JP2547554B2 - How to automatically mount electronic components - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an electronic component for positioning and mounting a chipped electronic component such as a resistor, a capacitor or a transistor (hereinafter referred to as a chip component) on a printed circuit board. It relates to the automatic mounting method of.

[Prior Art] Generally, an electronic component automatic mounting device, for example, a chip component stored in a component supply unit such as a tape or a magazine is automatically taken out and placed at a predetermined position on a printed circuit board to which an adhesive is applied in advance. When positioning and mounting the printed circuit board, the printed circuit board is usually mounted on an XY table, and the XY table is moved and adjusted in the X-axis direction and the Y-axis direction. Is being positioned.

Conventionally, an automatic mounting device of this type, for example, Japanese Utility Model Application Laid-Open No. 57-48673 or Japanese Patent Application Laid-Open No. 61-161, which the present applicant has previously filed,
In the electronic component automatic mounting apparatus disclosed in Japanese Patent Publication No. 800, when the chip components are automatically placed and assembled at a predetermined position on the printed circuit board, the tape with the chip components attached at substantially equal intervals is wound. A component supply unit including a tape reel that has been stored once and a component delivery unit that delivers and delivers chip components on a tape supplied from this tape reel at a predetermined pitch is divided into, for example, different types or sizes of chip components. A plurality of component supply units can be mounted by arranging them in parallel on a movable table that is movable at appropriate intervals and moving the frame via a frame drive control means such as a drive ball screw. Positioning is controlled selectively to the pick-up position of the part pick-up means so that a chip part of a type or size according to the purpose can be taken out. The is proposed, there is what is subjected to practical use.

However, under the present circumstances, the gantry drive control means in such a conventional electronic component automatic mounting apparatus is controlled so that the acceleration during movement of the gantry is always constant regardless of the moving distance. .

[Problems to be Solved by the Invention] For this reason, in the conventional movement control means for the gantry, for example, a large number of component supply parts are arranged in a stack during one cycle of movement for assembling one chip component. So that the mounted base can be moved by a rotational movement of the ball screw by a moving distance that is twice the set distance of each component supply unit.
That is, as shown in FIG. 7, the ball screw is rotated at the number of revolutions N by accelerating from the movement start point a with a gradient of a predetermined acceleration.
The operation mode of the gantry that is decelerated by a gradient with a predetermined acceleration at time b after T time and becomes stopped at a stop point c after 2T time, which is the time for moving the gantry in the cycle time of the device. When set to,
It corresponds to the area enclosed by abc. At this time, if the movement control between the parts supply parts of the gantry by the program is required to move only one pitch during the movement of one cycle for assembling this one chip part. The operation mode of the gantry is point a → d →
Therefore, the movement distance for one pitch corresponds to the area surrounded by the point abe, and although the movement time of the gantry can be shortened by this, the same acceleration as for two pitches is applied, which causes wear of the drive system. Not only shortens the overall life of the device, but also increases vibration, which adversely affects the positioning action of the printed circuit board and chip parts during mounting.
There was such a problem.

The present invention has been made under the above circumstances, and an object of the present invention is to reduce wear of a drive system to prolong the entire life of the apparatus, and to reduce vibration to prevent printing during mounting. An object of the present invention is to provide an automatic mounting method for electronic components that does not adversely affect the positioning action of the substrate and chip components.

[Means for Solving Problems] Therefore, according to the present invention, the printed circuit board is placed on the XY table to control the position in advance, and the component supply means moves the component to a predetermined position on the printed circuit board. In an electronic component automatic mounting apparatus in which chip-shaped electronic components selectively supplied through a take-out unit are automatically placed and mounted, the component supply unit includes a plurality of components mounted on a movable mount. The pedestal has a structure in which the supply units are stacked and arranged at a predetermined interval, and chip-shaped electronic components selectively supplied from one of the respective component supply units are delivered to the component extracting means. Is controlled to move one of the component supply units through a gantry drive control unit in a direction in which it is selectively positioned at a predetermined position with respect to the component extraction unit, and next When the component supply unit is positioned with respect to the component take-out means within a predetermined movement time, when the movement distance is short, the gantry is controlled to move with a small movement acceleration as compared to when the movement distance is long. It was done.

[Operation] That is, according to the present invention, with the above configuration,
For example, during one cycle of assembly of one chip component, the gantry can be moved a movement distance of twice the set interval of each component supply unit, and the gantry can be moved. If the operation mode of the gantry is set so that the time matches the cycle time of the device, the acceleration applied to the gantry at the time of one pitch interval movement between each component supply unit can be set to several paragraphs. The wear of the drive system can be reduced, and since the vibration is small, it is possible to prevent the positioning action of the printed circuit board and the chip component during assembly from being adversely affected.

[Example] Hereinafter, the present invention will be described in detail with reference to an embodiment shown in FIGS. 1 to 6.

FIG. 1 schematically shows an electronic component automatic mounting apparatus according to the present invention, in which (1) is a component supply means.
The component supply means (1) includes a movable mount (2) and
On the pedestal (2), a pedestal drive control means including a drive motor (3) and a ball screw (4) for moving the pedestal (2) in the direction (A) shown by the solid line in FIG. 1 at equal pitches or counting pitches. , And a plurality of component supply units (5), which are stacked and arranged in parallel at a predetermined pitch along the moving direction of the chip component, the component supply unit (5) includes chip components (U) substantially equal to each other. A tape reel (7) in which tapes (6) attached at intervals are wound and housed, and this tape reel (7)
Part feeding unit (8) for feeding out chip parts (U) on the tape (6) supplied from
It consists of Then, the chip parts (U) on the tape (6) fed out from each of the part feeding units (8) of the part feeding means (1) are taken out one by one through the part taking-out means (9). The component take-out means (9) is a rotary table (10) which is intermittently rotated by a drive system (not shown).
And a plurality of suction nozzles (11) supported vertically by a cam drive device (not shown) in the circumferential direction of the lower surface of the rotary table (10). The parts supply section (5)
.. one of which is selectively controlled to be positioned at a predetermined position by movement control of a gantry (2) described later, and the tape (6) fed out from the component supply unit (5) positioned in this way The upper chip part (U) is suction-held by one of the suction nozzles (11) ... and taken out, and the rotary table (10) is rotated to be conveyed by rotation to once suck the suction nozzle. The chip component (U) sucked and held by (11) is placed on the positioning unit (12), and the chip component (U) is mounted on the positioning unit (12) by a plurality of claw members (13) from four sides. After determining the position and orientation of U), the chip component (U) is automatically placed and mounted on the printed circuit board (P) installed on the XY table (14). .

The XY table (14) includes an X-axis table (15) movable in the X-axis direction by a drive system (not shown) and a Y-axis table (16) movable in the Y-axis direction. The printed circuit board (P) installed on the X-axis table (15) is attached to the X-axis table (P) before mounting the chip component (U) in advance.
Positioning is performed by movably adjusting in the axial direction and the Y-axis direction.

Further, FIG. 2 is a block diagram showing a gantry drive control of the electronic component automatic mounting apparatus according to the present invention, in which (20) is an interface. The interface (20) rotates an acceleration / deceleration controller (21) and a driver (22) that control the movement of the drive motor (3) of the gantry (2) and a drive motor (23) of the rotary table (10). A driver (24) for controlling, a sensor (25) for detecting a fixed position of the rotary table (10), and a suction nozzle control section (26) for controlling suction of the suction nozzle (11),
While the personal computer (27) and the start switch (28) are connected, each of these control elements is a central information processing device (hereinafter abbreviated as CPU).
It is designed to be program controlled by (30). In the figure, (31) is an address counter, (32) is a data memory, and (33) is a current position data RAM. As shown in FIG. 3, the personal computer (27) is used.
Data memory (3
2), for example, in RAM, data indicating the position of the mount (2)
R _{1 to} R ₁₀₀ (34) are stored corresponding to each address, and control command E (3
5) is stored.

Further, FIG. 4 shows a part of a timing chart of an automatic mounting apparatus for electronic parts according to the present invention. When the cycle time of the apparatus is 4T [sec], first, the rotary table (10) is moved to 2T. Rotate for 1 index in [sec],
After that, the suction nozzle (11) descends and the chip component (U)
This means that one cycle is completed by adsorbing and holding and then rising again, where the time during which the gantry (2) can move is set to 2T [sec]. The pedestal (2) in the apparatus is capable of two pitches between the respective component supply units (5) within one cycle.

Next, the flow of such a movement control method of the gantry (2) will be described below based on the flowchart shown in FIG.

First, by turning on the start switch (28), the address counter (31) is cleared and initialized (ST-1). Next, the address counter (31) is stepped up (ST-2), the present position data of the gantry (2) in the parts supply section (5) and the gantry (2) indicated by the address counter (31).
The movement pitch and the movement direction are calculated with the data (34) indicating the position next to (ST-3).

Here, it is determined whether or not the movement pitch is "0" (ST-
4) If the movement pitch is "0", the operation proceeds to ST-10, while in ST-5, it is determined whether the movement pitch is "1". If the movement pitch is "1", Move to ST-10. Then, in ST-6, it is determined whether or not the moving pitch is "2", and if the moving pitch is "2", the process proceeds to ST-15.

If the movement pitch in ST-6 is "3" or more, the range in which the gantry (2) can move within 2 pitches while the rotary table (10) that is the component take-out means (9) makes one rotation If it is set to, it is necessary to stop the rotary table (10) or gain time to move by decelerating. In this embodiment, the rotary table (10) is stopped (ST -7).

Then, in ST-8, the acceleration / deceleration controller (21) is set to a high acceleration pattern (the operation mode of point abc shown in FIG. 6), and based on this operation mode, the gantry (2) is set to the specified pitch amount. Parts supply unit (5)
Is selectively positioned at a predetermined position with respect to the component take-out means (9) (ST-9).

In this state, the drive motor (23) of the rotary table (10) is driven, the suction nozzle (11) is lowered by a cam mechanism (not shown), and the suction nozzle control unit (26) is operated to supply the components. The chip component (U) on the tape (6) fed out from the component extrusion unit (8) of the section (5) is adsorbed (ST-10).

Then, the fixed position sensor (25) of the rotary table (10) determines whether or not the rotary table (10) has rotated once (ST-11), and the rotary table (10) is set to 1
Once rotated, the position data (34) of the gantry (2) indicated by the address counter (31) is set to the current position data (33) (ST-12), and the control command indicated by the address counter (31) is set. Whether there is "E" is confirmed and the end of processing is judged (ST-13). At this time, if it is not the end, shift to ST-2.

If it is determined in ST-13 that the processing is completed, the drive motor (23) of the rotary table (10) is stopped (ST-14). On the other hand, when the gantry (2) moves by 2 pitches, the acceleration / deceleration controller (21) is set to a high acceleration pattern (operation mode of point abc shown in FIG. 6), and the gantry (2) is started based on this operation mode. (ST-15), ST-10
Move to. When the gantry (2) moves one pitch, the acceleration / deceleration controller (21) is set to a low acceleration pattern (operation mode at point afc shown in FIG. 6), and the gantry (2) is set based on this operation mode. Start (ST-16) and move to ST-10.

In this way, when the gantry (2) moves 1 pitch or 2 pitches, it can move 2 pitches within one cycle of the rotary table (10),
The gantry (2) can be moved to ST-10 without waiting for the completion of the movement.

That is, according to the present invention, as shown in FIG. 6, even if the movement time of the gantry (2) is 2T [sec], the cycle time of the apparatus is not reduced, so that the points a → f → c. The pedestal (2) is moved in the operation mode, and the rotation speed [rps] of the ball screw (4) is the highest (1/2) ・ N so that the movement distance for one pitch corresponds to the area surrounded by the point afc. Variably controlled to the number of rotations of the gantry (2)
The acceleration at the time of movement becomes the gradient of the line connecting the points a → f, which makes it possible to make a few paragraphs from the conventional acceleration shown in FIG. 7.

By the way, a ball screw between the operation mode (points a → f → c) of the gantry (2) of the present invention shown in FIG. 6 and the operation mode (points a → d → e) of the gantry in the conventional apparatus shown in FIG. When the lifespan of the drive system is compared with a specific formula, the maximum rotation speed N ₁ during one pitch feed is as follows when the acceleration during movement of the gantry is constant, as in the conventional device shown in FIG. Travel time T ₁ is Becomes

On the other hand, as in the present invention shown in FIG. 6, the movement time of the gantry is 2T [se when the acceleration when the gantry is moved is variable.
c], the maximum rotation speed is (1/2) N [rp
s].

Here, the fatigue life S [rev] of the ball screw is expressed by the following formula: S = {Ca / (Fa · fw)} ³ × 10 ⁶ [rev] Ca: Basic dynamic load rating [kgf] Fa of the ball screw : Axial load [kgf] fw: Load coefficient Also, axial load Fa is Fa = mα = (W / g) ・ α [kgf] m: Mass of moving object [kg] α: Acceleration [mm / sec ² ] G: Gravity acceleration [mm / sec ² ] Furthermore, the acceleration α is α = N ・ L / T [mm / sec ² ] N: Ball screw rotation speed [rps] L: Ball screw lead pitch [mm] T: It is expressed in acceleration time [sec].

From the above equations, the acceleration α ₁ , axial load Fa ₁ , and ball screw fatigue life S ₁ in the conventional device are α ₁ = N · L / T [mm / sec ² ] Fa ₁ = (W / g) ・ ( NL / T) [kgf] S ₁ = {Ca / (Fa ₁ · fw)} ³ × 10 ⁶ [rev], and also the acceleration α ₂ , axial load Fa ₂ , and ball screw fatigue life S in the device of the present invention. ₂ is α ₂ = (1/2) N · (L / T) = N · L / 2T [mm / sec ² ] Fa ₂ = (W / g) · (N · L / 2T) [kgf] S ₂ = {Ca / (Fa ₂ · fw)} ³ × 10 ⁶ [rev], and comparing them, S ₂ / S ₁ = Fa ₁ ³ / Fa ₂ ³ = 8 (times). In this comparative formula, the load coefficient fw was calculated to be constant, but naturally, the value of the load coefficient fw decreases as the acceleration decreases, and as a result, the life of the device of the present invention is eight times or more that of the conventional device. You can see that it is extended.

Further, in the above-described embodiment, the case where the gantry can move two pitches in one cycle of the apparatus has been described, but the present invention is not limited to this, and the gantry can move one pitch or more. The present invention can also be applied to the case where there is a margin, which makes it possible to extend the life of the drive system composed of the ball screw by the amount of the margin.

In addition, it goes without saying that the present invention can be variously modified and implemented without departing from the gist of the present invention.

As described above, according to the present invention, the printed circuit board is placed on the XY table for positioning control in advance, and
In an electronic component automatic mounting device in which a chip-shaped electronic component selectively supplied from a component supply unit through a component extraction unit to a predetermined position on the printed circuit board is automatically placed and mounted, The component supply means stacks and arranges a plurality of component supply units on a movable pedestal at a predetermined interval, and a chip-shaped electronic component selectively supplied from one of these component supply units is used as the component. In the direction in which one of the respective component supply units is selectively positioned at a predetermined position with respect to the component unloading means via the gantry drive control means. When the next component supply unit is controlled to move and the next component supply unit is positioned with respect to the component removal means within a predetermined movement time, the movement distance is short when compared to when the component supply unit is long. Since the gantry is controlled so as to be moved by a small movement acceleration, for example, during one cycle of assembly of one chip component, the gantry is moved at the intervals set by the respective component supply units. If the operation mode of the gantry is set so that the gantry can be moved a double movement distance and the gantry movement time matches the cycle time of the device, one pitch between each component supply unit can be set. Acceleration applied to the gantry during interval movement can be reduced to several paragraphs, which reduces wear on the drive system and reduces vibrations, which helps in positioning the printed circuit board and chip parts during assembly. There is no adverse effect, and during normal equipment operation, most chip parts can be programmed to move in 1-pitch steps, greatly extending the overall life of the equipment. Succoth can.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic perspective view showing an embodiment of an automatic mounting apparatus for electronic parts according to the present invention, and FIG. 2 is a movement control system for a gantry on which a parts supply section is similarly arranged. Is a block diagram of FIG. 3, FIG. 3 is an explanatory view of a data memory, FIG. 4 is an explanatory view showing a part of a timing chart of the same, FIG. 5 is a flowchart of a movement control system of a gantry, and FIG. FIG. 7 is an explanatory view showing the operation mode characteristics, and FIG. 7 is an explanatory view showing the operation mode characteristics of the mount in the conventional electronic component automatic mounting apparatus. (1) ... Parts supply means, (2) ... Stand, (3) ... Drive motor, (4) ... Ball screw, (5) ... Parts supply section, (6) ... Tape, (7) …… Tape reel, (8) …… Parts sending unit, (9) …… Parts removing means, (10) …… Rotary table, (11) …… Suction nozzle, (12) …… Positioning unit, (14) ... XY table, (15) ... X-axis table, (16) ... Y-axis table, (U) ... chip parts, (P) ... printed circuit board.

Front page continuation (72) Inventor Yoshio Ueoka 2-18 Keihan Hondori, Moriguchi Sanyo Electric Co., Ltd. (56) Reference JP-A-52-92372 (JP, A) JP-A-57-160377 (JP, A) JP-A-57-160378 (JP, A)

Claims (1)

(57) [Claims] 1. A chip in which a printed circuit board is placed on an XY table and the positioning of the printed circuit board is controlled in advance. The chip is selectively supplied from a component supply means to a predetermined position on the printed circuit board through a component extraction means. In an electronic component automatic mounting apparatus in which electronic components are automatically placed and mounted, the component supply means stacks and arranges a plurality of component supply units on a movable mount at predetermined intervals, A structure in which a chip-shaped electronic component selectively supplied from one of these component supply units is sent to the component extracting means,
The mount is controlled to move one of the component supply units through a mount drive control unit in a direction in which it is selectively positioned at a predetermined position with respect to the component pick-up unit, and the component supply for which the component is picked up is supplied. When the next component supply unit is positioned with respect to the component take-out means within a predetermined movement time, when the movement distance is short, control is performed so as to move the gantry with a small movement acceleration compared to when the movement distance is long. A method for automatically mounting electronic components, which is characterized in that