Anti-vibration bracket for tubular motor
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.
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The present invention relates generally to motorized window coverings.
BACKGROUND OF THE INVENTIONThe 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.
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.
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 INVENTIONAn 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.
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.
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.
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.
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.
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.
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
Referring initially to
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.
“Tubular motor assembly” will often designate hereunder this suspended mass 11.
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.
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.
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.
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.
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.
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.
Now referring to a non-limiting illustrative embodiment in
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.
As shown in
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
In any case, it is to be understood that the embodiment shown in
Now referring to a non-limiting illustrative embodiment in
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.
As shown in
As in the previous embodiment, the elongated springs 135 may be parts of a same solenoid spring.
It will readily be appreciated that the horizontal stiffness of this embodiment is, at least in one direction, is lower than the vertical stiffness.
As shown in
Accordingly, as shown in
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:
-
- Rotation around a vertical axis crossing the horizontal axis of the suspended mass 11,
- Rotation (tilting) around the horizontal axis of the suspended mass 11,
- 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.
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.
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° is even lower than one tenth of the rated torque of the motor.
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.
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
A simpler embodiment derived from
A combination of
In a simpler embodiment derived from
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.”
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.
Type: Application
Filed: Oct 26, 2004
Publication Date: Apr 27, 2006
Applicant:
Inventors: Alexander Habel (Howell, NJ), Daniel Niemirka (Lawrenceville, NJ), Pierre-Emmanuel Cavarec (San Diego, CA), Tim Morrison (Oceanside, CA)
Application Number: 10/973,995
International Classification: A47H 1/10 (20060101);