The present subject matter relates generally to coverings for architectural structures and, more particularly, to a cord drive assembly having a braking member and associated biasing element for use with a covering for an architectural structure, such as a window.
Various operating mechanisms are known that provide a cord drive for raising a covering, such as a Venetian blind or pleated shade, relative to an architectural structure (e.g., a window). Examples of such cord drives are disclosed in U.S. Patent Publication No. 2009/0120592, filed on Nov. 3, 2008, and U.S. Patent Publication No. 2009/0120593, filed on Jan. 16, 2009, the disclosures of both of which are hereby incorporated by reference herein in their entirety for all purposes. In embodiments of the operating mechanisms disclosed in such publications, the cord drive is housed in a plastic housing, and short strokes of a drive cord unwinding from a cord drum raise the covering. Additionally, a spring is used to rewind the cord onto the cord drum after each stroke and a Bendix-type mechanism is used to drive an output shaft in connection with each short cord stroke, with rotation of the output shaft raising the covering. When the cord is released, the drive is disengaged to allow the spring to rewind the drive cord onto the cord drum. Thereafter, when the user again pulls on the drive cord, the Bendix-type mechanism re-engages to rotate the output shaft in a manner that further raises the covering. This process is then repeated until the covering is raised to the desired position.
The Bendix-type mechanism typically includes axially-projecting gear teeth on an input member that is configured to move axially with each drive cord stroke to engage mating axially-projecting gear teeth on an output member of the mechanism in order to drive the output shaft. In addition, the Bendix-type mechanism typically includes a drive member that rotates with the cord spool. The drive member is configured to rotate relative to the input member until an axial projection on the drive member engages an internal face on the input member to rotate the input member and push such member axially to cause the input member to engage with and rotate the output member.
Such a cord drive arrangement requires that there be some amount friction on the input member to prevent rotation of the input member relative to the drive member until the axial projection of the drive member “catches up” to or otherwise engages the internal face on the input member to push it forward and provide the typical Bendix-type mechanism action. In prior art devices, this friction has been obtained by using a plastic arm on the housing that encases the cord drive. The plastic arm contacts the input member and acts as a spring, applying a small spring force to the input member to create friction between the plastic arm and the input member to prevent the input member from rotating with the drive member when it is not being positively driven by the drive member. Unfortunately, given that the plastic arm is held in a stressed condition for a very long period of time, the plastic material may cold flow over time, thereby reducing the spring force provided by the plastic arm such that the plastic arm no longer prevents the input member from rotating with the drive member when it is not being positively driven by the drive gear.
Accordingly, an improved cord drive assembly that allow for a more constant, reliable restraining or braking force to be applied to the input member of an associated Bendix-type mechanism of the cord drive assembly would be welcomed in the technology.
Aspects and advantages of the present subject matter will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the present subject matter.
In various aspects, the present subject matter is directed to a cord drive assembly for raising a covering relative to an architectural structure, such as a window. In one embodiment, the cord drive assembly includes a housing and at least one cord drive component mounted for rotation within the housing. Additionally, in one embodiment, the cord drive assembly includes a biasing element installed relative to the housing such that the biasing element applies a biasing force against a braking member of the cord drive assembly that biases the braking member against the cord drive component to hinder rotation of the cord drive component relative to a second cord drive component positioned within the housing.
These and other features, aspects and advantages of the present subject matter will become better understood with reference to the following Detailed Description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present subject matter and, together with the description, serve to explain the principles of the present subject matter.
This Brief Description is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Brief Description is not intended to identify key features or essential features of the claimed subject matter, nor is it intended as an aid in determining the scope of the claimed subject matter.
A full and enabling disclosure of the present subject matter, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
In general, the present subject matter is directed to a cord drive assembly for raising a covering relative to an architectural structure, such as a window. In accordance with one aspect of this disclosure, which optionally is separate and independent from other aspects, the functioning and operation of a cord drive assembly is improved without altering (or at least without significantly altering) the structure of the operating elements of the cord drive assembly. Instead, in accordance with such aspect of this disclosure, the functioning and operation of a cord drive system is improved by altering the housing of the operating elements. Such alteration generally is less expensive than an alteration to the operating elements themselves. The alteration preferably results in smoother, consistent, and/or repeatable operation of the cord drive assembly.
In one embodiment, the cord drive assembly includes a housing and at least one cord drive component mounted for rotation within the housing. Additionally, in one embodiment, the cord drive assembly includes a biasing element installed relative to the housing such that the biasing element applies a biasing force against a braking member of the cord drive assembly to bias the braking member against the cord drive component to at least partially hinder rotation of the cord drive component within the housing.
In one embodiment, the biasing element corresponds to a spring provided in operative association with the braking member. For instance, the spring may be installed relative to the housing and/or the braking member such that a first portion of the spring is configured to be engaged against a portion of the braking member while a second portion of the spring is configured to be engaged against a portion of the housing. As such, when installed relative to the housing and the braking member, the spring may be configured to apply a biasing force against the braking member that biases the braking member against the cord drive component.
Additionally, in one embodiment, the braking member corresponds to a cantilevered arm of the housing. For example, the housing may define an opening within which the cantilevered arm extends. In such an embodiment, the biasing element may be configured to apply the biasing force against the cantilevered arm such that a distal or free end of the cantilevered arm is biased into engagement with the cord drive component to at least partially hinder rotation of such component within the housing.
In one embodiment, the cantilevered arm is formed integrally with the housing. For example, the cantilevered arm may be configured to extend lengthwise between its distal or free end and an opposed proximal end. In such an embodiment, the proximal end of the cantilevered arm may be formed integrally with the housing.
Moreover, in one embodiment, the cord drive component corresponds to an input member of a Bendix-type mechanism. For instance, the input member may be configured to be moved axially within the housing relative to a corresponding output member of the Bendix-type mechanism between a disengaged or first position and an engaged or second position. In such an embodiment, the input member may be rotationally decoupled from and spaced apart axially relative to the output member when the input member is moved to its disengaged or first position. Similarly, the input member may be rotationally coupled to and positioned adjacent to the output member when the input member is moved to its engaged or second position. In addition, in such an embodiment, the braking member may be configured to apply a braking or restraining force against the input member to at least partially inhibit or hinder its rotation within the housing.
Further, in one embodiment, the cord drive assembly includes a second cord drive component (e.g., a drive shaft) configured to rotate relative to the input member when the input member is located at its first position. In such an embodiment, a portion of the second cord drive component may be configured to contact a corresponding portion of the input member to push the input member axially relative to the output member from the first position to the second position. In addition, when the input member is located at its first position, the braking member may be configured to at least partially hinder rotation of the input member to allow the second cord drive component to rotate relative to the input member.
It should be appreciated that, although the present subject matter will generally be described herein with reference to applying a braking or restraining force to a rotatable component of a cord drive assembly configured for use with a covering for an architectural structure, the disclosed braking member and associated biasing element may be utilized within any other suitable application in which it is desired to prevent or inhibit rotation of a rotatable component.
It should also be appreciated that the disclosed cord drive assembly may correspond to an improvement over existing cord drive assemblies, particularly cord drive assemblies that utilize a Bendix-type mechanism to allow the cord drive to be engaged and disengaged from the output shaft or other output member of the assembly. For example, in one embodiment, the present subject matter may be utilized in connection with the cord drive assemblies disclosed in U.S. Patent Publication Nos. 2009/0120592 and 2009/0120593 (incorporated by reference herein above) to improve the overall operation of such assemblies by allowing a consistent, reliable braking force to be applied to the input member of the associated Bendix-type mechanism.
Referring now to
Referring now to
As shown in
As particularly shown in
To allow for such axial movement of the input member 150, the cord drive assembly 100 may incorporate aspects or features of a Bendix-type mechanism. For instance, as shown in
It should be appreciated that, in other embodiments, the cord drive assembly 100 may have any other suitable Bendix-type configuration that allows a rotating member or component of the cord drive assembly 100 (e.g., such as the input member 150) to be moved axially relative to a corresponding component of the cord drive assembly 100 (e.g., such as the output member 160) between disengaged and engaged positions, thereby allowing such components to be rotationally decoupled and coupled, respectively, relative to each other.
It should also be appreciated that, given the configuration of the cord drive assembly 100 described above and, absent any restraining force being applied to the input member 150, the input member 150 has a tendency to rotate together with the drive cord spool 130 and the drive shaft 140 when in the disengaged position (e.g., as shown in
As indicated above, to inhibit or prevent premature rotation of the input member 150, the cord drive assembly 100 may include one or more braking members configured to provide a braking or restraining force against the input member 150. Specifically, in several embodiments, the braking member(s) may correspond to one or more cantilevered arms of the housing 110. For instance, as shown in
It should be appreciated that, in one embodiment, a second cantilevered arm 122 (
Additionally, in several embodiments, to ensure that a sufficient restraining force is applied against the input member 150 via the cantilevered arms 120, 122, a biasing element is provided in operative association with each cantilevered arm 120, 122. In general, each biasing element may be configured to apply a biasing force against its corresponding cantilevered arm 120, 122 that biases the radially extending finger 125 of such arm 120, 122 into engagement with the input member 150. As such, even when the cantilevered arms 120, 122 are formed from a material that has a tendency to cold flow over time (e.g., a plastic material), the biasing force provided by the biasing elements may maintain the cantilevered arms 120, 122 frictionally engaged with the input member 150 to properly inhibit or prevent premature rotation of the input member 150.
In several embodiments, each biasing element may correspond to a spring configured to apply a radially inwardly directed biasing force against its corresponding cantilevered arm 120, 122. In such embodiments, the specific spring configuration of the biasing elements used within the disclosed cord drive assembly 100 may vary depending on the configuration of the cantilevered arms 120, 122 and/or the housing 110, itself. Thus, it should be appreciated that various different spring configurations may be utilized within the cord drive assembly 100 without departing from the scope and spirit of the present subject matter.
For example, in the embodiment illustrated in
In one embodiment, the central portion 193 of each biasing element 190 may be configured to engage an outer side or surface 126 of its respective cantilevered arm 120, 122. For instance, as shown in
It should be appreciated that, in several embodiments, the biasing element 190 may be non-planar in its neutral or “at rest” state. For instance, as shown in
It should be appreciated that, when the biasing element corresponds to a spring, the spring may be formed from any suitable material, such as a metal material (e.g., steel and/or any other suitable metal material). Additionally, it should be appreciated that, although a “W-shaped” spring has been shown in the illustrated embodiment, any other suitable spring configuration or shape may be utilized that allows the biasing element to function as described herein. For instance, in an alternative embodiment, the biasing element may correspond to a “U-shaped” spring. As indicated above, the specific shape of any spring(s) used may vary, for example, depending on the configuration of the cantilevered arm(s) 120, 122 and/or the configuration of the housing 110 itself.
It should also be appreciated that, in the illustrated embodiment, a biasing element has been provided in operative association with each cantilevered arm 120, 122. However, in alternative embodiments, a biasing element may only be provided in operative association with one of the cantilevered arms, such as the first cantilevered arm 120 or the second cantilevered arm 122.
Moreover, it should be appreciated that, in alternative embodiments, each biasing element may correspond to any other suitable device, mechanism, material, component, and/or the like that is configured to apply a biasing force against its respective cantilevered arm 120, 122 that biases the arm 120, 122 into engagement with the input member 150 of the cord drive assembly 100. For instance, in another embodiment, each biasing element may be formed from an expandable/compressible or elastic material that, when installed relative to the housing/arm, applies a biasing force against the respective cantilevered arm 120, 122.
In addition, it should be appreciated that, in alternative embodiments, the biasing element may be configured to apply a biasing force against any other suitable braking component(s) or member(s) configured to generally function as described herein (e.g., to restrain or inhibit rotation of the input member 150). For instance,
Moreover, it should be appreciated that, in one embodiment, the biasing element described herein may be configured to apply an adjustable biasing force against the associated braking component(s) or member(s). In such an embodiment, the adjustability of the biasing force may allow the cord drive assembly to be tuned based on the braking requirements for each specific application. For example,
While the foregoing Detailed Description and drawings represent various embodiments, it will be understood that various additions, modifications, and substitutions may be made therein without departing from the spirit and scope of the present subject matter. Each example is provided by way of explanation without intent to limit the broad concepts of the present subject matter. In particular, it will be clear to those skilled in the art that principles of the present disclosure may be embodied in other forms, structures, arrangements, proportions, and with other elements, materials, and components, without departing from the spirit or essential characteristics thereof. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present subject matter covers such modifications and variations as come within the scope of the appended claims and their equivalents. One skilled in the art will appreciate that the disclosure may be used with many modifications of structure, arrangement, proportions, materials, and components and otherwise, used in the practice of the disclosure, which are particularly adapted to specific environments and operative requirements without departing from the principles of the present subject matter. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of elements may be reversed or otherwise varied, the size or dimensions of the elements may be varied. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the present subject matter being indicated by the appended claims, and not limited to the foregoing description.
In the foregoing Detail Description, it will be appreciated that the phrases “at least one”, “one or more”, and “and/or”, as used herein, are open-ended expressions that are both conjunctive and disjunctive in operation. The term “a” or “an” element, as used herein, refers to one or more of that element. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. All directional references (e.g., proximal, distal, upper, lower, upward, downward, left, right, lateral, longitudinal, front, rear, top, bottom, above, below, vertical, horizontal, cross-wise, radial, axial, clockwise, counterclockwise, and/or the like) are only used for identification purposes to aid the reader's understanding of the present subject matter, and/or serve to distinguish regions of the associated elements from one another, and do not limit the associated element, particularly as to the position, orientation, or use of the present subject matter. Connection references (e.g., attached, coupled, connected, joined, secured, mounted and/or the like) are to be construed broadly and may include intermediate members between a collection of elements and relative movement between elements unless otherwise indicated. As such, connection references do not necessarily infer that two elements are directly connected and in fixed relation to each other. Identification references (e.g., primary, secondary, first, second, third, fourth, etc.) are not intended to connote importance or priority, but are used to distinguish one feature from another.
All apparatuses and methods disclosed herein are examples of apparatuses and/or methods implemented in accordance with one or more principles of the present subject matter. These examples are not the only way to implement these principles but are merely examples. Thus, references to elements or structures or features in the drawings must be appreciated as references to examples of embodiments of the present subject matter, and should not be understood as limiting the disclosure to the specific elements, structures, or features illustrated. Other examples of manners of implementing the disclosed principles will occur to a person of ordinary skill in the art upon reading this disclosure.
This written description uses examples to disclose the present subject matter, including the best mode, and also to enable any person skilled in the art to practice the present subject matter, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the present subject matter is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
The following claims are hereby incorporated into this Detailed Description by this reference, with each claim standing on its own as a separate embodiment of the present disclosure. In the claims, the term “comprises/comprising” does not exclude the presence of other elements or steps. Furthermore, although individually listed, a plurality of means, elements or method steps may be implemented by, e.g., a single unit or processor. Additionally, although individual features may be included in different claims, these may possibly advantageously be combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. In addition, singular references do not exclude a plurality. The terms “a”, “an”, “first”, “second”, etc., do not preclude a plurality. Reference signs in the claims are provided merely as a clarifying example and shall not be construed as limiting the scope of the claims in any way.
The present application is based upon and claims priority to and the benefit of the filing date of U.S. Provisional Patent Application Ser. No. 62/277,638, filed on Jan. 12, 2016, and titled “Housing with Cantilevered Plastic Arm and Biasing Spring,” the disclosure of which is hereby incorporated by reference herein in its entirety for all purposes.
Number | Date | Country | |
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62277638 | Jan 2016 | US |