Abstract:
A pair of foundations held on a central rod disposed along an axis secure a number of connecting rods which, in turn, support portions of a cylinder oriented parallel to the axis. As the angle between the connecting rods and the central rod is adjusted, the cylinder portions move toward and away from the central rod so as to vary the diameter of the adjustable diameter cylindrical mechanism.

Description:
STATEMENT OF RELATED APPLICATIONS 
   This is a continuation-in-part of U.S. patent application Ser. No. 09/645,963, filed Aug. 24, 2000 (now U.S. Pat. No. 6,725,495, issued Apr. 27, 2004) in the name of inventor Masood Habibi, which, in turn, claims the benefit of U.S. Provisional Patent Application Ser. No. 60/150,507, filed Aug. 24, 1999. 

   FIELD OF THE INVENTION 
   The present invention is directed to an adjustable diameter cylindrical mechanism. 
   BACKGROUND OF THE INVENTION 
   Cylindrical hair brushes, curlers and other devices are popularly used for grooming hair. Many different such hairbrushes, curlers, and the like are available having different lengths of bristle and different diameters. Each suits a different purpose. It would be desirable to have a hairbrush capable of adjustment in diameter so that a single hairbrush could be used for a multitude of purposes. Similarly, adjustable diameter curlers would reduce the need for a large collection of fixed-diameter curlers. 
   The present invention addresses this and other problems. These and other features and advantages of the present invention will be presented in more detail in the following specification of the invention and in the associated figures. 
   BRIEF DESCRIPTION OF THE INVENTION 
   A pair of foundations held on a central rod disposed along an axis secure a number of connecting rods which, in turn, support portions of a cylinder oriented parallel to the axis. As the angle between the connecting rods and the central rod is adjusted, the cylinder portions move toward and away from the central rod so as to vary the diameter of the adjustable diameter cylindrical mechanism. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the present description, serve to explain the principles of the invention. 
     In the drawings: 
       FIG. 1  is an end cross-sectional view of an embodiment of the present invention. 
       FIG. 2  is a front perspective view of an embodiment of the present invention. 
       FIG. 3  is a front elevational view of an embodiment of the present invention. 
       FIG. 4  is a front perspective view of an embodiment of the present invention. 
       FIG. 5  is an elevational cross-section of a hair brush in accordance with an embodiment of the present invention. 
       FIG. 6  is an elevational cross-section of a hair brush in accordance with an embodiment of the present invention. 
       FIG. 7  is a cross-sectional view taken along line  7 - 7  of  FIG. 5 . 
       FIG. 8  is a side elevational view of a drive mechanism for an adjustable hair brush in accordance with an embodiment of the present invention. 
       FIG. 9  is a side elevational view of a drive mechanism for an adjustable hair brush in accordance with an embodiment of the present invention. 
       FIGS. 10 and 11  are view of a drive mechanism for an adjustable hair brush in accordance with an embodiment of the present invention. 
       FIG. 12  is a perspective view of a drive mechanism for an adjustable hair brush in accordance with an embodiment of the present invention. 
       FIG. 13  is an elevational view of an outer cylinder portion of an adjustable hair brush in accordance with an embodiment of the present invention. 
   

   DETAILED DESCRIPTION 
   Embodiments of the present invention are described herein in the context of a an adjustable diameter cylindrical mechanism. Some of those embodiments are in the form of an adjustable diameter hairbrush. Those of ordinary skill in the art will realize that the following detailed description of the present invention is illustrative only and is not intended to be in any way limiting. Other embodiments of the present invention will readily suggest themselves to such skilled persons having the benefit of this disclosure. Reference will now be made in detail to implementations of the present invention as illustrated in the accompanying drawings. The same reference indicators will be used throughout the drawings and the following detailed description to refer to the same or like parts. 
   In the interest of clarity, not all of the routine features of the implementations described herein are shown and described. It will, of course, be appreciated that in the development of any such actual implementation, numerous implementation-specific decisions must be made in order to achieve the developer&#39;s specific goals, such as compliance with application- and business-related constraints, and that these specific goals will vary from one implementation to another and from one developer to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of engineering for those of ordinary skill in the art having the benefit of this disclosure. 
   A first implementation of an adjustable diameter cylindrical mechanism in accordance with the teachings of the present invention in the form of an adjustable hair brush as shown in  FIGS. 1-7 . In  FIG. 1  an end cross-sectional view of hair brush  10  is shown. Hair brush  10  includes an inner retaining cylinder  12  to which brush bristles  14  are secured, preferably in clumps of several bristles at each location  16  at which they are secured. An outer cylinder  18  rotates coaxially about the inner retaining cylinder  12  and coaxial with axis  20 . Bristles  14  are directed through apertures  22  in outer cylinder  18 . As relative rotation occurs, the bristles  14  extend from and retract into the brush varying their apparent length and the amount that they protrude from outer cylinder  18 . One or two end caps  24  are preferably affixed to the inner retaining cylinder  12  and incorporate a stop mechanism such as a conventional detent or similar mechanism well known in the art such as a pin  13  moving in a blocked track  15  of end cap  24  to limit rotation beyond a point where the bristles  14  would disengage, i.e., come out of, apertures  22  through which they are to remain threaded. A conventional handle  26  is also provided as shown in  FIG. 4 . Handle  26  may be coupled to inner retaining cylinder  12  so as to provide an easy mechanism for adjustment by rotating handle  26  with respect to end cap  24 . One or two end caps  24  may be provided, as desired. 
     FIGS. 5 and 7  illustrate one version of the hair brush in which pin  13  runs in a blocked track having a clear portion  15  a ( FIG. 7 ) and a blocked portion  15   b . End cap  24   a  may contain blocked track  15  and be coupled to outer cylinder  18 . Handle  26  is coupled to inner cylinder  12 . A ridge  17  holds end  19  of outer cylinder  18  engaged permitting relative rotation of inner retaining cylinder  12  and outer cylinder  18 . 
     FIG. 6  illustrates a slightly different embodiment where handle  26  is used to drive outer cylinder  18  and end cap  24   b  may contain a blocked track mechanism to limit relative rotation of inner retaining cylinder  12  and outer cylinder  18  as before where the end of outer cylinder  18  includes a pin or member  17  moving in an unblocked portion of blocked track  15 . 
   A second implementation of an adjustable hair brush is illustrated in  FIGS. 8-13 . In one specific embodiment the apparatus includes a central rod with a threaded mechanism  39  having a first type of thread (e.g., a right-handed thread) along a first portion  40  thereof and opposite threading (e.g., a left-handed thread) along a second portion  41  thereof. In accordance with this specific embodiment, as the threaded mechanism  39  is rotated (e.g., clockwise), nuts  42  and  43  (if kept from rotating relative to threaded mechanism  39 ) will move apart from one another on the threaded mechanism  39 . As threaded mechanism  39  is rotated in the opposite direction (e.g., counter-clockwise), nuts  42  and  43  (if similarly kept from rotating) will move toward one another. Linkages  44  are all hinged, both to nuts  42  or  43 , as shown, and to outer cylinder portions  45 . Outer cylinder portions  45  include bristles extending therefrom. As nut  42  and nut  43  approach one another, cylinder portions  45  come together, thus reducing the diameter of the hair brush. As nut  42  and nut  43  are moved away from one another, the diameter of the hair brush increases. It should be noted that while the threaded rod and nut mechanism is presently preferred, those of ordinary skill in the art will now realize that other similar mechanisms, such as those involving sliding movement along element  39  could also be used. In such a case element  39  need not be round, nor threaded. 
   In the implementation shown in  FIG. 9 , retaining point  50  may be thought of as fixed. Linkages  51  are hinged to point  50  (which may be implemented as a retaining ring disposed about an axis (such as that parallel to and coaxial with rod  54 ) of the device for constraining the movement of linkages  51  along the axis of the device) and extend therefrom to hingedly engage outer cylinder portions  45  as before. Retaining point  52  is fixed with respect to retaining point  50  along an axis of the device and may also be implemented as a retaining ring disposed about the axis of the device for constraining the movement of linkages  53  along the axis of the device. It is hingedly connected to outer cylinder portions  45  by linkages  53 . As a connecting rod  54 , which is coupled to a pair of drive points  55   a ,  55   b , which are mutually linked, as by a rod, is moved in and out relative to retaining point  50 , linkages  56  which may couple drive point  55   a  and/or drive point  55   b  to linkages  51  and  53 , respectively, in turn cause outer cylinder portions  45  to move in and out in a radial direction with respect to the axis of the device by an action that is similar to the operation of a conventional umbrella. It should be noted that while the threaded rod and nut mechanism is presently preferred in this specific embodiment of the invention as well, those of ordinary skill in the art will now also realize that other similar mechanisms, such as those involving sliding movement along element  54  (as like the mechanism of an umbrella) could also be used. In such a case element  54  need not be round, nor threaded. 
     FIG. 10 . shows outer cylinder portions  45  extended. 
     FIG. 11  shows outer cylinder portions retracted. 
     FIG. 12  shows a front perspective view of the apparatus. 
     FIG. 13  shows how the outer cylinder portions  45  engage one another so that they do not substantially interfere with one another along the path from fully extended to fully retracted, and vice versa. In this case the outer cylinder portions are of two types,  45   a  and  45   b , as shown, are interlock as shown. The outer cylinder portions each comprise a pair of engaging sides  60 . Such engaging side comprises a series of tongues  62  and grooves  64  so that two adjacent engaging side  60  will engage respective tongues  62  with respective grooves  64 . 
   Note that it is also within the scope of this invention to utilize the adjustable hair brush structure as follows: 
   1. for adjustable hair curlers (without the bristles and optionally with hook fasteners of hook and loop type fastening material on the outside of the cylinder to facilitate hair curling) of the heated and unheated types; 
   2. for an attachment to a blow dryer where hot air is blown in along the handle axis (the handle may be deleted in this embodiment and each end cap used to couple to are of the inner and outer cylinders or to the alternative drive mechanism) and out perpendicular to that axis. 
   While embodiments and applications of this invention have been shown and described, it would be apparent to those of ordinary skill in the art having the benefit of this disclosure that many more modifications than mentioned above are possible without departing from the inventive concepts herein. The invention, therefore, is not to be restricted except in the spirit of the appended claims.