Component placing method

A component placing device to place a component on a board, including: a shaft having a lower portion and an upper portion; a component holder that is attached to the lower portion of the shaft in a state of being vertically displaceable and has a suction hole for holding the component by a negative pressure; an elastic body that biases the component holder downward with respect to the shaft; a servo motor that raises and lowers the shaft; and a controller that sets a thrust limit value for limiting a thrust of the servo motor and limits the thrust of the servo motor to be equal to or lower than the thrust limit value when the component holder is lowered toward the board. The thrust limit value is set within a range in which a load is smaller than a force by which the elastic body biases the component holder.

BACKGROUND

1. Technical Field

The present disclosure relates to a component placing device and a component placing method for placing a component at an installation position of a board.

2. Description of the Related Art

In a component placing device used for placing a component on a board in a manufacturing process of a component placing board, it is necessary to absorb fluctuation of an installation height position due to curvature deformation or the like of the board during a placing operation, and to control an installation load that presses the component at an installation position of the board to an appropriate value that corresponds to a target component. In order to realize the function, in the related art, a configuration has been known in which a load buffering spring is incorporated in a placing nozzle that holds a component and places the component on a board (refer to, for example, Japanese Patent Unexamined Publication No. 2008-227140). In the technology in the related art disclosed in Japanese Patent Unexamined Publication No. 2008-227140, an example in which, in the configuration in which a suction nozzle is biased by an elastic body, such as a coil spring, based on an approximate curve expression obtained by measuring a correlation between a pushing amount of the suction nozzle and a pressing load by a load sensor, load control during the placing operation is performed, is described.

SUMMARY

According to an aspect of the disclosure, there is provided a component placing device which places a component on a board, including: a shaft having a lower portion and an upper portion; a component holder that is attached to the lower portion of the shaft in a state of being vertically displaceable and has a suction hole for holding the component by a negative pressure; an elastic body that biases the component holder downward with respect to the shaft; a servo motor that raises and lowers the shaft; and a controller that causes the component holder to perform a raising and lowering operation for placing the component held by the component holder on the board by controlling the servo motor based on a preset operation pattern, in which the controller includes a thrust limiter that sets a thrust limit value for limiting a thrust of the servo motor and limits the thrust of the servo motor to be equal to or lower than the thrust limit value when the component holder is lowered toward the board, and in which the thrust limit value is set within a range in which a load that acts on the component from the component holder when the servo motor is driven with a thrust equal to the thrust limit value is smaller than a force by which the elastic body biases the component holder.

According to another aspect of the disclosure, there is provided a component placing method for manufacturing a component placing board in which a component is placed on a board by a component placing device including a shaft having a lower portion and an upper portion, a component holder that is attached to the lower portion of the shaft in a state of being vertically displaceable and has a suction hole for holding the component by a negative pressure, an elastic body that biases the component holder downward with respect to the shaft, a servo motor that raises and lowers the shaft, and a controller that causes the component holder to perform a raising and lowering operation for placing the component held by the component holder at an installation position of the board by controlling the servo motor based on a preset operation pattern, in which the controller moves the component holder that holds the component above the installation position of the board, sets a thrust limit value for limiting a thrust of the servo motor within a range in which a load that acts on the component from the component holder when the servo motor is driven by a thrust equal to the thrust limit value is smaller than a force by which the elastic body biases the component holder, lowers the component holder toward the installation position by controlling the servo motor based on the operation pattern, limits the thrust of the servo motor to be equal to or lower than the thrust limit value before the component lands at the installation position, and separates the component holder from the component that has landed at the installation position by raising the component holder after the component has landed at the installation position.

According to the disclosure, it is possible to stably control an installation load with high accuracy in a low-load region.

DETAILED DESCRIPTION

The above-described technology of the related art has the following problems. In other words, with miniaturization of electronic devices in recent years, components to be mounted are becoming smaller and thinner, and depending on the component type, an appropriate installation load at the time of component placement is substantially reduced compared to the related art. Since the component loading capacity is small in such a component type, it is necessary to control an installation load in a low-load region because there is a concern that component cracks and other damages are caused unless the installation load setting is not appropriate. However, in a configuration in which a suction nozzle is biased by an elastic body including the above-described related art, due to a variation in the sliding state of a mechanism that holds the suction nozzle, it is difficult to stably control the installation load with respect to micro component with high accuracy in the low-load region.

Here, an object of the disclosure is to provide a component placing device and a component placing method capable of stably controlling an installation load with high accuracy in a low-load region.

Next, embodiments of the disclosure will be described with reference to the drawings. First, with reference toFIG. 1, the configuration and function of component placing device1will be described. Component placing device1has a function of manufacturing a component placing board by placing a component on a board. InFIG. 1, board transporter2is disposed on an upper surface of base1ain an X direction (board transport direction). Board transporter2receives board3which is a target of component installation work from an upstream side device (not illustrated), transports and positions and holds board3at an installation working position in component placing device1. In other words, board transporter2functions as a board holder that holds board3. Component supplier5is disposed on both sides of board transporter2, and a plurality of tape feeders6are juxtaposed in component supplier5. Tape feeder6has a function of transporting a carrier tape that stores component P (refer toFIGS. 12A and 13) to a component pick-up position by placing head11described below.

On the upper surfaces of a pair of frame members7arranged in both end portions in the X direction in component placing device1, Y-axis moving table8driven by a linear motor is arranged in a Y direction. Similarly, X-axis moving table9driven by a linear motor is installed between Y-axis moving tables8so as to be movable in the Y direction. In X-axis moving table9, placing head11is installed so as to be freely movable in the X direction.

Y-axis moving table8and X-axis moving table9configure XY table10, and by driving XY table10, placing head11moves in the XY directions. Accordingly, placing head11picks up component P from tape feeder6by component holder31(refer toFIG. 2A) and installs component P on board3. Therefore, XY table10is a placing head moving mechanism for moving placing head11with respect to board holder that holds board3and component supplier5that supplies component P.

In a movement path of placing head11between board transporter2and component supplier5, component recognition camera12is disposed with an imaging direction directed upward. Component recognition camera12images component P which is in a state of being held by placing head11from below. By performing recognizing processing with respect to the imaging result, identification or position detection of component P held by placing head11are performed. Placing head11has placing head controller13built therein, and main body controller14is built in base1a.

The placing head controller13has a function of controlling a raising and lowering operation of component holder31(refer toFIG. 2A) that holds component P in placing head11. In addition, main body controller14has a function of controlling a device main body and issuing work instructions to placing head controller13. Placing head controller13and main body controller14configure controller15for controlling each portion of component placing device1. Controller15includes, for example, at least one processor and at least one memory that stores a program. By executing the program by a processor, control of each portion is executed.

In the embodiment, placing head11is attachable to and detachable from X-axis moving table9of XY table10which is a placing head moving mechanism.FIG. 2Aillustrates a section of X-axis moving table9in a state where placing head11is installed on X-axis moving table9. Back surface member23is provided on a back surface of placing head11having a configuration in which component holder31that holds the component is provided in a lower end portion. As illustrated inFIG. 2B, back surface member23is attachable to and detachable from (arrow a) moving base22provided on X-axis moving table9.

Moving base22is freely coupled to X-axis moving table9in the X direction via a pair of slide guides21. Moving base22is driven in the X direction with respect to the X-axis moving table9by linear motor20. Linear motor20has a configuration in which moving element20bcoupled to moving base22is opposed to stator20aarranged in the X direction on X-axis moving table9. In the lower end portion of moving base22, board recognition camera16is disposed with the imaging direction oriented downward. Board recognition camera16moves integrally with placing head11and images board3positioned below.

Connector holder25is coupled to upper end portion of moving base22via horizontal coupling member24. An upper portion of placing head11and connector holder25are connected to each other via piping connector26and wiring connector27. Piping connector26has a function of supplying pneumatic pressure or vacuum pressure from the device main body to placing head11. Wiring connector27has a function of supplying power and exchanging electric signals to and from placing head11from the device main body. Accordingly, placing head controller13built in placing head11and main body controller14built in base1aare connected to each other.

As illustrated inFIG. 2B, in a state where back surface member23is detached from moving base22, head side connectors26aand27aprovided in placing head11in piping connector26and wiring connector27are separated from main body side connectors26band27bprovided in connector holder25. In addition, when installing placing head11on another component placing device, back surface member23is fixedly coupled to moving base22of the other device, and head side connectors27aand26aare fitted to main body side connectors26band27bprovided in connector holder25of another device.

Next, with reference toFIGS. 3 and 4, the configuration of placing head11will be described. As illustrated inFIGS. 3 and 4, placing head11has a configuration in which a plurality (here, 12 nozzles in which six nozzle rows in which six nozzles are arranged in the X direction are disposed in two rows in the Y direction) of nozzle units30are disposed on a front surface of vertical back surface member23. Nozzle units30are held by shaft holder23aand servo motor attacher23bwhich are fixed to back surface member23, and an outer surface side thereof is enclosed by cover member11a.

As illustrated inFIG. 3, nozzle unit30has a configuration in which shaft35having upper portion36and lower portion32is raised and lowered by servo motor41, and accordingly, component holder31is raised and lowered. Shaft35is supported by shaft holder23a, and servo motor41is attached to servo motor attacher23b. Moving rod42that moves to be raised and lowered by servo motor41is coupled to upper portion36via rotating member40. Rotating member40is rotatably installed on moving rod42, and upper portion36is coupled to moving rod42in a form that allows relative rotation.

By driving servo motor41, component holder31installed on lower portion32of shaft35is raised and lowered, and accordingly, a raising and lowering operation for placing component P held by component holder31on board3is performed. Placing head controller13for causing the raising and lowering operation of component holder31is attached to back surface member23and connected to head side connectors27a, and with the configuration, as described above, it is possible to connect placing head controller13to main body controller14to be attachable and detachable.

As illustrated inFIG. 4, pulley37is attached to each upper portion36in a form that the rotation can be transmitted to the upper portion36while allowing the upper portion36to be raised and lowered. Belt37alooped to pulley37is driven by θ-axis motor38, and accordingly, each upper portion36can be rotated and a θ rotation operation for rotating component holder31around a nozzle axis becomes possible. The plurality of component holders31have a function of holding component P by a negative pressure introduced into suction holes31d(refer toFIG. 6A).

In other words, placing head11of component placing device1illustrated in the embodiment includes: a plurality of component holders31that hold component P by the negative pressure introduced into suction hole31d; a plurality of servo motors41that raises and lowers the plurality of component holders31; placing head controller13that causes component holder31to perform the raising and lowering operation for placing component P held by component holder31on board3by controlling the servo motor based on the preset operation pattern.

Next, with reference toFIG. 5, the configuration and function of nozzle unit30will be described. InFIG. 5, shaft35having upper portion36and lower portion32is held by shaft holder23a. Component holder31including nozzle31aand nozzle holder31bis attached to holder section32a(refer toFIGS. 6A and 6B) provided in lower portion32in a state of being displaceable in the up-down direction. Between lower portion32and nozzle holder31bof component holder31, biasing member33using a compression spring which is as an elastic body is installed. Biasing member33constantly presses component holder31downward with a predetermined biasing force previously set as a pressurization value.

Return spring39which is a compression spring is installed between pulley37attached to upper portion36and rotating member40. Return spring39allows an upward reaction force to act on rotating member40. In other words, when lowering component holder31, upper portion36is lowered against the reaction force of return spring39by the downward thrust of servo motor41. In addition, when raising component holder31, upper portion36is raised by the upward reaction force of return spring39by the upward thrust of servo motor41.

On shaft35, air joint34is provided to be positioned above lower portion32. Air joint34allows suction hole31dprovided in component holder31to communicate with an external negative pressure generating source (not illustrated). When raising and lowering component holder31, air joint34is guided to raising and lowering guide member34aprovided to extend downward from shaft holder23aand is raised and lowered together with shaft35.

Servo motor41that raises and lowers shaft35includes: linear motor41afor driving moving rod42inserted in the up-down direction to be raised and lowered; and encoder44for outputting a pulse signal in accordance with the movement of moving rod42. Encoder44includes: linear scale44aprovided in moving rod42; and movement detector44bwhich is provided in vertical member43so as to oppose linear scale44aand detects the movement of linear scale44a. Movement detector44boutputs an encoder pulse indicating the movement distance and direction of linear scale44ato position detector53(refer toFIG. 8) as a position signal.

Next, with reference toFIGS. 6A, 6B, and 7, a detailed configuration of component holder31and an installation operation for installing and holding component holder31to lower portion32will be described.FIGS. 6A and 6Billustrate a side surface in a state where component holder31is held by lower portion32, andFIGS. 6A and 6Billustrate side surfaces in two directions orthogonal to each other, respectively.

As illustrated inFIG. 6A, lower portion32is provided with holder section32afor holding component holder31. In fitter32bprovided in a hollow circular hole shape in holder section32a, slider31cprovided in a columnar shape in component holder31is fitted in a displaceable state in the up-down direction. Nozzle holder31bis provided in the lower portion of slider31c, and nozzle holder31bholds nozzle31aprovided with suctioner31ffor suctioning the component.

At the upper end of slider31c, pin31efor fixing the position of component holder31to holder section32ais provided in a shape that protrudes on both sides in a radial direction. In holder section32a, a guide groove for guiding pin31eto a fixed position is provided in a configuration described below. In other words, as illustrated inFIG. 6A, on the side surface of holder section32a, inserter32cwhich reaches a vertically upper part from the lower end surface of holder section32ais provided.

In the upper end portion of inserter32c, horizontal portion32dis provided within a range in which holder section32arevolves by a half turn. Furthermore, as illustrated inFIG. 6B, a terminal end portion of horizontal portion32dis connected to guide32ethat extends vertically downward to the middle of the height of holder section32a. In a state where component holder31is held by holder section32a, pin31eis positioned in the lower end portion of guide32e, and accordingly, component holder31is held by holder section32a. At this time, a predetermined clearance is ensured between the upper end portion of slider31cand a ceiling surface of fitter32b, and pin31ecan move in the up-down direction in guide32e. Accordingly, the position of component holder31in the up-down direction with respect to lower portion32is displaceable.

Suctioner31fcommunicates with suction hole31dformed on the inside of component holder31, and in a state where component holder31is held by holder section32a, suction hole31dis in a state of communicating with suction hole32fformed in lower portion32. Suction hole32fis connected to an external negative pressure generating source via air joint34(refer toFIG. 5), and accordingly, component P is held by the negative pressure by nozzle31ain component holder31.

In the above-described configuration, nozzle31a, nozzle holder31b, slider31c, suction hole31d, and pin31eare attached to lower portion32of shaft35in a state of being displaceable in the up-down direction, and configure component holder31having suction hole31dfor holding the component by the negative pressure. Biasing member33which is an elastic body is fitted to an outer circumference of slider31cbetween the lower end surface of holder section32aand nozzle holder31b. Biasing member33biases component holder31downward against lower portion32of shaft35.

Next, with reference toFIG. 7, an operation procedure for holding component holder31by holder section32aof lower portion32will be described. First, as illustrated inFIG. 7(a), in component holder31, pin31eprovided in slider31cis positioned with respect to inserter32cof holder section32a. In addition, in the state, component holder31is brought closer to holder section32a(arrow b) so as to make slider31cfitted to fitter32b.

Next, as illustrated inFIG. 7(b), while guiding pin31ewith inserter32c(arrow c), component holder31is raised, and when pin31ereaches horizontal portion32d, component holder31is rotated around the axis while guiding pin31eby horizontal portion32d. Accordingly, as illustrated inFIG. 7(c), pin31ereaches the terminal end portion of horizontal portion32d. After this, as illustrated inFIG. 7(d), while guiding pin31ewith guide32e(arrow e), component holder31is lowered. Accordingly, pin31eis positioned in the lower end portion of guide32e, and component holder31is in a state of being held by holder section32aof lower portion32.

Here, the relationship of forces that acts on nozzle unit30having the above-described configuration will be described with reference toFIG. 10. InFIG. 10, thrust T is a thrust generated by servo motor41and acts in a direction to push coupled shaft35downward via rotating member40. Weight W is the sum of the weights of the hatched parts indicating a movable portion in the drawing, that is, moving rod42, rotating member40, upper portion36, air joint34, lower portion32, component holder31and the like, and similar to thrust T, weight W acts in the direction of pushing shaft35downward.

Reaction force F1is a reaction force of return spring39and acts in a direction of pushing shaft35upward via rotating member40. Resistance F2is a resistance external force of a sliding guide or the like that slidably holds the above-described movable portion, and acts upward on shaft35driven in a lowering direction. In addition, load LF indicates a load when pressing a contact to which component holder31is lowered and abuts, for example, component P held by component holder31to the board.

InFIG. 10, in order to acquire thrust-load correlation data (refer toFIG. 11), a state where component holder31is pressed against load detector45(refer toFIGS. 8 and 9) having a function of measuring load LF, respectively, is illustrated. In addition, biasing force FP illustrated inFIG. 10is the pressurization value of biasing member33interposed between component holder31and lower portion32, and indicates the pressing force exerted on component holder31and lower portion32.

In a force application state described above, load LF is expressed by a relationship illustrated in an equation (1) in the drawing, that is, LF=T+W−F1−F2. Here, since weight W, reaction force F1, and resistance F2may be regarded as fixed values for same nozzle unit30, load LF uniquely depends on thrust T. In component placing device1illustrated in the embodiment, thrust T is set such that biasing force FP and load LF satisfy an inequality (2), that is, such that load LF is smaller than biasing force FP.

Setting thrust T such that load LF is smaller than biasing force FP has the following technical significance. In other words, in the related art, biasing member33plays a role of elastically supporting component holder31, and when the component held by component holder31is placed, the component is pressed to the board by the reaction force generated as biasing member33is pushed in.

On the other hand, in component placing device1illustrated in the embodiment, a limit value of load LF such that load LF for pushing down component holder31is smaller than biasing force FP of biasing member33is first defined as limit load LFL. In addition, thrust T of servo motor41that corresponds to limit load LFL is obtained as thrust limit value TL and stored in placing head controller13. In addition, when driving servo motor41in the actual component placing operation, servo motor41is controlled such that thrust T does not exceed thrust limit value TL.

By controlling thrust T of servo motor41in nozzle unit30in this manner, it is possible to place the component on the board by the pressing force of load LF itself without compressing biasing member33in a lowering operation of component holder31. Accordingly, even in a case where there are variations in the height of the board depending on the component installation position, it is possible to press the component to the board with load LF that can be controlled with high accuracy.

In addition, in order to control thrust T, in the embodiment, in placing head controller13that controls the operation of nozzle unit30of placing head11, thrust limit value TL that limits the value of thrust T of servo motor41is set for each servo motor41, and servo motor41is controlled based on set thrust limit value TL. The setting of thrust limit value TL is performed by referring to limit load LFL included in a command from main body controller14of the main body of component placing device1as the thrust-load correlation data (refer toFIG. 11) created in advance. Hereinafter, with reference toFIG. 8, a configuration in which controller15including placing head controller13and main body controller14is provided in order to execute the control processing in component placing device1will be described.

InFIG. 8, controller15for controlling entire component placing device1is configured with placing head controller13connected to main body controller14and main body controller14via wiring connector27. Main body controller14has a function of controlling operations, such as transporting board3in component placing device1and picking up the components from component supplier5by placing head11, and sending a control command to placing head controller13.

In other words, main body controller14controls at least XY table10(placing head moving mechanism) for moving placing head11and sends a command for performing the raising and lowering operation of component holder31to placing head controller13. In other words, controller15controls servo motor41that raises and lowers shaft35of nozzle unit30based on the operation pattern set in advance and stored as “standard operation pattern”58din second storage58, and accordingly, causes component holder31to perform the raising and lowering operation for placing the component held in component holder31on board3.

Servo motor controllers50(#1 to #12) that control servo motors41(#1 to #12) of nozzle unit30are provided for each of the plurality (here, 12) of nozzle units30disposed in placing head11are provided in placing head controller13. Each servo motor controller50includes motor driver51, thrust detector52, position detector53, landing detector54, timer55, thrust limiter56, first storage57, and second storage58.

Here, as described above, placing head11is configured to be attachable to and detachable from XY table10which is a placing head moving mechanism, and first storage57is a nonvolatile storage. With the configuration, even in a state where placing head11is detached from X-axis moving table9of XY table10and becomes a single unit, the stored contents can be held. Accordingly, even in a case where placing head11detached from one component placing device1is moved to another component placing device1, each nozzle unit30of placing head11can be correctly operated with reference to the correlation data stored in first storage57.

Motor driver51is a drive control device of servo motor41, supplies (arrow f) electric power to servo motor41based on the preset operation pattern, and drives servo motor41. In addition, a deviation from a target position or a target speed determined by the operation pattern is detected by a pulse signal sent from encoder44of servo motor41(arrow g), and servo motor41is driven by servo control for feeding back the detected deviation.

Thrust detector52has a function of detecting the thrust of servo motor41. In other words, thrust generated in servo motor41is detected by the current (arrow f) supplied from motor driver51to servo motor41or the current value (arrow h) notified from motor driver51. In the embodiment, the thrust of servo motor41is limited by the function of thrust limiter56based on thrust limit value TL described above.

Thrust limiter56obtains thrust limit value TL with reference to limit load LFL included in the control command from main body controller14as the thrust-load correlation data stored in first storage57which is the correlation data storage, and store thrust limit value TL as “thrust limit value”57ain first storage57. In addition, processing for setting obtained thrust limit value TL in motor driver51is executed (arrow i).

In other words, when component holder31is lowered and reaches thrust limit height TLh (refer toFIG. 13) set in advance as “thrust limit height”58cin second storage58, thrust limit value TL stored as “thrust limit value”57ain first storage57is set in motor driver51. In addition, when component holder31moves up to a position higher than thrust limit height TLh, the setting of thrust limit value TL in motor driver51is released.

In the configuration, thrust limiter56and motor driver51set thrust limit value TL for limiting the thrust of servo motor41based on the thrust-load correlation data and information on limit load LFL included in the control command from main body controller14, and when lowering component holder31toward board3, thrust limiter for limiting the thrust of servo motor41to be equal to or lower than thrust limit value TL is configured. Here, thrust limit value TL is set within a range in which the load that acts on the component from component holder31when driving servo motor41with the same thrust as thrust limit value TL is smaller than biasing force FP by which biasing member33which is an elastic body biases component holder31.

In addition, thrust limiter of the above-described configuration sets thrust limit value TL for limiting the thrust of servo motor41within a range that load LF that acts on the component from component holder31when servo motor41is driven is smaller than biasing force FP by which biasing member33biases component holder31, and limits the thrust of servo motor41to be equal to or lower than thrust limit value TL. Specifically, in the driving of servo motor41by motor driver51, the current to be supplied to servo motor41is limited such that the thrust becomes equal to or lower than thrust limit value TL.

Position detector53counts encoder pulses from encoder44of servo motor41. The count value is positional information indicating the position in the height direction of component holder31. In other words, position detector53has a height position measurement function of detecting the position in the height direction of component holder31based on the position signal from servo motor41. The installation position height measurement described later is performed by using the height position measurement function of position detector53.

Landing detector54detects that the component held by component holder31has landed on board3. The landing detection is performed by any of the following two methods. First, as one method, when thrust detector52detects that thrust T of servo motor41has reached set thrust limit value TL while thrust limit value TL is set and thrust T is limited by thrust limiter described above, it is detected that the component has landed on board3. In addition, as an alternative method to the method, it may also be detected that the component has landed on board3due to the stagnation of the encoder pulse output from encoder44of servo motor41.

Timer55has a function of measuring the elapsed time after the landing detector54detects the landing. Then, when the measured elapsed time is set in advance as an appropriate settling time and reaches “target time”58estored in second storage58, component holder31starts to rise. In the embodiment, placing head controller13of controller15controls servo motor41and raises component holder31when the elapsed time reaches “target time”58ebefore a raising start timing determined by the operation pattern stored in “standard operation pattern”58dof second storage58.

First storage57is a correlation data storage, and stores correlation data (thrust-load correlation data) indicating the relationship between thrust T of servo motor41and load LF generated at a tip end of component holder31for each of the plurality of servo motors. In addition, first storage57is a nonvolatile storage and can hold the stored contents even in a state where placing head11is detached from XY table10.

With reference toFIG. 11, the contents of the above-described thrust-load correlation data will be described.FIG. 11is a graph in which the horizontal axis indicates thrust T of servo motor41and the vertical axis indicates load LF generated at the tip end of component holder31. In nozzle unit30having the configuration illustrated inFIG. 10, thrust T and load LF are in a linear relationship in a practical target section, and in the graph ofFIG. 11, thrust T and load LF are in a relationship expressed by characteristic straight lines [L].

The characteristic straight line [L] is obtained as follows. First, load A and load B generated at the tip end of component holder31when servo motor41is driven with two thrusts A and B having different sizes are measured by load detector45illustrated inFIG. 9. In addition, inFIG. 11, a straight line that connects two data points (PA) and (PB) defined by (thrust A, load A) and (thrust B, load B) is taken as characteristic straight line [L].

In addition, when limit load LFL is specified by the control command transmitted from main body controller14at the time of executing the component placing operation, thrust that corresponds to limit load LFL on the characteristic straight line [L] is obtained as thrust limit value TL. In other words, limit load LFL applied to component P by component holder31when placing component P on board3and thrust limit value TL for limiting thrust T generated by servo motor41using the thrust-load correlation data illustrated inFIG. 11are calculated. The obtained thrust limit value TL is stored as “thrust limit value”57ain first storage57which is the correlation data storage for each of the plurality of servo motors.

In the driving of servo motor41in the component placing operation, thrust limit value TL stored in this manner is set in motor driver51at a predetermined timing, and the thrust is controlled such that the thrust of servo motor41is equal to or lower than thrust limit value TL. With the configuration, in component placing device1including the plurality of component holders31and servo motor41, it is possible to reduce variations in the load caused by variations in characteristics of servo motor41.

In the above-described thrust-load correlation data, thrust A is a first thrust and load A is a first load generated when servo motor41is driven with the first thrust. In addition, thrust B is a second thrust having a size different from the first thrust and load B is a second load generated when servo motor41is driven with the second thrust. In first storage57, the thrust-load correlation data is stored in a form of a digital value indicating “thrust limit value”57a, “thrust A”57b, “load A”57c, “thrust B”57d, and “load B”57e.

In addition, load A which is the first load and load B which is the second load are set so as to be smaller than biasing force FP for biasing component holder31by biasing member33which is the elastic body. Accordingly, in the load measurement using load detector45, it is possible to measure load LF without compressing biasing member33, and to correctly obtain the correlation between the thrust and the load.

Second storage58stores work execution data transmitted from main body controller14to placing head controller13, such as a height parameter for raising and lowering operation control in the installation operation or an operation pattern. These working execution data are created by installation work executer60of main body controller14based on the installation data for each board type illustrated in the followingFIG. 12B, and are transmitted to placing head controller13.

FIG. 12Aillustrates component placing board3* manufactured by placing the component on board3by a component mounting system including component placing device1illustrated in the embodiment. On the component mounting surface on which recognition mark3ais formed on board3, component placing range3bwhich is a target of component placement by component placing device1is set. In component placing range3b, component P is placed by component placing device1. In a range on the outside of component placing range3b, component P* is placed by another component placing device.

FIG. 12Billustrates installation data70which is referred to when placing component P in component placing range3bby component placing device1. Installation data70is stored in installation data storage64of main body controller14. Installation data70includes: “installation position No”70athat indicates the number of installation position of component P on board3by MP1, MP2, . . . ; “installation position coordinates (X, Y, θ)”70bthat indicates installation position coordinates of component P in each “installation position No”70a; “installation position height (Z)”70cthat indicates the installation position height of component P in each “installation position No”70a; and “component name”70dthat indicates the name of installed component P.

Next, the height parameter for raising and lowering operation control included in these work execution data will be described with reference toFIG. 13.FIG. 13schematically illustrates the positional relationship of the height parameters for control when servo motor41lowers shaft35(refer toFIG. 5) on which component holder31that holds component P is installed. InFIG. 13, the horizontal line drawn above indicates standby height Z0which is the position before starting the operation of component holder31.

In first example EX1illustrated on the lower left side, the installed state of component P in the ideal state is illustrated. In other words, here, a state where board3which is in an ideal state without deformation is set in the board holder at which the height is held correctly, and component holder31that holds component P is lowered with respect to board3, is illustrated. The upper surface of board3in the state indicates the mounting height Z1in the ideal state. Thrust limit height TLh which is the height at which thrust limit value TL is applied and thrust limit for limiting the thrust of servo motor41is started is set in the middle between standby height Z0to installation height Z1, and is stored in second storage58of placing head controller13in advance.

In addition, the height above installation thickness dimension d (here, a thickness dimension obtained by adding the thickness of component P, the thickness of land3c, and the thickness of joining solder S) from installation height Z1, is landing height ZC that indicates the height of component holder31when component P held by component holder31is in contact with the joining solder. In addition, the position above landing height ZC by predetermined deceleration height offset OFD is deceleration height Dh that defines a deceleration position for decelerating the lowering speed of component holder31from high speed to low speed. Further, the position below target height offset OFT in consideration of the prevention of swing from landing height ZC is target height Th which is a target for lowering component holder31.

Here, regarding deceleration height Dh, it is desirable to reduce deceleration height offset OFD as small as possible from the viewpoint of shortening the lowering time of component holder31to improve the productivity, and to set deceleration height Dh to be a height close to landing height ZC. However, in a case where mounting height Z1of board3of work target varies, the following inconvenience occurs depending at the installation position of deceleration height Dh.

In other words, when the deceleration height Dh is extremely low, there is a concern about placement trouble due to the landing of component P held by component holder31without reducing the lowering speed. Conversely, when deceleration height Dh is extremely high, there is a delay in operation time due to deceleration of the lowering speed from a timing that is earlier than necessary. In order to prevent such inconvenience, in component placing device1described in the embodiment, based on the actual installation height detected by the function of position detector53in the execution process of the component placing work, an appropriate deceleration height is dynamically set.

In second example EX2and third example EX3which are illustrated on the right side of first example EX1, indicates an installation state of component P in a state where the height position of board3is displaced upward only by variation Δ1and downward by variation Δ2from board3which is in the ideal state. The upper surface of board3in second example EX2illustrates installation height Z11in this state. In addition, the height above from installation height Z11only by installation thickness dimension d described above is landing height ZC1, and the position above from landing height ZC1only by the predetermined deceleration height offset OFD is deceleration height Dh1.

The upper surface of board3in third example EX3illustrates installation height Z12in this state. In addition, the height above from installation height Z12only by installation thickness dimension d is landing height ZC2, and the position below from landing height ZC1only by target height offset OFT1is target height Th1which is a target at which component holder31is lowered. Here, even in a case where the height of the assumed installation position is the lowest, the height is set such that the swinging does not occur. In addition, in second example EX2, illustration of the target height is omitted, and in third example EX3, illustration of the deceleration height is omitted.

The height parameters are stored in second storage58. Here, target height Th and deceleration height Dh are set for each operation of nozzle unit30in placing head11. In addition, “target height”58awhich is a target lowering height when component holder31is lowered in the component placing operation, and “deceleration height”58bwhich is a height that defines the timing for decelerating the speed of lowering component holder31from high speed to low speed, are stored after being updated each time. In addition, thrust limit height TLh is stored as “thrust limit height”58c.

“Standard operation pattern”58dis an operation pattern of the installation operation in placing the component by placing head11with respect to board3which is a target. The operation pattern includes a deceleration height for decelerating the speed of lowering component holder31from high speed to low speed and a target height which is a target lowering height of component holder31.

“Target time”58eis a settling time for maintaining a settled state where component holder31that holds component P is lowered and presses component P against board3. In the embodiment, when the elapsed time obtained by measuring elapsed time after landing detector54detects the landing by landing detector54reaches target time Ts stored as “target time”58e, component holder31is separated from moved from component P and is raised.

Main body controller14is connected with XY table10, board transporter2, component supplier5, touch panel68, board recognition camera16, component recognition camera12, notifier69, and load detector45. Main body controller14includes installation work executer60, swing detector61, installation position height measurer62, deceleration height computer63, installation data storage64, component information storage65, installation height storage66, and thrust-load correlation data acquirer67, as internal processing functional sections.

Based on the installation data (refer toFIG. 12B) stored in installation data storage64, installation work executer60controls XY table10, board transporter2, component supplier5, placing head11, component recognition camera12, and board recognition camera16. Accordingly, a series of work (refer to the flow illustrated inFIG. 19) for placing component P on board3is executed. Touch panel68is an operation input for displaying an input operation and an operation screen at the time of an input operation, and performs the input operation required when the above-described series of operations is executed. Notifier69is notifying means, such as a signal tower operating in a predetermined situation, a display screen, and the like, and in a case where an abnormal state is detected in the component placing operation by placing head11, the fact is notified.

Load detector45is a detection unit having a function of detecting load LF illustrated inFIG. 10. As illustrated inFIG. 9, load detector45includes load detecting device45a, such as a load cell, on the upper surface thereof, and the lower end portion of component holder31is brought into contact with load detecting device45aand pressed to measure load LF. Load detector45can be detachably connected to main body controller14via connector device45b. When the load measurement is required, as illustrated inFIG. 9, load detector45is disposed on base1aof placing head11.

After the thrust limiter of the above-described configuration limits the thrust of servo motor41, swing detector61detects that the thrust detected by thrust detector52has not reached set thrust limit value TL during a period to the raising start timing determined by the operation pattern set in advance, that is, that the component held by component holder31has not reached the upper surface of the board and the placing operation became “swing”.

In addition, in a case of detecting the swing by swing detector61, notifier69is operated to notify the fact. In the embodiment, it is possible to immediately detect “swinging” with a high possibility of mounting failure, and by notifying the fact, it is possible to rapidly perform response, such as prediction of the occurrence of a defect or correction of the target height of the component, and to stabilize the quality.

Installation position height measurer62measures the installation height indicating the height at an installation completion position which is the installation position at which component P is installed, based on the position in the height direction of component holder31detected by position detector53and the dimension of component P installed by component holder31, at a predetermined timing from the time when the component reaches the installation position of board3until immediately before component holder31starts raising. The plurality of measured installation heights of the plurality of installation completion positions are stored in installation height storage66. Deceleration height computer63uses at least one installation height stored in installation height storage66to calculate the deceleration height (refer to deceleration height Dh2illustrated inFIG. 17B) when the component is installed at an uninstallation position which is an installation position where the component has not yet been installed. In other words, in the embodiment, based on the installation height detected by position detector53with respect to the installation completion position on which the installation has already been executed on the same board3, the correction is performed by calculating the deceleration height for the uninstallation position which is the work target thereafter.

Here, with reference toFIGS. 18A and 18B, an example of the deceleration height correction by deceleration height computer63will be described.FIGS. 18A and 18Billustrate correction target positions of deceleration height correction. InFIGS. 18A and 18B, on the upper surface of board3, a plurality of installation positions MP1to MP7to which the components are installed are set. Among the installation positions, the installation position enclosed by a rectangular frame indicates the installation completion position which is the installation position where component P is installed.

InFIG. 18A, installation positions MP1, MP2, and MP3are the installation completion positions, and installation position MP4is the uninstallation position which becomes a target of the next installation operation. When setting the new deceleration height by the calculation instead of the preset deceleration height for installation position MP4which is the uninstallation position, it is determined whether or not the installation completion position exists within the range (here, within circular range C of radius R around installation position MP4) set in advance from the uninstallation position (installation position MP4).

In addition, in a case where the installation completion position exists, the deceleration height for the uninstallation position (here, installation position MP4) is computed based on the installation height measured for the installation completion position (here, installation position MP2). In other words, in this case, deceleration height computer63computes the deceleration height based on the installation height of the installation completion position that exists within the range preset from the uninstallation position. Deceleration height computer63calculates the installation height of installation position MP4from the installation height of installation position MP2. As an example, in a case where the installation height of installation position MP2is different from the installation height originally assumed, after assuming that the installation height of installation position MP4that exists in the vicinity thereof is also similarly different, installation height Z11(refer toFIG. 13) of installation position MP4is calculated. In addition, deceleration height computer63computes deceleration height Dh2at installation position MP4using the installation thickness dimension d of installation height Z11and installation position MP4and deceleration height offset OFD.

In addition, under the condition whether or not the installation completion positions exist more than the preset number in the vicinity of the uninstallation position that becomes that target of the installation operation, it may be determined whether or not the computation of the deceleration height is possible. InFIG. 18B, installation positions MP1, MP2, MP3, MP4, and MP5are the installation completion positions, and installation position MP6is the uninstallation position which becomes a target of the next installation operation. When setting the new deceleration height by the calculation instead of the preset deceleration height for installation position MP6which is the uninstallation position, it is determined whether or not the preset number (here, 3) of installation completion positions exist within the range (here, within circular range C of radius R around installation position MP6) set in advance from the uninstallation position (installation position MP6).

In addition, in a case where the preset number or more of installation completion positions exist, the deceleration height for the uninstallation position (here, installation position MP6) is computed based on the installation height measured for the installation completion position (here, installation positions MP3, MP4, and MP5). In other words, in this case, deceleration height computer63computes the deceleration height of the uninstallation position based on the installation height of the preset number of installation completion positions. In the calculation, for example, installation height Z11of installation position MP6is calculated from the average value of the plurality of installation heights. In addition, deceleration height computer63computes deceleration height Dh2at installation position MP6using the installation thickness dimension d of installation height Z11and installation position MP6and deceleration height offset OFD.

Installation data storage64stores the installation data (refer toFIG. 12B), such as the installation position coordinates of component P on board3that becomes the placing work target by component placing device1. Component information storage65stores component information that indicates the model number, dimension or the like of component P placed on board3. Installation height storage66stores the plurality of installation heights of the plurality of installation completion positions measured by installation position height measurer62.

Thrust-load correlation data acquirer67performs processing for acquiring the thrust-load correlation data illustrated inFIG. 11. In other words, as illustrated inFIG. 9, placing head11is accessed to load detector45prepared at a predetermined position of base1a, servo motor41of nozzle unit30which is a measurement target is driven with a prescribed thrust, and component holder31is pressed against load detecting device45aof load detector45, and load LF that corresponds to the thrust at this time is measured. The measurement result is transmitted to placing head controller13as the thrust-load correlation data and stored in first storage57that serves as the correlation data storage.

As described above, in the embodiment, placing head controller13is configured to include first storage57that serves as the correlation data storage and the above-described thrust limiter. Here, first storage57stores the correlation data indicating the relationship between the thrust of servo motor41and load LF generated at the tip end of component holder31for each of the plurality of servo motors. In addition, the thrust limiter sets thrust limit value TL for limiting the thrust generated by servo motor41based on the correlation data stored in first storage57and information on the load included in the command from main body controller14, and when lowering component holder31toward board3, thrust limiter has a function of limiting the thrust of servo motor41to be equal to or lower than thrust limit value TL. By providing placing head controller13having such a configuration, it is possible to stably control the installation load with high accuracy in the configuration having servo motor41for each of the plurality of component holders31.

Here, a component placing method for manufacturing the component placing board by creating the thrust-load correlation data illustrated inFIG. 11, by using placing head11including servo motor41that raises and lowers component holder31, and by placing the component on board3. In the component placing method, first, as illustrated inFIG. 9, load detector45for detecting the load is prepared and disposed below placing head11. Next, servo motor41is driven with a predetermined thrust, the lower end portion (nozzle31aor a load measuring jig installed instead of nozzle31a) of component holder31is pressed against load detector45, and the correlation data of thrust T of servo motor41and load LF is measured (refer toFIG. 10). Accordingly, characteristic straight line [L] illustrated inFIG. 11is acquired, and the measured correlation data is stored in first storage57which is the correlation data storage.

Next, limit load LFL applied to component P by component holder31when placing component P on board3and thrust limit value TL for limiting thrust T generated by servo motor41using the above-described correlation data are calculated. Limit load LFL is included in the control command transmitted from main body controller14to placing head controller13. When the component installation operation is started, component holder31which holds component P is lowered toward the installation position of board3.

In the lowering operation of component holder31, thrust T of servo motor41is limited to be equal to or lower than thrust limit value TL before component P lands at the installation position. In addition, after component P has landed at the installation position, component holder31is raised, component holder31is separated from component P that has landed at the installation position, and accordingly one component installation operation in the component placing method is completed. By using such a method, it is possible to set thrust limit value TL for limiting the thrust of servo motor41in accordance with limit load LFL by a simple method.

Next, with reference toFIG. 19, component installation processing executed by component placing device1having the above-described configuration. In addition, prior to the start of the processing illustrated inFIG. 19, board3of the work target is carried into board transporter2, positioned and held, and becomes in a state where board recognition is executed by board recognition camera16. When the component installation processing is started, first, placing head11is moved to component supplier5, component holder31is lowered, and component holder31holds component P which is the installation target (ST1). Next, placing head11in which component P is held by component holder31is moved to above component recognition camera12, and component P is recognized by imaging the component by component recognition camera12(ST2).

Next, component holder31is moved to installation position (ST3). In other words, installation work executer60of main body controller14controls XY table10based on installation data70illustrated inFIG. 12Bso as to position component holder31above the installation position of board3designated by the sequence of the installation work. Next, the deceleration height Dh (refer toFIG. 13) in the component installation operation for the installation position is calculated (ST4). The deceleration height calculation is executed only in a case where the installation height of the installation completion position in the vicinity of the installation position has already been measured as described above. In a case where the condition of the above-described deceleration height calculation is not satisfied, such as a case where newly transported board3is the target, the processing is skipped and the default deceleration height stored in advance is applied as it is.

Next, a component placing command is transmitted from main body controller14to placing head controller13(ST5). In other words, a control command including an installation operation parameter, such as a number that identifies component holder31in placing head11that serves as a work target, target height Th, deceleration height Dh, and limit load LFL, is transmitted to placing head controller13. In addition, the installation operation parameters are stored in first storage57and second storage58in order to execute the mounting operation in placing head11.

After this, the component installation operation by nozzle unit30of placing head11is executed by the control processing function of placing head controller13. In the component installation operation, servo motor41is driven by servo motor controller50(ST6), and accordingly, component holder31that holds component P is raised and lowered with respect to the installation position of board3. In addition, after the predetermined settling time has elapsed after the installation position of board3has landed, component holder31is raised, and accordingly, the component installation operation is completed (ST7).

In accordance with the completion of the operation, as a result of the thrust detection by thrust detector52of servo motor controller50in the component installation operation, the installation height of component holder31when installing component P detected by position detector53is transmitted to main body controller14(ST8). In addition, after this, it is determined whether or not the swinging occurs in the above-described component installation operation (ST9). In other words, in the lowering operation of component holder31, in a case where the thrust detected by thrust detector52has not reached the set thrust limit value TL, it is determined that the swinging in which component P held by component holder31has not landed on the board occurs, the fact is notified by notifier69, and the device is stopped (ST10).

In a case where it is determined that the swinging does not occur in (ST9), the installation height of component holder31received by main body controller14is stored in installation height stage66(ST11). Accordingly, component installation operation that considers component holder31of one nozzle unit30as a target is completed, and the presence and absence of component holder31that has not been completed yet is confirmed (ST12). Here, in a case where there is a component holder31of which the work has not been completed yet, the process returns to (ST3) and the subsequent processing is iteratively executed. On the other hand, in a case where there is no component holder31of which the work has not been completed yet, installation completion of all the components is confirmed (ST13). Here, in a case where the installation has not been completed, the process returns to (ST1) and the subsequent processing is iteratively executed. In addition, in (ST13), the installation completion of all of the components is confirmed, and the component installation processing by component placing device1is ended.

Next, a component placing method by component placing device1having the above-described configuration will be described with reference toFIGS. 14A to 17B. The plurality of component placing methods illustrated with reference to the drawings is executed by component placing device1including controller15for causing component holder31to perform the raising and lowering operation for placing component P held by component holder31at the installation position of board3by controlling servo motor41based on the preset operation pattern. Each operation illustrated in the component placing method is executed by controlling each portion illustrated inFIG. 8by controller15including placing head controller13and main body controller14, and accordingly, component placing board3* in which component P is placed on board3(refer toFIG. 12A) is manufactured.

In addition,FIGS. 14A to 17Bschematically illustrate the raising and lowering operation of component holder31in the component installation operation, and the vertical axis corresponds to the vertical displacement of component holder31and the horizontal axis corresponds to a passage of time, respectively. In addition, inFIGS. 14A to 17B, TR1indicated by a thick broken line indicates setting trajectory TR1where the lower end portion of component holder31moves in the preset operation pattern. In addition, TR2indicated by a bold solid line illustrates real trajectory TR2where the lower end portion of component holder31moves in the actual installation operation illustrated in each drawing.

In addition, in each drawing, timing ta is a timing of starting the operation, and indicates a state where component holder31is moved above the installation position of board3to stand by at standby height Z0. Thrust limit height TLh indicates the thrust limit starting height for limiting the thrust of servo motor41to be equal to or lower than thrust limit value TL when component holder31is lowered. Landing height ZC indicates the height of component holder31when a terminal of held component P is in contact with the solder part supplied to board3and component P lands. Further, target height Th1is a target height of the lowering operation of component holder31, and considering variation of the installation height of board3, target height Th1is set to be lower than the height at which component P actually lands.

First, with reference toFIGS. 14A and 14B, basic example M0of component installation operation by the component placing method will be described.FIG. 14Aillustrates high-speed installation mode M0-1in which component holder31is lowered only at high speed in order to shorten the work operation time in basic example M0. In addition,FIG. 14Billustrates low-impact installation mode M0-2in which the impact when component P held by component holder31lands is suppressed as much as possible in basic example M0.

With reference toFIG. 14A, high-speed installation mode M0-1will be described. Component holder31that holds component P moves above the installation position of board3and is in the standby state being positioned at standby height Z0at timing ta. Next, by the function of thrust limiter56provided in servo motor controller50, thrust limit value TL for limiting the thrust of servo motor41is set. Here, thrust limit value TL is set within a range in which the load that acts on component P from component holder31when driving servo motor41by the same thrust as thrust limit value TL is lower than biasing force FP by which biasing member33which is an elastic body biases component holder31.

Next, by controlling servo motor41based on the preset operation pattern, component holder31is lowered toward the installation position of board3with target height Th1as the target. In the middle of the lowering, the thrust of servo motor41is limited to be equal to or lower than thrust limit value TL before component P lands at the installation position at the timing when the height of component holder31reaches thrust limit height TLh.

In addition, setting of thrust limit value TL set by thrust limiter56provided in servo motor controller50, the thrust limiting of servo motor41at the timing of reaching thrust limit height TLh in the middle of lowering component holder31, and landing detection for detecting that component P has landed on board3, are similarly employed even in the first example, the second example, and the third example which are illustrated inFIGS. 15A, 15B, 16A, 16B, 17A, and 17B.

After this, when component holder31is further lowered, component holder31reaches landing height ZC, the terminal of held component P comes into contact with the solder portion supplied to board3, and a state where component P has landed is achieved. The impact at landing is absorbed by biasing member33, and after the impact is absorbed, biasing member33returns to the normal length before landing. After this, component holder31maintains the pressed state during target time Ts for statically setting the landing state of component P from a pressing start timing preset in the operation pattern. Then, component holder31starts to be raised and lowered at the raising start timing at which target time Ts time is up, component holder31is raised to standby height Z0and the installation operation ends.

In the above-described pressed state, since thrust limit value TL is set within the range of being smaller than biasing force FP before component P lands at the installation position, servo motor41presses component P to board3with the thrust smaller than biasing force FP. Therefore, compared to the method of the related art of pressing component P against board3by the elastic force of biasing member33elastically deformed by being pushed in after the landing, the installation load can be stably controlled with high accuracy in the low-load region.

Low-impact installation mode M0-2illustrated inFIG. 14Bis different from high-speed installation mode M0-1in that deceleration height Dh1between thrust limit height TLh and landing height ZC is set. In other words, in low-impact installation mode M0-2, when component holder31that holds component P reaches deceleration height Dh1in the process of being lowered from standby height Z0, the lowering speed is switched from high speed to low speed. Accordingly, the effect is obtained that component holder31is lowered to landing height ZC and the impact when component P lands is reduced.

In addition, in the process of the above-described installation operation, thrust detector52of servo motor controller50detects the thrust of servo motor41. Accordingly, swing detector61of servo motor controller50can detect that the thrust detected during the period until the raising start timing defined by the operation pattern after the thrust of servo motor41is limited has not reached thrust limit value TL. In this manner, the fact that the thrust after the thrust limiting does not reach thrust limit value TL means that there is a possibility that a “swing” state occurs in which component P held by component holder31does not land on board3. In a case where the state occurs, main body controller14notifies that the thrust of servo motor41has not reached thrust limit value TL by notifier69.

Next, with reference toFIGS. 15A and 15B, first example M1of component installation operation by the component placing method will be described. In basic example M0illustrated inFIGS. 14A and 14B, component holder31is raised according to a raising timing determined by the predetermined operation pattern. On the other hand, in the first example M1, the elapsed time after component P held by component holder31has landed is measured, and the raising timing of component holder31is determined.

The technical significance of applying such a first embodiment M1will be described. In other words, in a case where the height of the installation position varies due to deformation of the board, the landing height at which component P comes into contact with the solder portion of the board also varies. In such a case, the timing at which component P lands in the installation operation is also not constant. Therefore, it is not possible to appropriately ensure the time for pressing component P against the solder portion, and it is difficult to ensure an appropriate solder bonding quality. In particular, in a case where the pressing time is extremely long, there is a concern that troubles, such as bridges to which solder is connected between adjacent lands or solder balls in a state where particulate solder is separated. Even in a case where the height of the installation position varies in this manner, by applying first embodiment M1illustrated in the embodiment, it is possible to appropriately ensure the time for pressing component P against the solder portion.

FIG. 15Aillustrates high-speed installation mode M1-1in which component holder31is lowered only at high speed in order to shorten the work operation time in first example M1. In addition,FIG. 15Billustrates low-impact installation mode M1-2in which the impact when component P held by component holder31lands is suppressed as much as possible in first example M1.

With reference toFIG. 15A, high-speed installation mode M1-1will be described. Component holder31that holds component P moves above the installation position of board3and is in the standby state being positioned at standby height Z0at timing ta. Next, by controlling servo motor41based on the preset operation pattern, component holder31is lowered toward the installation position of board3with target height Th1as the target.

Prior to the lowering, thrust limit value TL for limiting the thrust of servo motor41is set similarly to basic example M0illustrated inFIGS. 14A and 14B. In addition, in the middle of the lowering of component holder31, the thrust of servo motor41is limited to be equal to or lower than thrust limit value TL before component P lands at the installation position similar to basic example M0illustrated inFIGS. 14A and 14B. By the thrust limiting, the same effect as the effect described in basic example M0illustrated inFIGS. 14A and 14Bis obtained.

After this, when component holder31is further lowered, component holder31reaches landing height ZC. Accordingly, the terminal of held component P comes into contact with the solder portion supplied to board3, and component P lands on board3. The landing is detected by the function of landing detector54provided in servo motor controller50by any of the following methods.

First, one method is performed by monitoring the thrust of servo motor41by thrust detector52in servo motor controller50. In other words, the thrust of servo motor41of which the thrust is limited to be equal to or lower than thrust limit value TL has reached set thrust limit value TL, it is detected that component P has landed on board3. Another method of landing detection is a method based on the position signal from servo motor41. In other words, in a case where the encoder pulse output from encoder44of servo motor41, it is detected that the component has landed on board3.

When the landing of component P is detected by any of the above-described methods in this manner, the elapsed time after timing t1at which the landing is detected by the timing function of timer55is measured. In addition, when the elapsed time measured by timer55reaches target time Ts before the raising start timing defined by the operation pattern indicated by setting trajectory TR1, servo motor41is controlled at timing t2to raise component holder31.

Accordingly, even in a case where board3of which landing height ZC varies due to deformation or the like is targeted, it is always possible to press component P to the solder portion at appropriate target time Ts, and to prevent a solder joint failure caused by variation of the elapsed time. Furthermore, it is possible to prevent the delay of the installation operation time due to unnecessarily long pressing time, and to improve the productivity.

Low-impact installation mode M1-2illustrated inFIG. 15Bis different from high-speed installation mode M1-1in that deceleration height Dh1between thrust limit height TLh and landing height ZC is set. In other words, in low-impact installation mode M1-2, when component holder31that holds component P reaches deceleration height Dh1in the process of being lowered from standby height Z0, the lowering speed is switched from high speed to low speed. Accordingly, the effect is obtained that component holder31is lowered to landing height ZC and the impact when component P lands is reduced.

Next, with reference toFIGS. 16A and 16B, second example M2of component installation operation by the component placing method will be described. In second example M2, installation position height measurer62measures the installation height at the installation position during the installation operation of placing component P by allowing component P held by component holder31to land. In this manner, by measuring the installation height at the installation position during the installation operation, the board height information can be acquired by a simple method without separately performing the measuring operation for board height measurement.

FIG. 16Aillustrates high-speed installation mode M2-1in which component holder31is lowered only at high speed in order to shorten the work operation time in second example M2. In addition,FIG. 16Billustrates low-impact installation mode M2-2in which the impact when component P held by component holder31lands is suppressed as much as possible in second example M2.

With reference toFIG. 16A, high-speed installation mode M2-1will be described. Component holder31that holds component P moves above the installation position of board3and is in the standby state being positioned at standby height Z0at timing ta. Next, by controlling servo motor41based on the preset operation pattern, component holder31is lowered toward the installation position of board3with target height Th1as the target.

Prior to the lowering, thrust limit value TL for limiting the thrust of servo motor41is set similarly to basic example M0illustrated inFIGS. 14A and 14B. In addition, in the middle of the lowering of component holder31, the thrust of servo motor41is limited to be equal to or lower than thrust limit value TL before component P lands at the installation position similar to basic example M0illustrated inFIGS. 14A and 14B. By the thrust limiting, the same effect as the effect described in basic example M0illustrated inFIGS. 14A and 14Bis obtained.

After this, when component holder31is further lowered, component holder31reaches landing height ZC. Accordingly, the terminal of held component P comes into contact with the solder portion supplied to board3, and component P lands on board3. The landing is detected by the function of landing detector54provided in servo motor controller50and measures the elapsed time from timing t1when the landing is detected by the timing function of timer55. In addition, when the elapsed time measured by timer55reaches target time Ts before the raising start timing defined by the operation pattern indicated by setting trajectory TR1, servo motor41is controlled at timing t2to raise component holder31.

In other words, in the above-described installation operation, after component P has landed at the installation position of board3, component holder31is raised, and component holder31is separated from component P that has landed at the installation position of board3. In addition, at least during the period from the landing of component P to the installation position of board3until before component holder31starts to be raised, the thrust of servo motor41is limited. The pressing by component holder31for installing component P is performed in a state where the thrust of servo motor41is limited.

In second example M2illustrated in the embodiment, the installation height is detected during the above-described installation operation. In other words, at a predetermined timing from the time when component P has landed at the installation position of board3to immediately before component holder31starts to be raised, installation position height measurer62acquires the positional information of component holder31from position detector53. The positional information of component holder31acquired at the timing is the landing height ZC that indicates the position in the height direction of component holder31inFIG. 13. In addition, installation position height measurer62calculates the installation height of the installation position at which component P is installed, based on the acquired positional information and the dimension of the installed component P. In other words, installation position height measurer62obtains installation height Z1based on landing height ZC and installation thickness dimension d including the thickness of component P in component P.

In addition, the timing at which installation position height measurer62acquires the positional information of component holder31from position detector53is within the period after biasing member33which is the elastic body absorbs the impact when component P lands at the installation position, until immediately before component holder31starts to be raised, and is most preferably immediately before the start of the raising. Since acquisition of the positional information is performed in a state where buffering biasing member33fully extends, even in a case where buffering biasing member33is provided, it is possible to perform the height detection of component holder31from the positional information of position detector53with high accuracy.

Furthermore, since load LF at which component holder31presses board3is a low load, the deformation of board3is small. Therefore, even when the height of the installation position is measured using the height position of component holder31, the error is small and accurate height measurement can be performed. Accordingly, it is possible to acquire board height information including the height of the installation position by a simple method concurrently with execution of the component installation operation without using a dedicated measurement device.

Low-impact installation mode M2-2illustrated inFIG. 16Bis different from high-speed installation mode M2-1in that deceleration height Dh1between thrust limit height TLh and landing height ZC is set. In other words, in low-impact installation mode M2-2, when component holder31that holds component P reaches deceleration height Dh1in the process of being lowered from standby height Z0, the lowering speed is switched from high speed to low speed. Accordingly, the effect is obtained that component holder31is lowered to landing height ZC and the impact when component P lands is reduced.

Next, with reference toFIGS. 17A and 17B, third example M3of component installation operation by the component placing method will be described. In third example M3, during the installation operation of placing component P by allowing component P held by component holder31to land, the installation height at the installation completion position at which the component is installed is detected, and based on the detected installation height, the deceleration height when installing the component to the uninstallation position is calculated and corrected.

FIG. 17Aillustrates pre-correction installation mode M3-1in which the component installation operation is performed in a state where the installation completion position has not yet existed and the deceleration height is not corrected in third example M3. In addition,17B illustrates post-correction installation mode M3-2in which the installation height at the installation completion position is detected in third example M3, the deceleration height is corrected based on the detected installation height, and then the component is installed.

With reference toFIG. 17A, pre-correction installation mode M3-1will be described. Component holder31that holds component P moves above the installation position of board3and is in the standby state being positioned at standby height Z0at timing ta. Next, by controlling servo motor41based on the preset operation pattern, component holder31is lowered toward the installation position of board3with target height Th1as the target. Here, the operation pattern includes deceleration height Dh1for decelerating the speed of lowering component holder31and target height Th1which is a target of component holder31. When lowering component holder31, component holder31is lowered at high speed up to deceleration height Dh1and at low speed from deceleration height Dh1. In pre-correction installation mode M3-1, deceleration height Dh1is set to be a height of Δh1from target height Th1.

Prior to the lowering, thrust limit value TL for limiting the thrust of servo motor41is set similarly to basic example M0illustrated inFIGS. 14A and 14B. In addition, in the middle of the lowering of component holder31, the thrust of servo motor41is limited to be equal to or lower than thrust limit value TL before component P lands at the installation position similar to basic example M0illustrated inFIGS. 14A and 14B. By the thrust limiting, the same effect as the effect described in basic example M0illustrated inFIGS. 14A and 14Bis obtained.

After this, when component holder31is further lowered, component holder31reaches landing height ZC. Accordingly, the terminal of held component P comes into contact with the solder portion supplied to board3, and component P lands on board3. The landing is detected by the function of landing detector54provided in servo motor controller50and measures the elapsed time from timing t1when the landing is detected by the timing function of timer55. In addition, when the elapsed time measured by timer55reaches target time Ts before the raising start timing defined by the operation pattern indicated by setting trajectory TR1, servo motor41is controlled at timing t2to raise component holder31and separate component holder31from component P that has landed at the installation position. In addition, one installation operation is completed at timing tb when component holder31is raised to standby height Z0. In pre-correction installation mode M3-1, work time WT1is required from timing ta to timing tb for one installation operation.

In order to improve the productivity by shortening work time WT1as much as possible, in third example M3illustrated in the embodiment, during the above-described installation operation, detection of the installation height for the purpose of correcting the deceleration height is performed. In other words, at a predetermined timing from the time when component P has landed at the installation position of board3to immediately before component holder31starts to be raised, installation position height measurer62acquires the positional information (landing height ZC) of component holder31from position detector53.

In addition, based on acquired landing height ZC and the dimension of installed component P, installation height measuring processing is performed to calculate the installation height indicating the height at the installation completion position which is the installation position at which component P is installed. The installation height measurement processing is executed by installation position height measurer62of main body controller14. In other words, inFIG. 13, installation height Z1is obtained based on landing height ZC indicating the position of component holder31in the height direction and installation thickness dimension d including the thickness of component P in component P.

Then, similar installation height measurement processing is performed for the plurality of installation completion positions, and the plurality of installation heights are stored in installation height storage66of main body controller14. Next, using at least one installation height stored in installation height storage66to calculate the deceleration height when the component is installed at an uninstallation position which is an installation position where the component has not yet been installed. The calculation processing is executed by deceleration height computer63of the main body controller14.

The deceleration height calculation processing is illustrated in the execution example of the deceleration height correction by deceleration height computer63described with reference toFIGS. 18A and 18B. In other words, in the example illustrated inFIG. 18A, deceleration height computer63computes the deceleration height based on the installation height of the installation completion position that exists within the range preset from the uninstallation position. In other words, in the example illustrated inFIG. 18B, deceleration height computer63computes the deceleration height of the uninstallation position based on the installation height of the preset number of installation completion positions. Accordingly, instead of deceleration height Dh1before correction, corrected deceleration height Dh2computed based on the installation height of the installation completion position is obtained.

FIG. 17Billustrates post-correction installation mode M3-2in which component P is installed at the uninstallation position based on corrected deceleration height Dh2computed in this manner. In the example illustrated here, deceleration height Dh2after the correction is set to the height of Δh2from target height Th1. Here, Δh2is set based on the installation height of the known installation completion position, and thus, Δh2can be set to an appropriate value smaller than Δh1.

Therefore, it is possible to set the corrected deceleration height Dh2to a height closer to landing height ZC, and to prevent a delay at the lowering time due to deceleration from an unnecessarily high position. Accordingly, in pre-correction installation mode M3-1, work time WT1is required from timing ta to timing tb for one installation operation, and meanwhile, in post-correction installation mode M3-2, the required time from timing ta to timing tb is shortened to work time WT2shorter than WT1. Even in a case where the board on which the curvature deformation state varies in this manner is a target, the productivity can be improved by appropriately setting the deceleration height based on the installation height of the installation completion position.

In addition, in the embodiment, the installation thickness dimension d used in the calculation of installation height Z1by installation position height measurer62and the calculation of the deceleration height Dh2by deceleration height computer63is a thickness dimension obtained by adding the thickness of component P and the thickness of land3c, but both the thickness of land3cand the thickness of joining solder S or any of the thickness of land3cand the thickness of joining solder S may be used as installation thickness dimension d. In a case of ignoring both the thickness of land3cand the thickness of joining solder S, the thickness of component P may be used as the installation thickness dimension d. In other words, the installation thickness dimension d includes at least the thickness of component P.

The component placing device and the component placing method of the disclosure have the effect that the installation load can be stably controlled with high precision in the low-load region and are useful in the field where the component is placed at the installation position of the board.