Tube-adjusting device

Abstract

A tube-adjusting device includes a tubular guide having a longitudinal line of apertures and a longitudinal groove diametrically opposite to the line of apertures. A tube extends in the tubular guide and has an inner transverse column defining a through-hole aligned with alternative one of the apertures and with the longitudinal groove of the guide. The inner transverse column has a threaded inner wall adjacent to the longitudinal groove. A pin is movable in the through-hole of the inner transverse column, and has a rounded end adapted to engage the apertures of the guide. A thumbscrew has a threaded shank extending into the through-hole in the transverse column through the longitudinal groove, and is threadedly engaged with the threaded inner wall. Additionally, a helical spring is received in the through-hole of the inner transverse column and compressed between the pin and the threaded shank of the thumbscrew.

What is claimed is:  
     
         1 . A tube-adjusting device comprising: 
 a tubular guide ( 30 ) having at least one open end ( 31 ), said guide ( 30 ) being formed with a longitudinal line of apertures ( 34 ) and a longitudinal groove ( 35 ) substantially parallel to and diametrically opposite to said longitudinal line of said apertures ( 34 );    a tube ( 40 ) extending partially in said tubular guide ( 30 ) through said open end ( 31 ), said tube ( 40 ) having an inner transverse column ( 42 ) defining a through-hole ( 43 ) in alignment with alternative one of said apertures ( 34 ) and with said longitudinal groove ( 35 ) of said guide ( 30 ), said inner transverse column ( 42 ) having a threaded inner wall ( 431 ) adjacent to said longitudinal groove ( 35 ) for defining a portion of said through-hole ( 43 );    a pin ( 20 ) movable in said through-hole ( 43 ) of said inner transverse column ( 42 ), said pin ( 20 ) having a rounded end ( 23 ) adapted to engage with alternative one of said apertures ( 34 ) of said guide ( 30 );    a thumbscrew ( 10 ) having a threaded shank ( 12 ) extending into said through-hole ( 43 ) in said inner transverse column ( 42 ) of said tube ( 40 ) through said longitudinal groove ( 35 ) of said tubular guide ( 30 ), said threaded shank ( 12 ) being threadedly engaged with said threaded inner wall ( 431 ) of said inner transverse column ( 42 ); and    a helical spring ( 24 ) received in said through-hole ( 43 ) of said inner transverse column ( 42 ) and compressed between said pin ( 20 ) and said threaded shank ( 12 ) of said thumbscrew ( 10 ).    
     
     
         2 . The tube-adjusting device as claimed in  claim 1 , wherein said thumbscrew ( 10 ) has a knob ( 11 ) from which said threaded shank ( 12 ) extends.  
     
     
         3 . The tube-adjusting device as claimed in  claim 2 , wherein said pin ( 20 ) has a reduced end ( 21 ) opposed to said rounded end ( 23 ), and wherein said helical spring ( 24 ) is mounted at least partially around said pin ( 20 ) at said reduced end ( 21 ).  
     
     
         4 . The tube-adjusting device as claimed in  claim 3 , wherein said tubular guide ( 30 ) has a pair of longitudinal slots ( 36 ) defined at sides of said longitudinal groove ( 35 ), and wherein said tube ( 40 ) is formed with a pair of wheels ( 45 ) rotatable along said longitudinal slots ( 36 ) of said guide ( 30 ).  
     
     
         5 . The tube-adjusting device as claimed in  claim 4 , wherein said tubular guide ( 30 ) further has a secondary wheel ( 32 ) formed adjacent to said open end ( 31 ) to support said tube ( 40 ).