Patent Publication Number: US-2009235791-A1

Title: Suction unit and heat exchange fin manufacturing machine

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a suction unit and a heat exchange fin manufacturing machine, more precisely relates to a suction unit, which is used in a heat exchange fin manufacturing machine cutting a band-shaped metal thin plate to form into heat exchange fins having a prescribed length, each of which has a plurality of collared through-holes, and which feeds the heat exchange fins to a stacking unit, and a heat exchange fin manufacturing machine equipped with the suction unit. 
     A heat exchange fin of a heat exchanger, e.g., air conditioner, is a rectangular metal thin plate, in which a plurality of collared through-holes, into which heat exchange tubes will be inserted, are formed and arranged in the longitudinal direction. The heat exchange fin may be manufactured by, for example, a machine disclosed in Japanese Patent Gazette No. 2002-178065. 
     An outline of the heat exchange fin manufacturing machine is shown in  FIG. 5 . In the machine shown in  FIG. 5 , a band-shaped thin metal plate  100  is extended from a coil thereof and fed to a press unit  104 . In the press unit  104 , a plurality of collared through-holes are formed in the band-shaped metal thin plate  100 , and then the band-shaped metal thin plate  100  is cut and formed into the heat exchange fin having a prescribed length by a cutter  106 . The heat exchange fin is once sucked by a suction unit  108  attached to the press unit  104 , and then accommodated in a stacking unit  110 . 
     As shown in  FIG. 6 , the suction unit  108  has a cylindrical member  114 , in which a sucking section  112  for sucking the heat exchange fin is formed in a bottom face. A perforated plate, in which a number of through-holes are bored, is attached to the sucking section  112 . 
     Further, opening sections  116  are formed in an outer circumferential face of the cylindrical member  114 . Blocking plates  118  are respectively rotatably provided to the opening sections  116 , and the opening sections  116  are closed when end sections of the blocking plates  118  contact edges of the opening sections  116 . The blocking plates  118  are rotated in the same direction by cylinder units (not shown). 
     An exhaust fan  122 , which is driven by a motor  120 , is attached to an upper part of the cylindrical member  114  and connected to an exhaust duct  124 . With this structure, by driving the exhaust fan  122 , air is sucked from the sucking section  112  and the opening sections  116  and discharged outside from an outlet  126  of the exhaust duct  124 . 
     In the suction unit  108  shown in  FIG. 6 , by driving the exhaust fan  122  and actuating the cylinder units (not shown) so as to turn the blocking plates  118  until the end sections of the blocking plates  118  contact the edges of the opening sections  116  as shown in  FIG. 7A , the opening sections  116  are closed. Therefore, air is substantially sucked from the sucking section  112  only, so that the heat exchange fin cut from the band-shaped metal thin plate  100  can be sucked and held by the sucking section  112 . 
     On the other hand, by actuating the cylinder units (not shown) so as to turn the blocking plates  118  and open the opening sections  116  as shown in  FIG. 7B , air can be sucked from the opening sections  116  only so that no air is sucked from the sucking section  112 . Therefore, the heat exchange fin, which has been sucked and held by the sucking section  112 , is released and falls by own weight, so that the heat exchange fin can be accommodated in the stacking unit  110 . 
     These days, a rotational speed of the press unit  104  has been increased so as to increase a manufacturing efficiency of the heat exchange fin manufacturing machine. 
     The manufacturing efficiency of the heat exchange fin must be increased, but speeding up the conventional suction unit  108  is limited. 
     Further, by increasing the manufacturing efficiency of the heat exchange fin, number of making the blocking plate  118  contact with the cylindrical member  114  must be increased, so problems of durability issue and noise occur. 
     SUMMARY OF THE INVENTION 
     The present invention was conceived to solve the above described problems. 
     An object of the present invention is to provide a suction unit, which is capable of solving the problems of the conventional suction unit (i.e., lower speed with respect to a processing speed of the press unit, durability issue, noise), matching an operation speed of the suction unit with processing speeds of the press unit, etc. and improving manufacturing efficiency of a heat exchange fin manufacturing machine. 
     Another object is to provide a heat exchange fin manufacturing machine including the suction unit of the present invention. 
     The inventors have studied to solve the problems and found that it was effective to rotate or swing a blocking plate, by an electric motor, without contacting a cylindrical member of a suction unit, so as to open and close an opening section of the cylindrical member. 
     The inventors have further studied the rotatable or swingable blocking plate and found that an elongated piece cut from a band-shaped metal thin plate could be sucked, toward a sucking section of the cylindrical member, by closing the opening section with the blocking plate when the elongated piece faced the sucking section, and that a heat exchange fin could be released from the sucking section by rotating or swinging the blocking plate until opening the opening section when the elongated piece was cut and formed into the heat exchange fin. 
     Further, by using such a blocking plate, a processing speed of the suction unit could be accelerated, and the problems of durability issue and noise could be solved. 
     To achieve the objects, the present invention has following structures. 
     Namely, the suction unit of the present invention, which is used in a heat exchange fin manufacturing machine cutting a band-shaped metal thin plate to form into heat exchange fins of a prescribed length, each of which has a plurality of collared through-holes, and which feeds the heat exchange fins to a stacking unit, comprises: 
     a cylindrical member having a sucking section, which is opened at a prescribed position, at which an elongated piece formed by cutting the band-shaped metal thin plate can face the sucking section, and which is capable of sucking the elongated piece having faced the sucking section, an opening section being opened at a prescribed position, at which the elongated piece is prohibited to face the opening section, and a suction unit for sucking air from the sucking section and the opening section; 
     a blocking plate being moved, by an electric motor, without contacting the cylindrical member, the blocking plate prohibiting the air suction from the opening section so as to suck the elongated piece by the sucking section when the elongated piece faces the sucking section, the blocking plate allowing the air suction from the opening section so as to feed the heat exchange fin to the stacking unit when the elongated piece sucked by the sucking section is cut and formed into the heat exchange fin having the prescribed length; and 
     a control section controlling the electric motor so as to place the blocking plate at a sucking position when the elongated piece faces the sucking section and at a releasing position when the elongated piece is cut and formed into the heat exchange fin. 
     The heat exchange fin manufacturing machine of the present invention comprises: 
     a press unit forming a plurality of collared through-holes in a band-shaped metal thin plate and cutting the band-shaped metal thin plate to form into heat exchange fins having a prescribed length; 
     a stacking unit stacking the heat exchange fins; and 
     the above described suction unit of the present invention. 
     In the suction unit, the blocking plate may be capable of opening and closing the opening section. With this structure, sucking air from the opening section can be securely performed and stopped. 
     In the suction unit, a plurality of the blocking plates may be provided and synchronously moved. With this structure, sucking the elongated piece by the sucking section and releasing the heat exchange fin therefrom can be rapidly performed. 
     In the suction unit, the blocking plate may be rotated or swung. For example, the rotary blocking plate may be rotated in one direction. In this case, the processing speed of the suction unit can be further accelerated Preferably, the electric motor may be a servo motor. 
     In the suction unit of the present invention, the blocking plate is moved by the electric motor without contacting the cylindrical member, so that the air suction from the opening section is prohibited so as to suck the elongated piece of the metal thin plate by the sucking section when the elongated piece faces the sucking section, and the air suction from the opening section is allowed so as to release the heat exchange fin from the sucking section when the elongated piece sucked by the sucking section is cut and formed into the heat exchange fin. 
     Therefore, the processing speed of the suction unit of the present invention can be higher than that of the conventional suction unit, in which the blocking plate is driven by the cylinder unit, so that processing speeds of the press unit, etc. can be accelerated. 
     Further, the blocking plate is moved without contacting the cylindrical member, so that durability of the blocking plate and the cylindrical member can be improved and the problem of noise can be prevented. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present invention will now be described by way of examples and with reference to the accompanying drawings, in which: 
         FIG. 1  is an explanation view of a heat exchange fin manufacturing machine having the suction unit of the present invention; 
         FIG. 2  is a front view of an embodiment of the suction unit of the present invention; 
         FIG. 3  is an explanation view of a rotary blocking plate used in the suction unit shown in  FIG. 1 ; 
         FIGS. 4A and 4B  are explanation views showing actions of the rotary blocking plate shown in  FIG. 3 ; 
         FIG. 5  is an explanation view of the conventional heat exchange fin manufacturing machine; 
         FIG. 6  is an explanation view of the suction unit used in the conventional heat exchange fin manufacturing machine shown in  FIG. 5 ; and 
         FIGS. 7A and 7B  are explanation views showing actions of the conventional blocking plate shown in  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. 
       FIG. 1  shows an embodiment of a heat exchange fin manufacturing machine having a suction unit of the present invention. In the heat exchange fin manufacturing machine shown in  FIG. 1 , a band-shaped metal thin plate is wound as a coil  11 , and the band-shaped metal thin plate  10  extended from the coil  11  is tensioned and fed to a press unit  12 . In the press unit  12 , a number of collared through-holes are formed in the fed metal thin plate  10  by dies, and then the metal thin plate  10  is cut by a cutter (not shown) of the press unit  12  and formed into a plurality of elongated pieces, each of which has a prescribed width. The elongated pieces are fed to a suction unit  14  in order. When the elongated piece is fed a prescribed length to the suction unit  14 , the fed part of the elongated piece is cut by another cutter (not shown) of the press unit  12  so as to form a heat exchange fin having the prescribed length. 
     The suction unit  14  sucks and holds the elongated piece of the metal thin plate  10 , and the heat exchange fin cut from the elongated piece is released from the suction unit  14  and fed to a stacking unit  18 . A control section controls the suction unit  14  so as to synchronously perform the sucking and releasing actions with actions of the press unit  12 . 
     As shown in  FIG. 2 , the suction unit  14  shown in  FIG. 1  has a cylindrical member  20 , in which a sucking section  22  is formed in a bottom face and opening sections  24  are formed in an outer circumferential face. A perforated plate, in which a number of through-holes are bored, is attached to the sucking section  22  as well as the conventional suction unit  108  shown in  FIG. 6 . 
     An exhaust fan  28 , which is driven by a motor  26 , is attached to an upper part of the cylindrical member  20  and connected to an exhaust duct  30 . With this structure, by driving the exhaust fan  28 , air is sucked from the sucking section  22  and the opening sections  24  and discharged outside from an outlet  32  of the exhaust duct  30 . 
     As shown in  FIG. 3 , rotary blocking plates  34   a,    34   b  and  34   c,  which are respectively attached to shafts  36   a,    36   b  and  36   c  spanned in the cylindrical member  20  and can be rotated in one rotational direction, are provided above the sucking section  22  of the cylindrical member  20 . The rotary blocking plates  34   a,    34   b  and  34   c  are arranged along the sucking section  22 . The rotary blocking plates  34   a,    34   b  and  34   c  can be rotated without contacting not only the adjacent rotary blocking plates but also an inner circumferential face of the cylindrical member  20 . The rotary blocking plates  34   a  and  34   c  are capable of respectively closing the opening sections  24 . 
     Ends of the shafts  36   a,    36   b  and  36   c,  to which the rotary blocking plates  34   a,    34   b  and  34   c  are respectively attached, are outwardly projected form the outer circumferential face of the cylindrical member  20 . As shown in  FIG. 2 , pulleys  38   a,    38   b  and  38   c  are respectively attached to the projected ends of the shafts  36   a,    36   b  and  36   c.    
     A servo motor  40 , which is an example of an electric motor, is provided to the upper part of the cylindrical member  20 , in which the pulleys  38   a,    38   b  and  38   c  are attached. A power of the servo motor  40  is transmitted to the pulley  38   a  by a belt  42   a.  Further, the power transmitted to the pulley  38   a  is transmitted to the pulleys  38   b  and  38   c  by a belt  42   b,  which is engaged with the pulleys  38   a,    38   b  and  38   c.    
     In  FIG. 3 , the pulleys  38   a,    38   b  and  38   c  are synchronously driven by the servo motor  40  and the belts  42   a  and  42   b,  so that the rotary blocking plates  34   a,    34   b  and  34   c  are synchronously rotated in a direction indicated by arrows of by solid lines. 
     Note that, prescribed tension is given to the belt  42   b  engaged with the pulleys  38   a,    38   b  and  38   c  by a tension pulley  44   a,  which is provided between the pulleys  38   a  and  38   b,  and a tension pulley  44   b,  which is provided between the pulleys  38   b  and  38   c.    
     The control section  46  controls the servo motor  40  shown in  FIG. 3  to synchronize with the action of the cutter of the press unit  12  (see  FIG. 1 ), which cuts the elongated pieces to form the heat exchange fins. For example, when the elongated piece  10   a  of the metal thin plate  10  is fed into the sucking section  22  from the press unit  12  as shown in  FIG. 4A , the control section  46  controls the servo motor  40  so as to turn the rotary blocking plates  34   a,    34   b  and  34   c  until they are perpendicularly placed with respect to the sucking section  22  as shown in  FIG. 4A . When the rotary blocking plates  34   a,    34   b  and  34   c  are perpendicularly placed with respect to the sucking section  22  and stopped, air suction from the opening sections  24  is stopped and air can be sucked from the sucking section  22  only. Therefore, the elongated piece  10   a  can be sucked and held by the sucking section  22 . 
     Next, when the elongated piece  10   a  is cut and formed into the heat exchange fin F having the prescribed length by the cutter of the press unit  12  as shown in  FIG. 4B , the control section  46  controls the servo motor  40  so as to turn the rotary blocking plates  34   a,    34   b  and  34   c  until they are paralleled with respect to the sucking section  22 . When the rotary blocking plates  34   a,    34   b  and  34   c  are paralleled with respect to the sucking section  22  and stopped, the air suction from the sucking sections  22  is stopped and air can be sucked from the opening sections  24 . Therefore, the heat exchange fin F sucked and held by the sucking section  22  is released and falls into the stacking unit  18  by own weight. 
     Note that, the heat exchange fin F may be compulsorily released from the sucking section  22 . 
     In the suction unit  14  shown in  FIGS. 2 and 3 , by rotating the rotary blocking plates  34   a,    34   b  and  34   c  by the servo motor  40 , the rotary blocking plates  34   a,    34   b  and  34   c  can be moved between sucking positions, at which the elongated piece  10   a  can be sucked, and releasing positions, at which the heat exchange fin F can be released. 
     With this structure, unlike the blocking plates  118  of the conventional suction unit  108  (see  FIG. 6 ), the rotary blocking plates  34   a,    34   b  and  34   c  can be easily turned and stopped quickly. Therefore, the press unit  12  can be operated at high speed. 
     Further, unlike the conventional suction unit  108  in which the blocking plates  118  contact the inner face of the cylindrical member  114 , the rotary blocking plates  34   a,    34   b  and  34   c  can be rotated without contacting not only the adjacent rotary blocking plates but also the inner circumferential face of the cylindrical member  20 . Therefore, the problems of the conventional suction unit  108  (i.e., durability, noise) can be solved. 
     When the opening sections  24  are closed by the rotary blocking plates  34   a  and  34   c  as shown in  FIG. 4A , small gaps are formed between the rotary blocking plates  34   a  and  34   c  and inner faces of the opening sections  24 . On the other hand, when the air suction from the sucking sections  22  is stopped by the rotary blocking plates  34   a,    34   b  and  34   c  as shown in  FIG. 4B , small gaps are formed between the rotary blocking plates  34   a,    34   b  and  34   c.    
     However, air leakage from the gaps shown in  FIGS. 4A and 4B  is much smaller than an amount of air discharged by the exhaust fan  28 , so no problems occurs. 
     In the suction unit  14  shown in  FIGS. 1-4B , three rotary blocking plates  34   a,    34   b  and  34   c  are provided, but two rotary blocking plates  34   a  and  34   c,  which are capable of closing the opening sections  24 , may be provided. 
     Further, three blocking plates, which can be swung in the same direction indicated by arrows of dotted lines, may be used instead of the rotary blocking plates  34   a,    34   b  and  34   c.  In this case, three swingable blocking plates may be swung by changing the rotational direction of the servo motor  40 . The change of the rotational direction of the servo motor  40  can be controlled by the control section  46 . 
     The invention may be embodied in other specific forms without departing from the spirit of essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.