Abstract:
A stagelessly adjustable telescopic waking stick having a position retaining device is made up of an upper pipe and a lower pipe that are telescopically adjusted so as to permit the walking stick to be extended to any length within a limited range and be firmly retained at any selected length by the position retaining device so as to permit the telescopic walking stick to be suitable to people of various physical sizes.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a stagelessly adjustable telescopic walking stick having a position retaining device so as to permit the walking stick to be extended to any length within a limited range and be firmly retained at any selected length so as to permit the telescopic walking stick to be used by people of various physical sizes. 
     In general, walking sticks are manufactured in a number of fixed sizes and people of different physical sizes must choose a proper walking stick best meet their physical sizes. Such way of producing walking sticks of fixed sizes make the stocks in the warehouse of a factory or stores piled up easily. 
     To solve the problem, length adjustable walking sticks have been developed for many years. The conventional adjustable walking sticks are designed to have an upper pipe and a lower pipe having a plurality of evenly spaced retaining holes defined thereon. The upper pipe is equipped with a pair of retractable locking buttons which can be in selective engagement with the retaining holes of the lower pipe, making the walking stick adjustable in length. 
     However, this prior art walking stick has a number of inherent disadvantages given as below: 
     1. The evenly spaced retaining holes on the lower pipe are not defined in such a manner that a precise length can be easily obtained in one aspect; and the operation on the retaining buttons and the selection of proper retaining holes are relatively difficult for the aged people in another aspect. 
     2. The disposition of the retaining holes on the lower pipe makes the strength of the lower pipe weakened and the surface of the same spoiled. 
     3. The drilling of the retaining holes on the lower pipe makes the production of a walking stick complex and the manufacturing cost thereof relatively high. 
     4. A personal walking stick is usually used only by an individual constantly and the retaining holes are almost fixed without shift, rendering easy damage to the retaining holes and shortening the operation life of such a walking, stick after a period of time. 
     The inventor has noticed such problems associated with conventional walking sticks and came up with a stagelessly adjustable walking stick equipped with specific position retaining devices as disclosed in the present invention. 
     SUMMARY OF THE INVENTION 
     Therefore, the primary object of the present invention is to provide a stagelessly adjustable walking stick having a position, retaining device which enables a user to vary the length of the walking stick in a random manner within a limited range. 
     Another object of the present invention is to provide a stagelessly adjustable walking stick having a position retaining device equipped with an eccentrically driven retainer and having an expandable plastic tube having inner threads. The plastic tube is made up of two separable portions bound together by a C-shaped clamp, one portion has an eccentrically located engagement protrusion to which an eccentric circular disk is secured by a screw. A cone-shaped taper means having one end secured to one end of a lower pipe of a walking stick and having the other end provided with a threaded post which can be engaged with the inner threaded face of the plastic tube and make the taper means proceed forwardly or withdraw backwardly, resulting in the outward expansion of the clamp bound plastic tube when the lower pipe is rotated to move upwardly, making the eccentric circular disk and the eccentric retainer both housed in the upper pipe abut against the inner wall of the upper pipe respectively in such a manner that the retainer of the taper means mounted onto the end of the lower pipe can proceed forwardly to expand outwardly the plastic tube whereby the upper pipe and the lower pipe can be firmly locked together by the expanded plastic tube at a selected length. 
     One further object of the present invention is to provide a stagelessly adjustable walking stick having a position retaining device having an eccentric circular disk secured to an eccentrically operated retainer having an eccentric securing member for the fixing of the circular disk by a screw. The retainer has a tapered face at the top with an inner threaded tubular extension projected downwardly therefrom so that a taper means attached to the end of the lower pipe and having an outerly threaded post projected therefrom can adjustably engaged with the retainer. A plastic locking tube having a longitudinally split opening is disposed between the eccentric retainer and the taper means whereby when the eccentric circular disk and the retainer are housed in the upper pipe of a walking stick, the split plastic tube will be forced to outwardly expand to abut tightly against the inner wall of the upper pipe as a result of the taper means secured to the lower pipe proceeding forwardly due to the rotation of the lower pipe by a person. The eccentric circular disk and the eccentric retainer are designed to abut firmly against the inner wall of the upper pipe when the lower pipe is rotated to make the outerly threaded post of the taper means engaged with the innerly threaded tubular extension, making the eccentric circular disk and the eccentric retainer rotated separately to such a position that the eccentric circular disk and the eccentric retainer are in a locking abutment against the inner wall of the upper pipe, guaranting the taper means to be able to effectively proceed against the plastic locking tube to make the same outwardly expanded. 
     One still further object of the present invention is to provide a stagelessly adjustable walking stick having a position retaining device that is equipped with a plastic retainer cap having a tubular passage. The plastic retainer cap is divided into four symmetric portions by two orthogonally defined splitting cuts crisscrossing at the summit of the cap. The tubular passage is provided with inner threads on the wall thereof so as to permit a threaded post having a tapered end and secured to the top end of the lower pipe to be rotatably engaged with the plastic retainer cap. The innerly threaded tubular passage extends most of the plastic retainer cap with a section thereof, adjacent the four portion split top end, left blank whereby when the tapered end of the threaded post is made to move forwardly as a result of the rotation of the lower pipe, the four split portions of the plastic retainer cap are urged to outwardly expand to firmly abut against the inner wall of the upper pipe so as to lock the lower pipe in position to the upper pipe after a suitable length of the walking stick is selected. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective diagram showing the stagelessly adjustable walking stick of the present invention; 
     FIG. 2 is a diagram showing the assembly of the first embodiment of the present invention; 
     FIG. 3 is a perspective diagram showing the exploded components of the first embodiment thereof; 
     FIG. 4 is a sectional diagram showing the practical operation of the first embodiment; 
     FIG. 5A is a sectional diagram showing the eccentric circular disk and the eccentric retainer being placed in a state without firm abutment against the inner wall of the upper pipe; 
     FIG. 5B is another sectional diagram showing both the eccentric circular disk and the eccentric retainer being placed in locking abutment against the inner wall of the upper pipe; 
     FIG. 6 is a diagram showing the second embodiment of the present invention; 
     FIG. 7 is a perspective diagram showing the exploded components of the second embodiment thereof; 
     FIG. 8 is a sectional diagram showing the operation of the second embodiment thereof; 
     FIG. 9 is a perspective diagram showing the plastic locking tube having a longitudinal split opening; 
     FIG. 10 is a perspective diagram showing the exploded components of the third embodiment thereof; 
     FIG. 10a is a perspective view showing the plastic retainer cap of the present invention; 
     FIG. 11 is a sectional diagram showing the inner structure of the plastic retainer cap; 
     FIG. 12 is a sectional diagram showing the operation of tapered end of the threaded post moving against the split top end to make the retainer cap outwardly expand. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIG. 1, the stagelessly adjustable walking stick  1  of the present invention comprised of a handle  2 , as upper pipe  3 , a lower pipe  4  is randomly extended or retracted of its lower pipe  4  within a limited range and is locked in position at a selected length with ease. 
     In the first embodiment of the present invention as shown in FIGS. 2,  3 , the walking stick  1  having a position retaining device  5  which enables a user to vary the length of the walking stick in a stageless manner. The position retaining device  5  is comprised of an retainer  7  including a round securing plate  74  in connection to a half cylindrical extension  72 a, and another separated half cylindrical portion  72 b in match with the cylindrical extension  72 a. 
     Both the half cylindrical extension  72 a and the half cylindrical portion  72 b are provided with inner threads  77  and an outer groove  71  at the middle thereof and a tapered face  78  at one end respectively so as to form an expandable plastic tube having inner threads and a tapered bottom when the two separable portions  72 a,  72 b are bound together by a C-shaped clamp  73 . On the top of the round securing plate  74  is disposed an eccentric engagement protrusion  76  having a screw hole  75  so as to permit a circular disk  8  having an eccentric hole  81  defined thereon to be secured by a screw  10  with a washer  9  located therebetween. A conic taper means  6  having a connection joint  61  at one end for engagement with one end of the lower pipe  64  of a walking stick and having the other end provided with a conic tapered face  62  in connection to a threaded post  63  which can be engaged with the inner threaded face  77  of the plastic tube and make the taper means  6  proceed forwardly or withdraw backwardly, resulting in the outward expansion of the clamp bound plastic tube when the lower pipe  4  is rotated to move upwardly. 
     Referring to FIGS. 5a,  5 b, in the beginning, the eccentric circular disk  8  and the round securing plate  74  of the retainer  7  are placed in leaning against the sample side of the inner face of the upper pipe; the rotation of the lower pipe  4  will make the eccentric circular disk  8  and the eccentric retainer  7  fully abut against the inner wall of the upper pipe  3  respectively in such a manner that the taper means  6  mounted onto the end of the lower pipe  4  can proceed forwardly to expand outwardly the plastic tube by the conic tapered face  62  of the taper means  6  as long as the lower pipe  4  is further rotated whereby the upper pipe and the lower pipe can be firmly locked together by the expanded plastic tube at a selected length. 
     Referring to FIGS. 6,  7 , a second embodiment of the present invention is equipped with a position retaining device  5  having a circular disk  8  with an eccentric hole  81  and secured to an eccentrically operated retainer  12 . The retainer  12  having an eccentric securing plate  122  for the fixing of the circular disk  8  by a screw  10 . The retainer  12  has a conically tapered face  123  with an innerly threaded tubular extension  121  projected downwardly therefrom. On top of the securing plate  122  is erected a tubular protrusion  125  having a screw hole  124  for fixing the circular disk  8 . A taper means  6  having a conically tapered face  62  and an outerly threaded post  63  extended therefrom is attached to the end of a lower pipe  4  by way of a joint block  61  and can adjustably engaged with the retainer  5 . A plastic locking tube  11  having a longitudinally split opening  111  and a central hole  112  and a tapered periphery  113  at each end thereof is disposed between the eccentric retainer  12  and the taper means  6  whereby when the eccentric circular disk  8  and the retainer  12  bound together by way of the screw  10  and the washer  9  are housed in the upper pipe  3  of a walking stick the split plastic tube  11  will be forced to outwardly expand to abut tightly against the inner wall of the upper pipe  3  as a result of the taper means  6  secured to the lower pipe  4  proceeding forwardly due to the rotation of the lower pipe  4  by a person. 
     In other words, the eccentric circular disk  8  and the eccentric retainer  12  are designed to be in linear alignment with each other but the eccentric circular disk  8  and the securing plate  122  of the retainer  12  are made to separately abut firmly against the inner wall of the upper pipe  3  when the lower pipe  4  is rotated to make the outerly threaded post  63  of the taper means  6  engaged with the linearly threaded tubular extension  121 , making the eccentric circular disk  8  and the eccentric retainer  12  rotated out of linear alignment, as shown in FIG. 5b, to abut tightly against the inner wall of the upper pipe  3 , guaranting the taper means  6  to be able to effectively proceed forwardly into the plastic locking tube  11  to make the same outwardly expanded. 
     Referring to FIGS. 9,  10 ,  10 a,  11 , the third embodiment of the present invention is equipped with a plastic retainer cap  13  having a tubular passage  133   132 . The plastic retainer cap  13  is divided into four symmetric portions  134  by two orthogonally defined splitting cuts  131 . The tubular passage  132  is provided with inner threads  133  on the wall thereof so as to permit a threaded post  14  having a tapered end  141  and secured to the top end of the lower pipe  4  by the joint block  142  to be rotatably engaged with the plastic retainer cap  13 . The innerly threaded tubular passage  132  extends most of the plastic retainer cap  13  with a section  135  thereof, adjacent the. four-portion split top end, left blank whereby when the tapered end  141  of the threaded post  14  is made to move forwardly as a result of the rotation of the lower pipe  4 , the four split portions  134  of the plastic retainer cap  13  are urged to outwardly expand to firmly abut against the inner wall of the upper pipe  3  so as to lock the lower pipe  4  in position to the upper pipe  3  after a suitable length of the walking stick is selected. The action of the split portions being urged outwardly is shown in FIGS. 11 and 12.