Patent Publication Number: US-2017368705-A1

Title: Tube Cutter with Automatically Feeding Function

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a cutter and, more particularly, to a tube cutter for cutting a tube. 
     2. Description of the Related Art 
     A conventional tube cutter comprises a substantially U-shaped main body having a first end provided with a screw hole, a cutting wheel mounted on a second end of the main body, a slide movably mounted on the main body, two rollers mounted on the slide and aligning with the cutting wheel, and a threaded rod screwed through the screw hole of the main body and having a first end resting on the two rollers, and a control knob secured on a second end of the threaded rod. In operation, when the threaded rod is rotated by the control knob, the threaded rod is moved axially relative to the main body to drive the two rollers which drive the slide to move on the main body, so that the two rollers are moved relative to the cutting wheel. Thus, when the tube cutter is mounted on a tube, the two rollers rest on the tube. Then, the threaded rod is rotated by the control knob, and the two rollers are moved toward the cutting wheel, so that the tube is clamped between the two rollers and the cutting wheel. Then, the main body is held by the user&#39;s hand and is rotated relative to the tube, so that the cutting wheel is revolved on the tube so as to shear the tube gradually and successively until the tube is cut. However, the conventional tube cutter does not have an automatically feeding function so that the user has to rotate the control knob successively to move the two rollers to press the tube during the shearing process, thereby causing inconvenience to the user, and thereby wasting the energy and working time. 
     BRIEF SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a tube cutter with an automatically feeding function. 
     In accordance with the present invention, there is provided a tube cutter comprising a main body, a holder, a guide bolt and two rollers. The main body includes a horizontal portion and a vertical portion. The main body is provided with a horizontal receiving channel and a vertical receiving channel. The horizontal portion has a wall provided with a screw hole. The holder is slidably mounted in the horizontal receiving channel of the main body. The holder has a mediate position provided with a through hole aligning with the screw hole. The holder is provided with a mounting groove, and a cutting wheel is rotatably mounted in the mounting groove and corresponding between the two rollers. The mounting groove has a first sidewall provided with a through bore and a second sidewall provided with a screw bore coaxial with the through bore. The cutting wheel is provided with a shaft bore, and a screw extends through the through bore and the shaft bore and is screwed into the screw bore. The guide bolt is screwed through the screw hole of the main body and extends through the through hole of the holder. The guide bolt has a first end provided with a rotation portion protruding from the screw hole of the main body and a second end provided with a resting portion protruding from the through hole of the holder. An elastic member is mounted on the guide bolt and is biased between the resting portion and the holder. The two rollers are rotatably mounted on the main body. 
     According to the primary advantage of the present invention, the holder is pushed by the elastic force of the elastic member, so that the cutting wheel is fed toward the tube automatically during the cutting process, so as to shear the tube successively until the tube is cut, thereby facilitating the user operating the tube cutter to cut the tube. 
     Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
         FIG. 1  is a perspective view of a tube cutter in accordance with the first preferred embodiment of the present invention. 
         FIG. 2  is an exploded perspective view of the tube cutter as shown in  FIG. 1 . 
         FIG. 3  is a cross-sectional view of the tube cutter as shown in  FIG. 1 . 
         FIG. 4  is a schematic operational view of the tube cutter as shown in  FIG. 3 . 
         FIG. 5  is a schematic operational view of the tube cutter as shown in  FIG. 4 . 
         FIG. 6  is a schematic operational view of the tube cutter as shown in  FIG. 5 . 
         FIG. 7  is a schematic operational view of the tube cutter as shown in  FIG. 6 . 
         FIG. 8  is a schematic operational view of the tube cutter as shown in  FIG. 7 . 
         FIG. 9  is a perspective view of a tube cutter in accordance with the second preferred embodiment of the present invention. 
         FIG. 10  is an exploded perspective view of the tube cutter as shown in  FIG. 9 . 
         FIG. 11  is a cross-sectional view of the tube cutter as shown in  FIG. 9 . 
         FIG. 12  is a perspective view of a tube cutter in accordance with the third preferred embodiment of the present invention. 
         FIG. 13  is an exploded perspective view of the tube cutter as shown in  FIG. 12 . 
         FIG. 14  is a cross-sectional view of the tube cutter as shown in  FIG. 12 . 
         FIG. 15  is a cross-sectional view of the tube cutter taken along line F-F as shown in  FIG. 14 . 
         FIG. 16  is a perspective view of a tube cutter in accordance with the fourth preferred embodiment of the present invention. 
         FIG. 17  is an exploded perspective view of the tube cutter as shown in  FIG. 16 . 
         FIG. 18  is a cross-sectional view of the tube cutter as shown in  FIG. 16 . 
         FIG. 19  is a cross-sectional view of the tube cutter taken along line B-B as shown in  FIG. 18 . 
         FIG. 20  is a schematic operational view of the tube cutter as shown in  FIG. 18 . 
         FIG. 21  is a schematic operational view of the tube cutter as shown in  FIG. 20 . 
         FIG. 22  is a schematic operational view of the tube cutter as shown in  FIG. 21 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings and initially to  FIGS. 1-3 , a tube cutter in accordance with the preferred embodiment of the present invention comprises a main body  10 , a holder  20 , a guide bolt  30  and two rollers  40 . 
     The main body  10  has a substantially L-shaped profile and includes a horizontal portion  11  and a vertical portion  12 . The main body  10  is provided with a horizontal receiving channel  13  and a vertical receiving channel  14 . The horizontal portion  11  has a wall corresponding to the vertical portion  12  and provided with a screw hole  16 . The vertical receiving channel  14  has two sidewalls each provided with two pivot holes  17 . 
     The holder  20  is slidably mounted in the horizontal receiving channel  13  of the main body  10  so that the holder  20  is moved forward and backward in the horizontal receiving channel  13  of the main body  10 . The holder  20  has a mediate position provided with a through hole  23  aligning with the screw hole  16 . The holder  20  is provided with a mounting groove  24 , and a cutting wheel  25  is rotatably mounted in the mounting groove  24  and corresponding between the two rollers  40 . The mounting groove  24  has a first sidewall provided with a through bore  26  and a second sidewall provided with a screw bore  27  coaxial with the through bore  26 . The cutting wheel  25  is provided with a shaft bore  28 , and a screw “P” extends through the through bore  26  and the shaft bore  28  and is screwed into the screw bore  27 . 
     The guide bolt  30  is screwed through the screw hole  16  of the main body  10  and extends through the through hole  23  of the holder  20 . The guide bolt  30  has a first end provided with a rotation portion  31  protruding from the screw hole  16  of the main body  10  and a second end provided with a resting portion  32  protruding from the through hole  23  of the holder  20 . The guide bolt  30  is rotated by the rotation portion  31 . An elastic member “S” is mounted on the guide bolt  30  and is biased between the resting portion  32  and the holder  20 . 
     The two rollers  40  are mounted on the main body  10  by two pivot members “Q”. Each of the two rollers  40  is provided with a shaft hole  41 . The two pivot members “Q” extend through the pivot holes  17  of the main body  10  and the shaft holes  41  of the two rollers  40 , so that the two rollers  40  are rotatable freely in the vertical receiving channel  14  of the main body  10 . 
     In the preferred embodiment of the present invention, the holder  20  has a bottom provided with two stepped rails  21  resting on a bottom of the horizontal portion  11  and has a side provided with a slideway  22 , the horizontal receiving channel  13  has a sidewall provided with an aperture  15 , and a positioning pin (not shown) extends through the aperture  15  of the main body  10  and positioned in the slideway  22  of the holder  20 . Thus, the holder  20  is moved forward and backward in the horizontal receiving channel  13  of the main body  10  by provision of the two stepped rails  21  and the slideway  22 . 
     In the preferred embodiment of the present invention, the resting portion  32  and the guide bolt  30  are formed integrally. The rotation portion  31  has a center provided with a screw hole  34  screwed onto the guide bolt  30 . The guide bolt  30  has a mediate position provided with an annular groove  33  for mounting a substantially E-shaped snap ring “E”. In assembly, the elastic member “S” is initially mounted on the guide bolt  30 , the guide bolt  30  then extends through the through hole  23  of the holder  20 , the snap ring “E” is then snapped onto the annular groove  33  of the guide bolt  30 , the guide bolt  30  is then screwed through the screw hole  16  of the main body  10 , the screw hole  34  of the rotation portion  31  is then screwed onto the guide bolt  30 , and the rotation portion  31  and the guide bolt  30  are then combined integrally by an adhesive. 
     In operation, referring to  FIGS. 4-8  with reference to  FIGS. 1-3 , when the tube cutter is mounted on a workpiece, such as a tube  50 , the tube  50  is inserted between the two rollers  40  and the cutting wheel  25 , so that the two rollers  40  and the cutting wheel  25  form a three-point contact state to support the tube  50  solidly and stably. At this time, the holder  20  is pressed by the tube  50  to compress the elastic member “S” as shown in  FIG. 4 . Then, the main body  10  and the holder  20  are held by the user&#39;s fingers and are rotated relative to the tube  50 , so that the cutting wheel  25  is revolved on the tube  50  reciprocally so as to shear the tube  50  gradually and successively until the tube  50  is cut as shown in  FIG. 8 . At the same time, the holder  20  is pushed by the elastic force of the elastic member “S”, so that the cutting wheel  25  is fed toward the tube  50  automatically during the cutting process, so as to shear the tube  50  successively. It is appreciated that, the guide bolt  30  is screwed through the screw hole  16  of the main body  10 , and the elastic member “S” is biased between the resting portion  32  of the guide bolt  30  and the holder  20 , so that when the guide bolt  30  is rotated by the rotation portion  31 , the guide bolt  30  is displaced relative to the main body  10 , and the resting portion  32  of the guide bolt  30  is moved forward or backward to compress or loosen the elastic member “S”, so as to regulate the tension of the elastic member “S”. In such a manner, the elastic force of the elastic member “S” is regulated by rotation of the guide bolt  30  so as to correspond to and match the wall thickness of the tube  50 , so that the cutting wheel  25  engages the tube  50  closely and tightly. 
     Accordingly, the holder  20  is pushed by the elastic force of the elastic member “S”, so that the cutting wheel  25  is fed toward the tube  50  automatically during the cutting process, so as to shear the tube  50  successively until the tube  50  is cut, thereby facilitating the user operating the tube cutter to cut the tube  50 . 
     Referring to  FIGS. 9-11 , the rotation portion  31  and the guide bolt  30  are formed integrally. The second end of the guide bolt  30  is provided with an external thread  35  and a pin hole  36 . The resting portion is a nut “N” screwed onto the external thread  35  of the guide bolt  30 , and a pin  37  extends through the pin hole  36  of the guide bolt  30  and rests on the nut “N” to prevent the nut “N” from being detached from the guide bolt  30 . In assembly, the guide bolt  30  is initially screwed through the screw hole  16  of the main body  10 , the snap ring “E” is then snapped onto the annular groove  33  of the guide bolt  30 , the guide bolt  30  then extends through the through hole  23  of the holder  20 , the elastic member “S” is then mounted on the guide bolt  30 , the nut “N” is then screwed onto the external thread  35  of the guide bolt  30 , and the pin  37  then extends through the pin hole  36  of the guide bolt  30  and rests on the nut “N”. 
     Referring to  FIGS. 12-15 , the horizontal portion  11  has a wall corresponding to the vertical portion  12  and provided with a through hole  18 . The guide bolt  30  extends through the through hole  18  of the main body  10  and extends through the through hole  23  of the holder  20 . The guide bolt  30  has a first end provided with a rotation portion  31  protruding from the through hole  18  of the main body  10  and a second end provided with an external thread  35 . The guide bolt  30  is rotated by the rotation portion  31 . A slide  38  is mounted on the guide bolt  30  and received in the horizontal receiving channel  13  of the main body  10 . The slide  38  is provided with an internal thread  39  screwed onto the external thread  35  of the guide bolt  30  so that the slide  38  is moved forward and backward in the horizontal receiving channel  13  of the main body  10  by rotation of the guide bolt  30 . An elastic member “S” is mounted on the guide bolt  30  and is biased between the slide  38  and the holder  20 . 
     In assembly, the guide bolt  30  initially extends through the through hole  18  of the main body  10 , the snap ring “E” is then snapped onto the annular groove  33  of the guide bolt  30 , the guide bolt  30  then extends through the through hole  23  of the holder  20 , the elastic member “S” is then mounted on the guide bolt  30 , and the external thread  35  of the guide bolt  30  is then screwed into the internal thread  39  of the slide  38 , so that the elastic member “S” is biased between the slide  38  and the holder  20 . 
     It is appreciated that, the elastic member “S” is biased between the slide  38  and the holder  20 , so that when the slide  38  is moved forward by a normal rotation of the guide bolt  30 , the elastic member “S” is compressed to have a greater elastic force, and when the slide  38  is moved backward by a reverse rotation of the guide bolt  30 , the elastic member “S” is loosened to have a smaller elastic force. In such a manner, the elastic force of the elastic member “S” is regulated by rotation of the guide bolt  30  so as to correspond to and match the wall thickness of the tube  50 , so that the cutting wheel  25  engages the tube  50  closely and tightly. 
     Referring to  FIGS. 16-19 , a tube cutter in accordance with another preferred embodiment of the present invention comprises a main body  60 , a holder  70 , a guide bolt  80  and two rollers  90 . 
     The main body  60  has a substantially L-shaped profile and includes a horizontal portion  61  and a vertical portion  62 . The main body  60  is provided with a horizontal receiving channel  63  and a vertical receiving channel  64 . The horizontal portion  61  has a wall corresponding to the vertical portion  62  and provided with a through hole  66 . The vertical receiving channel  64  has two sidewalls each provided with two pivot holes  67 . 
     The holder  70  is slidably mounted in the horizontal receiving channel  63  of the main body  60  so that the holder  70  is moved forward and backward in the horizontal receiving channel  63  of the main body  60 . The holder  70  is provided with a receiving space  72 , and a slide  83  is received in the receiving space  72  of the holder  70 . The holder  70  is provided with two positioning holes  73  connected to the receiving space  72 . The holder  70  is provided with two through holes  74  located at two sidewalls of the receiving space  72  and aligning with the through hole  66  of the main body  60 . The holder  70  is provided with a mounting groove  75 , and a cutting wheel  76  is rotatably mounted in the mounting groove  75  and corresponding between the two rollers  90 . The mounting groove  75  has a first sidewall provided with a through bore  77  and a second sidewall provided with a screw bore  78  coaxial with the through bore  77 . The cutting wheel  76  is provided with a shaft bore  79 , and a screw “P” extends through the through bore  77  and the shaft bore  79  and is screwed into the screw bore  78 . 
     The slide  83  is provided with an internal thread  84  and two mounting holes  85 . Two positioning rods  86  extend through the two positioning holes  73  of the holder  70  and the two mounting holes  85  of the slide  83 . Two elastic members “S” are mounted on the two positioning rods  86  and are biased between the slide  83  and the holder  70 . 
     The guide bolt  80  extends through the through hole  66  of the main body  60 , the two through holes  74  of the holder  70  and the internal thread  84  of the slide  83 . The guide bolt  80  has a first end provided with a rotation portion  81  protruding from the through hole  66  of the main body  60  and a second end provided with an external thread  82  screwed through the internal thread  84  of the slide  83 . In assembly, the external thread  82  of the guide bolt  80  initially extends through the through hole  66  of the main body  60  and a front one of the two through holes  74  of the holder  70 , is then screwed through the internal thread  84  of the slide  83 , and then extends through a rear one of the two through holes  74  of the holder  70 . The guide bolt  80  has a mediate position provided with an annular groove  87  for mounting a snap ring  88 . 
     The two rollers  90  are mounted on the main body  60  by two pivot members “Q”. Each of the two rollers  90  is provided with a shaft hole  91 . The two pivot members “Q” extend through the pivot holes  67  of the main body  60  and the shaft holes  91  of the two rollers  90 , so that the two rollers  90  are rotatable freely in the vertical receiving channel  64  of the main body  60 . Each of the two rollers  90  has a periphery provided with a groove  92  to avoid a protruding edge of a tube to be cut. 
     In the preferred embodiment of the present invention, the holder  70  has a side provided with a slideway  71 , the horizontal receiving channel  63  of the main body  60  has a sidewall provided with an aperture  65 , and a positioning pin (not shown) extends through the aperture  65  of the main body  60  and positioned in the slideway  71  of the holder  70 . 
     In operation, referring to  FIGS. 20-22  with reference to  FIGS. 16-19 , when the tube cutter is mounted on a workpiece, such as a tube  100 , the tube  100  is inserted between the two rollers  90  and the cutting wheel  76 , so that the two rollers  90  and the cutting wheel  76  form a three-point contact state to support the tube  100  solidly and stably. At this time, the holder  70  is pressed by the tube  100  to compress the elastic member “S”. Then, the main body  60  and the holder  70  are held by the user&#39;s fingers and are rotated relative to the tube  100 , so that the cutting wheel  76  is revolved on the tube  100  reciprocally so as to shear the tube  100  gradually and successively until the tube  100  is cut as shown in  FIG. 22 . At the same time, the holder  70  is pushed by the elastic force of the elastic member “S”, so that the cutting wheel  76  is fed toward the tube  100  automatically during the cutting process, so as to shear the tube  100  successively. It is appreciated that, when the guide bolt  80  is rotated by the rotation portion  81 , the slide  83  is displaced in the receiving space  72  of the holder  70 , and is moved forward or backward to compress or loosen the elastic member “S”, so as to regulate the tension of the elastic member “S”. In such a manner, the elastic force of the elastic member “S” is regulated by rotation of the guide bolt  80  so as to correspond to and match the wall thickness of the tube  100 , so that the cutting wheel  76  engages the tube  100  closely and tightly. 
     Accordingly, the slide  83  is hidden in the receiving space  72  of the holder  70  to reduce the volume and weight of the tube cutter, thereby facilitating the user carrying the tube cutter. 
     Although the invention has been explained in relation to its preferred embodiment(s) as mentioned above, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the present invention. It is, therefore, contemplated that the appended claim or claims will cover such modifications and variations that fall within the true scope of the invention.