Patent Grant
6948232
This application is a National Stage of International Application No. PCT/JP00/05909, filed Aug. 31, 2000.
The present invention relates particularly to a component recognizing method and apparatus for recognizing components prior to installation of the components onto objects to be installed, such as boards and components, and to a component mounting method and apparatus for installing recognized components onto the objects, such as boards and components, in component mounting equipment for mounting components such as electronic components and optical components.
As a head unit having suction nozzles for sucking and holding components in such a component mounting apparatus, for example, such a head unit 700 as shown in
Such a head unit 770 as shown in
Hereinbelow, configurations of the head units 700 and 770 will be described.
In
Hereinbelow, movement of the head unit 700 configured as above will be described. In
At commencement of recognition in
In practice, as shown in
The configuration of the head unit 770 shown in
Reference numeral 771 denotes a frame that serves as a foundation of the head unit 770, and the frame 771 is integral with motors 772, 773, and 774 which are drive sources. Numerals 775, 776, and 777 denote ball screws which are rotated individually by the motors 772, 773, and 774, respectively, and numerals 778, 779, and 780 denote nozzles for holding components. Rotational drive caused by the motors 772, 773, and 774 is transmitted to the nozzles 778, 779, and 780 through a medium of the ball screws 775, 776, and 777 so as to move the nozzles vertically. As a result, settings of vertical movements of the nozzles 778, 779, and 780 can be individually provided by the motors 772, 773, and 774.
Hereinbelow, movement of the head unit 770 configured as above will be described.
In
On the other hand, such a configuration of the head unit 700 as mentioned above with reference to
In recent years, however, a need for mounting of various types of components has increased and component mounting apparatus which are capable of recognizing various components continuously have been essential for board mounting with high efficiency.
With such a configuration of the head unit 770 as mentioned above with reference to
It is an object of the present invention to solve the above-mentioned issues; that is, to provide a component recognizing method and apparatus, and component mounting method and apparatus by which components with various heights held by a plurality of component holding members can be recognized continuously.
In order to achieve the above-mentioned object, the present invention is configured as will be described below.
According to a first aspect of the present invention, there is provided a component recognizing method for recognizing, via one recognition unit, surfaces to be recognized of a plurality of components held by a plurality of component holding members which are vertically moved selectively by a single drive unit, with the surfaces to be recognized being at different heights, in which heights of the component holding members are controlled so as to bring a surface to be recognized of each of the plurality of components into a recognizable range of the recognition unit, and the surfaces to be recognized of the plurality of components are continuously recognized.
According to a second aspect of the present invention, there is provided a component recognizing method as defined in the first aspect, wherein the plurality of components held by the plurality of component holding members, and having the surfaces to be recognized at different heights, have such a variation in height that not all the surfaces to be recognized of the plurality of components are within the recognizable range of the recognition unit when bottom end surfaces of the plurality of component holding members are situated at an identical height.
According to a third aspect of the present invention, there is provided a component recognizing method as defined in the second aspect, wherein, from among the plurality of components held by the plurality of component holding members and having the surfaces to be recognized at different heights, which components have such a variation in height that not all the surface to be recognized of the plurality of components are within the recognizable range of the recognition unit when the bottom end surfaces of the plurality of component holding members are situated at an identical height, components of which the surfaces to be recognized are within the recognizable range of the recognition unit are recognized without a selective vertical movement of component holding members holding these components by drive of a single drive unit and without a change in heights of the surfaces, and components of which the surfaces to be recognized are out of the recognizable range of the recognition unit are recognized after performing a positioning operation via vertical movement of component holding members holding these components, so as to bring the surfaces to be recognized of these components into the recognizable range of the recognition unit.
According to a fourth aspect of the present invention, there is provided a component recognizing method as defined in any one of the first to third aspects, wherein shapes of the components are recognized when the surfaces to be recognized of the components are recognized.
According to a fifth aspect of the present invention, there is provided a component recognizing apparatus for recognizing, via one recognition unit, surfaces to be recognized of a plurality of components held by a plurality of component holding members which are vertically moved selectively by a single drive unit and having the surfaces to be recognized at different heights, wherein heights of the component holding members are adapted to be controlled so as to bring a surface to be recognized of each of the plurality of components into a recognizable range of the recognition unit and continuously recognizable the surfaces to be recognized of the plurality of components.
According to a sixth aspect of the present invention, there is provided a component recognizing apparatus as defined in the fifth aspect, wherein the plurality of components held by the plurality of component holding members and having the surfaces to be recognized at different heights, have such a variation in height that not all the surface to be recognized of the plurality of components are within the recognizable range of the recognition unit when bottom end surfaces of the plurality of component holding members are situated at an identical height.
According to a seventh aspect of the present invention, there is provided a component recognizing apparatus as defined in the sixth aspect, wherein, from among the plurality of components held by the plurality of component holding members and having the surfaces to be recognized at different heights, which components have such a variation in height that not all the surfaces to be recognized of the plurality of components are within the recognizable range of the recognition unit when the bottom end surfaces of the plurality of component holding members are situated at an identical height, components of which the surfaces to be recognized are within the recognizable range of the recognition unit are recognized without a selective vertical movement of component holding members holding these components by drive of the single drive unit and without a change in heights at which the surfaces are located, and components of which the surfaces to be recognized are out of the recognizable range of the recognition unit are recognized after performing a positioning operation via vertical movement of component holding members holding these components, so as to bring the surfaces to be recognized of these components into the recognizable range of the recognition unit.
According to an eighth aspect of the present invention, there is provided a component recognizing apparatus as defined in any one of the fifth to seventh aspects, wherein shapes of the components are adapted to be recognized when the surfaces to be recognized of the components are recognized.
According to a ninth aspect of the present invention, there is provided a component mounting apparatus comprising:
According to a tenth aspect of the present invention, there is provided a component mounting apparatus as defined in the ninth aspect, wherein the plurality of components held by the plurality of component holding members and having the surfaces to be recognized at different heights, have such a variation in height that not all the surfaces to be recognized of the plurality of components are within the recognizable range of the recognition unit when bottom end surfaces of the plurality of component holding members are situated at an identical height.
According to an eleventh aspect of the present invention, there is provided a component mounting apparatus as defined in the ninth aspect, wherein, from among the plurality of components held by the plurality of component holding members and having the surfaces to be recognized of different heights, which components have such a variation in height that not all the surfaces to be recognized of the plurality of components are within the recognizable range of the recognition unit when the bottom end surfaces of the plurality of component holding members are situated at an identical height, components of which the surfaces to be recognized are within the recognizable range of the recognition unit are recognized without a vertical movement of component holding members holding these components and without a change in heights at which the surfaces are located, and components of which the surfaces to be recognized are out of the recognizable range of the recognition unit are recognized via the recognition unit after performing a positioning operation via a selective vertical movement of component holding members holding these components by drive of the single drive unit, so as to bring the surfaces to be recognized of these components into the recognizable range of the recognition unit.
According to a twelfth aspect of the present invention, there is provided a component mounting apparatus as defined in any one of the ninth to eleventh aspects, wherein shapes of the components are adapted to be recognized when the surfaces to be recognized of the components are recognized.
According to a thirteenth aspect of the present invention, there is provided a component mounting apparatus as defined in any one of the ninth to twelfth aspects, further comprising: a table which is adapted to be vertically moved by the single drive unit; and cylinders which are fixed to the table, corresponding to the component holding members, and are each adapted to bring a tip of a piston into contact with only a selected component holding member so as to be vertically moved from among the plurality of component holding members, and thereby transmit vertical movement of the table to the selected component holding member.
According to a fourteenth aspect of the present invention, there is provided a component recognizing method as defined in any one of the first to fourth aspects, further comprising:
According to a fifteenth aspect of the present invention, there is provided a component recognizing method as defined in the fourteenth aspect, wherein a plurality of sets of parameters of target positions and positioning operation starting positions are provided, and continuous positioning operations are thereby executed with provision of a plurality of timings.
According to a sixteenth aspect of the present invention, there is provided a component recognizing method as defined in the fifteenth aspect, further comprising, with a plurality of positioning operation ending positions corresponding to the plurality of positioning operation starting positions provided, judging whether individual positioning operations during continuous positioning operations, which were started at the plurality of positioning operation starting positions, have reached respective positioning operation ending positions or not so as to detect whether respective positioning operations have been completed normally or not.
According to a seventeenth aspect of the present invention, there is provided a component recognizing apparatus as defined in any one of the fifth to eighth aspects, comprising:
According to an eighteenth aspect of the present invention, there is provided a component recognizing apparatus as defined in the seventeenth aspect, wherein a plurality of sets of parameters of target positions and positioning operation starting positions are provided, and thereby the second control unit is adapted to execute continuous positioning operations with provision of a plurality of timings.
According to a nineteenth aspect of the present invention, there is provided a component recognizing apparatus as defined in the eighteenth aspect, wherein with a plurality of positioning operation ending positions corresponding to the plurality of positioning operation starting positions provided, the second control unit is adapted to judge whether individual positioning operations during continuous positioning operations, which were started at the plurality of positioning operation starting positions, have reached respective positioning operation ending positions or not, and thereby detects whether respective positioning operations have been completed normally or not.
According to a twentieth aspect of the present invention, there is provided a component mounting apparatus as defined in the ninth aspect, wherein the single drive unit is a single motor, and the single motor is adapted to rotationally drive a ball screw and thereby vertically move a table that is in screw engagement with the ball screw,
According to a twenty-first aspect of the present invention, there is provided a component mounting apparatus as defined in the twentieth aspect, further comprising a transverse movement motor for moving the component holding members in a transverse direction, wherein
According to a twenty-second aspect of the present invention, there is provided a component mounting method in which a plurality of components from component feeding units are held by the plurality of component holding members, the components are thereafter recognized via the component recognizing method as defined in any one of the first to fourth and fourteenth to sixteenth aspects, postures of the plurality of components held by the plurality of component holding members are thereafter corrected on a basis of a recognition result, and the components are thereafter installed onto an object to be installed.
According to a twenty-third aspect of the present invention, there is provided a component mounting apparatus which is adapted to hold a plurality of components from component feeding units by the plurality of component holding members, thereafter recognize the components with the recognition unit of the component recognizing apparatus as defined in any one of the fifth to eighth and seventeenth to nineteenth aspects, thereafter correct postures of the plurality of components held by the plurality of component holding members on a basis of a recognition result, and thereafter install the components onto an object to be installed.
According to a twenty-fourth aspect of the present invention, there is provided a component recognizing method as defined in the first aspect, wherein
According to a twenty-fifth aspect of the present invention, there is provided a component recognizing method as defined in the first aspect, wherein
According to a twenty-sixth aspect of the present invention, there is provided a component recognizing method as defined in the first aspect, wherein
According to a twenty-seventh aspect of the present invention, there is provided a component recognizing apparatus as defined in the fifth aspect, further comprising a control unit which is adapted to move the plurality of component holding members, holding the plurality of components having the surfaces to be recognized at different heights, in one direction over the one recognition unit, thereafter move the plurality of component holding members in a reverse direction opposite to the one direction over the one recognition unit with heights at which are located the plurality of component holding members being changed, perform imaging via the recognition unit of each of the plurality of components held by the plurality of component holding members during respective movement of the plurality of component holding members in the one direction and in the reverse direction, and recognize the surfaces to be recognized of only components having the surfaces to be recognized brought into the recognizable range of the recognition unit, from among the plurality of components.
According to a twenty-eighth aspect of the present invention, there is provided a component recognizing apparatus as defined in the fifth aspect, further comprising a control unit which is adapted to move the plurality of component holding members holding the plurality of components having the surfaces to be recognized at different heights in one direction over the one recognition unit, recognize the surfaces to be recognized of only components having the surfaces to be recognized brought into the recognizable range of the recognition unit, from among the plurality of components held by the plurality of component holding members, move the plurality of component holding members in a reverse direction opposite to the one direction over the one recognition unit after changing heights at which the plurality of component holding members are located, and recognize the surfaces to be recognized of only components having the surfaces to be recognized brought into the recognizable range of the recognition unit, from among the plurality of components held by the plurality of component holding members.
According to a twenty-ninth aspect of the present invention, there is provided a component recognizing apparatus as defined in the fifth aspect, further comprising: another recognition unit capable of recognizing surfaces to be recognized of components at heights different from those of components which are recognized by virtue of the one recognition unit; and
According to a thirtieth aspect of the present invention, there is provided a component recognizing method comprising:
According to a thirty-first aspect of the present invention, there is provided a component recognizing apparatus comprising:
These and other aspects and features of the present invention will become clear from the following description taken in conjunction with the preferred embodiments thereof with reference to the accompanying drawings, in which:
Before description of the present invention proceeds, it is to be noted that like parts are designated by like reference numerals throughout the accompanying drawings.
Embodiments of the present invention will now be described in detail with reference to the drawings.
Hereinbelow, a component recognizing method and apparatus and a component mounting method and apparatus according to a first embodiment of the present invention will be described with reference to the drawings.
In
A configuration of component mounting apparatus 500 in which the head unit 60 is installed is shown in
In such a component mounting apparatus 500 as shown in
Hereinbelow, operations of the head unit 60 of the component mounting apparatus of the first embodiment under control of the main controller 101 will be described with reference to
In the head unit 60, forward or reverse rotational drive of the rotating shaft of the motor 2 provided on fixed frame 1 moves the table 3 vertically, motive power of this vertical movement is transmitted to nozzles corresponding to selected cylinders, from among the first to tenth nozzles 24 to 33, and the corresponding nozzles move vertically in response to the movement of the table 3, because driving forces of the selected cylinders, from among the first to tenth cylinders 4 to 13, overcome reactive forces of springs corresponding to the selected cylinders, from among the first to tenth springs 14 to 23, in an upward direction, i.e., in direction B. To be more specific, in a case that eighth nozzles 31 is moved vertically with vertical movement of the table 3 as shown in
In
For recognition of the component 57 sucked and held by the second nozzle 25 in
For recognition of component 58 sucked and held by the third nozzle 26 in
For recognition of the component 59 sucked and held by the fourth nozzle 27 in
After that, bottom surfaces of components sucked and held by other nozzles not shown in
Upon accomplishment of this imaging, the image processing unit 96 performs recognition processing, on the basis of image data, of electronic components imaged by the recognition camera 61. After that, postures of the components sucked and held by the nozzles are corrected on the basis of a result of the recognition processing and then the components are installed (mounted) at predetermined positions on an object to be installed, such as a board.
For correction of postures of the components, the frame 1 is provided with a θ-direction driving motor 215 for correction in a rotational direction about nozzle shafts, i.e., in a direction θ, and forward or reverse rotation of a gear wheel 215a on a rotational shaft of the θ-direction driving motor 215 causes advance or retreat movement in a transverse direction of a rack 216 meshing with the gear wheel 215a and thereby causes forward or reverse rotations of gear wheels 217 fixed to the nozzles, so that all the nozzles can be rotated forwardly or reversely in unison in the direction θ.
A working example of the first embodiment is such an electronic component mounting apparatus as shown in
In accordance with the first embodiment, shapes, heights, and the like of the components 56 to 59 of which surfaces to be recognized are at different heights can be continuously recognized by moving the nozzles 24 to 33 of the head unit 60 vertically in general under control of the main controller 101 during component shape recognition in the component mounting apparatus, according to heights at which the surfaces to be recognized of the components to be recognized 56 to 59 are located. This arrangement eliminates repetition of a component recognizing operation in which, for example, only components having surfaces to be recognized at similar heights are held and recognized and, with this arrangement, components having surfaces to be recognized at different heights can be held at the same time and component recognizing operations can be performed continuously, regardless of the heights at which the surfaces to be recognized are located, so that an improvement in component mounting tact time (mounting process time) can be achieved. That is, even though the surfaces to be recognized of the components 56 to 59 held by a plurality of nozzles 24 to 33 cannot be accommodated all at once in the recognizable range L of the recognition camera 61, components having the surfaces to be recognized at different heights can be held at the same time and component recognizing operations can be performed continuously, by moving each of the nozzles 24 to 33 of the head unit 60 vertically so that each of the surfaces to be recognized of the components 56 to 59 comes into the recognizable range L.
Adjustment of heights at which components are located is achieved by the motor 2, i.e., a single drive unit, though such adjustment conventionally has required drive units of which a number of drive units corresponds to a number of nozzles, and thus cost and weight of the apparatus can be reduced.
A surface of a component to be recognized by the recognition camera 61 is not confined to a bottom surface of the component. Examples of such a surface are as follows. In a component having protruding electrodes shaped like balls on its bottom surface, such as BGA (Ball Grid Array) and CSP (Chip Size Package) shown in
Hereinbelow, a second embodiment of the present invention will be described with reference to the drawings.
For recognition of a height at which a surface to be recognized of a component is located in the first embodiment, the height at which the surface to be recognized of the component is located is required to be altered by a vertical movement in the event that the height at which the surface to be recognized of a sucked component is located differs from that of a formerly recognized component, and a positioning control apparatus and method according to the second embodiment of the present invention are capable of detecting accurately a starting time of driving vertical movement, i.e., positioning time. That is, the positioning control apparatus and method are such that an actuator, such as a servo motor corresponding to motor 2 of the drive unit, is driven to control a position of a load by a ball screw or the like serving as a rotating shaft of the motor 2, and a velocity curve is produced for positioning control with parameters, for example, of a target position, i.e., a height position where a surface to be recognized of a component is to be positioned by vertical movement of the surface, a maximum velocity during movement up to the target position, and a maximum acceleration during movement up to the target position. The positioning control apparatus and method are suitable for the component recognizing apparatus and method, and the component mounting apparatus and method, according to the first embodiment.
In other words, the positioning control apparatus and method according to the second embodiment are inexpensive and are capable of reducing a delay in a detection of a starting time of a positioning operation, and starting vertical movement at an arbitrary time, by providing parameters of a positioning operation starting position and specification of a shaft to be positioned and starting a positioning operation automatically upon arrival at the positioning operation starting position of the shaft specified by the shaft specification.
Herein, the term “operation starting position” refers to a position at which timing is provided for starting a vertical positioning operation to bring to within a recognizable range a surface to be recognized that is moving in a transverse direction, i.e., in N-direction in
For operation in vertical direction, the positioning control apparatus according to the second embodiment of the present invention produces, during the vertical movement, a velocity curve during vertical movement of a selected component holding member with parameters of a target position in a direction of height at a time when vertical movement of the selected component holding member is controlled by virtue of the drive unit so as to position a surface to be recognized of the component within a recognizable range of the recognition unit, a maximum velocity during the vertical movement of the selected component holding member up to a target position, and a maximum acceleration during the vertical movement of the selected component holding member up to the target position, and automatically starts a positioning operation of the selected component holding member driven by the drive unit on the basis of the velocity curve in response to a positioning operation starting instruction upon arrival at the positioning operation starting position of the selected component holding member moving transversely toward the recognition unit, so that the vertical operation can be started at an arbitrary time without delay in detection. Herein, the term “target position” refers to a terminal position of vertical movement, for example, a position in the direction of height in which the component 57 on the second nozzle 25 can be recognized, during ascent from a position for the first nozzle 24 to a position for the second nozzle 25. A positioning control apparatus according to a first aspect of the present invention is provided with parameters of a positioning operation starting position and a shaft specification, and automatically starts a positioning operation in response to a positioning operation starting instruction and upon arrival at the positioning operation starting position of a shaft specified by the shaft specification.
This arrangement ensures a positioning in which an arbitrary positioning operation starting time is provided accurately and in an inexpensive manner.
A positioning control apparatus according to a second aspect of the present invention is provided with parameters of a plurality of target positions and a plurality of positioning operation starting positions of the first aspect, and automatically starts a positioning operation in response to a positioning operation starting instruction and upon arrival at the positioning operation starting positions of a shaft specified by provided shaft specifications, and executes a plurality of positioning operations.
This arrangement ensures positioning in which an arbitrary positioning operation starting time is provided a plurality of times accurately and in an inexpensive manner, and ensures continuous positioning.
A positioning control apparatus according to a third aspect of the present invention has the second aspect provided with parameters of a plurality of positioning operation ending positions and detects normal accomplishment of individual positioning operations during a continuous operation.
This arrangement ensures detection of normal accomplishment of individual positioning operations during a continuous positioning operation and ensures an instantaneous suspension upon occurrence of an abnormal condition.
In a positioning control apparatus according to a fourth aspect of the present invention, an electronic component mounting apparatus is provided with the positioning control apparatus of the first aspect.
In a positioning control apparatus according to a fifth aspect of the present invention, an electronic component mounting apparatus is provided with the positioning control apparatus of the second aspect.
In a positioning control apparatus according to a sixth aspect of the present invention, an electronic component mounting apparatus is provided with the positioning control apparatus of the third aspect.
This configuration will be specifically described in correspondence to the first embodiment as follows. For the main controller 101, a target position (Pt) of a load in a vertical movement device for the nozzles (a device composed of the motor 2, the table 3, the first to tenth cylinders 4 to 13, and others) is a target position at a time when vertical movement of a selected component holding member such as a nozzle is controlled by virtue of the drive unit so as to position a surface to be recognized of the component within a recognizable range of the recognition unit, and a target position (Pt) of a load in a transverse movement device for the nozzles, i.e., a transverse movement device for the head unit (a device composed of the transverse movement motor and others) is a vertical drive starting position for recognition of a surface to be recognized of the component within a recognizable range of the recognition unit, that is, a vertical drive starting position for the selected nozzle. A maximum velocity (Vmax) during movement up to the target position is a maximum velocity during vertical movement or transverse movement of the selected nozzle up to the target position. A maximum acceleration (αmax) during movement to the target position is a maximum acceleration during vertical movement or the transverse movement of the selected nozzle to the target position. The positioning operation starting position (Pa) is a starting position of a positioning operation in the direction of height and in a transverse direction of the selected nozzle driven by the motor 2 and the transverse movement motor. The shaft specification (A) is the selection of the selected nozzle. The positioning operation starting instruction (C) is a starting instruction of a positioning operation in the direction of height and in the transverse direction of the selected nozzle driven by the motor 2 and the transverse movement motor.
The above-mentioned term “load” refers to an actuator and its mechanical device that move the frame 1, which is a base of the table 3, as a load in the transverse direction, i.e., in horizontal direction (in the N-direction). That is, the load in the device for the transverse movement, i.e., the movement in the right-and-left direction is the frame 1, and the load in the device for the vertical movement is the table 3. The positioning controller 102 calculates velocity curves during both the vertical movement and the transverse movement of the selected nozzle on the basis of instructions provided by the main controller 101, and outputs velocity instructions based on these calculated velocity curves. The servo drivers 103 and 106 drive and control the servo motors on the basis of velocity instructions provided by the positioning controller 102, and correspond to the transverse movement servo driver 103 and the vertical drive servo driver 106 for a plurality of suction nozzles 24 to 33 as an example of a plurality of component holding members. The servo motors 104 and 107 attached to the mechanical devices correspond to the transverse movement servo motor and the vertical drive motor 2 for a plurality of suction nozzles. The mechanical devices 105 and 108 to be finally positioned correspond to the transverse movement device for transverse movement and the vertical movement device for the nozzles.
Operations of calculation of the velocity curves and of output of an instructive velocity that are executed by the positioning controller 102 will be described below with reference to
The main controller 101 initially outputs for the transverse movement driver 103 instructions of a target position for transverse movement, a maximum velocity (V103max), and a maximum acceleration (α103max) without providing instructions of a positioning operation starting position and a shaft specification (selection of a nozzle) for the driver 103, outputs for the vertical driver 106 instructions of a positioning operation starting position and a shaft specification and instructions of a target position for vertical drive, a maximum velocity (V106max), and a maximum acceleration (α106max), and outputs a positioning operation starting instruction. The positioning controller 102 is then switched from a status (step #1 in
Next, the transverse movement driver 103 has no shaft specification and therefore goes from step #2 in
Next, the vertical driver 106 has a shaft specification that specifies a nozzle to be selected for selecting a nozzle to be vertically driven from among a plurality of nozzles, and therefore goes from step #2 in
When the selected nozzle then reaches the positioning operation starting position, velocity instruction setting the maximum velocity (V106max) and the maximum acceleration (α106max) is outputted for the vertical driver 106 (step #5 in
After that, the positioning controller 102 is brought into a status (step #1 in
With this configuration, a positioning operation of each selected nozzle can be started accurately and in an inexpensive manner with arbitrary timing.
In accordance with the second embodiment, the positioning operation for a selected component holding member driven by the drive unit on the basis of the velocity curve is started automatically with a positioning operation starting instruction, upon arrival at a positioning operation starting position of the selected component holding member that has been moving transversely toward the recognition unit, and therefore, the positioning operation can be started accurately and in an inexpensive manner with arbitrary timing.
The present invention is not limited to the above embodiments but may be implemented in other various forms.
For example, a plurality of parameters of target positions and positioning operation starting positions may be provided for executing processes shown in
On the other hand, a plurality of positioning operation ending positions may be added for executing processes shown in
With such a positioning control apparatus provided for or applied to an electronic component mounting apparatus, such as in the first embodiment, that requires positioning at high speed with high accuracy, positioning operations can be started accurately and in an inexpensive manner with arbitrary timing; however, it is needless to say that application is not limited to the above.
The second embodiment can be applied not only to a component mounting apparatus and method but to a positioning control apparatus and method for driving a plurality of actuators such as servo motors, and controlling positions of loads by a ball screw or the like, so that positioning operations can be started accurately and in an inexpensive manner with arbitrary timing. That is, an apparatus for driving a plurality of actuators such as servo motors and controlling positions of loads by a ball screw or the like can be configured so that the apparatus has the functions of producing a velocity curve with component recognizing apparatus parameters of a target position, a maximum velocity during movement up to a target position and a maximum acceleration during movement up to the target position, and starting a positioning operation in response to a positioning operation starting instruction. Parameters of a positioning operation starting position and a shaft specification are provided, a positioning operation is automatically started upon provision of a positioning operation starting instruction and upon arrival at the positioning operation starting position of a shaft specified by the provided shaft specification, and positioning is thereby executed with arbitrary timing.
That is to say, in a case that timing for starting positioning of one load must be provided according to position of another load, and the timing for starting the positioning must be changed during positioning control for driving actuators such as servo motors and controlling positions of loads by a ball screw or the like, a positioning operation of the other load is automatically started upon arrival of the position of one load at a positioning operation starting position, and a delay in detection is thereby reduced and the positioning operation can be started in an inexpensive manner with arbitrary timing. In a case that timing for starting the positioning of one load must be provided according to the position of the other load, for example, when operations of vertical movement and movement in a transverse direction, i.e., in a right-and-left direction, are made by virtue of the servo drivers 103 and 106, the motors 104 and 107, and the mechanical devices 105 and 108, the position in the right-and-left direction changes with sizes of components in a direction of height of the components, and in direction of movement to above the recognition device. A timing for starting the vertical movement accordingly changes and, therefore, a timing for starting positioning of the other load, e.g., in the vertical direction must be provided according to the position of one load, e.g., in the right-and-left direction in some cases.
As a result, a delay in detection can be reduced and a positioning control by which positioning operations are started in an inexpensive manner with arbitrary timing can be executed, by providing parameters of a positioning operation starting position and a shaft specification, and starting automatically a positioning operation upon arrival at the positioning operation starting position of a shaft specified by the shaft specification.
In such a configuration, a plurality of parameters of target positions and positioning operation starting positions may be provided so that continuous positioning operations can be executed accurately and in an inexpensive manner with arbitrary timing.
In such a configuration, furthermore, a plurality of positioning operation ending positions may be added so that normal completion of each positioning operation during continuous positioning operations can be detected.
In accordance with the second embodiment, the following issues can be resolved.
Conventionally, such a positioning control arrangement for a load, as shown in
As shown in
In recent years, particularly, mounting at high speed with high accuracy has been demanded, and there have been provided devices which recognize a plurality of components and install the components at a high speed by recognizing with a recognition unit 221 a shape and suction posture of a component 220 sucked and held by a nozzle while moving the nozzle or the like in the direction of an arrow, as shown in
For recognition of height at which a surface to be recognized of a component is located, however, the height at which the surface is located when the component is moving is altered by a vertical movement device each time the height at which the surface to be recognized of the sucked component is located differs from that of the formerly recognized component. This operation requires a device for detecting a positioning timing of the vertical movement device, and a variation in timing for each component makes the device complicated and expensive and impedes a speed-up by a delay in detection.
According to the second embodiment, by contrast, a device for detecting a positioning timing of the vertical movement device is not required. Besides, positioning can be executed with arbitrary timing by producing a velocity curve with component recognizing apparatus parameters of a target position, a maximum velocity during movement up to the target position, and a maximum acceleration during movement up to the target position, providing a function of starting a positioning operation in response to a positioning operation starting instruction, providing parameters of a positioning operation starting position and a shaft specification, and starting the positioning operation automatically upon provision of a positioning operation starting instruction and upon arrival at the positioning operation starting position of a shaft specified by the provided shaft specification, and therefore, positioning operations can be started accurately and in an inexpensive manner with arbitrary timing.
For recognition of a height at which a surface to be recognized of a component is located, particularly in a component mounting apparatus which has an increased number of nozzles for a purpose of achieving a speed-up as described with regard to the first embodiment and as shown in
Hereinbelow, a component recognizing method and apparatus, and a component mounting method and apparatus according to a third embodiment of the present invention will be described with reference to the drawings.
Prior to description of the third embodiment, an object of the embodiment will be described.
In recent years, high productivity in electronic component mounting apparatus for mounting electronic components onto circuit boards has been demanded with miniaturization and an increase in a variety of electronic components, and with an increase in an amount of electronic components to be mounted. In particular, a further speed-up in recognition of electronic components and in positional correction of electronic components has been demanded.
There have been known electronic component mounting apparatus having a component feeding unit for feeding electronic components, a head unit equipped with nozzles for sucking and holding electronic components, a drive device for moving the head unit to a specified position, a component mounting area having circuit boards on which electronic components are to be mounted, and a recognition area equipped with a line sensor for imaging a holding status of electronic components.
In such an electronic component mounting apparatus, a component recognition process is configured as shown in
When the electronic components 401 are imaged by the line sensor 405, a height (a distance) from the line sensor 405 to a bottom surface of an electronic component 401 is preferably set so as to coincide with the focus of the line sensor 405. Therefore, heights of the nozzles 402 are required to be set so as to be changed in accordance with shapes of the electronic components 401, particularly in accordance with thicknesses of the components 401. Herein, the height (distance) is defined as a component holding height, and a component holding height that causes a component to be imaged and come into the focus of the line sensor 405 is defined as a focus coincident height. A component holding height can be changed by vertical movement of the nozzles 402 with use of the vertical drive device 413.
Operations of a component recognizing method according to a prior art with such a configuration will be described.
Four electronic components 401 are sucked and held by the head unit 403 equipped with four nozzles 402, and the head unit 403 is moved to a start position in a recognition area equipped with the line sensor 405. On the basis of the control by virtue of the main control unit 407, the drive control unit 404 moves the head unit 403 at a constant velocity in the X-direction over the line sensor 405 and a holding status of each of the four electronic components 401 is imaged, with component holding heights of the nozzles 402 set at a focus coincident height fit for the four electronic components 401. When imaging of all the electronic components 401 is completed, the image processing unit 406 performs recognition processing on the basis of image data of the electronic components 401. After that, the main control unit 407 calculates correction quantities with respect to mounting positions in a circuit board on the basis of a recognition processing result obtained from the image processing unit 406 and each electronic component 401 is installed on the circuit board.
For imaging a holding status of a plurality of electronic components 401 at one time during a series of component recognition processes, however, use of the above-mentioned method has to be limited to electronic components 401 which have similar thicknesses when sucked and held by the head unit 403. When imaging is performed in a state in which electronic components having greatly different thicknesses exist in a plurality of electronic components 401 sucked and held by the head unit 403, the focus of the line sensor 405 is situated at a fixed height. On the other hand, component holding heights of the nozzles 403 exhibit a variation according to the electronic components sucked and held and having different thicknesses, and therefore, some of the electronic components to be imaged are out of the focus of the line sensor 405 and the holding status cannot be imaged accurately.
For this reason, each group of electronic components having similar thicknesses must be separately subjected to all processes during component suction holding, component recognition, and component installation, and there arises an issue in productivity of component mounting because of an extra time for movement of the head unit 403 and an occurrence of empty nozzles which are sucking no components.
In view of the above-mentioned issue, it is an object of the third embodiment to permit a series of component recognition operations to be made at one time and accurately with electronic components having different thicknesses sucked and held by the head unit and, consequently, to increase productivity of component mounting by reducing extra time for movement of the head unit and minimizing an occurrence of empty nozzles.
Hereinbelow, the third embodiment of the present invention will be described in detail with reference to
In
There is a difference in thickness, i.e., height in a vertical direction in
The component holding heights of the nozzles 302 are made variable according to sucked and held electronic components with different thicknesses, for a purpose of correcting to a focus coincident height the component holding heights of nozzles 302 having sucked and having held electronic components of which the bottom surfaces as an example of surfaces to be recognized do not coincide with the focus of the line sensor 305; that is, reside nearer or farther than the focal position of the line sensor 305, according to thicknesses of the electronic components, in contrast to the focus of the line sensor 305 situated at a fixed height. In such an apparatus in which component holding heights are variable, heights can be changed by vertical movement of the nozzles 302 by virtue of the vertical drive device 313. Details of the vertical movement of the nozzles 302 and the vertical drive device 313 which are provided for the head unit 303 will be described later.
A direction shown by reference character X1 in
A configuration and operation concerning the vertical movement of a plurality of nozzles 302 provided for the head unit 303 will be described below with reference to
As shown in
For vertical movement of a plurality of nozzles 302 in such a configuration, the vertical drive motor 316 fixed to the head unit board 315 is used as a drive source, rotational driving force of the vertical drive motor 316 is transmitted to the screw engagement section 317 provided in the L-type plate 318, and the L-type plate 318 is moved vertically, i.e., upward or downward by a predetermined amount with forward or reverse rotation in the screw engagement section 317. A plurality of nozzle selection valves 321 are fixed to the L-type plate 318, and the valves are configured so as to move cylinder units 320 selectively and vertically. Vertical movement by virtue of the nozzle selection valves 321 cannot be performed with an adjustment of an amount of the vertical movement, as distinct from vertical movement with the vertical drive motor 316 that is used as the drive source. That is because there are only two possible ways of the vertical movement, i.e., downward drive of a cylinder section 320 or a return to an original position of the cylinder section 320 with ON/OFF operation of a nozzle selection valve 321. A cylinder unit 320, driven downward selectively by a nozzle selection valve 321 in this way, pushes an upper end portion of a nozzle shaft 314 to move down a nozzle 302 connected to the nozzle shaft 314 and positions a tip of the nozzle 302 at a component holding height H1 shown in
When the nozzle selection valve 321 is in OFF state, the nozzle 302 is being pushed upward by a biasing force of a coil spring 319, because one end of the coil spring 319 is engaged with the nozzle shaft 314 serving as an axis of the coil spring 319. The tip of the nozzle 302 is therefore situated at a basic height H0 shown in
Operations of the component recognizing method according to the third embodiment in the above-mentioned configuration will be described with reference to
Three electronic components 301 and one electronic component 310 are sucked and held by the head unit 303 equipped with four nozzles 302 (see step 21 of
When these imaging operations are completed, the image processing unit 306 performs recognition processing on the basis of image data of the electronic components 301 and the electronic component 310 which have been imaged. At this time, the heights of the nozzles 302 have been set at the first focus coincident height fit for three electronic components 301, so that image data of recognition image imaged clearly is obtained from three electronic components 301; however, the height of the nozzle 302 holding the electronic component 310 of which the thickness is different from the thickness of the electronic components 301 has not been set at the second focus coincident height but has been set at the first focus coincident height, so that image data of recognition image imaged unclearly is obtained from the electronic component 310.
The drive control unit 304 subsequently switches the traveling direction to the direction X2 so as to reciprocate the head unit 303, and moves the head unit 303 at a constant velocity in the direction X2 over the line sensor 305 with heights of the nozzles 302 changed to and set at the second focus coincident height fit for the electronic component 310, and a holding status of the electronic components 301 and the electronic component 310 is imaged. To be more specific, for example, the main control unit 307 sets the heights of all the nozzles 302 at the second focus coincident height on the basis of group information acquired before, on condition that the components that can be recognized at the second focus coincident height are subsequently recognized (see step 25 of
When these imaging operations are completed, the image processing unit 306 performs recognition processing on the basis of image data of the electronic components 301 and the electronic component 310 which have been imaged. At this time, the heights of the nozzles 302 have been set at the second focus coincident height fit for the electronic component 310, so that image data of recognition image imaged clearly is obtained from the electronic component 310; however, the heights of the nozzles 302 holding three electronic components 301 of which the thickness is different from that of the electronic component 310 have not been set at the first focus coincident height but have been set at the second focus coincident height, so that image data of recognition image imaged unclearly is obtained from the three electronic components 301.
When recognition of the holding status of the electronic components 301 and the electronic component 310 is completed, the main control unit 307 calculates correction quantities with respect to installation positions in a circuit board on the basis of a recognition processing result obtained from the image processing unit 306. At this time, the main control unit 307 selects for the three electronic components 301 a recognition processing result in which the nozzles 302 were imaged at the first focus coincident height fit for the electronic components 301, and selects for the one electronic component 310 a recognition processing result in which the nozzle 302 was imaged at the second focus coincident height fit for the electronic component 310. To be more specific, for example, the main control unit 307 selects image data of the electronic components 301 fit for the first focus coincident height from image data of recognition image obtained from recognition at the first focus coincident height, and selects image data of the electronic component 310 fit for the second focus coincident height from image data of recognition image obtained from recognition at the second focus coincident height, on the basis of group information acquired before.
On the basis of the recognition processing result fit for each electronic component, correction quantities for positional offsets of the electronic components 301 and the electronic component 310 with respect to suction positions of the nozzles 302 are taken into account (see step 27 of
For imaging with the line sensor 305 in the third embodiment, image data of both components fit for a focus coincident height and components not fit for the focus coincident height is temporarily captured and stored in a memory 90 for image processing, and thereafter, only the image data of the components fit for the focus coincident height is finally selected under control of the main control unit 307; however, the embodiment is not limited to this arrangement. For example, image data of only components fit for a focus coincident height may be captured during imaging with the line sensor 305, with previous reference to thickness data of electronic components held by the nozzles 302, from among data stored in the memory 91 for mounting in which such information is stored as component data including types, thicknesses, widths, lengths, weights, and the like of components for use in component mounting, mounting order for suction of components and the like, types of nozzles installed in the head unit, and relations between types of nozzles and types of components (in other words, information showing which component is to be sucked by which nozzle).
According to the third embodiment, as described above, during the component recognizing method in the electronic component mounting apparatus having the head unit equipped with the plurality of nozzles each for sucking the electronic component, the X-Y drive device for moving the head unit to a specified position in X-Y directions, the vertical drive device for driving vertically the nozzles provided for the head unit, the drive control unit for controlling the X-Y drive device and the vertical drive device, the line sensor for imaging electronic components sucked by the nozzles, the image processing unit for performing recognition processing while controlling the line sensor, and the main control unit for controlling the drive control unit and the image processing unit, the head unit is reciprocated in the X-direction over the line sensor, and the nozzles are vertically moved simultaneously so as to change heights of electronic components sucked by the nozzles to specified heights and the electronic components are imaged with the line sensor, each time the traveling direction of the head unit is switched over.
In accordance with the third embodiment, electronic components having different thicknesses are respectively sucked and held by the plurality of nozzles provided for the head unit. When a holding status of those components is imaged in a series of component recognition processes, the nozzles are simultaneously moved vertically, for example, so as to have a height (a focus coincident height) fit for imaging of a group of electronic components of which thicknesses are within an identical range, from among all the sucked electronic components. The head unit is moved in a forward direction of the X-direction over the line sensor while scanning and imaging are executed. For a purpose of imaging accurately the remaining group of electronic components for which the height of the nozzles during the preceding imaging is unsuitable, the traveling direction of the head unit is subsequently switched to a reverse direction and the nozzles are simultaneously moved vertically so as to have a height (a focus coincident height) fit for imaging of the remaining group of electronic components. The head unit is then moved in the reverse direction over the line sensor while scanning and imaging are executed anew. As a result, after completion of imaging of all the electronic components, recognition results of the imaging at respective focus coincident heights fit for the electronic components with different thicknesses are selected, and thus a holding status of a plurality of electronic components with different thicknesses can be imaged accurately during a series of component recognition processes.
Hereinbelow, a fourth embodiment of the present invention will be described in detail with reference to
A configuration that is required for component recognition processes in an electronic component mounting apparatus of the fourth embodiment is basically the same as that in the third embodiment as described with reference to
As shown in
For component recognition processes, the head unit 303 is moved at a constant velocity in one direction, i.e., in X-direction during the component recognition processes in the fourth embodiment, while the head unit is reciprocated in both directions X1 and X2 in the third embodiment.
Hereinbelow, operations of a component recognizing method of the fourth embodiment will be described.
Three electronic components 301 and one electronic component 310 are sucked and held by the head unit 303 equipped with four nozzles 302, and the head unit 303 is moved to a start position in a recognition area equipped with the first line sensor 305 and the second line sensor 311.
On the basis of control by virtue of a main control unit 307, subsequently, a drive control unit 304 moves the head unit 303 at a constant velocity in the X-direction over the first line sensor 305 with heights of the nozzles 302 set at a first focus coincident height fit for the electronic components 301, and the first line sensor 305 images a holding status of the electronic components 301 and the electronic component 310.
When these imaging operations are completed, the image processing unit 306 performs recognition processing on the basis of image data of the electronic components 301 and the electronic component 310 which have been imaged.
The drive control unit 304 subsequently moves the head unit 303 at a constant velocity still in the X-direction over the second line sensor 311 with heights of the nozzles 302 changed to and set at the second focus coincident height fit for the electronic component 310, and the second line sensor 311 images a holding status of the electronic components 301 and the electronic component 310.
The image processing unit 306 performs recognition processing on the basis of image data of the electronic components 301 and the electronic component 310 which have been imaged.
When recognition of the holding status of the electronic components 301 and the electronic component 310 is completed, the main control unit 307 calculates correction quantities with respect to installation positions on a circuit board on the basis of a recognition processing result obtained from the image processing unit 306. At this time, the main control unit 307 selects for the three electronic components 301 the recognition processing result in which the head unit 303 was imaged by the first line sensor 305, and selects for the one electronic component 310 the recognition processing result in which the head unit 303 was imaged by the second line sensor 311. On the basis of these recognition processing results fit for each electronic component, correction quantities for positional offsets of the electronic components 301 and the electronic component 310 with respect to suction positions of the nozzles 302 are taken into account, and the electronic components are installed at installation positions on the circuit board.
In accordance with the fourth embodiment, for the component recognizing method in the electronic component mounting apparatus having the head unit equipped with the plurality of nozzles each for sucking the electronic component, the X-Y drive device for moving the head unit to a specified position in the X-Y directions, the vertical drive device for driving vertically the nozzles provided for the head unit, the drive control unit for controlling the X-Y drive device and the vertical drive device, the line sensors for imaging electronic components sucked by the nozzles, the image processing unit for performing recognition processing while controlling the line sensors, and the main control unit for controlling the drive control unit and the image processing unit, the plurality of line sensors are provided and arranged in the X-direction, and during movement of the head unit in one direction, i.e., in the X-direction over the plurality of line sensors, the nozzles are vertically moved simultaneously for each line sensor so that heights of the electronic components sucked by the nozzles are changed to specified heights over each line sensor, and the electronic components are imaged by each line sensor.
In accordance with the fourth embodiment, a plurality of line sensors are provided and arranged in the recognition area and, during movement of the head unit in one direction, i.e., in the X-direction over the plurality of line sensors, component holding heights of the nozzles can be changed to a focus coincident height fit for each group of electronic components having thicknesses different from those of other groups, over each line sensor by vertical movement of the nozzles, so that effects similar to those of the above-mentioned invention can be achieved.
The present invention can be configured with various aspects in addition to those shown in the above-mentioned embodiments.
For example, the third and the fourth embodiments have been described with reference to the examples configured with line sensors; however, the embodiments can be implemented in the same way, for example, even if three-dimensional sensors are substituted for the line sensors.
The third embodiment has been described with reference to an example in which two types of electronic components 301 and 310 having different thicknesses are made to pass and return two times over the line sensor 305 for the imaging of the components; however, the embodiment can be implemented in the same way, even if the number of times the head unit passes and returns, and the number of times the component holding heights of the nozzles 302 can be changed, are increased according to the number of types of electronic components with different thicknesses, for example, even if the head unit 303 is made to pass and return three or four times provided a plurality of electronic components having different thicknesses suck and held by the head unit are of three or four types. The fourth embodiment also can be implemented in the same way, even if the number of the line sensors and the number of times the component holding heights of the nozzles 302 can be changed are increased according to the number of types of electronic components with different thicknesses suck and held by the head unit.
The third and the fourth embodiments have been described with reference to the examples configured with four nozzles 302; however, the number of the nozzles is not limited to four but has only to be plural.
When only five nozzles out of ten nozzles 302 are used, for example, the main control unit 307 may be made to control so that only image data of components held by the five nozzles in use is captured on the basis of information on use of these five nozzles.
In the event that a positioning operation mode according to another embodiment of the present invention as shown in
As described above, according to the present invention, components of which surfaces to be recognized are located at different heights can be continuously recognized by moving component holding members vertically according to the heights at which the surfaces to be recognized of the components are located during recognition of the components by virtue of a recognition unit. This arrangement eliminates a necessity of a plurality of repetitions of a component recognizing operation according to a variation in heights at which the surfaces to be recognized are located, allows components to be held at the same time and allows component recognizing operations to be performed continuously regardless of the heights of the surfaces to be recognized, so that an improvement in component mounting tact time can be achieved.
Besides, adjustment of heights at which the surfaces to be recognized are located can be achieved by a single drive unit though, conventionally, this adjustment has required drive units of which the number corresponds to the number of nozzles, and thus cost and weight of the apparatus can be reduced.
In addition, a positioning operation can be started accurately and in an inexpensive manner with arbitrary timing, provided that a velocity curve for vertical movement of a selected component holding member is produced with parameters of a target position in a direction of height at a time when the vertical movement of the selected component holding member is controlled by virtue of a drive unit so as to position a surface to be recognized of a component within a recognizable range of a recognition unit, a maximum velocity during vertical movement of the selected component holding member up to the target position, and a maximum acceleration during vertical movement of the selected component holding member up to the target position, and the positioning operation of the selected component holding member driven by the drive unit on the basis of the velocity curve is automatically started in response to a positioning operation starting instruction upon arrival at a positioning operation starting position of the selected component holding member moving transversely toward the recognition unit.
In accordance with the fourteenth aspect of the present invention, recognition of a plurality of components of which surfaces to be recognized are located at two different heights can be achieved by moving component holding members vertically and controlling heights at which surfaces to be recognized of the components are located to within a recognizable range of a recognition unit, as occasion requires, by virtue of a single drive unit for moving the component holding members vertically.
In accordance with the fifteenth aspect of the present invention, a component recognizing method for recognizing components having not less than three different heights can be achieved by moving component holding members vertically and controlling heights at which are located surfaces to be recognized of the components to within a recognizable range of a recognition unit, as occasion requires, by virtue of a single drive unit for moving the component holding members vertically, on condition that a plurality of sets of parameters of target positions and positioning operation starting positions are provided so as to allow continuous positioning operations to be executed with provision of a plurality of timings.
In accordance with the sixteenth aspect of the present invention, there is provided a component recognizing method in which whether individual positioning operations during continuous positioning operations, which were started at a plurality of positioning operation starting positions, have reached positioning operation ending positions or not is judged, i.e., a component recognizing method in which a possibility of recognition is judged by detecting whether a height at which is located an objective surface of each component has been brought into a recognizable range or not.
In accordance with the seventeenth aspect of the present invention, there is provided a component recognizing apparatus in which a component recognizing method according to the fourteenth aspect is configured accurately and in an inexpensive manner.
In accordance with the eighteenth aspect of the present invention, there is provided a component recognizing apparatus in which the component recognizing method of the fifteenth aspect is configured accurately and in an inexpensive manner.
In accordance with the nineteenth aspect of the present invention, there is provided a component recognizing apparatus in which the component recognizing method of the sixteenth aspect is configured accurately and in an inexpensive manner.
In accordance with the twenty-fourth to thirty-first aspects of the present invention, a plurality of electronic components having different thicknesses sucked and held by a head unit can be imaged at one time and accurately during a series of component recognition processes. As a result, productivity of component mounting can be increased with a reduction in extra time for movement of the head unit and minimization of occurrence of empty nozzles.
Although the present invention has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications are apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims unless they depart therefrom.
| Number | Date | Country | Kind |
|---|---|---|---|
| 11/248380 | Sep 1999 | JP | national |
| 11/315064 | Nov 1999 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP00/05909 | 8/31/2000 | WO | 00 | 3/1/2002 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO01/19156 | 3/15/2001 | WO | A |
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