Abstract:
Lightweight reinforced modular tubes of extruded plastic material are provided for the first stage of a trolley-type carry case, in combination with a locking mechanism, which facilitates effective extension and collapse of a multi-telescopic handle system. The tubes are made of extruded plastic material and include a pair of opposed metal strips having appropriately spaced and dimensioned apertures for reception of spring loaded locking pins of the telescopic system. The metal strips are respectively retained in position by a pair of radially extending elongated flange members which overlap marginal positions of the strips. The tubes and the metal strips can easily and quickly be cut to size to fit any size carry case. While the metal insert strips are preferably made of aluminum, any material stronger than the extruded plastic of the first stage tube can be used, i.e., steel, nylon, PVC, polyethylene, polycarbonate, or the like.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Application No. 61/297,153, filed Jan. 21, 2010, the disclosure of which is incorporated herein by reference and made a part of this application. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to any lightweight reinforced extruded tubing for telescopic handles for trolley-type carry cases, wherein the first stage tube is reinforced by metal strips having apertures which are dimensioned and positioned to receive the spring biased locking pins of a multi-stage locking mechanism. 
         [0004]    2. Description of the Related Art 
         [0005]    Present day tube technology, particularly technology for the first (i.e., lowermost) stage of telescopic handles for carry cases has advanced in several stages. The following is a brief history of the developments of advancements in such tube technology. 
       First Generation 
       [0006]    In general, the strength requirements of the pair of first stage tubular members which form the basis for a telescopic handle have always required a pair of tubes which are of sufficient strength to withstand the forces generally applied to them, not only during the upward and downward telescopic extension and collapsing action, but also while traveling with the carry case, particularly over rough terrain, stairways and the like. Additionally, when the first stage tubes are outside of the case, it is desirable that they match the case. For this reason, particularly for such applications, the outside of the tube was always made of a plastic material which matched the case. 
         [0007]    In the past, the pair of tubular members which formed the first stage of the telescopic mechanisms for such applications were originally comprised of a pair of metal tubes, each tube being surrounded by a plastic extruded polyvinyl chloride (i.e., PVC) tube assembled to the metal tube so as to appear like plastic tubes to match the carry case. The inner metal tube provided the strength for the spring loaded pins that entered the apertures in the metal tube from the telescopic second and third stage handles. In particular, the metal tube was required in order to provide strength for reception of the pins into the apertures from the second and third stage tubes, since a plastic tube with such apertures would normally not have the strength to receive the pins or to support the forces applied thereto during use. Over time, such apertures, if provided in the plastic tube, would become elongated and worn. Furthermore, the metal tubes provided the strength required for traveling with the case; i.e., bending, tension, compression and shock loads. However, the metal tubes added unwanted additional cost and excessive weight to the entire case. 
       Second Generation 
       [0008]    Subsequently an improved version of the first stage tubes was provided by simply individually molding a pair of plastic tubes of ABS (i.e., Acrylonitrile-Butadiene-Styrene) in individual molds. The individually molded tubes were stronger than the extruded tubes of the first generation. However they also needed to be reinforced by a metal tube inserted into the plastic tube as in the first generation. These metal tubes were also capable of carrying the loads from the spring loaded pins provided by the second and third stage telescoping tubes. As in the first generation tubes, the metal tubes also added strength and weight to the tube, and the carry case, as well. 
         [0009]    One disadvantage however, of the molded tubes is that they needed to be custom molded for individually sized carry cases, thus increasing their production costs. For example, each pair of first stage tubes required an individualized molding process for each size carry case. This is in sharp contrast with the prior generation of extruded tubes which were simply cut to size for each style and size of carry case. Accordingly, it would appear that extruded tubes always provided a significant advantage over molded tubes. However, notwithstanding that fact, the present invention can be used with individually molded tubes as well. 
       SUMMARY OF THE INVENTION 
       [0010]    A tube for a first stage of a telescopic handle system for a trolley-type carry case is disclosed, which comprises an elongated tubular member, and at least a pair of opposed radially inwardly extending members extending from the inner surface of the tubular member, each said inwardly extending member being comprised of a radially inwardly extending member having a generally circumferential flange member extending from the free end thereof and each said flange member facing the other so as to form a pair of opposed flange members which define a space therebetween for reception of an elongated reinforcement strip. 
         [0011]    At least one elongated reinforcement strip is positioned between the flange members and retained in position against the inner surface of the elongated tubular member, the elongated reinforcement strip being of a material which adds strength to the elongated tubular member. The elongated reinforcement strip has a plurality of apertures dimensionally and relatively spaced for reception of spring biased locking pins associated with a locking device for retaining respective associated stages of a telescopic handle in either the withdrawn or the extended position when the pins enter predetermined respective apertures in said reinforcement strip. 
         [0012]    The tubular member for the first stage of a telescopic handle assembly for a trolley-type carry case, said generally tubular member is made of an extruded plastic material and defines a generally central elongated tubular opening, the tubular member including within the generally tubular opening, a pair of opposed reinforcement strips extending generally along the length thereof. Each reinforcement strip is retained in position by retaining members positioned therealong and adjacent thereto, the reinforcement strips being of a material of strength generally greater than the strength of the material of the extruded plastic tubular member. Each said reinforcement strip has a plurality of apertures of predetermined size and relative positions for respective reception of spring biased pins associated with respective second and third stage sections of the telescopic handle assembly for respective retention of the handle assembly in the respective collapsed and extended positions. 
         [0013]    The extruded plastic tubular member preferably comprises a plurality of radial plastic ribs extending inwardly of the inner surface to provide structural support to the tubular member. The handle system comprises a pair of said first stage tubular members. 
         [0014]    A locking system is provided to extend and lock second and third stage sections in selected portions. 
         [0015]    The third stage tubes are connected by a gripping handle and the locking system includes a release button in the gripping handle, the release button being connected to respective cables and spring biased pins adapted to selectively lock and release the second and third stage tubes in selected positions. Preferably, the second and third stage tubes are aluminum. 
         [0016]    The first stage extruded tubes include a plurality of inwardly extending radial members to provide reinforcement to the tubes. Further, the extruded tubes are polyvinyl chloride and the metal strips and aluminum insert reinforcement strips. The aluminum reinforcement insert strips preferably include top and bottom end portions which are bent over the respective edges of said extruded tubes to retain the strips in position in the tube. 
         [0017]    A telescopic handle system for a trolley-type carry-case is disclosed, which comprises at least a first stage extruded plastic tubular member, the extruded plastic tubular member defining a generally central tubular opening having an inner tubular surface, the tubular member has positioned on the inner surface of the inner opening, a pair of generally opposed reinforcement strips made of a material of strength greater than the material of said tubular member. Each reinforcement strip has a generally radially extending retention member positioned along each side thereof to retain the reinforcement strip in position on the inner surface of the tubular member. Each reinforcement strip has a plurality of apertures of predetermined size and relative locations for selective reception of spring biased pins associated with a respective second and third stage members of the telescoping handle system. 
         [0018]    A trolley-type carry case having a three stage telescopic handle system is disclosed, which comprises a container for reception and retention of selected articles, and a telescopic handle system attached to the container. The handle system comprises at least a first stage extruded plastic tubular member, the extruded plastic tubular member defining a generally central tubular opening having an inner tubular surface. The tubular member has positioned on the inner surface of the inner opening, a pair of generally opposed reinforcement strips made of a material of strength greater than the material of the tubular member. Each reinforcement strip has a generally radially extending retention member positioned along each side thereof to retain the reinforcement strip in position adjacent the inner surface of the tubular member. Each said reinforcement strip has a plurality of apertures of predetermined size and relative locations for reception of spring biased pins associated with a respective second and third stage members of said telescoping handle system. The container is preferably an article of luggage. 
       The Present Invention: Third Generation: Back to Extrusions 
       [0019]    The present invention relates to a first stage of a telescoping handle for a carry case having a combination of a pair of extruded plastic (i.e., ABS, or other extrudable plastic) tubes which include elongated lengthwise ribs, some of which in combination, form channels which are dimensioned to substantially snuggly receive lengthwise insert strips of a material having greater strength and wear resistance than that of the tube. In the preferred embodiment, the insert strips extend over the same length as the extruded plastic tube, or are slightly longer to permit binding the top portions over to retain the insert strip in position. In another embodiment, the insert strips can be of length less than that of the tube. 
         [0020]    While the insert strips can be of any material of greater strength and wear resistance than the extruded plastic tube, a metal, such as aluminum or cold rolled steel can be used. Presently aluminum is preferred. Any material of sufficient strength can be used, as will be described hereinbelow. 
         [0021]    In particular, the metal insert strips contain apertures of predetermined dimension and relative locations, for reception of the spring loaded locking pins of the telescoping mechanism, and they are therefore adapted to withstand the loads provided by the spring loaded pins when they enter the apertures in the metal strips, as well as when the carry case is wheeled from place to place. Accordingly, the combination of the extruded plastic tubes and the metal insert strips provide stability for accommodating carry cases of all sizes. 
         [0022]    Also, the metal strips engage thesecond stage tube as it enters and exits the first stage, to thereby provide guidance for the second stage, and wear resistance from the periodic rubbing of the second stage when it slidably enters the first stage tube. 
         [0023]    Additionally, while the plastic extrusion of the first stage has an appearance which blends with the remaining components of the carry case, the stronger metal insert strips which help to carry the loads are not apparent to the eye of the observer and do not detract from the aesthetic appearance of the telescoping handle with respect to the bag. 
         [0024]    The channel ribs, as well as the remaining inwardly extending radial ribs of the extruded tube also add strength to the tubes. Optionally, the radial ribs can also be made long enough to provide additional guidance for the second stage tube as it enters the first (or lowermost stage) as will be described in further detail. 
         [0025]    The tube of the present invention is considered to be “modular” because it can be molded in any length and cut to specific sizes, as needed, along with the same size metal inserts. This feature is in contrast to the prior art tubes, where individual molds had to be made for each different length tube which respectively applied to different types of carry cases. 
         [0026]    In summary, the extruded tube is strengthened by:
       a) The plurality of internal radially extending ribs;   b) The inserted strips of metal, which can be either aluminum or cold rolled steel, or any strong material. Nylon, polyvinyl chloride (PVC), polyethylene or polycarbonate type materials are also contemplated for the insert strips, provided they are of sufficient strength to enhance the strength of the extended tubes. Presently, aluminum is preferred.   c) The insert strips of metal also provide sliding contact with the second stage tube as it enters and exits the first stage tube, thereby guiding the second stage tube with a relatively wear-resistant surface.       
 
         [0030]    In one embodiment, each strip of metal is approximately 1 mm (i.e., millimeters) in thickness and 1.5 cm (i.e., centimeters) in width. They fit snuggly within each channel which is formed by a pair of molded ribs. Preferably the insert strips are made slightly longer than the tubes so as to facilitate folding an end portion over the top and bottom end faces of the tube to retain them in position, longitudinally as shown in  FIG. 7 . 
         [0031]    The metal strips in effect, provide an extra reinforcing factor, since most bending forces applied to the metal strips will generally be about an axis perpendicular to the metal strip when moving the carry case over uneven terrain. In two stage applications, one reinforcement insert strip may be used. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0032]    Preferred embodiments of the invention are described hereinbelow with reference to the drawings, wherein: 
           [0033]      FIG. 1  is a top perspective view of a trolley-type carry case, showing the telescoping handle of the present invention in its collapsed condition; 
           [0034]      FIG. 2  is an enlarged view with parts separated for illustration purposes, of an extruded plastic tube that retains two metal strips that extend downwardly along each side of the plastic tube for added strength, each metal strip having apertures dimensioned and positioned to receive spring loaded locking pins therein when the handle sections are extended for use; 
           [0035]      FIG. 3  is an enlarged cross-sectional view taken along lines  3 - 3  of  FIG. 2 , showing the two metal strips of  FIG. 2  in position, and also showing the two telescoping upper second and third stage handle tubes in phantom which are generally made of aluminum; this Fig. also illustrates the guiding function of the metal inserts with respect to the second stage tube as it enters and exits the first stage tube while contacting the first stage tube; 
           [0036]      FIG. 4  is an elevational view of the gripping handle portion of the telescopic handle, taken along lines  4 - 4  of  FIG. 1 , and showing how by pressing the button at the top, the cables which extend downwardly along each side of the telescopic tubes move upwardly to release their respective spring loaded locking pins; 
           [0037]      FIG. 5  is a cross-sectional view, taken along lines  5 - 5  of  FIG. 1 , and illustrating the locking mechanism of the telescopic handle according to the present invention in the collapsed condition; 
           [0038]      FIG. 6  is a cross-sectional view of the mechanism of  FIG. 5 , illustrating movement of the initial locking mechanism and the third (or innermost) tube, when the release button located at the top of the gripping is depressed and the third tube is pulled upwardly; 
           [0039]      FIG. 7  is a cross-sectional view of the locking mechanism, showing the third (or innermost) tube approaching the next (or middle) locking position; 
           [0040]      FIG. 8  is a top perspective view of the trolley-type carry case of.  FIG. 1 , with telescopic handle of the present invention shown in the fully extended condition; 
           [0041]      FIG. 9  is a cross-sectional view taken along lines  9 - 9  of  FIG. 8 , and illustrating the locking pin mechanism when the handle is in the fully extended condition, with the second and third stage tubes fully withdrawn from the first tube; and 
           [0042]      FIG. 10  is a perspective view of an alternative embodiment of the reinforcing metal strip of the invention, used for the locking pins, the metal strip being shorter in length and intended for use with tubes of greater strength, by virtue of utilizing either a plastic material of greater strength for the extruded tube, or a tube wall of greater thickness, or a combination of both features, said metal strip being used in combination with a similar short metal strip positioned opposite the first strip to provide the same pattern of apertures for the locking pins as is provided by the larger strips. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0043]    Referring initially to  FIG. 1 , there is shown a perspective view showing the handle of the present invention in its collapsed condition. 
         [0044]      FIG. 2  shows an enlarged view of the first stage extruded plastic tube of the handle of  FIG. 1 , which retains two opposed metal strips which extend downwardly along each opposed inner side of the extruded plastic tube for added strength. Each metal strip has apertures for reception of locking pins which become aligned therewith. Moreover, the extruded plastic tube includes radially inwardly extending ribs for added strength. 
         [0045]      FIG. 3  is an enlarged cross sectional view, taken along lines  3 - 3  of  FIG. 2 . This enlarged view shows the two metal strips in place, as well as the two telescopic handle second and third stage  16 ,  18  tubes in phantom. As the second and third stage aluminum tubes  16 ,  18  enter and exit the first stage tube  12 , the second stage tube is guided by metal inserts  28 ,  30  as contact is made with the wear resistant surfaces of the metal strips  28 ,  30 . This contact is made in the areas marked “A” and “B” in  FIG. 3  which show the spaces as somewhat exaggerated, between the second stage tube and the metal insert strips. However, in reality these spaces are minimal, and provide continuous guidance for the second stage tube as it enters and exits the first stage tube. The metal insert strips provide lasting wear resistant surfaces as compared to the inner components of the extruded plastic tube. 
         [0046]      FIG. 4  is an elevational view of the handle portion, taken along lines  4 - 4  of  FIG. 1 . This view shows how by pressing the button at the top will pull on the cables that extend downwardly along each side of the telescopic tubes to apply tension to the cables to withdraw their respective spring loaded release pins as shown. 
         [0047]      FIG. 5  is a partial cross-sectional view, taken along lines  5 - 5  of  FIG. 1 . In this view all of the parts of the telescopic handle are in their collapsed and locked position. When the innermost (i.e., third stage) tube is fully withdrawn, it will press downwardly against on the bottom locking stopper in the second stage telescoping tube. When this takes place, the secondary pin locks into the outer metal strip, pulling into its housing the primary pin. This view also shows the stopper at the bottom of the innermost tube, with its locking pin engaging the left side of the second telescopic tube. 
         [0048]      FIG. 6  shows the movement of the locking mechanism when the release button on the handle is pressed to provide camming action to pull the cable upwardly, to in turn permit the user to pull the third stage (i.e., innermost) tube upwardly. The innermost third stage locking pin of the third stage tube is released through the cable action, and the innermost telescopic tube starts moving up manually. This view also shows that when this movement takes place, the secondary locking pin (i.e., the lower locking device) moves inwardly and unlocks the second telescopic tube, so that the second telescopic tube is released for upward manual movement with the second stage in tandem with the third stage tube when the locking pin associated with the third stage enters the aperture of the second stage, the second stage moves upwardly with the third stage. 
         [0049]      FIG. 7  shows the innermost third stage tube reaching the next locking position. When this movement takes place, the locking pin of the innermost third stage tube passes through the second stage tube wall and then through the aperture in the inner metal strengthening strip positioned in place on the first stage (i.e., lowermost) tube. At this point the handle is at the middle height position. 
         [0050]      FIG. 8  is a top perspective view of the trolley-type carry case of  FIG. 1 , with the telescoping handle in the fully extended and locked condition. 
         [0051]      FIG. 9  is a cross sectional view, taken along lines  9 - 9  of  FIG. 8 , and illustrating the locking mechanism attached to the innermost (i.e., third stage) tube, when locked into the second telescopic tube. At the bottom of the second telescopic tube, it can be seen that its primary locking pin  33  has moved to the left, thereby locking into the aperture  32  of the inner, or left metal strip attached to the first stage tube. At this point the handle is at its fully extended height. 
         [0052]      FIG. 10  is a perspective view of an alternative embodiment of the invention, showing a short metal strip used in place of the long metal strips for reception of the locking pins. This strip could be used in combination with a similar opposed short metal strip in a first stage plastic housing tube made of a higher strength plastic, or having a greater wall thickness which would obviate the need for the additional strength provided by the longer metal strips. 
         [0053]    Referring again to  FIGS. 1 and 8 , the trolley-type carry case  10  includes telescopic handle  11  having a pair of parallel tubes, each comprised of three stages, stage  1 , designated as  14 , stage  2 , designated as  16 , and stage  3 , designated as  18 . 
         [0054]    The present invention relates primarily to the tube  12  of the first stage  14 , which is made of an extruded plastic outer tubing  14  shown in cross-section in  FIG. 3 , and having radially inwardly extending internal ribs  20 ,  22  and  24 . Ribs  20  provide reinforcement to the tube  12 . Ribs  22  and  24  each include an inward radial extension  24 , as well as a circumferential extension  26 . Ribs  22  are therefore configured in this manner to retain metal reinforcing strips  28 ,  30 , which are preferably made of aluminum, but which can be of any alternative material such as cold rolled steel, or high strength plastic, such as nylon, polyvinyl chloride (i.e., PVC), polyethylene, polycarbonate, or the like. Furthermore, as can be seen in the cross-sectional view of  FIG. 3 , metal strip  30  differs somewhat in cross-section from metal strip  28  to accommodate the shape of extruded tube  12 ; however both strips  28 ,  30  have a generally “hat-like” cross-sectional shape. 
         [0055]    It can be appreciated that extruded tube  12  is clearly reinforced by metal strips  28 ,  30  which also include apertures  32 ,  34 ,  36  respectively (see  FIG. 2 ) for reception of the spring loaded locking pins of the telescoping mechanism in the extended, intermediate, and collapsed conditions, respectively, as can be seen in the cross-sectional views of  FIGS. 4-9 . It can also be appreciated that the reinforced lightweight extruded plastic tubes of the present invention now make it possible (via the metal strips  28 ,  30 ) to provide the higher strength apertures for reception of the spring loaded locking pins  19 ,  25 ,  33 . 
         [0056]      FIG. 10  illustrates an alternative embodiment  37  of the metal strips  30 ,  36  of  FIG. 2 , which can be used with extruded or molded plastic tubes made of high strength plastic. In such case, the tube reinforcing feature of the metal strips will not be needed. However, the metal pin reception apertures  38  of strip  37  are provided to receive the locking pins  25 ,  33  in the same manner as the longer metal strips of  FIG. 2 . Two similar shorter metal strips (one not shown) can be provided on the opposite sides of the plastic tube to provide locking apertures in the same locations as shown with the longer metal strips  30 ,  36  of  FIG. 2 . 
         [0057]    Referring again to  FIGS. 4-7 , the locking mechanism for the three stage telescoping handle is illustrated. 
         [0058]    The complete telescopic handle  11  is comprised of parallel spaced apart three stage telescoping sections  14 ,  16 ,  18 , connected at their upper ends by transverse gripping handle  15 , which houses the controlling mechanism  40  for releasing the telescoping mechanism which is activated by depressing button  17  on gripping handle  15 , for example, when the three stage telescoping handle is in the collapsed condition as shown in  FIG. 1 . In this condition the locking mechanism at the base of the first stage  14  is as shown in  FIG. 5 , i.e., with the locking pin  19  of lower locking mechanism  21  positioned in aperture  36  of metal strip  28 , while the locking pin  25  of upper locking mechanism  23  is positioned in the aperture  27  of the second stage tube  16 . 
         [0059]    In  FIGS. 6-9 , the button  17  of  FIGS. 4 and 8  has been depressed, the dual action camming device in the gripping handle pulling cable  13  upwardly, and through the springs and camming mechanisms shown in  FIGS. 5-9 , the third stage tube  18  can begin manual movement upwardly until locking pin  25  of locking mechanism  23  enters aperture  35  of second stage tube  16 . 
         [0060]    Thereafter second stage tube  16  is pulled upwardly with third stage tube  18  until metal locking pin  33  of lower locking mechanism  21  enters aperture  32  of metal strip  30 , such that the telescoping handle is in the fully extended condition. Metal strips  28 ,  30  each have more than one optional aperture to provide for fine adjustments, if needed. 
         [0061]    By depressing button  17 , the locking pins  25 ,  33  are withdrawn respectively from their apertures via the button operated ramming and spring mechanism shown, thereby permitting the operator to manually collapse the three stage handle to the condition shown in  FIG. 1 . 
         [0062]    It can be appreciated that the first stage telescopic tube of the present invention, reinforced by metal strips  30 ,  36 , makes it possible to provide a lighter weight first stage tube, combined with greater strength for carrying substantially the entire load of the telescopic system through the unique combination of the extruded plastic tube and the metal strips which are retained in position by the radially inwardly extending flanges which are molded monolithically with the first stage tubes. This feature provides a significant increase in strength, combined with a correspondingly significant decrease in weight, without loss of esthetics. 
         [0063]    Furthermore, the extruded tubes can be molded to any length and cut to size to custom fit any particular size carry case without the need to produce customized molds. The metal strips can similarly be cut to size to fit any size carry case. In addition, the unique first stage tubes of the present invention can also be incorporated into telescopic handles comprised of alternative number of stages, i.e., 2 stage, 4 stage, etc. 
         [0064]    The present invention can also be used with individually molded tubes, or tubes of any material requiring strength enhancement. However, it is best configured for use with extruded first stage tubes.