U.S. patent application number 10/973995 was filed with the patent office on 2006-04-27 for anti-vibration bracket for tubular motor.
This patent application is currently assigned to SOMFY SYSTEMS, INC.. Invention is credited to Pierre-Emmanuel Cavarec, Alexander K. Habel, Tim Morrison, Daniel B. Niemirka.
Application Number | 20060086874 10/973995 |
Document ID | / |
Family ID | 35601833 |
Filed Date | 2006-04-27 |
United States Patent
Application |
20060086874 |
Kind Code |
A1 |
Habel; Alexander K. ; et
al. |
April 27, 2006 |
Anti-vibration bracket for tubular motor
Abstract
A bracket includes a rigid member that can be fastened to a
fixture such as a wall, and flexible elements depend downwardly
from the rigid member and are engaged with a tubular motor assembly
of a window covering, awning, projector screen, or the like, to
couple the motor assembly to the fixture while attenuating the
propagation of vibrations from the tubular motor assembly to the
fixture. This reduces noise in the room. The flexible elements may
be flexible strings, elastic strings, or coil springs and have
horizontal stiffness coefficients much lower than the vertical
stiffness coefficient.
Inventors: |
Habel; Alexander K.;
(Howell, NJ) ; Niemirka; Daniel B.;
(Lawrenceville, NJ) ; Cavarec; Pierre-Emmanuel;
(San Diego, CA) ; Morrison; Tim; (Oceanside,
CA) |
Correspondence
Address: |
Ronald R. Santucci
Frommer Lawrence & Haug, LLP
745 Fifth Avenue
NewYork
NY
10151
US
|
Assignee: |
SOMFY SYSTEMS, INC.
|
Family ID: |
35601833 |
Appl. No.: |
10/973995 |
Filed: |
October 26, 2004 |
Current U.S.
Class: |
248/268 |
Current CPC
Class: |
F16F 15/04 20130101;
F16F 1/428 20130101; H02K 5/24 20130101; E06B 9/72 20130101; E06B
9/174 20130101 |
Class at
Publication: |
248/268 |
International
Class: |
A47H 1/10 20060101
A47H001/10 |
Claims
1. An electrical power-drive device comprising: at least one
tubular motor assembly including a rotatable tube holding a motor
therein; and at least one motor bracket coupling the tubular motor
assembly to a fixture, the motor bracket comprising: a rigid member
that can be fastened to a fixture; and plural flexible elements
depending downwardly from the rigid member and coupled to the
tubular motor assembly to couple the tubular motor assembly to the
fixture with a horizontal stiffness lower than a vertical
stiffness.
2. The device of claim 1, wherein the flexible elements are
flexible strings.
3. The device of claim 2, wherein the strings are elastic.
4. The device of claim 1, wherein the flexible elements are
springs.
5. The device of claim 1, wherein the rigid member includes a
horizontal portion defining a top surface, and the flexible
elements extend through respective channels in the horizontal
portion and can rest on the top surface.
6. The device of claim 5, wherein the horizontal portion includes a
rigid horizontal flange and a pad on the flange and defining the
top surface.
7. The device of claim 6, wherein the pad is resilient.
8. The device of claim 5, wherein each flexible element includes a
top stop substantially orthogonal to a long axis of the flexible
element for resting against the top surface of the horizontal
portion of the rigid member.
9. The device of claim 4, wherein the rigid member of the bracket
defines a top surface and the bracket further comprises a
suspension member connected to the tubular motor assembly and
defining a top piece spaced above the top surface of the rigid
member, the springs being disposed between the top piece and the
top surface of the rigid member.
10. The device of claim 1, wherein the tubular motor assembly is
operably engaged with a movable object to move the movable object,
the movable object being selected from the group consisting of
window coverings, solar screens, projection screens, awnings,
roller shutters, roller doors, and roller art work.
11. A powered assembly, comprising: at least one object that can be
moved between an open configuration and a closed configuration; at
least one motor; at least one rotatable tube holding the motor and
coupled to the object to move the object when the motor is
energized; at least one idler bracket engaging the tube with a
fixture for supporting the tube; and at least one motor bracket
coupled to the motor and to the fixture for supporting the tube, at
least the motor bracket including at least one suspension element
substantially dampening noise propagating from the motor toward the
fixture.
12. The powered assembly of claim 11, wherein the motor is powered
by at least one dc battery.
13. The powered assembly of claim 11, wherein the motor bracket
comprises: a rigid member that can be fastened to the fixture; and
plural flexible elements depending downwardly from the rigid member
and coupled to the motor to couple the tube with motor to the
fixture with a horizontal stiffness lower than a vertical
stiffness.
14. The powered assembly of claim 13, wherein the flexible elements
are flexible strings.
15. The powered assembly of claim 14, wherein the strings are
elastic.
16. The powered assembly of claim 13, wherein the flexible elements
are springs.
17. The powered assembly of claim 13, wherein the rigid member
includes a horizontal portion defining a top surface, and the
flexible elements extend through respective channels in the
horizontal portion and can rest on the top surface.
18. The powered assembly of claim 17, wherein the horizontal
portion includes a rigid horizontal flange and a pad on the flange
and defining the top surface.
19. The powered assembly of claim 18, wherein the pad is
resilient.
20. The powered assembly of claim 17, wherein each flexible element
includes a top stop substantially orthogonal to a long axis of the
flexible element for resting against the top surface of the
horizontal portion of the rigid member.
21. The powered assembly of claim 16, wherein the rigid member of
the bracket defines a top surface and the bracket further comprises
a suspension member connected to the motor and defining a top piece
spaced above the top surface of the rigid member, the springs being
disposed between the top piece and the top surface of the rigid
member.
22. The powered assembly of claim 16, wherein the tube is operably
engaged with a movable object to move the movable object, the
movable object being selected from the group consisting of window
coverings, solar screens, projection screens, awnings, roller
shutters, roller doors, and roller art work.
23. The powered assembly of claim 11, wherein the ratio of
horizontal stiffness to vertical stiffness is no more than one
tenth.
24. The device of claim 1, wherein the ratio of horizontal
stiffness to vertical stiffness is no more than one tenth.
25. The powered assembly of claim 13, wherein the flexible element
is established by at least one of: a ribbon, a tape, or a
fabric.
26. The device of claim 1, wherein the flexible element is
established by at least one of: a ribbon, a tape, or a fabric.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to motorized window
coverings.
BACKGROUND OF THE INVENTION
[0002] The present assignee has provided several systems for either
lowering or raising a window covering, or for moving the slats of a
window covering between open and closed positions, under control of
a hand-held remote or other control device. These systems include a
motor that is coupled through gears to the window covering
activation mechanism. When the motor is energized in response to a
user command signal, the activation mechanism moves the window
covering.
[0003] As recognized herein, it is desirable to minimize the noise
emitted by such systems during operations. As further recognized
herein, most of the noise is due to vibrations of the head rail
and/or tube in which the tubular motor is disposed, caused by
vibrations of the motor. The present invention understands that
these vibrations are transmitted to the surface (such as a dwelling
wall) supporting the assembly because the assembly typically is
held to the wall by rigid or at least non-flexible brackets.
[0004] As understood herein, other bracket systems have attempted
to dampen the transmission of vibrations from the motor to the
mounting surface by applying rubber, silicone, urethane or other
soft materials between the rigid bracket and the mounting surface.
One solution that has been advanced is to make the entire bracket
out of a rubber material, but the present invention critically
recognizes that this device is limited by the torque of the system.
Furthermore, during attachment of the bracket to the mounting
surface, the soft material is compressed together, resulting in the
relatively rigid connection sought to be avoided in the first place
and limiting the freedom of movement of the system. With this in
mind, the present invention recognizes the desirability of
dampening noise without unduly limiting the torque of the system,
i.e., to provide a noise dampening system that is substantially
torque independent.
SUMMARY OF THE INVENTION
[0005] An electrical power-drive device includes a tubular motor
assembly including a rotatable tube holding a motor therein. A
motor bracket couples the tubular motor assembly to a fixture. The
motor bracket includes a rigid member that can be fastened to the
fixture, and plural flexible elements depending downwardly from the
rigid member. The flexible elements are coupled to the tubular
motor assembly to couple the tubular motor assembly to the fixture
while attenuating propagation of vibrations from the tubular motor
assembly to the fixture. These flexible elements are arranged in
such a way that the horizontal stiffness is low compared to the
vertical stiffness.
[0006] In a first embodiment, the flexible elements are arranged in
such a way that they work in tension. In a second embodiment, the
flexible elements are arranged in such a way that they work in
compression. Each of first and second embodiments includes several
variants.
[0007] In non-limiting embodiments the flexible elements may be
flexible rubber, urethane, silicone, air or fluid filled rubber,
fabric, rope or plastic strings or they may be metal wires having
motion in at least two degrees of freedom. The strings may be
elastic. The rigid member can include a horizontal portion defining
a top surface, with the flexible elements extending through
respective channels in the horizontal portion and resting on the
top surface. If desired, the horizontal portion can include a rigid
horizontal flange and a resilient pad can be disposed on the flange
to define at least in part the top surface. Each flexible element
may include a top stop that is substantially orthogonal to the long
axis of the flexible element for resting against the top surface of
the horizontal portion of the rigid member.
[0008] Or, the flexible elements can be springs. When springs are
used, the bracket can include a suspension member connected to the
tubular motor assembly and defining a top piece spaced above the
top surface of the rigid member. The springs are disposed between
the top piece and the top surface of the rigid member.
[0009] In another aspect, a powered assembly includes an object
that can be moved between an open configuration and a closed
configuration, a motor, and a rotating tube holding the motor and
coupled to the object to move the object when the motor is
energized. An idler bracket engages the tube with a fixture for
supporting the tube. Also, a motor bracket is coupled to the motor
and to the fixture for supporting the tube. One or both of the
brackets substantially dampen noise propagating from the motor
toward the fixture.
[0010] In yet another aspect, a bracket has a rigid member
connectable to a support surface and at least one flexible element
engaged with the rigid member and coupled to a tubular motor
assembly to suspend the tubular motor assembly from the rigid
member and thereby cause the support surface to support the tubular
motor assembly.
[0011] The details of the present invention, both as to its
construction and operation, can best be understood in reference to
the accompanying drawings, in which like numerals refer to like
parts, and which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a partial cross-sectional view of the present
tubular motor assembly for moving an object such as but not limited
to a window covering, awning, projector screen, and the like,
showing the idler bracket and motor bracket connecting the tubular
motor assembly to a mounting surface;
[0013] FIG. 2 is a schematic end view and front view of a first
variant of the first embodiment of the anti-vibration bracket that
can be used as the motor bracket in FIG. 1, showing coiled wire
rope in tension suspending the motor;
[0014] FIG. 3 is a schematic end view and front view of a first
variant of the second embodiment of the anti-vibration bracket that
can be used as the motor bracket in FIG. 1, showing coiled wire
rope in compression supporting the motor;
[0015] FIG. 4 is a schematic end view of a second variant of the
first embodiment of the anti-vibration bracket that can be used as
the motor bracket in FIG. 1, showing flexible strings in tension
suspended through respective bracket channels to hold the motor, in
a no-torque configuration;
[0016] FIG. 5 is a schematic end view of the second variant of the
first embodiment of the anti-vibration bracket, shown in a
configuration wherein the window covering is extended, producing a
torque;
[0017] FIG. 6 is a schematic end view of a second variant of the
second embodiment of the anti-vibration bracket that can be used as
the motor bracket in FIG. 1, showing springs in compression
suspending the motor;
[0018] FIG. 7 is a schematic end view of a third variant of the
first embodiment of the anti-vibration bracket that can be used as
the motor bracket in FIG. 1, showing strings in tension suspending
the motor;
[0019] FIG. 8 is a schematic end view of a fourth variant of the
first embodiment, showing a tape in tension suspending the motor;
and
[0020] FIG. 9 is a schematic end view of a fifth variant of the
first embodiment, showing two crossed wires in tension suspending
the motor.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] Referring initially to FIG. 1, a motorized covering is
shown, generally designated 10, that includes a rotating tube 12
suspended from which or around which may be wrapped a movable
object 14, such as but not limited to a shade assembly that is
raisable (by rolling up) and lowerable (by rolling down, or
unrolling). The rotating tube 12 rotates by means of an electrical
actuator 20, which preferably is mainly included in the tube. In
that case, a tubular actuator is used.
[0022] The rotating tube 12, the rollable object 14 and the
electrical actuator 20 constitute a suspended mass 11, being a
subset of the window covering, which is suspended by means of two
brackets that will be more described more in detail hereunder.
[0023] "Tubular motor assembly" will often designate hereunder this
suspended mass 11.
[0024] While a roll-up shade is shown, it is to be understood that
the principles herein apply to a wide range of window coverings and
other objects that are to be moved by motors. For example, the
invention applies to raisable and lowerable pleated shades and
cellular shades such as those commonly marketed under the trade
names "Silhouette", "Shangri-La", etc. as well as to projector
screens, security screens, awnings, roller doors, roller art work,
etc. that can be moved by tilting and/or by raising and lowering.
Thus, for example, the rotating tube 12 may be a steel or aluminum
roll-up rod or tube of a shade, awning, or projector screen, or a
tilt rod of a horizontal (or vertical) blind, or other like
operator. It is thus to be further understood that the principles
of the present invention apply to a wide range of window coverings
and other objects including, but not limited to the following:
vertical blinds, fold-up pleated shades, roll-up shades, cellular
shades, skylight covers, etc. Powered versions of such shades are
disclosed in U.S. Pat. No. 6,433,498, incorporated herein by
reference.
[0025] FIG. 1 shows that the electrical actuator 20 can include an
AC induction motor 21, as a single-phase squirrel-cage rotor motor,
which is coupled to a planetary gear train 23. A brake 22 may be
coupled between the electric motor and the gear train to stop the
motor when de-energized. When the motor 21 is energized, its rotor
turns, which turns the gear train 23 that in turn rotates the
output shaft 24, which is coupled to an adapter 29. The adapter 29
is engaged with the inside of the tube 12 so that when the adapter
turns, the tube 12 turns and, hence, the movable object 14, which
is attached to the tube 12, moves, either by raising or lowering or
tilting. The head 26 of the motor housing is held from turning by
the below-described motor bracket.
[0026] To create the appropriate lag in phase between the windings
of the induction motor, a preferably small, lightweight capacitor
25 may be connected to the induction motor 21. To power the
actuator 12, standard power from the public AC power grid 16 may be
used. The tubular actuator may be realized as disclosed in U.S.
Pat. No. 5,105,871-5,220,721-5,429,558-4,720,647, incorporated
herein by reference.
[0027] Alternatively, the electric motor 21 may be a DC motor and
the capacitor 25 is then replaced by a simple rectifier or replaced
by an AC-DC bulk converter if the DC motor is of a low voltage
type.
[0028] It is to be understood that the power supply may be
implemented by means of batteries of rechargeable type or of the
dry type as AA or AAA lithium or alkaline batteries. The batteries
may be located inside or outside the tube 12.
[0029] FIG. 1 also shows that the motorized covering 10 can include
an externally wired IR or RF control signal generator 15 or an
internal RF receiver with electronic control board limit switch
unit 27 included in the actuator 20, for receiving a user command
IR or RF signal. Preferably, the user command signal is generated
by a hand-held user command signal generator 18, which can be an
infrared (IR) remote-control unit or a radio frequency (RF)
remote-control unit, equipped with a user interface as a keypad 19.
Or the user command signal may be generated by any other means of
communication well known in the art, such as by manipulable manual
switches 17. The user command signals can include open, close,
raise, lower, intermediate position and so on.
[0030] The electronic limit circuit board 27 can be electronic or a
mechanical counting limit switch unit which both are disposed
inside the actuator 12. The preferred electronic circuit board 27
includes a microprocessor and/or logic chip for processing the
control signals from the transmitter 18.
[0031] In accordance with present principles, the suspended mass
11, which can be established by a tubular motor assembly in
accordance with the disclosure above, is mounted on a mounting
surface 30 by means of at least one and preferably two noise
dampening brackets that can be identical to each other in
configuration and operation. One bracket is an idler bracket 32 and
engages with the idler end cap 13, while the opposite bracket is a
motor bracket 31. The motor bracket 31 is engaged with the actuator
head 26 that is fixedly engaged with the housing of the actuator 20
to take up, like the idler bracket 32, one-half of the static load
of the actuator 20, of the tube 12 with movable object 14, and
also, unlike the idler bracket 32, to absorb substantially all of
the dynamic load induced by motor torque and/or the static torque
when the window covering is fully extended. A bearing 28 allows the
rotation of the tube 12 relatively to the fixed housing of the
actuator 20. It is to be understood that the mounting surface 30
may be a wall, window jamb, head rail of a window covering, or
other fixture.
[0032] Now referring to a non-limiting illustrative embodiment in
FIG. 2, one exemplary of the first embodiment of the bracket 31 can
be seen. In general, the present bracket may include three basic
components, namely, a flexible component, implemented herein as
plural flexible elements, that couples a rigid member to the motor
assembly, with the rigid member being connected to a support
surface, and a flexible mechanical engagement between the rigid
member and flexible elements to prevent vibration and noise from
being transmitted from the motor assembly to the support surface.
While the motor bracket 31 is shown in FIG. 2, it is to be
understood that the idler bracket 32 may be similarly constructed
if desired.
[0033] The present invention critically recognizes that a
significant increase of efficiency can be realized when the
horizontal stiffness of the mounting system is lower and preferably
much lower than the vertical stiffness. In this way, the present
invention recognizes that the function of hanging the tubular motor
assembly vertically advantageously is separated from the function
of limiting its displacement in the vertical plane. Depending on
the application, the function of limiting displacement in the
vertical plane may be obtained using lateral guides acting on the
fabric of the window covering itself without risking solid-borne
vibration paths. Then, the horizontal stiffness is at least lower
than the vertical stiffness. In non-limiting embodiments the ratio
of horizontal and vertical stiffness is lower than 1 to 10.
[0034] FIG. 2 shows that the bracket 31 may include a rigid member
37 that can be fastened to a fixture such as the mounting surface
30 by, e.g., threaded fasteners, nails, solvent bonding, welding,
soldering, and the like. The non-limiting rigid member 37 may be
made of metal or composite and may be L-shaped as shown, with a
vertical portion 39 that is fastened to the mounting surface 30 and
with a horizontal portion 38.
[0035] As shown in FIG. 2, the horizontal portion 38 of the rigid
member 37 is used to attach the to the top of the flexible
mechanical connection, referred to herein as a "wire rope
isolator", and to suspend the suspended mass 11 from the bottom bar
34, thus putting the wire rope isolator in tension. The wire rope
isolator typically includes a pair of elongated bars, namely, a top
bar 33 and a bottom bar 34, which are connected with each other
through the series of elongated springs 35 distributed
longitudinally along each side of said pair of bars. The bottom bar
34 is attached to another rigid member 36 and may be made of metal
or composite and may be L-shaped as shown where the horizontal
portion attaches to the bottom bar 34 and the vertical portion
attaches to the head 26 of the actuator 20, for respective coupling
of the motor part of the bracket to the structural part of the
bracket. The flexible spring in the form of a wire rope provides
the only physical contact between the vibrating load (the motor and
tube assembly) and the structural part of the bracket, which is
attached to the underlying structure (wall, ceiling, window jamb,
projection screen housing, etc.).
[0036] The elongated springs 35 may be separate but can also be
parts of a same solenoid, a helicoidal spring having its axis
perpendicular to the plane of FIG. 2. In that case, each of the
elongated springs 35 is a portion of half-loop of the solenoid.
[0037] In any case, it is to be understood that the embodiment
shown in FIG. 2 facilitates displacement of the suspended mass 11
in the horizontal direction perpendicular to the plane of FIG. 2,
than it does in the vertical direction, resulting from a lower
stiffness at least in one horizontal direction than in the vertical
direction.
[0038] Now referring to a non-limiting illustrative embodiment in
FIG. 3, an example of a second embodiment of the bracket 31 can be
seen. In order to facilitate the comparison with the first
embodiment shown in FIG. 2, reference numerals of corresponding
parts in FIG. 3 are the same as the corresponding reference
numerals in FIG. 2, preceded by a "one" in the hundreds column.
[0039] A rigid member 137 is shown that can be fastened to a
fixture such as the mounting surface 30 by, e.g., threaded
fasteners, nails, solvent bonding, welding, soldering, and the
like. The non-limiting rigid member 137 may be made of metal or
composite and may be J-shaped as shown, with a horizontal portion
138 that is fastened to the mounting surface 30 and with a vertical
portion 139 and then another horizontal portion 140 of the same
rigid member.
[0040] As shown in FIG. 3, the horizontal portion of the rigid
member 140 is used to attach to the bottom of the flexible
mechanical connection, referred to in FIG. 3 as a "wire rope
isolator", and to support the suspended mass 11 from the top bar
133, thus putting the wire rope isolator in compression. The wire
rope isolator typically includes a pair of elongated bars, namely,
a top bar 133 and a bottom bar 134, which may be connected with
each other through the series of elongated springs 135 distributed
longitudinally along each side of said pair of bars. The top bar
133 is attached to another rigid member 136 and may be made of
metal or composite and may be S-shaped as shown where the top
horizontal portion of the rigid member 136 attaches to the top bar
133 and its vertical portion attaches to the head 26 of the
actuator 20, for respective coupling of the motor part of the
bracket to the structural part of the bracket. The flexible spring
in form of a wire rope provides the only physical contact between
the vibrating load (the motor and tube assembly) and the structural
part of the AVB bracket, which is attached to the underlying
structure (wall, ceiling, window jamb, projection screen housing,
etc.).
[0041] As in the previous embodiment, the elongated springs 135 may
be parts of a same solenoid spring.
[0042] It will readily be appreciated that the horizontal stiffness
of this embodiment is, at least in one direction, is lower than the
vertical stiffness.
[0043] FIG. 4 is a variant of the first embodiment shown in FIG. 2.
FIG. 4 shows that the bracket 31 can include a rigid member 40 that
can be fastened to a fixture such as the mounting surface 30 by,
e.g., threaded fasteners, nails, solvent bonding, welding,
soldering, and the like. The non-limiting rigid member 40 may be
made of metal and may be L-shaped as shown, with a vertical portion
41 that is fastened to the mounting surface 30 and with a
horizontal portion 42 defining a top surface 44. The top surface
may be established by the rigid horizontal flange itself and/or by
a pad 46 that is disposed thereon. The pad 46 may be rubber or
other resilient material.
[0044] As shown in FIG. 4, the horizontal portion of the rigid
member 40 is formed with plural channels 48 that extend completely
vertically through the horizontal portion from top surface to
bottom, and a respective flexible element 50 extends through each
channel 48. The channels can be sized such that the walls of each
channel are slightly spaced from the flexible element 50 as shown.
In the particular embodiment shown in FIGS. 4 and 5, each flexible
element 50 includes a respective disk-shaped top stop 52 that is
substantially orthogonal to the long axis of the flexible element
50 for resting against the top surface 44. The flexible elements 50
may be wire, or rubber or plastic strings, and in addition to being
flexible may be resilient.
[0045] Accordingly, as shown in FIGS. 4 and 5 the flexible elements
50 depend downwardly from the rigid member 40 and are coupled to
the tubular motor assembly, for example to a second rigid member 45
which is itself connected to the head 26 of the actuator 20 by
solvent bonding, fasteners, and the like to couple the tubular
motor assembly to the mounting surface 30 while attenuating
propagation of vibrations from the tubular motor assembly to the
mounting surface. In any case, the flexible elements 50 are
deformable in the two horizontal directions (indicated by arrows
54) and are guided by the channels 48 in the rigid member 40, but
they are not attached to the rigid member 40 and indeed when the
pad 46 is used the flexible elements 50 have no physical contact
with any rigid portion of the bracket 31. Holes 49 may be formed in
the pad 46 to allow a vertical displacement of the flexible
elements 50.
[0046] Assuming that motor bracket 31 and the idle bracket are of
the same type, three degrees of freedom of displacement of the
suspended mass 11 are enabled, at least until contact with other
elements: [0047] Rotation around a vertical axis crossing the
horizontal axis of the suspended mass 11, [0048] Rotation (tilting)
around the horizontal axis of the suspended mass 11, [0049]
Horizontal translation along the axis of the suspended mass 11 or,
equivalently, rotation of the flexible elements 50 around their top
stops 52 in a vertical plane containing the horizontal axis of the
suspended mass.
[0050] For a given angular displacement, each of these rotations
needs a torque to counterbalance the associated stiffness of the
bracket 31. In fact, the bigger the power assembly, the higher the
stiffness that is required, even if the goal is to limit its value.
Then, an implicit relation exists between this stiffness and the
size and mass of the powered assembly. And, as a consequence, such
a relation exists between the above rotations and the rated torque
of the motor.
[0051] In all embodiments of the invention, the torque value that
is needed for an admissible rotation angle is lower or preferably
much lower than the rated torque of the motor. In the preferred
embodiments, the torque giving a rotation of 5.degree. is even
lower than one tenth of the rated torque of the motor.
[0052] In a non-limiting embodiment the inner and outer (relative
to the mounting surface 30) flexible elements 50 are slighting
longer than the more central elements 50, with the center-most
element 50 being shortest of all. Consequently, when the motor is
deenergized, and when the fabric is fully wound around the tube 12,
the top stop 52 of the center-most element 50 contacts the top
surface 44, whereas the top stops 52 of the outer-most elements 50
do not, but rather are spaced above the top surface 44. In that
embodiment, any convex shape of the top stops locus would be
convenient. A parabolic law is a simple way to realize it.
[0053] When the rollable element 14 is at least partially unwound,
the application point of the resulting weight moves in the
direction of arrow 56. Then, the central elastic element is less or
no more stressed, with the next elastic element bearing the weight.
The whole suspended mass 11 rotates, as seen in FIG. 5.
[0054] A simpler embodiment derived from FIG. 4 only contains one
pair of flexible elements. In a low cost realization, they could be
directly fastened to the horizontal portion 42.
[0055] FIG. 6 shows an alternate bracket 60, which is a variant of
the second embodiment, having a rigid member 62 defining a top
surface 64. A metal movable suspension member 66 has bar-like or
chain-like legs 68 connected to a second rigid member 65, which is
connected to the head 26 of the actuator 20. This suspension member
66 includes a top piece 63 that is spaced above the top surface 64
of the rigid member 62. The top piece 63 may be parabolic as shown.
Flexible elements in the form of coil or cylindrical springs 67 are
disposed between the top piece 63 and the top surface 64 of the
rigid member 62 as shown. The legs 68 may be rigid or flexible, and
under no load only the center-most spring 67 need contact the top
piece 63, or all springs 67 can be perpetually connected to both
the top piece 63 and top surface 64. The arrows 69 represent the
allowed tilt of suspended mass 11. If desired, the legs 68 may join
the second rigid member 65 together under the head 26 of the
actuator 20 to cradle the head 26.
[0056] FIG. 7 shows a bracket 70 that is in all essential respects
identical to the bracket 31 shown in FIG. 4, with the following
exceptions. Flexible elements 72 such as wire or other strong
material (or indeed plastic string) are embedded in a resilient top
pad 74 that is on a rigid member 76. The flexible elements 72
extend through respective channels 71 in the rigid member 76 and
connect to the second rigid member 75, which is connected to the
head 26 of the actuator, at the elevational centerline 56 of the
suspended mass 11. In a no torque position, only the central
flexible element 71 bears the weight. As in FIGS. 4 and 5, this
role is shifted when the torque increases.
[0057] FIG. 8 shows a bracket 80 in which the plural flexible
elements are established by a fabric 82. The plural channels of the
previous variants are replaced by one single channel 81. The fabric
may be a cloth ribbon, which can also be rubber impregnated. In
case of low weight of the powered assembly, a simple rubber (or
equivalent) sheet may be used. In any case, the horizontal
stiffness of the twisted sheet preferably should remain low, and
more preferably very low, compared to the vertical stiffness (for
instance a 1/10 ratio). The fabric 82 includes two rigid ends. The
upper end 83 is fixed on the upper surface of a first rigid element
86. Alternatively, it lays upon a pad 84, which is located on the
upper surface. The lower end 87 is secured to a second rigid
element 85. The head 26 of the actuator is connected to the second
rigid element 85.
[0058] FIG. 9 shows a bracket 90 in which the plural flexible
elements are not exactly vertical but instead establish an "X"
pattern between element pairs. The plural channels are replaced by
one single channel 91. It can be appreciated that this embodiment
can be derived from the embodiment of the FIG. 4 by rotating the
suspended mass half a turn in the horizontal plane.
[0059] A combination of FIGS. 8 and 9 would also give another
embodiment that uses a ribbon, which both fabric axes are oriented
at 45.degree. apart from the vertical line.
[0060] In a simpler embodiment derived from FIG. 8 or 9 the channel
is not used and the fabric and/or the elastic elements is/are
directly fastened to the horizontal portion of the first rigid
member (respectively 86, 96).
[0061] While the particular ANTI-VIBRATION BRACKET FOR TUBULAR
MOTOR as herein shown and described in detail is fully capable of
attaining the above-described aspects of the invention, it is to be
understood that it is the presently preferred embodiment of the
present invention and thus, is representative of the subject matter
which is broadly contemplated by the present invention, that the
scope of the present invention fully encompasses other embodiments
which may become obvious to those skilled in the art, and that the
scope of the present invention is accordingly to be limited by
nothing other than the appended claims, in which reference to an
element in the singular is not intended to mean "one and only one"
unless explicitly so stated, but rather "one or more." Moreover, it
is not necessary for a device or method to address each and every
problem sought to be solved by the present invention, for it is to
be encompassed by the present claims. Furthermore, no element,
component, or method step in the present disclosure is intended to
be dedicated to the public regardless of whether the element,
component, or method step is explicitly recited in the claims. No
claim element herein is to be construed under the provisions of 35
U.S.C. section 112, sixth paragraph, unless the element is
expressly recited using the phrase "means for."
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