Abstract:
There is provided a working machine including a guide beam having a power transmitter; at least one working head comprising a power receiver and configured to move along the guide beam, wherein the power receiver receives power from the power transmitter in a non-contact manner in which the power receiver and the power transmitter are not physically connected, and wherein the working head operates by the received power in the non-contact manner.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS 
     This application claims priority from Japanese Patent Application No. 2012-140139, filed on Jun. 21, 2012, in the Japanese Patent Office, and Korean Patent Application No. 10-2012-0110091, filed on Oct. 4, 2012, in the Korean Intellectual Property Office, the disclosures of which are incorporated herein by reference in their entireties. 
     BACKGROUND 
     1. Field 
     Apparatuses consistent with exemplary embodiments relate to a working machine including a working head moving along a guide beam. 
     2. Description of the Related Art 
     An electronic component mounting apparatus for mounting an electronic component, such as an integrated circuit (IC) chip, on a printed circuit board is an example of a working machine that includes a working head moving along a guide beam.  FIG. 1  illustrates an electronic component mounting apparatus of the related art which includes a mounting head  100  as a working head, where the mounting head  100  includes a nozzle. The mounting head  100  is movable in an X-direction along a guide beam, referred to as an X-direction beam  200 . The X-direction beam  200  straddles over a pair of Y-direction beams  300  that are spaced apart from each other in the X-direction and the X-direction beam is installed on the Y-direction beams  300 . The X-direction beam is movable in the Y-direction along the Y-direction beams  300 . As such, the mounting head  100  may freely move in the X-direction and the Y-direction within a horizontal plane according to a combination of the X-direction beam  200  and the Y-direction beam  300 . According to a combined movement in the X-direction and the Y-direction, the mounting head  100  moves to a component supply unit (not shown), picks up an electronic component from the component supply unit by using a nozzle, moves to a predetermined mounting location of a printed circuit board (not shown), and then mounts the electronic component at the predetermined mounting location of the printed board. 
     In order to drive the electronic component mounting apparatus, power needs to be supplied to the mounting head  100  or the like. In the related art, for example, in Japanese Patent Publication JP 2008-243839, power is supplied to the mounting head  100  from an external power source by using a cable, and a Cableveyor™  210  is used to move a direct power feeder, such as a cable or a slip ring, within range of the mounting head  100  in the X-direction. 
     However, abrasion or disconnection is not completely prevented by using such a power supply method, and when the Cableveyor™ is installed to provide power to a mounting head  100 , operational range of the mounting head in an X-Y direction is limited. Thus, even when a plurality of mounting heads are mounted on one X-direction beam to improve mounting efficiency, operational range of each mounting head is not sufficiently obtained, and it is difficult in practice to install the plurality of mounting heads on one X-direction beam. 
     Such power supply problems are not limited to the electronic component mounting apparatus and are common to a working machine that includes a working head moving along a guide beam. 
     SUMMARY 
     One or more exemplary embodiments provide a working machine powered in a non-contact manner including a working head moving along a guide beam, wherein power is supplied to the working head without using a direct power feeder. 
     According to an aspect of an exemplary embodiment, there is provided a working machine including a guide beam including a power transmitter; at least one working head comprising a power receiver which moves along the guide beam, wherein the power receiver receives power from the power transmitter in a non-contact manner in which the power receiver and the power transmitter are not physically connected, and wherein the working head operates by the received power in the non-contact manner. 
     The working head may move in a direction along an extension direction of the guide beam and maintains a uniform distance from the guide beam in a direction perpendicular from the extension direction. 
     The non-contact manner includes electric field coupling, wherein the power transmitter comprises a power transmitter electrode, and wherein the power receiver comprises a power receiver electrode facing the power transmitter electrode. The power receiver electrode maintains a uniform distance from the power transmitter electrode in a direction perpendicular to an extension direction of the guide beam. 
     The non-contact manner may include electromagnetic induction, wherein the power transmitter comprises a power transmitter coil, and wherein the power receiver comprises a power reception coil facing the power transmitter coil. 
     The power reception coil may maintain a uniform distance from the power transmitter coil in a direction perpendicular to an extension direction of the guide beam. 
     The at least one working head may include a plurality of the working heads which move along the same guide beam. 
     The working head may include a wireless communication unit configured to receive a control signal to operate the working head, and at least one pressure generating unit. 
     According to an aspect of another exemplary embodiment, there is provided a working machine including a power transmitter disposed on a guide beam; a power receiver disposed on a working head, wherein the working head moves along the guide beam maintaining a uniform distance between the power transmitter and the power receiver, wherein the power transmitter transmits power to the power receiver wirelessly, and the working head operates by the transmitted power. 
     According to an aspect of another exemplary embodiment, there is provided a component moving apparatus including: a guide beam comprising a power transmitter; at least one working head comprising a power receiver and configured to move along the guide beam; wherein the power receiver receives power from the power transmitter in a non-contact manner in which the power receiver and the power transmitter are not physically connected, and wherein the working head operates by the received power in the non-contact manner. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and/or other aspects will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which: 
         FIG. 1  is a diagram illustrating a structure of a electronic component mounting apparatus of the related art; 
         FIG. 2  is a diagram illustrating a basic structure of an electronic component mounting apparatus in a view along a Y-direction according to an exemplary embodiment; 
         FIG. 3  is a side view along an X-direction illustrating a structure for supplying power to a mounting head in the electronic component mounting apparatus of  FIG. 2  according to an exemplary embodiment; 
         FIG. 4  is a circuit diagram equivalent to the structure of  FIG. 3 ; 
         FIG. 5  is a side view illustrating a structure for supplying power to the mounting head in the electronic component mounting apparatus of  FIG. 2  according to another exemplary embodiment; 
         FIG. 6  is a cross-sectional view of a positive pressure generating unit according to an exemplary embodiment; and 
         FIG. 7  is a cross-sectional view of a negative pressure generating unit according to an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, one or more embodiments will be described in detail with reference to accompanying drawings. Also, in drawings, same reference numerals denote same elements to avoid repetition. An example of a working machine according to an exemplary embodiment will now be described, specifically, an electronic component mounting apparatus. 
       FIG. 2  is a diagram illustrating a basic structure of an electronic component mounting apparatus  1  according to an exemplary embodiment. The electronic component mounting apparatus  1  includes a mounting head  10  as a working head. The mounting head  10  picks up an electronic component and mounts the electronic component onto a printed circuit board. One or more nozzles  11  are installed onto the mounting head  10  and are movable in a Z-direction crossing X- and Y-directions, i.e., in an up-and-down direction as shown in  FIG. 2 . 
     Referring to the electronic component mounting apparatus  1  of  FIG. 2 , three mounting heads  10  are installed to an X-direction beam  20  and are movable in an X-direction along the X-direction beam  20 . Each of the three mounting heads  10  may be a rotary type or linear type inclusive of a plurality of nozzles, a type including one nozzle, or a combination of a plurality of mounting head types. Each of the three mounting heads  10  may be of the same or different type and may move freely according to an optimized program while avoiding collision and interference from one another. The X-direction beam  20  is an example of a guide beam according to an exemplary embodiment. 
     In  FIG. 2 , only one X-direction beam  20  is shown, but alternatively, a pair of the X-direction beams  20  may straddle over the Y-direction beams  30  as shown in  FIG. 1 , and one or more mounting heads  10  may be installed to one of the X-direction beams  20 . 
     The X-direction beam  20  straddles over a pair of Y-direction beams  30  that are spaced apart from each other in the X-direction and the X-direction beam  20  is installed on the Y-direction beams  30 . The X-direction beam is movable in the Y-direction along the Y-direction beams  30 . As such, one or more of the three mounting heads  10  freely moves in the X-direction and the Y-direction within a horizontal plane according to a combination of the X-direction beam  20  and the Y-direction beam  30 . According to a combined movement in the X-direction and the Y-direction, one or more of the three mounting heads  10  moves to a component supply unit (not shown), picks up an electronic component by using a nozzle  11 , moves to a predetermined mounting location of a printed circuit board (not shown), and then mounts the electronic component at the predetermined mounting location of the printed circuit board. 
       FIG. 3  is a diagram illustrating a structure for supplying power to the mounting head  10  according to an exemplary embodiment. As shown in  FIG. 3 , the mounting head  10  is installed to the X-direction beam  20  along a length direction (X-direction) of the X-direction beam  20  by using a linear guide  13  installed to a board plate  12 , and is movable in the X-direction. In other words, the mounting head  10  freely moves in the X-direction while maintaining a uniform distance from the X-direction beam  20 . 
     In  FIG. 3 , electric field coupling is used to supply power to the mounting head  10 . According to the electric field coupling, power is transmitted in a non-contact (wireless) manner by using an electric field generated when a power transmitter electrode and a power receiver electrode approach each other, wherein the power transmitter electrode is installed to a power transmission side and the power receiver electrode is installed to a power reception side. 
     In  FIGS. 3 and 4 , the X-direction beam  20  is the power transmission side, and the mounting head  10  is the power reception side. That is, a power transmitter is installed to the X-direction beam  20  and a power receiver is installed to the mounting head  10 . A power transmitter electrode  21  is installed to the power transmitter installed to the X-direction beam  20  and a power receiver electrode  14  is installed to the mounting head  10 . Power transmitter electrode  21  is installed to protrude vertically (in a Z-direction as shown in  FIG. 3 ) from top and bottom surfaces of the X-direction beam  20 , and the power receiver electrode  14  is installed to protrude vertically (in the Z-direction as shown in  FIG. 3 ) from top and bottom surfaces of the board plate  12  of the mounting head  10  so as to face the power transmitter electrode  21  in a Y-direction as shown in  FIG. 3 . An equivalent circuit of the power transmission system of  FIG. 3  is shown in  FIG. 4 . Referring to  FIG. 3  and  FIG. 4 , in order to drive mounting head  10 , power is transmitted from the power transmitter to the power receiver according to the electric field coupling between the power transmitter electrode  21  and the power receiver electrode  14 . 
       FIG. 4  illustrates capacitance C 1  and C 2  formed between the power transmitter electrode  21  of the X-direction beam  20  and the power receiver electrode  14  of the mounting head  10 . The X-direction beam  20  includes a power transmitter, a pair of inductors L 1  and L 2  along with a power source V and impedance Z 0 . One the other hand, the mounting head  10  includes the power receiver and impedance Z 1 . 
     Since the mounting head  10  moves in the X-direction while always maintaining a uniform distance from the X-direction beam  20  as described above, a distance between the power transmitter electrode  21  and the power receiver electrode  14  is always constant and may be easily kept to be a minimal distance. The constant and minimal distance may be suitable for transmitting power by using the electric field coupling. 
       FIG. 5  is a diagram illustrating a structure for supplying power to the mounting head  10 , according to another exemplary embodiment. In  FIG. 5 , electromagnetic induction is used to supply power to the mounting head  10 . A power transmission coil is installed to a power transmission side and a power reception coil is installed to a power reception side, and power is transmitted in a non-contact (wireless) manner via electromagnetic induction. 
     In  FIG. 5 , the mounting head  10  is installed to the X-direction beam  20  along the length direction (X-direction) by using the linear guide  13  installed to the board plate  12 , and is movable in an X-direction along X-direction beam  20 . 
     In  FIG. 5 , a power supply rail  22  is installed along the length direction of the X-direction beam  20 , as a power transmitter. Power is supplied to the power supply rail  22 , and a roller  15  moves in the X-direction in synch with movement of the board plate  12 . As roller  15  moves in the X-direction, roller  15  is rotated while maintaining electrical contact with the power supply rail  22 . A power transmission coil  16  is installed to the roller  15 , and a power reception coil  17  is disposed at a location facing the power transmission coil  16 . The power reception coil  17  is installed to the board plate  12  of the mounting head  10 , and power generated via electromagnetic induction with the power transmission coil  16  is supplied to the mounting head  10 . 
     As shown in  FIG. 3  and  FIG. 5 , a power transmitter (the power transmitter electrode  21  and the power supply rail  22 ) is installed to the X-direction beam  20 . A power receiver (the power receiver electrode  14  and the power reception coil  17 ) that receives power in a non-contact (wireless) manner from the power transmitter is installed to the mounting head  10 , and the power received is used to drive the mounting head  10 . Power may thus be supplied to the mounting head  10  without having to install a direct power feeder. 
     In addition to power, vacuum suction and compressed air need to be supplied to the mounting head  10  in order to pick up an electronic component and then mount the electronic component on a printed circuit board. In other words, the nozzle  11  of the mounting head  10  uses vacuum suction to pick up the electronic component, and a small amount of compressed air is blown to break the vacuum suction so that the electronic component may be mounted. In an electronic component mounting apparatus of the related art, a negative pressure generating unit for supplying the vacuum suction and a positive pressure generating unit for supplying the compressed air are generally installed external to the mounting head  10 , and the positive pressure generating unit and the negative pressure generating unit are each connected to the mounting head  10  through an air pipe. 
     Similarly, a supplied signal is required to control the mounting head  10 . The signal may be supplied via wires in the related art electronic component mounting apparatus, and a control unit and the mounting head  10  are connected via a signal cable. Like a power supply cable, the air pipe and the signal cable are connected to the mounting head  10  by using the Cableveyor™  210  of  FIG. 1 . Accordingly, the air pipe and the signal cable should be removed so as not to use the Cableveyor™  210 . 
     The signal cable may be removed by installing a wireless communication unit in the mounting head  10 . Wireless communication is a well known technology, and thus details thereof are not described herein. 
     The air pipe may be removed by installing a positive pressure generating unit and a negative pressure generating unit inside the mounting head  10 . 
     The positive pressure generating unit may be a micro blower  40  shown in  FIG. 6 . The micro blower  40  of  FIG. 6  includes a vibration plate  41  formed of a flexible film or a flexible thin plate, a piezoelectric element  42  installed to the vibration plate  41 , and a structure  43  forming an air chamber  43   a  and an air inflow chamber  43   b  with the vibration plate  41 . 
     When the vibration plate  41  is vibrated by the piezoelectric element  42 , air in the air inflow chamber  43   b  is discharged from a discharge unit  43   c  of the structure  43 , with and by air being due to continuously discharged air from the air chamber  43   a . By supplying the air discharged from the discharge unit  43   c  to each nozzle  11  of the mounting head  10 , vacuum suction of the nozzle  11  may be broken. 
     Meanwhile, the negative pressure generating unit may be formed by using the micro blower  40  described above. An exemplary embodiment of the micro blower  40  is shown in  FIG. 7 . A negative pressure generating unit  50  shown in  FIG. 7  includes a straight main conduit  51  and a branch conduit  52 . One end of the straight main conduit  51  is connected to the discharge unit  43   c  of the micro blower  40  of  FIG. 6 , and the other end is open to air. The branch conduit  52  branches from the straight main conduit  51  at a right angle and is connected to each nozzle  11  of the mounting head  10 . When air that is discharged from the micro blower  40  moves inside the straight main conduit  51 , pressure formed inside of the straight main conduit  51  turns negative according to flow speed of the air, and thus pressure inside the branch conduit  52  turns negative. Accordingly, it is possible to supply negative pressure to the nozzle  11 . 
     The micro blower  40  of the current exemplary embodiment has dimensions of 20 mm in length, 20 mm in width, and 2 mm in thickness (when excluding the discharge unit  43   c ). Thus, the micro blower  40  can be installed inside of the mounting head  10 . The small size of micro blower  40 , having air discharge pressure of about 1900 Pa and air volume of about 1 L per minute, allows the micro blower  40  to operate as both the positive pressure generating unit and the negative pressure generating unit in the current exemplary embodiment. 
     As described above, using a non-contact (wireless) power feeder removes the need for a Cableveyor™  210  when installing the plurality of mounting heads  10  on the X-direction beam  20  as shown in  FIG. 2 . 
     The exemplary embodiment is not limited to an electronic component mounting apparatus  1  and may be applied to any working machine inclusive of a working head moving along a guide beam, such as, for example, a welding apparatus inclusive of a welding head moving along a guide beam. 
     According to one or more exemplary embodiments, since power is transmitted in a non-contact manner, power may be supplied to the working head without abrasion or disconnection. In the case of a plurality of working heads mounted on one guide beam, power feeders will not interfere with one another. 
     While exemplary embodiments have been particularly shown and described above, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the inventive concept as defined by the following claims.