11 wherein the antenna carrying bearing is molded into the antenna structure and the mating anti-rotation surface and the detent mechanism are molded into the antenna structure.
- 21. Extendable/stowable antenna apparatus comprising:a molded elongated antenna stem having a fixed end and an opposed free end, the antenna stem being molded with an outer bearing surface and at least one anti-rotation surface molded into the antenna stem and extending from adjacent the fixed end to adjacent the free end, and a detent surface molded into the antenna stem and including a detent stow slot adjacent the fixed end and a detent extend slot adjacent the free end; and a molded antenna radome having an elongated opening molded therein, the elongated opening of the radome being molded with an inner bearing surface designed to mate with the outer bearing surface of the antenna stem, the inner bearing surface of the elongated opening of the radome and the outer bearing surface of the antenna stem being slidably engaged for sliding movements between a stow position at the fixed end of the antenna stem and an extended position at the free end of the antenna stem, a mating anti-rotation surface molded into the elongated opening of the radome and slidably engaged with the anti-rotation surface on the antenna stem, and a detent mechanism positioned in the elongated opening of the radome and including a detent spring biased against the detent surface on the antenna stem so as to engage the detent stow slot when the bearing is slid to the stow position and engage the detent extend slot when the bearing is slid to the extended position.
US Referenced Citations (4)