Abstract:
Adjustable roller frame includes a pair of housing members having opposed surfaces containing laterally spaced grooves which cooperate to define laterally spaced guideways in which support arms are actually slidably received for supporting roller covers of different lengths and/or diameters between opposite outer end portions of the support arms. These support arms are held in axially adjusted position by one or more cam members movable between a clamping position for applying a friction force to the support arms to hold the support arms against axial movement and a non-clamping position releasing the friction force.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to an adjustable roller frame for supporting roller covers of different lengths and/or diameters. 
       BACKGROUND OF THE INVENTION 
       [0002]    It is generally known to provide adjustable roller frames for supporting roller covers of different lengths and/or diameters, for example, from about 9 inches to about 18 inches in length and from about 1½ inches to about 2¼ inches in diameter. Such roller frames may be used to apply paint or other protective coatings or sealers to relatively large flat surfaces such as floors, walls, ceilings, etc. 
         [0003]    One such adjustable roller frame that provides for the easy removal and replacement of roller covers of different lengths and diameters is disclosed in U.S. Pat. No. 4,868,946 assigned to the same assignee as the present application. The roller frame disclosed in such patent includes a pair of axially slidable support arms that are frictionally held in the desired axially adjusted position between a body member and a clamp member upon tightening fastener means extending through the body member and clamp member between the support arms. The body member and clamp member have opposed recesses or grooves therein which cooperate to define a pair of laterally spaced generally parallel guideways for sliding receipt of the support arms therein. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention relates to an adjustable roller frame that uses one or more cam members to create the friction needed to secure the support arms against axial movement. 
         [0005]    In accordance with one aspect of the invention, the adjustable roller frame comprises a housing including first and second housing members having opposed surfaces containing laterally spaced grooves which cooperate to define a pair of laterally spaced guideways between the housing members in which a pair of support arms are axially slidably received for supporting roller covers of different lengths and/or diameters between opposite outer end portions of the support arms. These support arms are held in axially adjusted position by cam means movable between a clamping position for applying a friction force to the support arms to hold the support arms against axial movement in the guideways and a non-clamping position to release the friction allowing axial movement of the support arms in the guideways. 
         [0006]    In accordance with another aspect of the invention, the cam means may comprise at least one cam pin having one end connected to one of the housing members and another end extending at least partway through the other housing member, and a cam member pivotally connected to the other end of the cam pin, the cam member being engageable with a cam surface on the other housing member during movement of the cam member toward the clamping position to apply a friction force to the support arms. 
         [0007]    In accordance with another aspect of the invention, the one end of the cam pin may be threadedly connected to a nut supported by the one housing member, the nut being rotatable relative to the cam pin to allow for compressive force adjustment of the cam member against the cam surface and field assembly and disassembly of various roller frame parts for cleaning, replacement, and/or repair. 
         [0008]    In accordance with another aspect of the invention, the nut may be fixedly connected to the one housing member. 
         [0009]    In accordance with another aspect of the invention, the opposed surface of each of the housing members may have multiple axially spaced ribs containing the grooves defining the guideways throughout the length of the opposed surface to provide increased surface contact with the support arms, thereby reducing the amount of compressive force of the cam member against the cam surface required to hold the support arms against axial movement when the cam member is in the clamping position. 
         [0010]    In accordance with another aspect of the invention, two axially spaced cam means may be located between the guideways and support arms. 
         [0011]    In accordance with another aspect of the invention, the materials used for the cam means may be non-metallic, eliminating the potential for corrosion. 
         [0012]    These and other aspects, features and advantages of the present invention will become apparent as the following description proceeds. 
         [0013]    To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter more fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail a certain illustrative embodiment of the invention, this being indicative, however, of but several of the various ways in which the principles of the invention may be employed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    The present invention may be more readily understood by reference to the following drawings in which: 
           [0015]      FIG. 1  is a front elevation view of one form of adjustable roller frame according to the present invention; 
           [0016]      FIG. 2  is a top plan view of the roller frame of  FIG. 1 ; 
           [0017]      FIG. 3  is an end elevation view of the roller frame of  FIG. 1  as seen from the right end thereof; 
           [0018]      FIG. 4  is an enlarged longitudinal section through the roller frame housing of  FIG. 2 , taken generally along the plane of the line  4 - 4  thereof; and 
           [0019]      FIG. 5  is an enlarged transverse section through the roller frame housing of  FIG. 2 , taken generally along the plane of the line  5 - 5  thereof. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0020]    Referring now in detail to the drawings, wherein the same reference numbers are used to designate like parts, and initially to  FIGS. 1-3 , there is shown one form of adjustable roller frame  1  of the present invention including a housing  2  comprised of upper and lower housing members  3 ,  4  and one or more associated cam assemblies  5  for supporting a pair of rod-like support arms  8  for axial sliding movement in opposite directions toward and away from each other. Both support arms  8  may be identical so as to be interchangeable, and are generally L-shaped including a short leg  9  and long leg  10 . The short leg  9  may have a relatively flat distal end  11  from which an inwardly facing stub shaft  12  extends for receipt in holes  13  in end caps  14  in the ends of a roller cover  15  shown in phantom lines in  FIGS. 1-3 . 
         [0021]    As best seen in  FIGS. 4 and 5 , housing members  3 ,  4  include opposed surfaces comprised of multiple axially spaced ribs  17 - 22  and  17 ′- 22 ′ each containing two laterally spaced grooves  23 ,  24  and  23 ′,  24 ′ which cooperate to form guideways  25  and  26  therebetween. These guideways have a shape generally corresponding to the cross-sectional shape of non-circular portions  28  of the long legs  10  of support arms  8  to support the support arms against rotation while permitting relative sliding movement of the support arms in opposite directions toward and away from each other for adjusting the longitudinal spacing between the stub shafts  12  for ease of assembly and removal of roller covers  15  of different lengths and/or diameters therebetween. 
         [0022]    The grooves  23 ,  24  and  23 ′,  24 ′ in the ribs  17 - 22  and  17 ′- 22 ′ in the housing members  3 ,  4  are substantially parallel to each other, but the lateral spacing between the rib grooves  23 ′,  24 ′ in lower housing member  4  are somewhat closer together which causes a “towing in” of the short legs  9  of the support arms to bring the stub shafts  12  into substantial coaxial alignment with each other for coaxially supporting a roller cover  15  on the stub shafts as shown in  FIGS. 2 and 3 . 
         [0023]    The maximum and minimum spacing between the opposed flattened ends  11  of support arms  8  will be determined by the overall lengths of the non-circular portions  28  of the long legs  10  thereof as well as the lengths of the upper and lower housing members. Axial inner ends  30  of the non-circular portions  28  of long legs  10  of the support arms act as stops limiting axial inward movement of the support arms relative to housing  2 . End plugs  31  or the like may be pressed into the distal ends  32  of the long legs  10  of support arms  8  to act as stops limiting axial outward movement of the support arms relative to the housing. 
         [0024]    Upper and lower housing members  3 ,  4  and support arms  8  are maintained in the desired assembled relation by one or more cam assemblies  5 . Each cam assembly  5  includes a cam pin member  35  having one end connected to the lower housing member  4  and the other end extending at least partway through the upper housing member  3  and connected to an eccentric cam member  36  as by means of stub shafts  37  extending from one of the members  35 ,  36  into aligned openings  38  in the other member. Extending outwardly from each cam member  36  is a cam lever  39  for ease of pivoting each cam member between the clamping position shown in  FIGS. 4 and 5  in which the cam member  36  engages a cam surface  40  on the upper housing member  3  to apply compressive forces urging the ribs  17 - 22  and  17 ′- 22 ′ on the housing members into frictional engagement with the support arms to hold the support arms in place and a non-clamping position releasing the compressive forces to permit axial movement of the support arms relative to one another. 
         [0025]    Cam pins  35  may be releasably connected to the lower housing member  4  by threadedly connecting the cam pins to nuts  42  fixedly connected to the lower housing member  4 . This allows for adjustment of the compressive force of the cam members  36  acting on the cam surfaces  40  during movement of the cam members to the clamping position by rotating the nuts  42  relative to the cam pins and permits field assembly and disassembly of the roller frame parts for cleaning, replacement and/or repair. 
         [0026]    From the foregoing, it will be apparent that the adjustable roller frame of the present invention is of a unique design that provides for easy removal and replacement of roller covers of different lengths and/or diameters by operation of one or more cam members which cannot easily be taken off and lost or stolen. Yet the nut connections between the cam pins and one of the housing members allow for clamp tension adjustment and field assembly and disassembly of the component parts of the adjustable roller frame for cleaning, replacement and/or repair. 
         [0027]    Moreover, providing multiple axially spaced ribs throughout the length of opposing surfaces of the housing members containing the grooves that cooperate to form the guideways for the support arms increase the surface contact with the support arms, greatly reducing the clamping force required to hold the support arms in proper adjustment. Also, the various components of the adjustable roller frame including particularly the housing, cam pins, cam members and nuts may be made of suitable plastic materials, eliminating the potential for corrosion. 
         [0028]    Although the invention has been shown and described with respect to a certain embodiment, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of the specification. In particular, with regard to the various functions performed by the above-described components, the terms (including any reference to a “means”) used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed component which performs the function of the herein illustrated exemplary embodiment of the invention. In addition, while a particular feature of the invention may have been disclosed with respect to only one embodiment, such feature may be combined with one or more other features as may be desired and advantageous for any given or particular application.