U.S. patent application number 09/825316 was filed with the patent office on 2001-08-02 for portable computer having a sealed hinge clutch.
Invention is credited to Liao, Reynold, O'Neal, Sean P..
Application Number | 20010010621 09/825316 |
Document ID | / |
Family ID | 23520369 |
Filed Date | 2001-08-02 |
United States Patent
Application |
20010010621 |
Kind Code |
A1 |
O'Neal, Sean P. ; et
al. |
August 2, 2001 |
Portable computer having a sealed hinge clutch
Abstract
A portable computer including two plastic enclosures has a first
hinge body attached to a first one of the enclosures. The first
hinge body includes a bore formed therein. A flowable lubricant
such as grease is disposed within the bore. A second hinge body is
attached to a second one of the enclosures. The second hinge body
includes an elongated shaft pivotally mounted within the bore
having grooves formed on an outer surface of the shaft. A sealing
member such as an O-ring is resiliently compressed between one of
the grooves and an inner surface of the bore. A friction member is
seated in another one of the grooves and in contact with the inner
surface of the bore. The seal member has a coefficient of friction
such that friction between the seal member and the bore is
negligible with respect to friction between the friction member and
the bore. The seal member limits the escape of lubricant and the
resulting lubricant-induced stress cracks.
Inventors: |
O'Neal, Sean P.; (Round
Rock, TX) ; Liao, Reynold; (Austin, TX) |
Correspondence
Address: |
David L. McCombs
Haynes and Boone, L.L.P.
600 Congress Avenue, Suite 1600
Austin
TX
78701-3236
US
|
Family ID: |
23520369 |
Appl. No.: |
09/825316 |
Filed: |
April 3, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09825316 |
Apr 3, 2001 |
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09385182 |
Aug 30, 1999 |
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6249426 |
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Current U.S.
Class: |
361/679.27 |
Current CPC
Class: |
Y10T 16/540345 20150115;
G06F 1/1616 20130101; E05Y 2900/606 20130101; Y10S 248/917
20130101; Y10T 29/24 20150115; G06F 1/1681 20130101; Y10T 16/54028
20150115; E05D 11/082 20130101 |
Class at
Publication: |
361/683 |
International
Class: |
G06F 001/16 |
Claims
What is claimed is:
1. A hinge assembly, comprising: a first hinge body including a
bore formed therein; a second hinge body including an elongated
shaft pivotally mounted within the bore; and the shaft having a
plurality of grooves formed therein, at least one of the grooves
having a friction member mounted therein, and another of the
grooves having a resilient seal member mounted therein, the seal
member and the friction member being in friction contact with the
bore, and the seal member having a coefficient of friction such
that friction between the seal member and the bore is negligible
with respect to friction between the friction member and the
bore.
2. The hinge assembly of claim 1 further comprising a lubricant
disposed within the bore of the first hinge body.
3. The hinge assembly of claim 1 wherein the lubricant is
grease.
4. The hinge assembly of claim 1 wherein the lubricant is a
flowable material.
5. The hinge assembly of claim 1 wherein the seal member is an
O-ring.
6. The hinge assembly of claim 1 wherein the grooves are formed on
an outer surface of the shaft.
7. The hinge assembly of claim 1 wherein the first hinge body
includes a tube portion having a closed end and an open end, the
bore extending along a longitudinal axis of the tube portion and
wherein the seal member is positioned adjacent to the open end of
the bore.
8. The hinge assembly of claim 7 wherein the friction member is
positioned between the seal member and the closed end of the tube
portion.
9. The hinge assembly of claim 8 wherein the friction member is
formed of a low carbon steel.
10. A portable computer hinge assembly, comprising: a base; a top
pivotally connected to the base by at least one hinge; a generally
cylindrical tube portion of the hinge, the tube portion having an
open end, a closed end, and an inner surface; a shaft of the hinge
having a first end, a second end and an outer surface, the shaft
being pivotally mounted within the tube, the first end of the shaft
being positioned adjacent to the closed end of the tube and the
second end of the shaft being positioned adjacent to the open end
of the tube; a plurality of grooves formed on an outer surface of
the shaft, at least one of the grooves having a friction member
mounted therein, and another of the grooves having a resilient seal
member mounted therein; and the resilient seal member and the
friction member being in friction contact with the tube, and the
seal member having a coefficient of friction such that friction
between the seal member and the tube is negligible with respect to
friction between the friction member and the tube.
11. A computer system comprising: a chassis including a base and a
top connected to the base by at least one hinge; a microprocessor
mounted in the chassis; an input coupled to provide input into the
microprocessor; a mass storage coupled to the microprocessor; a
display coupled to the microprocessor by a video controller; a
memory coupled to provide storage to facilitate execution of
computer programs by the microprocessor; the hinge including a
first hinge body having a bore formed therein; a second hinge body
including an elongated shaft pivotally mounted in the bore; and the
shaft having a plurality of grooves formed therein, at least one of
the grooves having a friction member mounted therein, and another
of the grooves having a resilient seal member mounted therein, the
seal member and the friction member being in friction contact with
the bore, and the seal member having a coefficient of friction such
that friction between the seal member and the bore is negligible
with respect to friction between the friction member and the
bore.
12. The computer of claim 11 wherein the base and the top are
formed of a polymeric material.
13. The computer of claim 12 further comprising a lubricant
disposed within the bore of the first hinge body.
14. The computer of claim 11 wherein the seal member is an
O-ring.
15. The computer of claim 11 wherein the grooves are formed on an
outer surface of the shaft.
16. The computer of claim 11 wherein the first hinge body member
includes a tube portion having a closed end and an open end, the
bore extending along a longitudinal axis of the tube portion, and
wherein the seal member is positioned adjacent to the open end of
the bore.
17. The computer of claim 16 wherein the friction member is
positioned between the seal member and the closed end of the tube
portion.
18. The computer of claim 17 wherein the friction member is formed
of a low carbon steel.
19. A method of limiting the migration of a lubricant from within a
hinge assembly of a computer, comprising the steps of: forming a
bore in a first hinge body; dispensing a prescribed quantity of the
lubricant into the bore; forming a plurality of grooves on an outer
surface of a shaft of a second hinge body; mounting a seal member
in one of the grooves; mounting a friction member in another one of
the grooves; inserting the shaft into the bore of the second hinge
body whereby the seal member is resiliently compressed between the
groove and an inner surface of the bore; and engaging the seal
member and the friction member in friction contact with the bore,
the seal member having a coefficient of friction such that friction
between the seal member and the bore is negligible with respect to
friction between the friction member and the bore.
20. The method as defined in claim 19 wherein the step of mounting
the friction member includes the step of mounting a plurality of
friction members in a plurality of the grooves.
Description
BACKGROUND
[0001] The disclosures herein relate generally to computer systems
and more particularly to portable computers having a sealed hinge
clutch.
[0002] Portable computers typically include top and base enclosures
formed of synthetic, i.e. plastic material. The top and base of
most portable computers are attached using a metal hinge clutch to
control the torque required to open and close the top. Most
portable computers utilize a hinge clutch having either a friction
plate design or a friction shaft design. The friction shaft design
is often used to minimize the front-to-back dimension of the
portable computer. For this type of design, lubrication is
necessary to maintain a uniform and consistent pivoting action and
clutch torque.
[0003] Various hinge devices have been used in computer housings.
U.S. Pat. No. 5,566,048 discloses a hinge assembly that allows a
display housing to pivot relative to a portable computer base. The
hinge assembly has a pivot shaft attached to the display housing
and a spring. The spring has two ends. One end is attached to the
display housing, and the other end is attached to the base. The
spring counteracts the torque created by the weight of the display
housing. This allows a smaller and lighter friction mechanism to be
used to allow the display housing to remain in an open position at
an angular orientation selected by the user.
[0004] U.S. Pat. No. 5,142,738 discloses a hinge device used
between a rotatable component and a stationary component to work as
a pivoting device. The device provides a restrained rotation of one
component in relation to the other. The rotational restraint is
provided by a high viscosity grease and the torsional force of a
coil spring inserted therein in a predetermined angular range to
restrain the rotating speed by means of the high viscosity grease
and the coil spring.
[0005] U.S. Pat. No. 5,001,659 discloses a structure for connecting
a cover of a portable laptop personal computer, word processor or
similar equipment having a display rotatably connected to a case
which accommodates a body of the computer or word processor. The
case and cover are electrically interconnected at co-active hinge
portions thereof by a pair of deformed O-rings and a pair of flat
O-rings.
[0006] U.S. Pat. No. 4,730,364 discloses a hinge such as may be
used for pivotally attaching a liquid crystal display panel to a
portable computer base. The panel is held open in selected angular
positions by means of a frictional fit between an O-ring and the
end of a bearing which is rotatably retained within a follower, to
compress the O-ring between it and the follower such that the
frictional resistance between the bearing and the follower may be
adjusted to control the holding force on the panel.
[0007] Prior hinge clutches do not incorporate a reliable sealing
mechanism to contain lubricant within the hinge clutch assembly. As
a result, over time, the lubricant has a tendency to migrate from
the metal hinge clutch to the plastic housing. Most of the commonly
used lubricants deteriorate engineering grade plastics commonly
used in computer housings, making them more susceptible to stress
cracks.
[0008] The loss of lubrication also causes the hinge torque to
increase significantly. As the torque required to open and close
the computer enclosure increases, the torque loading applied to the
adjacent portions of the enclosure also increases. The repeated
opening and closing of top of the computer often result in the
formation of stress cracks in deteriorated portions of the plastic
enclosure.
[0009] Accordingly, there is a need for a lubricated hinge clutch
that overcomes the shortcomings of prior hinge clutch assemblies so
as to avoid contaminating the plastic housing.
SUMMARY
[0010] One embodiment, accordingly, provides a hinge clutch having
a seal for containing lubricant therein. To this end, one
embodiment provides a hinge assembly including a first hinge body
having a bore formed therein and a second hinge body including an
elongated shaft pivotally mounted within the bore. The shaft has a
plurality of grooves formed therein. At least one of the grooves
includes a friction member mounted therein and another of the
grooves includes a seal member mounted therein. The seal member and
friction member are in friction contact with the bore. The seal
member has a coefficient of friction such that friction between the
seal member and the bore is negligible with respect to friction
between the friction member and the bore.
[0011] A principal advantage is that the lubricant is sealed and
limited to the metal hinge so that portions of the plastic
enclosure adjacent to the hinge clutch assembly are not exposed to
significant amounts of lubricant, thus reducing the potential for
degradation of the plastic enclosure and the formation of stress
cracks.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0012] FIG. 1 is a perspective view illustrating an embodiment of a
portable computer with the top in a closed position.
[0013] FIG. 2 is a fragmented front view illustrating an embodiment
of a portable computer with the top in an open position.
[0014] FIG. 3 is an exploded view illustrating an embodiment of a
hinge clutch.
[0015] FIG. 4 is a cross sectional view taken along line 4-4 in
FIG. 2.
[0016] FIG. 5 is a block diagram illustrating an embodiment of a
computer system.
DETAILED DESCRIPTION
[0017] An embodiment of a portable computer 10 is illustrated in
FIGS. 1 and 2. The portable computer 10 includes a base 12 and a
top 14. The base 12 and the top 14 are pivotally attached by one or
more hinge clutch assemblies 16, FIGS. 1 and 2. The top 14 is
movable between a closed position C, FIG. 1, and an open position
0, FIG. 2. The base 12 and top 14 may be made from an engineering
grade plastic such as polycarbonate, acrylonitrile butadiene
styrene (commonly known as ABS) or a combination thereof using a
process such as injection molding.
[0018] The hinge clutch assembly 16 provides a resistive torque as
the top 14 of the portable computer 10 is being moved between the
open position O and the closed position C. The resistive torque
provides the operator of the portable computer 10 with resistive
yet smooth feedback while positioning the top 14 in a desired open
position. The hinge clutch assembly 16 also provides suitable
static friction to maintain the top 14 in the desired open
position.
[0019] Referring now to FIGS. 3 and 4, the hinge clutch assembly 16
includes a first hinge body 18 and a second hinge body 20. The
first hinge body 18 includes a mounting flange 22 for attachment to
the base 12 of the portable computer 10. The second hinge body 20
includes a mounting flange 24 for attachment to the top 14 of the
portable computer 10. The orientation of the hinge clutch assembly
16 may be reversed whereby the first hinge body 18 is attached to
the top 14 and the second hinge body 20 is attached to the base 12.
The mounting flanges 22, 24 each include one or more holes 25 for
facilitating attachment of the respective hinge body 18, 20 to the
base 12 or top 14 of the portable computer 10.
[0020] Still referring to FIGS. 3 and 4, the first hinge body 18
includes a tube portion 26 having a closed end 26a adjacent to the
mounting flange 22 and an open end 26b opposite the mounting flange
22. The tube portion 26 has a generally cylindrical interior
surface 30, FIG. 3, defining a bore 27 having a diameter 31. The
second hinge body 20 includes a shaft 32 attached to the mounting
flange 24. The shaft 32 has a diameter 35, FIG. 4, and includes a
plurality of grooves 34. A friction band 36, FIG. 4, is received in
each groove 34. The friction bands 36 are ring-shaped pieces of
wire such as a low carbon steel.
[0021] The difference between the diameter 31 and the diameter 35
defines a friction band gap. The friction bands 36 are sized to
have a diameter that is approximately the same or slightly larger
than the friction band gap. The friction bands are compressed
between the tube portion 26 of the first hinge body 18 and the
shaft 32 of the second hinge body 20. The compression of the
friction bands 36 results in friction when the hinge bodies are
pivoted with respect to each other. The friction provides the
resistive torque applied by the hinge clutch assembly 16 during
movement of the top 14 between the open position O and closed
position C.
[0022] It is desirable for the resistive torque to be maintained at
a relatively constant level over the life of the hinge clutch
assembly 16. Accordingly, a lubricant 38, FIG. 4, such as a
flowable grease composition is disposed between the tube portion 26
of the first hinge body 18 and the shaft 32 of the second hinge
body 20. A suitable lubricant has been found to be a product sold
by the Dow Company under the tradename Molycote. A key aspect of
this invention is to minimize the migration of the lubricant 38
from within the hinge clutch assembly 16. Accordingly, a seal is
formed between the tube portion 26 of the first hinge body 18 and
the shaft 32 of the second hinge body 20. One embodiment for
providing a seal includes forming a groove 40, FIG. 4, on an outer
surface in the shaft 32 adjacent to the flange 24 and compressing a
resilient sealing member 42 between the groove 40 and the interior
surface 30 of the tube portion 26. A suitable resilient sealing
member 42 has been found to be a commercially available O-ring
formed of a material such as silicone rubber using a process such
as injection molding. It is preferred that the O-ring be made of a
material having a low coefficient of friction such that the
friction associated with the O-ring is negligible with respect to
that associated with the friction-rings 36.
[0023] An embodiment of a computer system 50 is illustrated in FIG.
5. The computer system 50 includes at least one microprocessor 52.
The microprocessor 52 is connected to a bus 54. The bus 54 serves
as a connection between the microprocessor 52 and other components
of the computer system 50. One or more input devices 56 may be
coupled to the microprocessor 52 to provide input to the
microprocessor 52. Examples of input devices include keyboards,
touchscreens, and pointing devices such as a mouse, a trackball and
a trackpad. The computer system 50 may also include a display 58
which is coupled to the microprocessor 52 typically by a video
controller 60. Programs and data are stored on a mass storage
device 62 which is coupled to the microprocessor 52. Mass storage
devices include components such as hard disks, optical disks,
magneto-optical drives, floppy drives, and the like. A system
memory 64 provides the microprocessor 52 with fast storage to
facilitate execution of computer programs by the microprocessor 52.
A peripheral device 66 may be connected to the microprocessor 52
for providing the computer system 50 with additional functionality.
Examples of peripheral devices include floppy disk drives, hard
disk drives, compact disc players, digital video disc players,
memory card readers, and other types of devices. The various
components of the computer system are typically mounted in a
chassis or in an enclosure of a desktop or portable computer 10. It
should be understood that other busses and intermediate circuits
can be employed between the components described above and
microprocessor 52 to facilitate interconnection between the
components and the microprocessor 52.
[0024] As it can be seen, the embodiments presented herein provide
several advantages. Only a negligible amount, if any, of the
lubricant can escape from the hinge clutch. The potential for
lubricant-induced stress cracks in a plastic enclosure is reduced.
The modifications to the hinge clutch for implementing a seal do
not necessitate modifications to the enclosure or other portions of
the computer. Furthermore, these modifications do not add
significantly to the cost of the hinge clutch. The addition of the
sealing member does not adversely affect the torque specifications
of the hinge clutch. The torque specification is maintained over a
longer period of time as a result of the volume of lubricant in the
hinge clutch remaining at a relatively constant level.
[0025] Although illustrative embodiments have been shown and
described, a wide range of modification, change and substitution is
contemplated in the foregoing disclosure and in some instances,
some features of the embodiments may be employed without a
corresponding use of other features. Accordingly, it is appropriate
that the appended claims be construed broadly and in a manner
consistent with the scope of the embodiments disclosed herein.
* * * * *