Abstract:
A parts supply apparatus for moving individual electric parts from a bulk supply of electric parts to an outlet where a part mounting apparatus picks each part up. A parts guide path is located below the bulk supply so that the parts are moved therethrough by force of their own weight. The center of gravity of the parts supply apparatus is preferably located relatively far away from the outlet, so that vibration of the bulk supply of parts to move them into the parts guide path does not cause significant vibration of the outlet and interference with a secure mounting of the parts onto a part mounting apparatus.

Description:
BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT 
     The present invention relates to a parts feeder for supplying each of electric parts from the electric parts in bulk toward an electric part mounting apparatus. 
     JP-A-8-222889 discloses an electronic parts supply device in which a receiving volume receiving electronic parts in bulk is substantially symmetrical relative to a parts guide path through which each of the electronic parts is moved from the receiving volume toward an electric part mounting apparatus. 
     OBJECT AND SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a parts feeder for supplying each of electric parts from the electric parts in bulk toward an outlet thereof at which the each of electric parts is taken by a mounting head of an electric part mounting apparatus for mounting the each of electric parts onto an electric circuit substrate, in which parts feeder the each of the electric parts moves stably and smoothly from the electric parts in bulk toward the outlet. 
     According to the present invention, a parts feeder for supplying each of electric parts from the electric parts in bulk toward an outlet thereof at which the each of electric parts is taken by a mounting head of an electric part mounting apparatus, comprises, a container having a receiving volume adapted to receive therein the electric parts in bulk, and a parts guide path extending from the receiving volume so that the each of electric parts is moved therethrough toward the outlet by a gravity of the each of electric parts, wherein a horizontal position of the parts guide path is arranged between a horizontal position of the center of gravity G as showen in FIG. 1 of the parts feeder and a horizontal position of the outlet as seen in a direction perpendicular to a horizontal direction passing the parts guide path and the outlet. 
     More particularly, with reference to the drawings, the following preferred aspects of the invention will be apparent. The horizontal position of the second parts guide path  30  is arranged between the horizontal position of the center of gravity G of the parts feeder  10  and the horizontal position of the outlet  82  as seen in the direction perpendicular to the horizontal direction  80  passing the parts guide path  30  and the outlet  82 , that is, the horizontal position of the center of gravity G of the parts feeder  10  is arranged far away from the outlet  82  at a relatively outer side of the electric part mounting apparatus and/or the parts guide path, so that the center of gravity G of the parts feeder  10  may be effectively vibrated in accordance with a vibration of the electric part mounting apparatus  100  and/or a horizontal positioning movement of the parts feeder  10 , while restraining a significant vibration of the outlet  82 , so that the electric parts  3  in bulk received in the receiving volume  21  are vibrated effectively to accelerate or cause a smooth and stable movement of each of the electric parts  3  in the receiving volume  21  toward the parts guide path  30  and the outlet  82  without causing significant vibration of the outlet  82  and thereby deteriorating a secure taking of the electric parts  3  by the mounting head. In addition to this, the case  56  may be taken by a single hand from a rear surface  53  of the parts feeder  10 . 
     When the receiving volume  21  has a first horizontally terminating end  84  and a second horizontally terminating end  86  along the horizontal direction: (a) a horizontal position of the first horizontally terminating end  84  is arranged between the horizontal position of the parts guide path  30  and the horizontal position of the outlet  82  as seen in the direction; (b) the horizontal position of the parts guide path  30  is arranged between the horizontal position of the first horizontally terminating end  84  and a horizontal position of the second horizontally terminating end  86  as seen in the direction; and (c) a horizontal distance between the horizontal position of the parts guide path  30  and the horizontal position of the second horizontally terminating end  86  along the horizontal direction  80  is larger than the horizontal distance between the horizontal position of the parts guide path  30  and the horizontal position of the first horizontally terminating end  84  along the horizontal direction. The center of gravity G of the parts feeder  10 , or particularly a main part of the electric parts  3  in bulk in the receiving volume  21  is arranged securely far away from the outlet  82  at the relatively outer side of the electric part mounting apparatus in comparison with the parts guide path, so that the main part of the electric parts  3  in bulk received in the receiving volume  21  can be vibrated effectively while restraining significant vibration of the outlet  82 . 
     To effectively arrange the center of gravity G of the parts feeder  10  far away from the outlet  82  at the relatively outer side of the electric part mounting apparatus in comparison with the parts guide path, the parts feeder  10  should comprise: (a) at least one of a vibration generating motor for generating a force to cause a relative vibration between the parts guide path  30  and each of the electric parts  3 ; (b) a pneumatic unit  40  for generating a pneumatic pressure to urge each of the electric parts  3  toward the outlet  82  after each of the electric parts  3  is moved through the parts guide path  30  toward the outlet  82  by the gravity of each of the electric parts  3 ; and (c) a toggle joint  50  for releasably fixing the parts feeder  10  to a movable table  70  of the electric part mounting apparatus  100 . Also, the horizontal position of the parts guide path  30  should be arranged between at least one of a, b and c and the horizontal position of the outlet  82  as seen in the direction. 
     When the receiving volume  21  has a first upper end  88  and a second upper end  90 , and a vertical position of the first upper end  88  is lower than a vertical position of the second upper end  90 , then: (a) the horizontal position of the first upper end  88  is arranged between the horizontal position of the parts guide path  30  and the horizontal position of the outlet  82  as seen in the direction, and; (b) the horizontal position of the parts guide path  30  is arranged between the horizontal position of the first upper end  88  and a horizontal position of the second upper end  90  as seen in the direction; and (c) the main part of the electric parts  3  in bulk in the receiving volume  21  is arranged securely far away from the outlet  82  at the relatively outer side of the electric part mounting apparatus in comparison with the parts guide path, so that the main part of the electric parts  3  in bulk received in the receiving volume  21  is vibrated effectively while restraining significant vibration of the outlet  82 . 
     When the second upper end (surface)  90  has a cover  24  openable for inserting therethrough the electric parts  3  into the receiving volume  21 , the main part of the electric parts  3  in bulk received in or supplied into the receiving volume  21  is easily arranged far away from the outlet  82 . The receiving volume  21  has preferably joint surfaces inclined relative to the horizontal direction  80  extending between the first upper end  88  and the second upper end  90 . 
     When the receiving volume  21  has a first lower surface  92  inclined relative to the horizontal direction  80  and extending from the parts guide path  30  and a second lower surface  94  inclined relative to the horizontal direction  80  and extending from the parts guide path  30 , then: (a) a horizontal position of the first lower surface  90  is arranged between the horizontal position of the parts guide path  30  and the horizontal position of the outlet  82  as seen in the direction; (b) the horizontal position of the parts guide path  30  is arranged between the horizontal position of the first lower surface  92  and a horizontal position of the second lower surface  94  as seen in the direction; and (c) a vertical position of an upper terminating end  96  of the second lower surface  94  is higher than a vertical position of an upper terminating end  98  of the first lower surface  92 ; and (d) each of the electric parts  3  at an upper end of the parts guide path  30  is urged more strongly into the parts guide path  30  by the portion of the electric parts  3  in bulk over the second lower surface  94  rather than the portion of the electric parts  3  in bulk over the first lower surface  92 . Therefore, each of the electric parts  3  at the upper end of the parts guide path  30  is securely and smoothly introduced into the parts guide path  30  by the portion of the electric parts  3  in bulk over the second lower surface  94 , which restrains significant vibration of the outlet  82  by keeping a main part of the electric parts  3  in the receiving volume  21  far away from the outlet  82 . 
     When the parts feeder further comprises a mounting surface inclined relative to the horizontal direction to form an acute angle between the mounting surface and the horizontal direction, the horizontal position of the parts guide path is arranged between a horizontal position of the mounting surface and the horizontal position of the outlet as seen in the direction, and the mounting surface includes a holder adapted to hold a case for receiving the electric parts supplied into the receiving volume, the center of gravity of the parts feeder is arranged securely far away from the outlet at the relatively outer side of the electric part mounting apparatus in comparison with the parts guide path. 
     When the parts feeder further comprises a part detector for detecting the each of electric parts moving through the parts guide path, and a light emitter for emitting a light in response to each detection of the part detector, and the parts guide path is arranged between the light emitter and the outlet as seen in the direction, the light indicating a stable feed of the each of electric parts through the parts guide path is easily and securely visible for an operator of the electric part mounting apparatus. 
     When the receiving volume has a first upper end surface and a second upper end surface, a vertical position of the first upper end surface is lower than a vertical position of the second upper end surface, and the parts guide path is arranged below the first upper end, an inlet or upper end of the parts guide path is prevented or restrained from being pressed strongly by the electric parts on and over the parts guide path. Therefore, the electric parts is smoothly introduced into the parts guide path, and the electric parts is prevented or restrained from being damaged by each other and/or the inlet or upper end of the parts guide path when the electric parts is introduced into the parts guide path. The first upper end surface may include a joint surface inclined relative to the horizontal direction to extend upward toward the second upper end surface. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a partially cross-sectional view showing a bulk-parts feeder of the present invention. 
     FIG. 2 is a partially cross-sectional and enlarged view showing a parts container forming a receiving volume for receiving electric parts therein, of the present invention. 
     FIG. 3 is a cross-sectional view showing the parts container of the present invention. 
     FIG. 4 is a block diagram showing an electric circuit for the bulk-parts feeder. 
     FIG. 5 is a cross-sectional view showing another embodiment of the parts container of the present invention. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     As shown in FIG. 1, a bulk-parts feeder  10  has a long-plate-shaped base  11 , a container  20  including a receiving volume  21  for receiving electric parts  3  in bulk therein, a first parts passage member  12  mounted on the base  11  and including a horizontally extending first parts guide path  13  covered by a cover plate  14 , a mount body  15  attached to a lower surface of the base and detachably attached to a table  71  of a movable table  70  so that the bulk-parts feeder  10  is driven to be positioned with a high-moving speed in a movable table longitudinal direction (a direction perpendicular to this drawing paper) by the movable table  70 , a block  16  on the base  11 , and a frame  17  through which the container  20  is mounted onto the base  11 . 
     As shown in FIGS. 2 and 3, the container  20  has a front upper surface  22   b , a rear upper surface  22   a  significantly higher than the front upper surface  22   b , and an inclined joint surface  23  between the front upper surface  22   b  and the rear upper surface  22   a . The rear upper surface  22   a  includes an openable cover  24  through which the electric parts in bulk are supplied into the receiving volume  21  and are taken out of the receiving volume  21 . Since the openable cover  24  is arranged at a relatively higher position of the bulk-parts feeder  10 , an operator of the bulk-parts feeder  10  can easily supplies the electric parts  3  into the receiving volume  21  through the openable cover  24  from a rear side of the movable table  70 , and a rigidity of the container  20  is increased so that an undesirable deformation of the container  20  positioned with the high moving speed by the movable table  20  is restrained. 
     A cone-shaped inlet portion  25  for a second parts guide path  30  is arranged at a lower front portion of the receiving volume  21 . The second parts guide path  30  communicating with the first parts guide path  13  is formed by an inner cylindrical surface of an inner fixed tube  31 , and the tube  31  is surrounded by an outer tube  32  rotatable and movable up and down. 
     The outer tube  32  has flanges  33  between which an eccentric pin  35  rotating eccentrically by a motor  34  is received. The eccentric pin  35  contacts frictionally an O-ring  36  attached to a lower surface of upper one of the flanges  33 . The motor  34  is mounted on the container  20  through a support frame  37 . 
     When the motor  34  drives the eccentric pin  35  eccentrically, the outer tube  32  is rotated and moved by the eccentric pin  35  up and down, so that an upper end of the outer tube  32  vibrates the electric parts in the inlet portion  25  to accelerate a drop of the each of the electric parts into the second parts guide path  30 . The each of the electric parts dropped into the second parts guide path  30  moves through the first parts guide path  13  to an outlet at which the each of the electric parts is taken by an electric parts mounting apparatus&#39;s mounting head  46 . An openable shutter  42  is arranged over the outlet. 
     A horizontal length L 1  of a rear side of the receiving volume  21  from the second parts guide path  30  is significantly larger than a horizontal length L 2  of a front side thereof, so that a center of gravity g of the container  20  is arranged on the rear side thereof far away from the outlet. 
     A pneumatic unit  40  is arranged at the rear side to supply a positive pressure into the first parts guide path  13  from a rear end of the first parts guide path  13  or a negative pressure thereinto from a front end thereof through a fluidal pipe  41  to transfer the each of the electric parts  3  to the outlet. 
     Referring again to FIG. 1, the openable shutter  42  over the outlet is operated by a lever  43  with a roller  44  so that the each of the electric parts  3  reaching the outlet is exposed to be taken by a vacuum nozzle  47  of the mounting head  46  when the outlet of the bulk-parts feeder  10  is positioned correctly relative to the mounting head  46  by the movable table  70  and the roller  44  is pressed by a pressing pad  45  of the electric parts mounting apparatus. 
     The first parts guide path  13  passes through an electric part detector  48  at a rear portion of the first parts guide path  13 , and a bar-shaped holder  60  is swingable up and down on a mounter  62  at a back surface of a rear frame  49  of the bulk-parts feeder  10 . A light emitter  61  is arranged at a terminating end of the holder  60 . A projection  63  extends from the holder  60  into the rear frame  49  to be connected to an electric source switch  64 . When the holder  60  is oriented upward as shown in a solid line so that the light emitter  61  is easily visible from a rear side of the bulk-parts feeder  10 , the projection  63  presses a lever  65  of the electric source switch  64  to close the electric power source switch  64 , and when the holder  60  is oriented downward as shown in a dot line, the projection  63  is separated from the lever  65  to open the electric power source switch  64 . As shown in FIG. 4, the motor  34 , the electric part detector  48  and the light emitter  61  are connected to a controller  66  which is connected to an electric power source  67  through the electric power source switch  64 . 
     When the electric part detector  48  detects a feed of the each of the electric parts  3  in the first parts guide path  13 , the light emitter  6  emits a light, so that the operator can recognize a non-trouble feed of the each of the electric parts  3  in the first parts guide path  13 . When the bulk-parts feeder  10  is set on the table  71  with gripping a holding portion  58 , and the holder  60  is moved by a hand simultaneously with gripping the holding portion  58  by the hand to be oriented upward, the bulk-parts feeder  10  is ready for being operated. 
     A hook  51  extends from a toggle  50  arranged at a rear side of the base  11 , and an operating lever  52  extends upward from the toggle  50 . When the operating lever  52  is swung to a direction denoted by an arrow A, the hook  51  swings forward and backward to engage with an engage port  72  of the table  71  and disengage therefrom so that the bulk-parts feeder  10  is fixed to the table  71  and is detached therefrom. 
     The rear frame  49  has an inclined rear surface  53  forming an acute angle  102  relative to a horizontal direction  80  and facing to the ground, a bracket  54  on the inclined rear surface  53 , and a case holder  55  on the bracket  54 . An electric parts case  56  is detachably mounted onto the case holder  55  after the operator supplies the electric parts into the receiving volume  21  from the electric parts case  56  in response to that a lack of the electric parts in the receiving volume  21  occurs. The electric parts case  56  has a label indicating a sort of the electric parts to be received therein so that the operator can recognize the sort of the electric parts in the receiving volume  21 . Since the rear surface  53  is inclined relative to the horizontal direction  80  and faces to the ground, a space under the rear surface  53  can receive the electric parts case  56  to restrain a horizontal backward extension of the bulk-parts feeder  10  by the electric parts case  56 .