JP6643894B2 - Mounting head cleaning apparatus and mounting head cleaning method - Google Patents

Description

The present invention relates to a mounting head cleaning apparatus and a mounting head cleaning method for a mounting head used in a component mounting machine that produces an electronic circuit product.

The component mounter sucks an electronic component at a supply position by a suction nozzle, and mounts the electronic component at a predetermined coordinate position on a circuit board. The suction nozzle sucks the electronic component by negative pressure air supplied through an air passage formed inside the mounting head. Therefore, dust may be sucked into the air passage from the tip of the suction nozzle. The air passage of the mounting head is cleaned using, for example, a cleaning device disclosed in Patent Document 1.

Patent Document 1: Japanese Patent Application Laid-Open No. 2011-3679

In cleaning the air passage of the mounting head, it is desired to remove dust more reliably and to reduce the work time required for cleaning. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a mounting head cleaning apparatus and a mounting head cleaning method that can improve the cleaning efficiency of an air passage for a mounting head.

A mounting head cleaning device according to the present invention includes a suction nozzle that suctions a component by negative pressure air supplied from a negative pressure air supply device via an air passage, and a detachable holding of the suction nozzle, and a lifting mechanism that moves up and down. The air passage formed inside the mounting head is cleaned for a mounting head including a nozzle shaft that is rotatably and rotatably held by a rotation mechanism. The mounting head cleaning device includes a clamp mechanism to which the mounting head detached from the component mounting machine is fixed, a cleaning fluid supply device that supplies a cleaning fluid including positive pressure air or oil mist to the air passage, In the cleaning process using the fluid supply device, the operation of the elevating mechanism and the rotation of the nozzle shaft are performed so that the nozzle shaft is moved up and down and the nozzle shaft is rotated around an axis in synchronization with the elevating operation of the nozzle shaft. A control device for controlling the operation of the mechanism. The cleaning fluid is the oil mist. The cleaning process includes an idling step of raising and lowering the nozzle shaft in a state where the flow of the cleaning fluid in the air passage is shut off. In the idling step, the control device rotates the nozzle shaft around an axis in synchronization with the elevating operation of the nozzle shaft.
A mounting head cleaning device according to the present invention includes a suction nozzle that suctions a component by negative pressure air supplied from a negative pressure air supply device via an air passage, and a detachable holding of the suction nozzle, and a lifting mechanism that moves up and down. The air passage formed inside the mounting head is cleaned for a mounting head including a nozzle shaft that is rotatably and rotatably held by a rotation mechanism. The mounting head cleaning device includes a clamp mechanism to which the mounting head detached from the component mounting machine is fixed, a cleaning fluid supply device that supplies a cleaning fluid including positive pressure air or oil mist to the air passage, In the cleaning process using the fluid supply device, the operation of the elevating mechanism and the rotation of the nozzle shaft are performed so that the nozzle shaft is moved up and down and the nozzle shaft is rotated around an axis in synchronization with the elevating operation of the nozzle shaft. A control device for controlling the operation of the mechanism. A dummy nozzle closing the open end of the air passage is mounted on the nozzle shaft in place of the suction nozzle. The control device supplies the negative pressure air to the air passage to reduce the pressure of the air passage, or supplies the positive pressure air to the air passage to increase the pressure of the air passage. At this time, the nozzle shaft is rotated around the axis in synchronization with the elevating operation of the nozzle shaft.

The mounting head cleaning method according to the present invention includes a suction nozzle that sucks a component by negative pressure air supplied through an air passage by a negative pressure air supply device, the suction nozzle being detachably held, and a lifting mechanism that moves up and down. The air passage formed inside the mounting head is cleaned, with the mounting head including a nozzle shaft rotatably and rotatably held by a rotation mechanism. In the mounting head cleaning method, in a cleaning process using a cleaning fluid supply device that supplies a cleaning fluid including positive pressure air or oil mist to the air passage, the lifting mechanism operates so that the nozzle shaft is raised and lowered. A nozzle shaft elevating step; and a nozzle axis rotating step in which the rotating mechanism operates so that the nozzle axis is rotated around an axis in synchronization with the elevating operation of the nozzle axis in the nozzle axis elevating step.

According to the above configuration , in the cleaning process using the cleaning fluid supply device, the mounting head is rotated around the axis of the nozzle axis in synchronization with the elevating operation of the nozzle axis. Here, the nozzle shaft is held so as to be able to move up and down and rotate on the main body of the mounting head. Therefore, the air passage communicating the main body of the mounting head and the nozzle shaft changes with the vertical movement and rotation of the nozzle shaft. Therefore, by rotating the nozzle shaft around the axis while moving up and down in the cleaning process, the portion to be cleaned in the air passage is prevented from being partially biased. Therefore, the cleaning efficiency is improved, and the time required for the cleaning process is reduced.

FIG. 1 is an overall view showing a component mounting machine including a mounting head. FIG. 2 is a diagram illustrating a mounting head in FIG. 1. FIG. 3 is a cross-sectional view illustrating an air passage of a mounting head. FIG. 4 is a diagram illustrating a state in which the mounting head is attached to a moving table or a mounting head cleaning device. 1 is an overall view showing a mounting head cleaning device according to an embodiment. It is a fluid supply circuit diagram comprised by a cleaning fluid supply device. FIG. 4 is a block diagram illustrating a control device of the mounting head cleaning device. It is a flowchart which shows a cleaning process. It is a flowchart which shows the cleaning process in a cleaning process. It is a flowchart which shows the blowing process in a cleaning process. It is a flowchart which shows the idling process in a cleaning process.

Hereinafter, an embodiment of a mounting head cleaning apparatus and a mounting head cleaning method according to the present invention will be described with reference to the drawings. The mounting head cleaning apparatus cleans an air passage formed inside the mounting head for a mounting head used in a component mounting machine that produces an electronic circuit product.

A component mounter is a device for mounting a plurality of electronic components on a circuit board. On the circuit board, cream solder is applied to a mounting position of the electronic component by, for example, a screen printing machine, and the electronic component is mounted by being sequentially transported through a plurality of component mounters. Thereafter, the circuit board on which the electronic components are mounted is conveyed to a reflow furnace and soldered to be a circuit board product.

<Embodiment> (1. Configuration of Component Mounter) The configuration of the component mounter 1 will be described with reference to FIGS. The component mounter 1 includes a board transfer device 10, a component supply device 20, and a component transfer device 30. Each of the devices 10, 20, 30 is provided on the base 2 of the component mounter 1. As shown in FIG. 1, the horizontal width direction of the component mounter 1 (the direction from the upper left to the lower right in FIG. 1) is the X-axis direction, and the horizontal longitudinal direction of the component mounter 1 (from the upper right to the lower left in FIG. 1). A direction toward the head is defined as a Y-axis direction, and a vertical height direction (a vertical direction in FIG. 1) is defined as a Z-axis direction.

(1-1. Board Transfer Apparatus 10) The board transfer apparatus 10 transfers the circuit board B in the X-axis direction and positions the circuit board B at a predetermined position. The substrate transfer device 10 is of a double conveyor type including a plurality of transfer mechanisms 11 arranged in parallel in the Y-axis direction. The transport mechanism 11 has a pair of guide rails 12 and 13 that guide the circuit board B placed and transported on a not-shown conveyor belt. The transport mechanism 11 carries in the circuit board B to a predetermined position in the X-axis direction during the mounting process of the electronic component, and clamps the circuit board B by a clamp device. Then, when the electronic component is mounted on the circuit board B, the transport mechanism 11 unclamps the circuit board B and carries the circuit board B out of the component mounter 1.

(1-2. Component Supply Device 20) The component supply device 20 is a device that supplies an electronic component mounted on the circuit board B. The component supply device 20 is arranged on the front side (lower left side in FIG. 1) of the component mounter 1 in the Y-axis direction. In this embodiment, the component supply device 20 is of a feeder type using a plurality of cassette type feeders 21. The feeder 21 has a feeder body 21a detachably attached to the base 2, and a reel housing 21b provided on the rear end side of the feeder body 21a. The feeder 21 holds the supply reel 22 on which the component packaging tape is wound by the reel housing 21b.

The component packaging tape includes a carrier tape in which electronic components are stored at a predetermined pitch, and a top tape that is adhered to an upper surface of the carrier tape and covers the electronic components. The feeder 21 pitch-feeds the component packaging tape drawn from the supply reel 22 by a pitch feed mechanism (not shown). Then, the feeder 21 peels off the top tape from the carrier tape to expose the electronic components. Thus, the feeder 21 supplies the electronic component so that the suction nozzle 46 of the component transfer device 30 can suck the electronic component at the supply position located on the front end side of the feeder main body 21a.

(1-3. Component Transfer Device 30) The component transfer device 30 holds the electronic component supplied to the supply position and transfers the electronic component to the mounting position on the circuit board B. In the present embodiment, the component transfer device 30 is of a rectangular coordinate type disposed above the substrate transfer device 10 and the component supply device 20. In this component transfer device 30, a Y-axis slide 32 is provided on a pair of Y-axis rails 31 extending in the Y-axis direction so as to be movable in the Y-axis direction.

The Y-axis slide 32 is controlled by the operation of a Y-axis motor 33 via a ball screw mechanism. The Y-axis slide 32 is provided with a movable table 34 movably in the X-axis direction. The moving table 34 is controlled by the operation of an X-axis motor 35 via a ball screw mechanism (not shown). The Y-axis slide 32 and the moving table 34 may be provided in a linear motion mechanism using a linear motor, for example, and may be configured to be controlled by the operation of the linear motor.

A board camera 36 that captures an image of a reference mark (not shown) of the circuit board B is attached to the movable table 34 of the component transfer device 30. The board camera 36 is fixed to the movable base 34 so that the optical axis is in the Z-axis direction. The image data obtained by the imaging by the board camera 36 includes, for example, a board mark (not shown) attached to the circuit board B, and is used for recognizing a positioning state of the circuit board B.

The mounting head 40 is detachably attached to the moving table 34 of the component transfer device 30. As shown in FIG. 2, the mounting head 40 has a head main body 41 that is clamped to the moving table 34. The head body 41 rotatably supports an index shaft 43 whose rotation angle is determined by a predetermined angle by an R-axis motor 42. At the lower end of the index shaft 43, a rotary head 44 is fixed.

The rotary head 44 holds a plurality of (for example, 12) nozzle shafts 45 at equal intervals in the circumferential direction on a circle concentric with the R axis so as to be slidable and rotatable in the Z axis direction. The nozzle shaft 45 is urged upward with respect to the rotary head 44 by the elastic force of a spring (not shown). Thereby, the nozzle shaft 45 is located at the rising end in the normal state where no external force is applied.

At the lower end of the nozzle shaft 45, a suction nozzle 46 is detachably held. The suction nozzle 46 suctions a component by negative pressure air supplied from a negative pressure air supply device (not shown) via an air passage 60. The detailed configuration of the air passage 60 will be described later. The plurality of suction nozzles 46 are moved to a predetermined angular position around the R-axis (for example, the vertical position of the nozzle shaft 45) by rotating the rotary head 44 via the index shaft 43 in accordance with the driving of the R-axis motor 42. Indexed sequentially.

The rotating body 49 integrally formed with the driven gear 47 and the θ-axis gear 48 is arranged on the outer peripheral side of the index shaft 43 so as to be rotatable relative to the index shaft 43. A θ-axis motor 51 is fixed to the head main body 41. The drive gear 52 fixed to the output shaft of the θ-axis motor 51 meshes with the driven gear 47. The θ-axis gear 48 is formed so as to have a predetermined tooth width in the axial direction (R-axis direction) of the rotating body 49.

A nozzle gear 53 is formed at the upper end of the nozzle shaft 45. The nozzle gear 53 is meshed slidably in the R-axis direction with a θ-axis gear 48 supported on the outer peripheral side of the index shaft 43 so as to be relatively rotatable. The driven gear 47, the θ-axis gear 48, the θ-axis motor 51, the drive gear 52, and the nozzle gear 53 constitute a rotation mechanism in the mounting head 40. The nozzle shaft 45 and the suction nozzle 46 are integrally rotated (rotated) around the θ axis by the operation of the above-described rotation mechanism, and the rotation angle and the rotation speed are controlled.

Further, the head main body 41 is provided with a nozzle operating member 54. The nozzle operating member 54 is slidably guided in the up-down direction (Z-axis direction) by a guide bar 55. The Z-axis motor 56 fixed to the head main body 41 drives the ball screw mechanism 57. The nozzle operating member 54 is moved up and down in the Z-axis direction by driving the ball screw mechanism 57.

The nozzle operating member 54 has a nozzle lever 58 that comes into contact with the upper end of the nozzle shaft 45 indexed to the above-described elevating position among the plurality of nozzle shafts 45. The nozzle lever 58 descends as the nozzle operating member 54 moves downward in the Z-axis direction, and presses the abutting nozzle shaft 45 downward in the Z-axis direction. The nozzle operating member 54, the guide bar 55, the Z-axis motor 56, the ball screw mechanism 57, and the nozzle lever 58 constitute a lifting mechanism of the mounting head 40. The nozzle shaft 45 and the suction nozzle 46 are integrally moved up and down in the Z-axis direction by the operation of the above-mentioned elevating mechanism, and the position and the moving speed in the Z-direction are controlled.

As shown in FIG. 1, a component camera 5 is fixed to the base 2 so that the optical axis is in the Z-axis direction. The component camera 5 is configured to be able to image the electronic component held by the suction nozzle 46. The component camera 5 captures an image of the electronic component while the mounting head 40 moves from the component supply position of the component supply device 20 to the electronic component mounting position on the circuit board B. The component mounter 1 recognizes the holding state of the electronic component by the suction nozzle 46 based on the image data obtained by the imaging of the component camera 5. The component mounter 1 corrects the operation of the mounting head 40 according to the holding state of the electronic component, thereby improving the accuracy of the mounting control.

(1-4. Detailed Configuration of Air Passage 60) Inside the mounting head 40, an air passage 60 that supplies negative pressure air generated by a negative pressure air supply device (not shown) of the component mounter 1 to the suction nozzle 46. Are formed. The air passage 60 has an in-shaft passage 61 and an in-head passage 62 as shown in FIG. The air passage 60 has an introduction passage 63 and a connection pipe 64 as shown in FIG.

As shown in FIG. 3, the axial passage 61 is formed by connecting a pipe extending in the axial direction at the center of the nozzle shaft 45 and an annular groove formed on the outer peripheral side of the nozzle shaft 45. . The in-head passage 62 is formed inside the rotary head 44 so that the negative pressure air supplied to the rotary head 44 can be distributed to each nozzle shaft 45. The passage 62 in the head is connected to the above-described annular groove in the passage 61 in the shaft so that negative pressure air or the like can flow therethrough.

The mounting head 40 includes a mechanical switching valve (hereinafter, referred to as a mechanical valve) 65, a stepping motor 66, and an operating shaft 67. The mechanical valve 65 is a member that switches between supplying and shutting off the negative pressure air to the nozzle shaft 45. The same number of mechanical valves 65 as the number of nozzle shafts 45 held by the rotary head 44 are arranged on the rotary head 44. The mechanical valve 65 is fitted to the rotary head 44 so as to be slidable in the vertical direction.

At the upper end of the mechanical valve 65, an engagement portion 65a is formed at a portion protruding from the upper surface of the rotary head 44. The stepping motor 66 is fixed to the mounting head 40. The operation shaft 67 is moved up and down by a predetermined amount by driving the stepping motor 66. The engaging portion 65a of the mechanical valve 65 is configured to be detachable around the R axis and engageable in the Z axis direction with the engaging portion 65a of the operating shaft 67. As a result, the engagement portions 65a of the plurality of mechanical valves 65 are sequentially engaged with the engagement portions 67a of the operating shaft 67 by determining the rotation angle of the rotary head 44.

The mechanical valve 65 is held by the rotary head 44 with a certain frictional force. That is, the mechanical valve 65 is restricted from sliding in the vertical direction due to its own weight. Therefore, the mechanical valve 65 is held at the rising end position or the falling end position unless an external force exceeding the frictional force is applied.

As shown in FIG. 3, the mechanical valve 65 is turned off by moving to the lower end position, and shuts off the introduction of the negative pressure air supplied into the mounting head 40 into the axial passage 61 of the nozzle shaft 45. On the other hand, the mechanical valve 65 is turned ON by moving to the rising end position, and allows the introduction of the negative pressure air supplied into the mounting head 40 into the in-shaft passage 61 of the nozzle shaft 45.

The in-head passage 62 of the rotary head 44 is connected to an introduction passage 63 formed in the head main body 41. As shown in FIG. 4, the introduction passage 63 is connected via the connection conduit 64 when the rotary head 44 is attached to the moving table 34 of the component transfer device 30 or the main body of the mounting head cleaning device 70 described later. To introduce negative pressure air. The connection pipe 64 is connected to a supply pipe 88 provided on the movable table 34 or the main body of the mounting head cleaning device 70.

(2. Configuration of Mounting Head Cleaning Device) (2-1. Overall Configuration of Mounting Head Cleaning Device 70) The configuration of the mounting head cleaning device 70 will be described with reference to FIGS. The mounting head cleaning device 70 is a device for cleaning the air passage 60 formed inside the mounting head 40. The mounting head cleaning device 70 can adopt either a configuration provided inside the component mounter 1 or a configuration provided as an external device separate from the component mounter 1. Here, as shown in FIG. 5, a mode in which the mounting head cleaning device 70 is an external device is illustrated.

The mounting head 40 including the rotary head 44 (see FIG. 2) is attached to the mounting head cleaning device 70. The mounting head cleaning device 70 has a clamp mechanism 71 to which the mounting head 40 removed from the component mounter 1 is fixed. The clamp mechanism 71 has the same configuration as a clamp mechanism (not shown) that clamps the mounting head 40 to the moving table 34 of the component mounting machine 10.

As shown in FIG. 4, the clamp mechanism 71 mounts with the leg 41 a formed at the lower part of the mounting head 40 engaged with the leg support 72 formed on the main body of the mounting head cleaning device 70. The upper part of the head 40 is fixed. Thus, the mounting head 40 is positioned and fixed to the main body of the mounting head cleaning device 70. As a result, the connection pipe 64 of the mounting head 40 is connected to the supply pipe 88 of the mounting head cleaning device 70, and the flow of the negative pressure air or the cleaning fluid becomes possible.

Further, as shown in FIG. 5, the mounting head cleaning device 70 is provided with a suction blower 73 that suctions a cleaning fluid used for cleaning the air passage 60 of the mounting head 40. The oil and dust collected by the suction blower 73 are collected in a collection box 74 provided below the suction blower 73. The mounting head 40 is connected to electrical and communication connectors while being fixed to the mounting head cleaning device 70. Thereby, the mounting head 40 can control each motor and the like by the control device 90 of the mounting head cleaning device 70.

(2-2. Cleaning Fluid Supply Device 80) The mounting head cleaning device 70 includes a cleaning fluid supply device 80 that supplies a cleaning fluid composed of positive pressure air or oil mist to the air passage 60 of the mounting head 40. The cleaning fluid supply device 80 forms the fluid supply circuit shown in FIG. In the cleaning fluid supply device 80, a compressor 81, which is a supply source of positive pressure air, is connected to an air supply passage. A regulator valve 83 for adjusting the pressure of the air supply passage 82 is disposed in the air supply passage 82.

The air supply passage 82 is configured to be selectively connected to a cleaning air passage 85 and a cleaning oil passage 86 via a cleaning switching valve 84. The cleaning air passage 85 and the cleaning oil passage 86 are connected before the supply pipe 88. A lubricator 87 is disposed in the cleaning oil passage 86. The lubricator 87 supplies mist-like oil to the cleaning oil passage 86 to which the positive-pressure air is being supplied. As a result, oil mist is generated in the cleaning oil passage 86. As the oil supplied by the lubricator 87, for example, a mixture of a fluorine oil and a volatile solvent is used.

In the above-described configuration, when the cleaning air passage 85 is connected to the air supply passage 82 by switching the cleaning switching valve 84, positive pressure air is supplied to the supply pipe 88 as a cleaning fluid. On the other hand, when the cleaning oil passage 86 is connected to the air supply passage 82 by switching the cleaning switching valve 84, an oil mist is fed into the supply pipe 88 as a cleaning fluid. The supply pipe 88 is connected to the connection pipe 64 of the mounting head 40 attached to the main body of the mounting head cleaning device 70 so that a cleaning fluid can be supplied. With such a configuration, a cleaning fluid composed of positive pressure air or oil mist is supplied to the air passage 60 of the mounting head 40.

A suction blower 73 (see FIG. 6) is connected to the air supply passage 82 via a suction valve 89. The suction valve 89 is switched when the mounting head 40 is washed. Thus, the cleaning fluid discharged from the tip of the suction nozzle 46 of the mounting head 40 is sucked by the suction blower 73. As described above, the mounting head cleaning device 70 is configured to prevent the cleaning fluid used for cleaning from scattering around.

(2-3. Control Device 90) The mounting head cleaning device 70 includes a control device 90 that controls the operations of the mounting head 40 and the cleaning fluid supply device 80 in the cleaning processing using the cleaning fluid supply device 80. As shown in FIG. 7, the control device 90 includes a cleaning control unit 91, a storage unit 92, an input / output interface 93, and a motor control circuit 94.

The cleaning control unit 91 is mainly configured by a CPU. The cleaning control unit 91 performs cleaning switching of the motors 42, 51, 56, 66 of the mounting head 40 and the cleaning fluid supply device 80 based on a cleaning program stored in advance and signals output from various sensors (not shown). The operation of the valve 84 and the like is controlled. The storage unit 92 is configured by an optical drive device, a flash memory, or the like. The storage unit 92 stores various control data including a cleaning program.

The cleaning control unit 91, the storage unit 92, the motor control circuit 94, and various sensors are connected to the input / output interface 93 via a bus. The input / output interface 93 is interposed between the cleaning control unit 91 and the storage unit 92 and the motor control circuit 94, and adjusts data format conversion and signal strength. The motor control circuit 94 controls the R-axis motor 42, the θ-axis motor 51, the Z-axis motor 56, and the stepping motor 66 of the mounting head 40 attached to the mounting head cleaning device 70.

(3. Cleaning Process by Mounting Head Cleaning Device) The configuration of the cleaning process of the mounting head 40 by the mounting head cleaning device 70 will be described with reference to FIGS. 6 and 8 to 11. The mounting head 40 is attached to the main body of the mounting head cleaning device 70 with all the suction nozzles 46 removed from the nozzle shaft 45 during the cleaning process. When the mounting head 40 is attached, the connection pipe 64 of the mounting head 40 is connected to the supply pipe 88 of the mounting head cleaning device 70.

Thus, the mounting head cleaning device 70 is in a state where it is possible to supply the cleaning fluid composed of positive pressure air or oil mist from the cleaning fluid supply device 80 to the air passage 60 of the mounting head 40. The mounting head 40 and the mounting head cleaning device 70 are connected to connectors of an electric system and a communication system. Thus, the mounting head cleaning device 70 is in a state where the control device 90 can control each motor of the mounting head 40 and the like.

(3-1. Outline of Cleaning Process) In the present embodiment, a cleaning process using an oil mist will be exemplified. In the cleaning process, as shown in FIG. 8, first, a cleaning step (Step 10 (hereinafter, “Step” is described as “S”)) is performed. The cleaning step (S10) is a step in which the oil mist supplied to the air passage 60 by the cleaning fluid supply device 80 is ejected from the opening end of the air passage 60 in the cleaning process. Thereby, the air passage 60 formed in the mounting head 40 is cleaned with the oil mist.

Next, a blowing step (S30) is performed. The blowing step (S30) is a step of supplying positive pressure air to the air passage 60 in the cleaning process to remove oil remaining in the air passage 60. Thereby, the oil adhering to the inner wall of the air passage 60 or the like is jetted from the tip of the nozzle shaft 45 or the like in the washing step (S10) using the oil mist.

Subsequently, an idling step (S50) is performed. The idling step (S50) is a step in which the flow of the cleaning fluid in the air passage 60 is shut off during the cleaning processing, that is, the step of moving the nozzle shaft 45 up and down with the mechanical valve 65 being OFF. Thus, the sliding portions of the nozzle shaft 45 and the mechanical valve 65 are lubricated by the oil remaining in the air passage 60.

(3-2. Details of Cleaning Step) In the cleaning step (S10) in the cleaning processing, as shown in FIG. 9, first, the rotation of the R-axis motor 42 moves the rotary head 44 to the reference original position (S111). ). Next, the rotary head 44 is indexed at a predetermined angle (S112). The “predetermined angle” is represented by 360 / N when the number of nozzle shafts 45 held by the rotary head 44 is N.

Subsequently, the mechanical valve 65 provided for each nozzle shaft 45 (suction nozzle 46) is turned off by driving the stepping motor 66 (S113). Thereby, the in-shaft passage 61 is in a closed state. The control device 90 determines whether or not the calculation of the rotation angle of the rotary head 44 has been repeated N times (S114). If the number is less than N (S114: N), the above steps S111 to S114 are repeated.

By this processing, all the mechanical valves 65 corresponding to the respective nozzle shafts 45 are turned off. In other words, the in-shaft passage 61 of each nozzle shaft 45 is reset to a closed state. When it is determined that the rotation angle of the rotary head 44 has been calculated N times (S114: Y), the process proceeds to S121. Here, the cleaning switching valve 84 is switched to the right side (the cleaning oil passage 86 side) in FIG. 6, and the suction valve 89 is switched to the left side in FIG. 6 (S121).

Then, the positive pressure air supplied from the compressor 81 to the air supply passage 82 is sent to the cleaning oil passage 86 via the cleaning switching valve 84. When the positive pressure air flows through the cleaning oil passage 86, the mist-like fluorine oil generated by the lubricator 87 is supplied to the cleaning oil passage 86. As a result, the oil mist as the cleaning fluid is supplied to the supply pipe 88 of the mounting head cleaning device 70.

The oil mist supplied to the supply pipe 88 is introduced into the air passage 60 of the mounting head 40 via the connection pipe 64 of the mounting head 40. The positive pressure air supplied to the air supply passage 82 is supplied to the suction blower 73 via the suction valve 89 by switching the suction valve 89. As a result, the suction blower 73 is activated.

Subsequently, the mechanical valve 65 corresponding to the first nozzle shaft 45 indexed to the elevating position is raised by the stepping motor 66 and turned on (S122). Thereby, the first axial passage 61 of the nozzle shaft 45 is opened. Then, the oil mist introduced into the introduction passage 63 of the mounting head 40 is supplied to the shaft passage 61 of the nozzle shaft 45 via the head passage 62. The oil mist is ejected from the tip of the nozzle shaft 45 corresponding to the open end of the air passage 60 to the outside.

In this state, the control device 90 controls the mounting head 40 so that the nozzle shaft 45 is moved up and down and the nozzle shaft 45 is rotated around the axis (around the θ axis) in synchronization with the elevating operation of the nozzle shaft 45. The operation of the lifting mechanism and the rotating mechanism is controlled (S123). Specifically, the nozzle shaft 45 is first raised and lowered a plurality of times by driving a Z-axis motor 56 constituting a lifting mechanism. At this time, the nozzle shaft 45 is rotated by a preset angle each time the nozzle shaft 45 moves up and down by driving the θ-axis motor 51 constituting the rotation mechanism.

The rotation angle of the nozzle shaft 45 is set so that the index angle at the start of the lowering of the nozzle shaft 45 is different between the successive raising and lowering operations of the nozzle shaft 45. For example, when the rotation angle is set to 370 degrees, the control device 90 rotates the nozzle shaft 45 by 185 degrees in the same direction when the nozzle shaft 45 descends and rises. As a result, the index angle at the start of the descent of the next elevating operation of the nozzle shaft 45 differs by 10 degrees.

Thus, the nozzle shaft raising / lowering step in which the lifting / lowering mechanism operates so that the nozzle shaft 45 is raised / lowered, and the rotation mechanism operates so that the nozzle shaft 45 is rotated around the axis in synchronization with the lifting / lowering operation of the nozzle shaft 45. Is performed (S123). As a result, dust and the like that have entered the sliding portion of the air passage 60 and the nozzle shaft 45 (the fitting portion with the rotary head 44) are removed by the oil mist. In addition, as the nozzle shaft 45 rotates, the annular groove formed on the outer peripheral side of the nozzle shaft 45 is washed over the entire circumference. The oil mist ejected from the tip of the nozzle shaft 45 is sucked by the suction blower 73.

Subsequently, the mechanical valve 65 corresponding to the nozzle shaft 45 having cleaned the shaft passage 61 is turned off again (S124). Thereby, the in-shaft passage 61 is closed. Then, the rotary head 44 is indexed at a predetermined angle (S125). The control device 90 determines whether or not indexing of the rotation angle of the rotary head 44 has been repeated N times (S126). If the number is less than N (S126: N), the above steps S122 to S126 are repeated.

By this process, the air passages 60 are sequentially formed by the axial passages 61 of the first to Nth nozzle shafts 45, and the respective axial passages 61 are sequentially washed. When the rotation angle of the rotary head 44 is determined N times (S126: Y), the air passage 60 formed by the in-shaft passage 61 of the N-th nozzle shaft 45 is in a cleaned state. . Thereafter, the cleaning switching valve 84 and the suction valve 89 are respectively switched to the original positions (see FIG. 6) (S127). Thus, the supply of the oil mist to the mounting head 40 and the supply of the positive pressure air to the suction blower 73 are stopped.

(3-3. Details of Blowing Step) In the blowing step (S30) in the cleaning process, as shown in FIG. 10, first, the cleaning switching valve 84 is switched to the left side (the cleaning air passage 85 side) in FIG. The suction valve 89 is switched to the left side in FIG. 6 (S311). Then, the positive pressure air supplied from the compressor 81 to the air supply passage 82 is sent into the cleaning air passage 85 via the cleaning switching valve 84. The positive pressure air supplied to the air supply passage 82 is supplied to the suction blower 73 via the suction valve 89. As a result, the suction blower 73 is activated.

Next, the mechanical valve 65 corresponding to the first nozzle shaft 45 indexed to the elevating position is turned on (S312). Thereby, the first axial passage 61 of the nozzle shaft 45 is released. Then, the positive pressure air introduced into the introduction passage 63 of the mounting head 40 is supplied to the in-shaft passage 61 of the nozzle shaft 45 via the in-head passage 62. The positive pressure air blows out from the tip of the nozzle shaft 45 corresponding to the open end of the air passage 60 to the outside.

In this state, the control device 90 raises and lowers the nozzle shaft 45 a plurality of times, and rotates the nozzle shaft 45 around the axis (around the θ axis) in synchronization with the raising and lowering operation of the nozzle shaft 45 (S313). Synchronous control of the raising / lowering operation and rotation operation of the nozzle shaft 45 by the control device 90 is substantially the same as the synchronous control in S123 of the cleaning step (S10), and thus detailed description is omitted.

By the operation of the nozzle shaft 45, oil remaining on the air passage 60, the sliding portion of the nozzle shaft 45, and the sliding portion of the mechanical valve 65 is blown off and removed. Further, as the nozzle shaft 45 rotates, oil remaining in the annular groove formed on the outer peripheral side of the nozzle shaft 45 is also removed over the entire circumference. The oil thus removed is ejected from the tip of the nozzle shaft 45 together with the positive pressure air, and is sucked by the suction blower 73.

Subsequently, the mechanical valve 65 corresponding to the nozzle shaft 45 from which the oil in the shaft passage 61 has been removed is turned off again (S314). Thereby, the in-shaft passage 61 is closed. Then, the rotary head 44 is indexed at a predetermined angle (S315). The control device 90 determines whether or not indexing of the rotation angle of the rotary head 44 has been repeated N times (S316). If the number is less than N (S316: N), the above steps S312 to S316 are repeated.

By this process, the air passages 60 are sequentially formed by the axial passages 61 of the first to Nth nozzle shafts 45, and the oil remaining in each axial passage 61 is sequentially removed. When the rotation angle of the rotary head 44 is determined N times (S316: Y), the air passage 60 formed by the in-shaft passage 61 of the N-th nozzle shaft 45 removes residual oil. It is in the state that was done. Thereafter, the cleaning switching valve 84 and the suction valve 89 are respectively switched to the original positions (see FIG. 6) (S317). Thus, the supply of the positive pressure air to the mounting head 40 and the suction blower 73 is stopped.

(3-4. Details of Idling Step) In the idling step (S50) in the cleaning process, the flow of the cleaning fluid in the air passage 60 is shut off, that is, the cleaning switching valve 84 is in the original position (see FIG. 6), and the cleaning process is correct. The process is executed in a state where neither the compressed air nor the oil mist is supplied to the mounting head 40.

In the above state, as shown in FIG. 11, the control device 90 raises and lowers the nozzle shaft 45, and rotates the nozzle shaft 45 around the axis (around the θ axis) in synchronization with the raising and lowering operation of the nozzle shaft 45. (S511). At this time, the control device 90 controls the operation of the lifting mechanism and the rotation mechanism of the mounting head 40 such that the rotation angle of the nozzle shaft 45 in one lifting operation of the nozzle shaft 45 becomes 360 degrees or more.

Next, the mechanical valve 65 corresponding to the first nozzle shaft 45 indexed to the elevating position is moved up and down (S512). Thereby, the mechanical valve 65 is returned to the OFF state again after being switched to the ON state. Thus, when the nozzle shaft 45 and the mechanical valve 65 operate (S511, S512), the respective sliding parts are lubricated by the oil contained in the cleaning fluid.

Subsequently, the rotary head 44 is indexed at a predetermined angle (S513). The control device 90 determines whether or not indexing of the rotation angle of the rotary head 44 has been repeated N times (S514). If the number is less than N (S514: N), the above steps S511 to S513 are repeated. By this processing, the first to Nth nozzle shafts 45 and the mechanical valve 65 are sequentially operated in an idling manner, and each sliding portion is lubricated.

When the rotation angle of the rotary head 44 is calculated N times (S514: Y), the N-th nozzle shaft 45 and the mechanical valve 65 corresponding to the nozzle shaft 45 are in a state where the idling operation has been completed. is there. After that, the control device 90 ends the idling step (S50) and ends the cleaning process (see FIG. 8).

In the above embodiment, the control device 90 is configured to raise and lower the nozzle shaft 45 and the mechanical valve 65 once each. On the other hand, the control device 90 may move the nozzle shaft 45 and the mechanical valve 65 up and down a plurality of times. In the idling step (S50), the flow of the cleaning fluid is shut off. Therefore, the control device 90 may simultaneously execute the synchronous control of the elevating operation and the rotating operation of the nozzle shaft 45 (S511) and the control of the elevating operation of the mechanical valve 65 (S512).

(4. Effects of the Configuration of the Embodiment) In the mounting head cleaning apparatus 70 and the mounting head cleaning method according to the present embodiment, the component is sucked by the negative pressure air supplied through the air passage 60 by the negative pressure air supply device. The mounting head 40 includes a suction nozzle 46 and a nozzle shaft 45 that detachably holds the suction nozzle 46 and that can be moved up and down by a lifting mechanism and rotatable by a rotation mechanism. The mounting head cleaning device 70 cleans the air passage 60 formed inside the mounting head 40. In the mounting head cleaning device 70, a cleaning fluid supply device 80 that supplies a cleaning fluid composed of positive pressure air or oil mist to the air passage 60, and a nozzle shaft 45 is moved up and down in a cleaning process using the cleaning fluid supply device 80. And a control device 90 for controlling the operation of the elevating mechanism and the operation of the rotating mechanism so that the nozzle shaft 45 is rotated around the axis in synchronization with the elevating operation of the nozzle shaft 45. Further, in the mounting head cleaning method, in a cleaning process using a cleaning fluid supply device 80 that supplies a cleaning fluid composed of positive pressure air or oil mist to the air passage 60, an elevating mechanism operates so that the nozzle shaft 45 is raised and lowered. Nozzle shaft raising and lowering step (S123), and a nozzle shaft rotating step (S123) in which the rotating mechanism operates so that the nozzle shaft 45 is rotated around the axis in synchronization with the raising and lowering operation of the nozzle shaft 45 in the nozzle shaft raising and lowering step. And.

According to such a configuration, the air passage 60 formed in the mounting head 40 is entirely washed. In the present embodiment, the annular groove formed on the outer peripheral side of the nozzle shaft 45 is cleaned over the entire circumference, and the portion to be cleaned in the air passage 60 is prevented from being biased. Therefore, the cleaning efficiency is improved, and the time required for the cleaning process is reduced.

In the present embodiment, in the cleaning step (S10) in which the cleaning fluid supplied to the air passage 60 by the cleaning fluid supply device 80 is jetted from the open end of the air passage 60 during the cleaning process, the control device 90 controls the nozzle shaft. The nozzle shaft 45 is rotated around the axis in synchronization with the raising / lowering operation of the nozzle 45 (S123).

Here, the nozzle shaft 45 is held rotatably and rotatably with respect to the main body of the mounting head 40. Therefore, the air passage 60 that communicates the main body of the mounting head 40 with the nozzle shaft 45 expands and contracts as the nozzle shaft 45 moves up and down and rotates. In such a configuration, in the cleaning step (S10), the nozzle fluid 45 is rotated around the axis while moving up and down (S123), so that the cleaning fluid (oil mist) flows evenly through the air path 60 that expands and contracts. As a result, dust and the like sucked into the air passage 60 are reliably removed. Therefore, the cleaning efficiency is improved, and the time required for the cleaning process is reduced.

In the present embodiment, the cleaning fluid is an oil mist. In the air blowing step (S30) of supplying positive pressure air to the air passage 60 and removing the oil remaining in the air passage 60 in the cleaning process, the control device 90 controls the nozzle shaft 45 in synchronization with the vertical movement of the nozzle shaft 45. 45 is rotated around the axis (S313).

According to such a configuration, the oil remaining in the sliding portion of the nozzle shaft 45 and the air passage 60 is blown off and removed. Further, as the nozzle shaft 45 rotates, oil remaining in the annular groove formed on the outer peripheral side of the nozzle shaft 45 is also removed over the entire circumference. Further, a part of the positive pressure air enters the sliding portion of the nozzle shaft 45. Thereby, a part of the oil remaining in the air passage 60 is sent to the sliding portion of the nozzle shaft 45 with the flow of the positive pressure air. Thereby, oil is supplied to the sliding portion, and the lubricating property of the sliding portion is improved.

In the present embodiment, the cleaning fluid is an oil mist. In the idling step (S50) of raising and lowering the nozzle shaft 45 in a state where the flow of the cleaning fluid in the air passage 60 is interrupted in the cleaning process, the controller 90 sets the axis of the nozzle shaft 45 in synchronization with the vertical movement of the nozzle shaft 45. It is rotated around (S511).

According to such a configuration, the sliding portion of the nozzle shaft 45 is lubricated by the oil contained in the oil mist. Therefore, the lubricity of the nozzle shaft 45 is improved.

In the present embodiment, when the nozzle shaft 45 is moved up and down a plurality of times, the nozzle shaft 45 in one elevating operation is changed so that the index angle at the start of lowering of the nozzle shaft 45 differs between successive elevating operations. Is set. The control device 90 controls the operation of the elevating mechanism and the operation of the rotating mechanism based on the set rotation angle of the nozzle shaft 45 (S123, S313).

According to such a configuration, the index angle of the nozzle shaft 45 changes with respect to the position of the nozzle shaft 45 in the Z direction. Accordingly, the shape of the air passage 60 changes, so that the portion to be cleaned in the air passage 60 is prevented from being partially biased. Therefore, the cleaning fluid flows evenly in the air passage 60, the cleaning efficiency is improved in the cleaning step (S10), and the remaining oil is suitably removed in the air blowing step (S30).

In the present embodiment, when the control device 90 rotates the nozzle shaft 45 around the axis in synchronization with the elevating operation of the nozzle shaft 45, the rotation angle of the nozzle shaft 45 in one elevating operation becomes 360 degrees or more. Thus, the operation of the elevating mechanism and the operation of the rotating mechanism are controlled (S123, S313, S511).

According to such a configuration, the nozzle shaft 45 rotates over at least one round by at least one elevating operation. Thereby, the shape of the air passage 60 communicating between the rotary head 44 and the nozzle shaft 45 is suitably changed, and the cleaning efficiency is improved in the cleaning step (S10). In the blowing step (S30), the remaining oil is suitably removed. In the idling step (S50), the sliding portion of the nozzle shaft 45 is suitably lubricated.

<Modification of Embodiment> (Regarding Cleaning Fluid) In the embodiment, the cleaning process using the oil mist as the cleaning fluid has been exemplified. On the other hand, in the cleaning process, positive pressure air containing no oil may be used as the cleaning fluid. Specifically, in S121 (see FIG. 9) of the cleaning step (S10), the cleaning switching valve 84 is switched to the left side (the cleaning air passage 85 side) in FIG. This allows

Positive pressure air supplied from the compressor 81 to the air supply passage 82 is sent into the cleaning air passage 85 via the cleaning switching valve 84. Thereby, positive pressure air as a cleaning fluid is supplied to the supply pipe 88 of the mounting head cleaning device 70. In the cleaning process using positive pressure air as the cleaning fluid, the air blowing step (S30) for removing residual oil and the idling step (S50) for promoting lubrication with oil are not required.

(Regarding Synchronous Control of Up / Down Operation and Rotation Operation of Nozzle Shaft) In the embodiment, the nozzle shaft 45 has been exemplified as being controlled in synchronization with the up / down operation and rotation operation in the following cases. That is, during the cleaning (S123) in the cleaning step (S10), when removing the oil (S313) in the air blowing step (S30), and during lubrication (S511) in the idling step (S50), the rotation operation is synchronized with the lifting / lowering operation. Controlled.

On the other hand, the synchronous control of the nozzle shaft 45 may be executed by appropriately combining any of the above-mentioned timings. Alternatively, the synchronous control of the nozzle shaft 45 may be performed in a state where the air passage 60 is being reduced or increased in pressure. Specifically, there are the following aspects.

That is, a dummy nozzle that closes the air passage 60 is mounted on the nozzle shaft 45 instead of the suction nozzle 46. The dummy nozzle has, for example, an appearance similar to that of the suction nozzle 46, and differs from the suction nozzle 46 in that the dummy nozzle does not have an opening at the tip. Accordingly, when the dummy nozzle is mounted on the nozzle shaft 45, the air passage 60 is closed at the end on the mounting head 40 side.

Then, the control device 90 supplies negative pressure air to the closed air passage 60 to reduce the pressure in the air passage 60 or supplies positive pressure air to increase the pressure in the air passage 60. The control device 90 raises and lowers the nozzle shaft 45 when the pressure of the air passage 60 is reduced or increased, and rotates the nozzle shaft 45 around the axis (around the θ axis) in synchronization with the raising and lowering operation. The control device 90 sequentially executes this for the first to N-th nozzle shafts 45 as in the cleaning step (S10).

According to such synchronous control of the nozzle shaft 45, when the pressure in the air passage 60 is reduced, outside air flows in through the sliding portion of the nozzle shaft 45 and the sliding portion of the mechanical valve 65. When the pressure in the air passage 60 is increased, the positive pressure air flows out through the sliding portion of the nozzle shaft 45 and the sliding portion of the mechanical valve 65. As a result, dust and the like that have entered the sliding portion are efficiently removed. Further, since the oil is efficiently fed into the sliding portion, the sliding portion is suitably lubricated.

(Regarding the operation of the mechanical valve in the cleaning process) In the embodiment, the mechanical valve 65 controls before and after the cleaning (S122, S124) in the cleaning step (S10) and before and after the oil removal in the blowing step (S30) (S312, S314). ), And is switched to an ON state or an OFF state. On the other hand, the control device 90 may switch the mechanical valve 65 a plurality of times when the cleaning fluid is supplied to the air passage 60 in the cleaning process.

For example, at the time of cleaning (S123) in the cleaning process (S10), the mechanical valve 65 is turned off for a short period of time so as to cut off the supply of the cleaning fluid, and is then turned on again. Thereby, the control device 90 raises and lowers the pressure acting on the air passage 60. Then, the flow rate of the cleaning fluid in the air passage 60 changes, and dust and the like accumulated in the air passage 60 are efficiently removed.

1: Component mounting machine 10: Board transfer device, 20: Component supply device, 30: Component transfer device 40: Mounting head, 45: Nozzle shaft, 46: Suction nozzle 47: Driven gear, 48: θ-axis gear, 51: θ-axis motor 52: drive gear 53: nozzle gear 54: nozzle operating member 55: guide bar 56: Z-axis motor 57: ball screw mechanism 58: nozzle lever 60: air passage 65: mechanical switching valve (mechanical valve) 70: Mounting head cleaning device 80: Cleaning fluid supply device 90: Control device

Claims (9)

A suction nozzle for sucking a component by negative pressure air supplied from the negative pressure air supply device through an air passage;
The suction nozzle is detachably held, a nozzle shaft held rotatably by a lift mechanism and rotatable by a rotation mechanism, and is intended for a mounting head including:
A mounting head cleaning device for cleaning the air passage formed inside the mounting head,
The mounting head cleaning device,
A clamp mechanism to which the mounting head removed from the component mounter is fixed,
A cleaning fluid supply device for supplying a cleaning fluid comprising positive pressure air or oil mist to the air passage;
In the cleaning process using the cleaning fluid supply device, the nozzle shaft is moved up and down, and the operation of the elevating mechanism is performed so that the nozzle shaft is rotated around the axis in synchronization with the elevating operation of the nozzle shaft. A control device for controlling the operation of the rotation mechanism,
Equipped with a,
The cleaning fluid is the oil mist,
The cleaning process includes an idling step of raising and lowering the nozzle shaft in a state where the flow of the cleaning fluid in the air passage is blocked,
Said control device, wherein in the idling step synchronization with mounting head cleaning device you want to rotate. The nozzle shaft about the axis in the vertical movement of the nozzle axis. A dummy nozzle closing the open end of the air passage is mounted on the nozzle shaft in place of the suction nozzle,
Wherein the control device, wherein by supplying the negative pressure air to the air passage when said air passage is depressurized, or the air passage supplying the positive pressure air in the air passage is pressure increase 2. The mounting head cleaning device according to claim 1, wherein the nozzle shaft is rotated around an axis in synchronization with the elevating operation of the nozzle shaft. A suction nozzle for sucking a component by negative pressure air supplied from the negative pressure air supply device through an air passage;
The suction nozzle is detachably held, a nozzle shaft held rotatably by a lifting mechanism and rotatable by an elevating mechanism, and a mounting head comprising:
A mounting head cleaning device for cleaning the air passage formed inside the mounting head,
The mounting head cleaning device,
A clamp mechanism to which the mounting head removed from the component mounter is fixed,
A cleaning fluid supply device for supplying a cleaning fluid comprising positive pressure air or oil mist to the air passage;
In the cleaning process using the cleaning fluid supply device, the nozzle shaft is moved up and down, and the operation of the elevating mechanism is performed so that the nozzle shaft is rotated around the axis in synchronization with the elevating operation of the nozzle shaft. A control device for controlling the operation of the rotation mechanism,
Equipped with a,
A dummy nozzle closing the open end of the air passage is mounted on the nozzle shaft in place of the suction nozzle,
The control device supplies the negative pressure air to the air passage to reduce the pressure of the air passage, or supplies the positive pressure air to the air passage to increase the pressure of the air passage. when the synchronization with mounting head cleaning device you want to rotate. the nozzle shaft about the axis in the vertical movement of the nozzle axis. The cleaning fluid is the oil mist,
Before SL in the cleaning process, the idling step of lifting the nozzle axis while blocking the flow of the cleaning fluid in the air passage is included,
4. The mounting head cleaning apparatus according to claim 3, wherein the control device rotates the nozzle shaft around an axis in synchronization with an elevating operation of the nozzle shaft in the idling step . In the case where the nozzle shaft is moved up and down a plurality of times in the cleaning process, the index angle of the nozzle shaft at the start of descending is different between successive elevating operations so that the nozzle shaft is moved up and down in one elevating operation. The rotation angle is set,
The control device controls the operation of the elevating mechanism and the operation of the rotating mechanism based on the preset rotation angle of the nozzle shaft in the cleaning process of moving the nozzle shaft up and down a plurality of times . The mounting head cleaning device according to claim 1. The pre Symbol cleaning process, cleaning process the cleaning fluid by the cleaning fluid supply device is supplied to the air passage is ejected from the open end of the air passage is included,
The mounting head cleaning device according to any one of claims 1 to 5, wherein the control device rotates the nozzle shaft around an axis in synchronization with the elevating operation of the nozzle shaft in the cleaning process . The cleaning fluid is the oil mist,
The pre Symbol cleaning, blowing step for removing the oil remaining in the air passage by supplying positive pressure air to the air passage by the cleaning fluid supply device is included,
The mounting head cleaning device according to any one of claims 1 to 6, wherein the control device rotates the nozzle shaft around an axis in synchronization with an elevating operation of the nozzle shaft in the blowing process . The mounting head includes a valve that can switch supply and cutoff of the negative pressure air to the nozzle shaft,
The control device, when the cleaning fluid is supplied to the air passage in the cleaning process, switches the valve a plurality of times to increase or decrease the pressure acting on the air passage. The mounting head cleaning device according to any one of claims 1 to 7 . The control device is configured such that , when the nozzle shaft is rotated around the axis in synchronization with the elevating operation of the nozzle shaft in the cleaning process, the rotation angle of the nozzle shaft in one elevating operation is 360 degrees or more. The mounting head cleaning device according to any one of claims 1 to 8 , wherein the operation of the lifting mechanism and the operation of the rotating mechanism are controlled.