This invention relates generally to the field of building structures and more specifically to architectural coverings.
As the interconnectivity of devices, especially home and office devices, grows, the potential for modular spaces has increased dramatically. Modular spaces may allow an occupant to quickly and effortlessly modify an existing space to the occupant's needs. Thus, a bedroom may be converted to an office, a kitchen may be converted to a gathering room or a bedroom, a gathering or living room may be converted to several bedrooms, et cetera. One of the challenges of modifying spaces is changing and/or subdividing the dimensions of the space while still maintaining the privacy of the space. Some solutions to this problem have included modular walls. However, to date, modular walls are either heavy and require a significant amount of energy to move around and/or store, or lack the privacy most uses require.
Another problem exists with regard to the raising and lowering of the roll-up mechanisms, such as shades, walls, and doors, and associated elements such as lift cords and bottom bars, as are known in the art. Prior art solutions include motor driven systems connected to outside power sources. These systems are powerful enough to simply muscle a cover up and down no matter what the weight of the system and despite the high torque requirements to be overcome. These systems are usually bulky, noisy and expensive. Further, despite the advantages the un-counterbalanced weight of the shade system eventually will wear out these systems and lead to expensive replacement options.
For each particular roll-up system, a certain amount of torque must be applied to raise and lower an element. Thus, each system has a particular “torque profile”. With powered systems, the prior art solution, again, is simply to apply more than enough power to overcome the torque requirements. Counterbalanced systems are known in the art that attempt to offset at least partially the heavy weight and torque requirements of a roll-up system so that quieter, less expensive battery powered systems are possible. Most of these systems known to the Applicants involve complicated arrangements of springs, gears and transmission systems. In sum, each of the prior art systems attempts to overcome by brute electrical mechanical force the torque profile created by the weight of the hanging element and connected elements of a particular system or to partially compensate for, to counterbalance, the weight by means of complicated spring, gear and transmission systems. Further, prior art spring counterbalance systems generally overcompensate to ensure complete retrieval of an extended element. Importantly, none of the prior art systems known to Applicants enables a user to construct a counterbalance system that approximates the torque profile of any particular shade system without undue overcompensation and that is easy to add to and delete from as circumstances dictate. Thus, there is significant room for improvement to roll-up systems.
Embodiments of a spring-tensioned roll-up wall are described herein that address at least some of the problems described above in the Background. One way the disclosed system addresses such problems is by significantly increasing the precision with which the spring is tensioned in the roll-up wall. Another way the system improves on previous systems is by creating a trough-shaped torque profile for the system centered roughly around zero net torque for a fixed torque applied by a motor.
Various embodiments may include a flexible panel, a roller tube, a drawbar, one or more mounting brackets, a braking mechanism, and a torsion spring. The flexible panel may have a thickness ranging from 0.005 inches to one inch, a panel length ranging from 24 inches to 600 inches, a bottom end, and a top end. The roller tube may be connected to the top end of the flexible panel. The tube may have an outer diameter ranging from half an inch to 25 inches. The panel may roll onto, and off of, the tube. The drawbar may be connected to the bottom end of the panel. The drawbar may have a weight ranging from half a pound to 80 pounds. At least one mounting bracket may be rotatably connected to the tube. The braking mechanism may be connected to the tube and at least one of the one or more mounting brackets. The braking mechanism may prevent rotation of the tube relative to the one or more mounting brackets. The torsion spring may be disposed within the tube and connected directly, indirectly, or both, to the tube and at least one of the mounting brackets. The spring may be pre-torsioned with a number of rotations as the panel is fully rolled onto the tube. The number of rotations may be determined by: one-half the drawbar weight, multiplied by the square root of the sum of: the product of four, the thickness of the panel, and the length of the panel, divided by pi; and the square of the outer diameter of the tube.
Various embodiments may include a flexible panel, a roller tube, one or more mounting brackets, a braking mechanism, and a torsion spring. The flexible panel may include a bottom end and a top end. The roller tube may be connected to the top end, and the panel may roll onto, and off of, the tube. At least one of the mounting brackets may be rotatably connected to the tube. The braking mechanism may be connected to the tube and at least one of the one or more mounting brackets. The braking mechanism may prevent rotation of the tube relative to the mounting brackets. The torsion spring may be disposed within the tube. The torsion spring may include a first end connected directly, indirectly, or both, to the tube. The torsion spring may include a second end connected directly, indirectly, or both, to at least one of the mounting brackets. The spring may be pre-torsioned before the mounting brackets are mounted to a mounting surface. The pre-torsioning may be accomplished by rotating the second end of the spring relative to the first end of the spring in the same direction as the tube rotates to roll the panel off the tube. Such pre-torsioning may give the apparatus a trough-shaped torque profile.
A more particular description of the system summarized above is made below by reference to specific embodiments. Several embodiments are depicted in drawings included with this application, in which:
A detailed description of embodiments of a spring-tensioned roll-up wall is provided below by example and with reference to embodiments in the appended figures. Those of skill in the art will recognize that the features of the apparatus as described by example in the figures below could be arranged and designed in a wide variety of different configurations. Thus, the detailed description and the description of the embodiments in the figures is merely representative of embodiments of the invention, and is not intended to limit the scope of the invention as claimed.
Various embodiments of a spring-tensioned roll-up wall may include a flexible panel, a roller tube, a drawbar, one or more mounting brackets, a braking mechanism, and a torsion spring. The flexible panel may have a thickness ranging from 0.005 inches to one inch, a panel length ranging from 24 inches to 600 inches, a bottom end, and a top end. The roller tube may be connected to the top end of the flexible panel. The tube may have an outer diameter ranging from half an inch to 25 inches. The panel may roll onto, and off of, the tube. The drawbar may be connected to the bottom end of the panel. The drawbar may have a weight ranging from half a pound to 80 pounds. At least one mounting bracket may be rotatably connected to the tube. The braking mechanism may be connected to the tube and at least one of the one or more mounting brackets. The braking mechanism may prevent rotation of the tube relative to the one or more mounting brackets. The torsion spring may be disposed within the tube and connected directly, indirectly, or both, to the tube and at least one of the mounting brackets. The spring may be pre-torsioned with a number of rotations as the panel is fully rolled onto the tube. The number of rotations may be determined by: one-half the drawbar weight, multiplied by the square root of the sum of: the product of four, the thickness of the panel, and the length of the panel, divided by pi; and the square of the outer diameter of the tube.
Various embodiments may include a flexible panel, a roller tube, one or more mounting brackets, a braking mechanism, and a torsion spring. The flexible panel may include a bottom end and a top end. The roller tube may be connected to the top end, and the panel may roll onto, and off of, the tube. At least one of the mounting brackets may be rotatably connected to the tube. The braking mechanism may be connected to the tube and at least one of the one or more mounting brackets. The braking mechanism may prevent rotation of the tube relative to the mounting brackets. The torsion spring may be disposed within the tube. The torsion spring may include a first end connected directly, indirectly, or both, to the tube. The torsion spring may include a second end connected directly, indirectly, or both, to at least one of the mounting brackets. The spring may be pre-torsioned before the mounting brackets are mounted to a mounting surface. The pre-torsioning may be accomplished by rotating the second end of the spring relative to the first end of the spring in the same direction as the tube rotates to roll the panel off the tube. Such pre-torsioning may give the apparatus a trough-shaped torque profile.
Although principally described herein as a wall for dividing modular spaces, the system may more generally be understood as a roll-up architectural feature. The feature may form a wall, a door, and/or a shade. The door may, for example, be a garage door. The shade may be a window shade. Those of skill in the art recognize the structure claimed herein may be utilized in a variety of other ways.
The roll-up wall may be used in a modular space to adjust the dimensions of the space and/or to subdivide the space. The roller wall may be fixedly and/or moveably attached to one or more fixed walls and/or rails within a ceiling. The winding portion, such as the tube, of the roller wall may be disposed behind and/or within a ceiling, and the ceiling may include an opening corresponding to the flexible panel and/or the drawbar. In various embodiments, the roll-up wall may be mounted to any of a variety of surfaces by the mounting brackets. The mounting brackets may comprise a segment extending into the tube and a segment that mounts to the mounting surface. The tube may be rotatably connected to the segment extending into the tube, such as by one or more support rings having one or more bearings disposed between a portion of the ring fixed to the tube and a portion of the ring fixed to the mounting bracket.
The flexible panel may serve any of a variety of purposes, such as providing a visual barrier and/or an acoustic barrier. The material out of which the flexible panel is comprised may be suited for such purposes. For example, in one embodiment, the flexible panel is comprised of mass-loaded vinyl. As described above, the flexible panel may have a variety of thicknesses, which thicknesses may correspond to the desired features of the barrier. The panel thickness may range from 0.005 inches to one inch, from 0.01 inches to half an inch, or from 0.05 inches to 0.25 inches. In an optimal embodiment, the thickness is 0.12 inches. The present inventors have determined that, especially for embodiments including mass-loaded vinyl, the optimal thickness is 0.12 inches. The optimal thickness represents a balance between privacy and energy efficiency. As the thickness increases, the privacy due to sound and light attenuation increases. However, as the thickness increases, the weight also increases, decreasing the energy efficiency. At a certain thickness, the increase in privacy for additional thickness tapers while the energy efficiency decrease continues steadily. For a variety of materials, including mass-loaded vinyl, this thickness is 0.12 inches.
The flexible panel may have a variety of lengths, the length of the panel extending from the top end to the bottom end. The length may range from 24 inches to 600 inches, encompassing a variety of uses such as from covering a window or bar window to extending the entire height of a commercial warehouse/manufacturing facility. Depending on the application, the length may vary from 36 inches to 360 inches, from 48 inches to 240 inches, or from 72 inches to 180 inches. In an optimal embodiment, the panel length is 114 inches. The such an optimal embodiment may include a modular space with 8-foot (96-inch) ceilings. The additional 18 inches allows for the roll-up wall to be housed in the ceiling and to retain a portion of the flexible panel around the tube as the panel fully extends from the ceiling to the floor. This also minimizes the amount of material required.
The tube may be comprised of any of a variety of materials, including aluminum, steel, iron, carbon, carbon fiber, fiberglass, PVC, ABS, and nylon, among others. The tube diameter may be, in various embodiments, dependent on the panel thickness and length. Thus, an optimal tube diameter may correspond to one or more of the optimal panel thickness and the optimal panel length. Accordingly, the tube diameter may range from half an inch to 25 inches, from one inch to 10 inches, from two inches to eight inches, or from three inches to five inches. In an optimal embodiment, the tube diameter is four inches. Similarly, an optimal drawbar weight may correspond with the tube diameter. The drawbar weight may range from half a pound to 80 pounds, from one to 40 pounds, from two to 30 pounds, from five to 25 pounds, or from 10 to 20 pounds. In an optimal embodiment, the drawbar weight is 15 pounds. The drawbar may have a length perpendicular to a length of the flexible panel, and may be connected to the flexible panel bottom end along the drawbar length.
The tube may include a number of inward-protruding teeth that may engage with one or more torque transmissions disposed within the tube. In various embodiments, the teeth may span the entire length of the tube. This may allow for simplified construction by utilizing the same design for the various transmissions and support rings within the tube. This may also allow for more flexible positioning of such elements within the tube, and for on-site, post-assembly shortening of the tube to adapt to various needed sizes. The transmissions may correspond to the spring or one or more motors. The teeth may also engage with one or more internal support rings that allow the tube to rotate about fixed components disposed within the tube, such as components fixed to at least one of the mounting brackets. The number of teeth may range from one tooth to 64 teeth, from one to 32 teeth, from one to 16 teeth, for from one to eight teeth. In an optimal embodiment, the tube includes four teeth. The number of teeth may be optimal in balancing a minimum number of teeth to support the amount of torque exerted on the tube by the spring with using a minimal amount of material and reducing the complexity of constructing the tube. Additionally, the teeth may be evenly spaced within the tube, may have a uniform size, may be unevenly spaced, and/or may have a non-uniform size. For example, the tube may include a groove formed in an exterior surface of the tube. The groove may have a depth such that a tooth is formed protruding into the tube and outlining the groove. The top end of the flexible panel may insert into the groove and directly connect the flexible panel to the tube.
The tube may have a length perpendicular to the flexible panel length. The tube length may range from 32 inches to 320 inches, from 48 inches to 240 inches, from 60 inches to 150 inches, or from 84 inches to 124 inches. In an optimal embodiment related to the other optimal embodiments described above, the tube length is 100.5 inches. The spring may have an un-extended length parallel to the tube length. The un-extended spring length may be less than the tube length. For example, the un-extend spring length may range from 10 inches to 140 inches, from 18 inches to 96 inches, from 24 inches to 60 inches, or from 36 inches to 48 inches. In an optimal embodiment, the un-extended spring length is 25 inches. The spring may have a wire diameter ranging from 0.1 inches to 0.5 inches, from 0.15 inches to 0.4 inches, or from 0.2 inches to 0.3 inches. In an optimal embodiment, the spring has a wire diameter of 0.207 inches. The spring may have an inner diameter ranging from half an inch to five inches, from one inch to four inches, or from two inches to three inches. In an optimal embodiment, the spring inner diameter is 1.75 inches.
The torsion spring may be comprised of any of a variety of materials, such as iron and/or steel. The torsion spring may have a spring constant ranging from 2 in-lb/rad to 5 in-lb/rad. In an optimal embodiment related to the other optimal embodiments described herein, the spring constant is 3.789 in-lb/rad. The torsion spring may be extended from the spring's free-standing equilibrium length as it is disposed within the tube. Because the spring is fixed to the tube and the mounting bracket, as the tube rotates, such as to unroll the flexible panel, the space between adjacent coils of the spring decreases. Accordingly, the spring may be stretched/extended to account for the decreased inter-coil spacing. The pre-stretching of the spring may correspond to the length of the panel. Accordingly, the pre-stretch may range from one inch to 10 inches, from two inches to eight inches, or from four inches to six inches. In an optimal embodiment, the pre-stretch is four inches.
A bar may be disposed within the spring and connected at one end to at least one of the one or more mounting brackets and at the other end to the tube. The spring may be directly connected to the bar. The bar may retain the spring in the extended/stretched state within the tube. The bar may be directly connected at a first end to a spring-tension transmission. The spring-tension transmission may be directly fixed to the tube. For example, the spring-tension transmission may include one or more grooves corresponding to at least one of the inward-protruding teeth of the tube. The spring-tension transmission may have a diameter equal to an inner diameter of the tube. The bar may be rotatably connected to a second spring-tension transmission. The second spring-tension transmission may be directly fixed to the tube, and may be disposed around an element of the mounting bracket extending into the tube and directly connected to the bar. The second spring-tension transmission may have an outer diameter equal to the inner diameter of the tube and an inner diameter equal to an outer diameter of the mounting bracket element. The second spring-tension transmission may include one or more grooves corresponding to at least one of the inward-protruding teeth of the tube.
One or more of the bar, the spring-tension transmissions, and the mounting bracket element may include a groove around the circumference of the component. The groove may accommodate one or more fixing elements, such as set screws, that fix the spring in the extended/stretched state. The fixing elements may also secure the spring in the pre-torsioned state, and may secure the spring as a torsional force is exerted on the spring by the rotating tube.
The spring may be pre-torsioned by torsioning the spring and fixing the spring in the torsioned state within the tube. The number of rotations required to pre-tension the spring may depend on the torque (Twall) exerted on the tube by the wall and connected elements in any particular state of the wall at which the spring may be pre-torsioned (such as fully rolled, or “open,” or fully unrolled, or “closed”) and the torsional spring constant (k) of the spring. The torque may depend on the drawbar weight (z), the thickness of the panel (t), the length of the panel (l), and the outer diameter of the tube (d). The torque may additionally depend on the width (w) and density (ρ) of the panel, and the relative rotational position (θ) of the tube from its initial “closed” position of zero. In embodiments where the spring is pre-torsioned in the open state, the number of rotations (Nrot) may be expressed as
These functions may determine the optimal amount of pre-tensioning for a given spring. Using the variables described above, a precise number of rotations may be selected for any torsion spring and for any wall at any position. This eliminates the guesswork and imprecision described above in the Background.
The roll-up wall may include a motor and transmission assembly. The motor and transmission assembly may rotate the tube and roll the panel onto, and off of, the tube. The motor and transmission assembly may be disposed within the tube. The motor and transmission assembly may include a variety of components, including a state, a transmission, and/or a rotor. The stator may be fixed, directly or indirectly, to at least one of the one more mounting brackets. The transmission may be directly fixed to the tube. In various embodiments, the transmission may have a structure similar to the spring-tension transmissions described above. Accordingly, the transmission may include one or more grooves corresponding to one or more of the inward-protruding teeth of the tube. The transmission may have an outer diameter equal to an inner diameter of the tube. The rotor may rotatably connect the stator and the transmission. A housing may be disposed within the tube that at least partially encloses one or more of the stator and the rotor. The housing may be comprised of aluminum, steel, iron, carbon, carbon fiber, fiberglass, PVC, ABS, nylon, and/or other similar materials. The housing may be directly fixed to the mounting bracket, and the stator may be directly fixed to the housing. Alternatively, the housing and the stator may both be directly fixed to the mounting bracket. The rotor may be rotatably connected directly to the housing, such as by a slip ring disposed between the rotor and the housing. The rotor may be connected to the housing at an end of the housing opposed the mounting bracket.
The amount of torque required by a motor (Tmotor) incorporated into the system may depend on Twall and the torque exerted by the spring (Tspring). Tspring may depend on k, the maximum rotational position (θmax) of the system from zero, θ, and Nrot. Tmotor may be inversely proportional to the sum of Tspring and Twall, such that
and where c is a negative constant.
The spring may be pre-torsioned before mounting the system to a surface or surfaces by rotating the mounting bracket connected to the spring the desired number of rotations and the fixing the mounting brackets to the surface or surfaces. The mounting bracket may be rotated in the same direction as the tube rotates to unroll the panel. Accordingly, as the panel is unrolled from the tube to θ, the tension in the spring may be reduced. At Nrot=2πθ, Tspring may equal zero. This may correspond with a fraction of L of the panel being unrolled from the tube. In general, as the panel is unrolled from the tube, the amount of mass unrolled per rotation decreases exponentially. Accordingly, the increase of Twall slows. However, Tspring continues a linear increase in the opposite direction of Twall.
In a pre-torsioned system as described in the previous paragraph, the amount of current required by the motor may vary to maintain equilibrium between Tmotor, Tspring, and Twall. Given a fixed Tmotor, the roll-up apparatus may have a trough-shaped torque profile, or net torque (Tnet). The spring may traverse its free-standing equilibrium torsional state as the panel is unrolled. Such may occur from one percent to 30 percent of the panel's length, from 10 percent to 40 percent of the panel's length, or from 25 percent to 50 percent of the panel's length. Additionally, the spring may be pre-torsioned as the panel is rolled fully onto the tube to more accurately ensure the trough-shaped torque profile. As implemented, the apparatus may have a a variable Tmotor to flatten the apparatus torque profile such that the torque profile is roughly constant as the panel is unrolled and rolled. The Tmotor profile relative to time may include various discontinuities, such as described in the following paragraph.
Twall and Tspring may be balanced such that a minimal amount of Tmotor is required, thus allowing for a small motor. Such is particularly beneficial in embodiments with large, heavy panels that may typically require a large, powerful motor. Using the formulas above, however, a minimal Tmotor may be calculated. The motor may include a controller and a torque sensor connected to the motor's output or rotor and electrically connected to the controller. The controller may include instructions for receiving a torque measurement (e.g. Tspring and/or Twall) from the torque sensor and adjusting Tmotor proportionally. For example, as the torque measurement decreases, Tmotor may be decreased, and as the torque measurement increases, Tmotor may be increased. The controller may store a desired Tnet, such as Tnet=0. Tmotor may have a lower threshold such that, as Tspring=−Twall, Tmotor is equal to the lower threshold. Tnet may be equal to zero except at a range around Tspring=−Twall, the range equal to a value ranging from the lower threshold to two times the lower threshold. The controller may include instructions for detecting and preventing the motor from over tensioning the spring.
Various embodiments may include torque sensors between the spring and the tube, between the spring and the mounting bracket, between the motor and the tube, or between the tube and the mounting brackets. The torque sensors may be electrically connected to a controller (such as the motor controller described in the previous paragraph), and the controller may store instructions that, when executed, compare the torques and throttle a current delivered to the motor based on a desired Tnet.l The sensors may detect an over tensioned condition in the spring and report that condition to the controller. The controller may include instructions for detecting and preventing the motor from over tensioning the spring.
A support ring may rotatably connect the housing and the tube. The support ring may be rotatably connected directly to the housing and directly fixed to the tube. The support ring may include one or more grooves corresponding to one or more of the inward-protruding teeth of the tube. The support ring may have an outer diameter equal to an inner diameter of the tube and an inner diameter equal to an outer diameter of the housing. One or more bearings may be disposed between the support ring and the motor housing.
The motor and transmission assembly may exert a torque on the tube that is less than a torque required to roll up the panel. The torsion spring may reduce the torque required by the motor, allowing for a smaller, more energy-efficient motor to be used. Because of the weight of the wall, a larger motor might otherwise have to be used that would not fit within the tube. However, the torsion spring allows a smaller motor to be used that fits within the tube. In various embodiments, the motor and transmission assembly may exert a torque on the tube ranging from 5 in-lb to 320 in-lb, from 10 in-lb to 240 in-lb, from 20 in-lb to 100 in-lb, or from 30 in-lb to 60 in-lb. In an optimal embodiment related to other optimal embodiments described herein, the torque is 45 in-lb.
The braking mechanism may be implemented in the motor and/or between the motor and the tube. In some embodiments, the braking mechanism may comprise friction in the motor. In some embodiments, the braking mechanism may comprise a pawl and gear. An electric motor may disengage the pawl from the gear to allow the tube to freely rotate. In some embodiments, the brake comprises a cam and pins that prevent rotation of the cam. The cam may be connected to the rotor and the transmission, and the pins may be disposed between the cam and the motor housing.
A battery may be disposed within the tube. The battery may be electrically coupled to the motor, and may provide power to the motor. In various embodiments, the battery may be disposed within the tube between the motor and the spring. This may allow the motor and the spring to be fixed to opposing mounting brackets so that the spring may reduce the amount of torque required by the motor. The battery may be rotatably connected to the tube such that the tube rotates freely around the battery as the battery remains, relatively, stationary. Due to friction, some oscillation of the battery may be expected, such as a swing of up to 45 degrees. The battery may be rotatably connected to the tube by a support bearing. For example, the battery may be disposed in a bottom-weighted support slip ring that is fixed to the tube and rotatably connected to the battery. The slip ring may have a structure similar to other support rings and transmissions described herein.
Specific embodiments of the roll-up wall and roll-up wall components described generally above are depicted in the appended FIGs. and described below regarding those FIGs.