JP2002176293A - Method and device for mounting electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic part mounting device of high productivity wherein an electronic part is placed on a substrate with no damage while pressed with an appropriate load. SOLUTION: A nozzle slider 32 is slidable together with a magnetic member 42 as one body in the axial direction under a magnetic force, while the nozzle slider 32 can be elastically energized in the direction of a magnetic-force neutral position. There are provided a first electromagnet 36 wherein the magnetic-force neutral position is in the range on the protrusion side beyond the most protruded position of the nozzle slider 32 toward a tip 32b side, and a first current supply means 14 wherein the electromagnet 36 is supplied with a retention current of absolute value 0 or higher so that the nozzle slider 32 is held at the protrusion position against a suction under a negative pressure. The first current supply means 14 selectively supplies the first electromagnet 36 with the retention current and a pressing current with an absolute value larger than that of the retention current.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electronic component mounting apparatus and an electronic component mounting method for mounting electronic components on a substrate.

[0002]

2. Description of the Related Art Conventionally, an electronic component mounting apparatus having an electronic component suction nozzle 100 capable of vacuum-sucking electronic components as shown in FIG. 5 has been widely used for mounting electronic components on a substrate. . Electronic component mounting equipment is generally Z
, A head part supporting the slide shaft movably in the Z direction and rotatable around the θ axis, and an XY supporting the head part movably in the XY directions. And a drive unit.

An electronic component suction nozzle 100 is detachably supported near a lower end of a slide shaft, and is capable of vacuum suction of an electronic component at its front end by a negative pressure supplied through the slide shaft. It is movable between the device and the substrate.

[0004] The electronic component suction nozzle 100 is a cylindrical body, and the distal end portion 102 is formed by a negative pressure supplied from the base end portion 102a side.
b, a nozzle slider 102 capable of vacuum-sucking an electronic component;
a nozzle holder 104 slidably supported in a range between a retracted position at which the nozzle slider 1 is most retracted to the side a;
02 in the direction of the tip 102b.

The nozzle slider 102 includes an electronic component 108
When vacuum suction in the electronic component supply device, or
When the electronic component 108 is placed on the substrate, the electronic component 108 is sandwiched between the electronic component supply device or the substrate and the distal end portion 102b, and at this time, the electronic component 108 is retracted toward the base end portion 102a to avoid damage to the electronic component. It has been like that.

The nozzle slider 102 is normally urged in the direction of the tip 102b by the buffer spring 106 and is held at the lowermost protruding position. This projecting position is a normal position for controlling the mounting of electronic components.

If the urging force of the buffer spring 106 is too strong, there is a risk of damaging the electronic components. If the urging force is too weak, the nozzle slider 102 is sucked together with the electronic components toward the base end portion 102a during vacuum suction of the electronic components. There is a possibility that the control position of the slider 102 does not match the actual position and the electronic component is erroneously mounted on the substrate. Therefore, a buffer spring 106 having an appropriate urging force is mounted on the electronic component suction nozzle 100.

In recent years, there has been an increasing number of electronic components that need to be further pressed and stuck to and stabilized on the substrate, such as flip chips with stud bumps, after being mounted on the substrate.

For example, the flip chip 1 shown in FIG.
In the case of 08, the stud bump 108a on the lower surface side of the flip chip 108 is placed on the substrate 110 so as to match the pad 110a on the substrate 110, and then further pressurized to plastically deform the stud bump 108a, and the pad 110a
It is necessary to adhere and stabilize on top.

[0010]

However, the cushioning spring 10
Numeral 6 applies the nozzle slider 102 with a small urging force in the direction of the distal end portion 102b in order to absorb an impact when the electronic component is mounted on the substrate, reduce the impact force, and prevent the electronic component from being damaged. The biasing force is generally smaller than the pressing force required to bring the stud bumps into close contact with the pads on the substrate.

Therefore, the tip 1 of the nozzle slider 102
02b is pressed against the flip chip 108 so that the flip chip 108 is located between the nozzle slider 102 and the substrate 110.
However, there is a problem that a sufficient pressing force cannot be obtained even when the stud bump 108a is interposed between the pad 110a and the pad 110a on the substrate 110.

On the other hand, the buffer spring 106 is set so that the buffer spring 106 urges the nozzle slider 102 with a large urging force in the direction of the tip end portion 102b. If the speed of lowering the substrate on the substrate is reduced, a sufficient pressing force for bringing the stud bumps into close contact with the pads on the substrate can be obtained, and the impact force when the flip chip contacts the substrate can be reduced. Can be prevented from being damaged.

However, reducing the lowering speed of the electronic component suction nozzle causes a new problem of lowering the production efficiency.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is an electronic component with high production efficiency that can be mounted on a substrate without damaging the electronic component and pressurized with an appropriate load. An object is to provide a mounting device.

[0015]

According to the present invention, there is provided a nozzle slider in which an electronic component can be vacuum-sucked at a distal end portion by a negative pressure supplied from a base end portion in a cylindrical body. An electronic component comprising: a nozzle holder that slidably supports the nozzle slider in a range between a protruding position that protrudes most toward the distal end side in the axial direction and a retracted position that is most retracted toward the base end side. In an electronic component mounting apparatus that has a suction nozzle and mounts an electronic component on a substrate, the nozzle slider is configured to be slidable in an axial direction by a magnetic force, and the nozzle slider is elastically moved in a direction of a magnetic neutral position. The neutral position of the magnetic force can be set in the neutral position by supplying the holding position having an absolute value of 0 or more to the electromagnet and the electromagnet positioned on the protruding side with respect to the protruding position. Current supply means capable of holding the nozzle slider at the protruding position against the attraction force, and the current supply means has a pressurizing current having an absolute value larger than the absolute value of the holding current. The above object is achieved by an electronic component mounting apparatus characterized in that the holding current can be selectively supplied to the electromagnet.

The current supply means may vary the supply current value of the pressurizing current, and the urging force of the nozzle slider caused by the pressurizing current may be reduced by a pressing force for stabilizing the electronic component on the substrate. A first control unit for controlling the current supply unit according to the type of electronic component to be mounted may be provided so as to be equal.

Further, at the start of the supply of the pressurizing current by the current supply means, the current supply means may be arranged such that the absolute value of the supply current of the current supply means continuously increases to become the absolute value of the pressurization current. May be provided.

Further, the electromagnet is provided as a first electromagnet, the current supply means is provided as a first current supply means, and the nozzle slider can be biased in a direction of a second magnetic neutral position. A second electromagnet whose magnetic neutral position is in a range closer to the retracted side than the protruding position, a combined force of an urging force of the second electromagnet and a suction force of the negative pressure, the nozzle slider, and the nozzle slider A buffer current that balances the gravity acting on the electronic component vacuum-adsorbed to the second electromagnet is supplied to and interrupted by the second electromagnet.
May be provided.

Further, according to the present invention, an electronic component is vacuum-adsorbed at the tip of the nozzle slider in the electronic component mounting apparatus,
The electronic component is lowered from above the substrate to a predetermined mounting position on the substrate, and when the electronic component approaches the substrate, the supply of the buffer current from the second current supply means to the second electromagnet is started. In addition, the above object is achieved by an electronic component mounting method characterized by mounting and releasing the electronic component on a substrate while supplying the buffer current.

According to the present invention, an electronic component can be placed on a substrate without being damaged, and can be pressed with an appropriate load.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electronic component mounting apparatus 10 according to an embodiment of the present invention is characterized by the structure of an electronic component suction nozzle 12 shown in FIGS. It comprises first and second current supply means 14 and 16 for supplying a current to the nozzle 12, and first and second control means 18 and 19 for controlling the first current supply means 14. And

An outline of the overall structure of the electronic component mounting apparatus 10 is as follows. The electronic component mounting apparatus 10 includes a cylindrical slide shaft 20 in the Z direction and a
And a XY drive unit 24 for supporting the head unit 22 so as to be movable in the Z direction and rotatable around the θ axis, an XY drive unit 24 for supporting the head unit 22 movably in the XY direction, and the electronic component suction nozzle. 12 has an image recognition device 25 capable of detecting a suction error of an electronic component vacuum-sucked.

The electronic component suction nozzle 12 is detachably supported near the lower end of the slide shaft 20, and is capable of vacuum suction of the electronic component 26 by a negative pressure supplied through the slide shaft 20, and supplies the electronic component. It is movable between the device 28 and the substrate 30. In addition,
Reference numeral 26a in FIG. 1 denotes a stud bump (terminal) of the electronic component 26, and reference numeral 30a denotes a pad on the substrate 30 to be joined to the stud bump 26a.

The structure of the electronic component suction nozzle 12, the first and second current supply means 14 and 16, and the first and second control means 18 and 19 will be described below. The structure of the other parts of the electronic component mounting apparatus 10 is the same as that of the related art, and the description is omitted.

The electronic component suction nozzle 12 is a cylindrical body, and the distal end portion 32b is formed by a negative pressure supplied from the base end portion 32a side.
, A nozzle slider 32 capable of vacuum-sucking electronic components, a projecting position where the nozzle slider 32 projects most toward the distal end portion 32b in the axial direction, and the base end portion 32a.
A nozzle holder 34 slidably supported in a range between the retracted position closest to the side and the first and second electromagnets 3
6, 38.

The nozzle slider 32 has a structure in which an iron ring-shaped magnetic member 42 is fitted around the base end 32a of a pipe-shaped nozzle slider body 40. The nozzle body 40 is made of non-magnetic stainless steel. Have been.

That is, the nozzle slider 32 is configured to be slidable in the axial direction by magnetic force integrally with the magnetic member 42.

The nozzle boulder 34 is a substantially cylindrical body having four stepped holes which become thicker in the order of an upper hole 34a, a middle hole 34b, a lower hole 34c, and a lower female screw portion 34d. The slide shaft 2
0 It is detachable near the lower end.

The nozzle boulder 34 is provided with the middle hole 34.
3B, the nozzle slider 32 is loosely fitted to the outer peripheral portion of the magnetic member 42, and is loosely fitted to the nozzle slider body 40 in the center hole 34g of the substantially ring-shaped lower end cover 34f. It is slidably supported in the direction.

The lower end cover 34f fits into the lower hole 34c in the upper half outer peripheral portion, and is screwed to the lower end female screw portion 34d in the lower half male screw portion.

The first electromagnet 36 includes a coil formed in a substantially ring shape. The first electromagnet 36 is fitted into the lower step hole 34c of the nozzle holder 34 at an outer peripheral portion, and the nozzle slider body 40 is formed at a center hole 36a. And the nozzle slider 32 can be elastically biased in the direction of the first magnetic neutral position.

The first magnetic neutral position is a position where the axial center of the magnetic member 42 and the axial center of the first electromagnet 36 coincide. In the example of the present embodiment, the nozzle slider 32 does not slide to the first magnetic neutral position.

The first electromagnet 36 contacts the upper end stepped portion of the lower step hole 34c at the upper end, and contacts the upper end of the lower end cover 34f at the lower end, and is fixed in the nozzle holder 34.

At the lower end of the magnetic member 42, the sliding position at which the nozzle slider 32 contacts the upper end of the first electromagnet 36 is defined as the projecting position, and the projecting position is determined by the control of the nozzle slider 32. It is a normal position. The neutral position of the magnetic force is in a range on the protruding side from the protruding position.

The second electromagnet 38 includes a coil formed in a substantially ring shape similarly to the first electromagnet 36, and is fitted to the middle hole 34b of the nozzle holder 34 at the outer peripheral portion. At the upper end, the middle step hole 34b
, The nozzle holder 34 can be biased to a second magnetically neutral position.

The second magnetic neutral position is the position of the magnetic member 4
The center of the second electromagnet 38 in the axial direction coincides with the center of the second electromagnet 38 in the axial direction, which is a range closer to the retracted side than the projecting position. Note that, in the example of the present embodiment, the nozzle slider 32 does not slide to the second magnetic neutral position.

The nozzle slider 32 is positioned at the base end 32.
In FIG. 5A, the sliding position in contact with the lower end of the second electromagnet 38 is the retracted position.

The first current supply means 14 includes a current supply device capable of supplying an intermittent current by pulse width modulation (PWM), and is connected to the first electromagnet 36.
By supplying a holding current to the electromagnet 36, the nozzle slider 32 can be held at the protruding position against the suction force of the negative pressure, and the absolute value of the holding current is greater than the absolute value of the holding current. The current and the holding current can be selectively supplied to the first electromagnet 36.

The second current supply means 16 also includes a current supply device capable of supplying an intermittent current by pulse width modulation (PWM), and is connected to the second electromagnet 38. The buffer current that balances the combined force of the urging force of the nozzle slider 32 and the suction force due to the negative pressure with the gravity acting on the nozzle slider 32 and the electronic components vacuum-adsorbed to the nozzle slider 32 by the second
Can be supplied to and cut off from the electromagnet 38.

The first control means 18 is connected to the first current supply means 14, and the urging force of the nozzle slider 32 by the pressurizing current is equal to the pressing force for stabilizing the electronic component on the substrate. Thus, a signal is output to the first current supply means 14 in accordance with the type of electronic component to be mounted, and the first current supply means 14 is controlled.

The second control means 19 is also connected to the first current supply means 14, and the supply of the first current supply means 14 is started when the first current supply means 14 starts supplying the pressurizing current. A signal is output to the first current supply means 14 so as to control the first current supply means 14 so that the current absolute value continuously increases and becomes the pressurization current absolute value. I have.

Next, the operation of the electronic component mounting apparatus 10 will be described. The operation of the electronic component mounting apparatus 10 differs between the case where a light electronic component is mounted and the case where a heavy electronic component is mounted.

Here, the light electronic component means an electronic component in which the gravity acting on the electronic component and the nozzle slider 32 is smaller than the suction force due to the negative pressure, and the heavy electronic component means the electronic component and the nozzle. It means an electronic component in which the gravity acting on the slider 32 is equal to or more than the suction force due to the negative pressure. First, a case where a light electronic component is mounted on a substrate will be described.

The electronic component 2 on the electronic component supply device 28
6 is vacuum-adsorbed when the head unit 22 and the X-
After the Y drive unit 24 is driven to position the electronic component suction nozzle 12 above the electronic component 26, a negative pressure is supplied to the electronic component suction nozzle 12 via the slide shaft 20 while lowering.

At this time, as shown in FIG.
With the current supply means 14 supplying the holding current to the first electromagnet 36, the tip 32b of the nozzle slider 32 is brought into contact with the upper surface of the electronic component 26.

The nozzle slider 32 is retracted against the urging force of the first electromagnet 36 while the electronic component 26
Without damaging the electronic component 26, the electronic component 26 is vacuum-adsorbed.

Next, when the head part 22 is driven to raise the electronic component suction nozzle 12, the nozzle slider 32 is urged by the first electromagnet 36 and resists the suction force caused by the negative pressure. It slides to the projecting position and is held at the projecting position.

In this state, the electronic component 26 is moved above the image recognition device 25 to detect a suction error. Since the nozzle slider 32 is held at the protruding position, which is the regular position, the suction error can be accurately detected.

Next, the head section 22, the XY drive section 24
Is driven to position the electronic component 26 above the substrate 30 while correcting the suction error, and then lower the electronic component 26. By the correction of the suction error, the electronic component 26 comes into contact with the substrate 30 in a state where its own stud bump 26a and the pad 30a of the substrate 30 are surely coincident with each other.

When the electronic component 26 comes into contact with the substrate 30, the nozzle slider 32 moves to the first electromagnet 36.
The electronic component 26 absorbs an impact when the electronic component 26 comes into contact with the substrate 30 and keeps the impact force low, so that the electronic component 26 is not damaged.

In this state, while the supply of the negative pressure is stopped,
When a slight positive pressure is supplied to the electronic component suction nozzle 12 through the slide shaft 20, the electronic component 26
Is released from the vacuum suction of the nozzle slider 32.

Next, after the supply of the holding current by the first current supply means 14 is stopped, the supply of the pressurizing current is started.

At this time, the first control means 18 controls the first control unit 18 so that the urging force of the nozzle slider 32 by the pressurizing current becomes equal to the pressing force for stabilizing the electronic component 26 on the substrate 30. The second control means 19 controls the current supply means 14 so that the absolute value of the supply current of the first current supply means 14 increases continuously to become the absolute value of the pressurizing current. , And controls the first current supply means 14.

Thus, the electronic component 26 is connected to the substrate 3
The bumps 26a are pressed onto the pads 30a and adhere to the pads 30a while being slightly plastically deformed, and are stabilized on the substrate 30.

At the start of the pressurizing current supply, the second control means 19 controls the first current supply means 14 so that the supply current value of the first current supply means 14 continuously increases. Since the control is performed, the pressure at which the nozzle slider 32 presses the electronic component 26 gradually increases, and the pressure can be applied to the substrate 30 without damaging the electronic component 26.

Further, the first current supply means 14 is controlled in accordance with the type of electronic component mounted on the first control means 18 to appropriately adjust the pressurizing current, so that various types of electronic components are provided. The component can be pressed onto the substrate with an appropriate pressure.

By raising the electronic component suction nozzle 12, the electronic component 26 is released on the substrate 30, and the mounting operation is completed. Thereafter, the mounting of the electronic components is similarly repeated.

Next, the operation of the electronic component mounting apparatus 10 when mounting heavy electronic components on a substrate will be described.

When a heavy electronic component is mounted on a substrate, only an operation when the electronic component is mounted on the substrate is different from a case where a light electronic component is mounted on the substrate, and other operations are light. The description is omitted because it is the same as the case where electronic components are mounted.

When placing heavy electronic components on a substrate,
As in the case where the light electronic component is placed on the substrate 30, the electronic component 26 is positioned above the substrate 30 while correcting the suction error, and then lowered, as shown in FIG. At the same time, the supply of the holding current from the first current supply means 14 to the first electromagnet 36 is interrupted, and the second current supply means is provided at a position where the electronic component 26 is close to the substrate 30. 16 supplies the buffer current to the second electromagnet 38.

The heavy electronic component 26 and the nozzle slider 3
2 is greater than or equal to the attractive force due to the negative pressure, so that even if the supply of the holding current from the first current supply means 14 to the first electromagnet 36 is interrupted, the electronic component 26 The nozzle slider 32 is held at the protruding position without being retracted.

When the electronic component 26 is further lowered, the electronic component 26 comes into contact with the substrate 30 and the nozzle slider 32 retracts to prevent the electronic component 26 from being damaged.

From the second current supply means 16 to the second
By supplying the buffer current to the electromagnet 38, the combined force of the urging force of the nozzle slider 32 by the second electromagnet 38 and the attraction force due to the negative pressure, and the gravity acting on the nozzle slider 32 and the electronic component 26 And the impact force when the electronic component 26 contacts the substrate 30 can be minimized.

Next, as in the case where a light electronic component is mounted on the substrate, the electronic component 26 is pressed against the substrate 30 and is released after being stabilized on the substrate 30 to complete the mounting operation.

Thereafter, the mounting of the electronic parts is similarly repeated.

In the embodiment of the present invention, the magnetic member 42 is a component of the nozzle slider 32. However, the present invention is not limited to this. A magnetic member that moves in the axial direction integrally with the nozzle slider may be used.

In the embodiment of the present invention, the first electromagnet 36 is arranged such that the first magnetic neutral position of the nozzle slider 32 is on the protruding side from the protruding position. The present invention is not limited to this, and the first electromagnet 36 may be arranged so that the second magnetic neutral position and the projecting position coincide with each other.

Further, in the embodiment of the present invention, the first and second current supply means 14 and 16 include a current supply device capable of supplying an intermittent current by pulse width modulation. The present invention is not limited to this, and may be, for example, a current supply unit including a variable resistor.

Further, in the embodiment of the present invention, as shown in FIGS. 3 and 4, the first current supply means 14 continuously increases and decreases the supply current to increase the holding current and the pressure. Although the current is supplied and cut off, the present invention is not limited to this. Only at the start of the supply of the pressurizing current, the supply current is continuously increased to supply the pressurizing current. You may do so.

When the electronic component has a sufficient strength, the pressurizing current may be supplied instantaneously. Similarly, the second current supply means 16 may supply and cut off the buffer current instantaneously.

Further, in the example of the present embodiment, the first control means 18 controls the first current supply means 14 according to the type of the electronic component to be mounted, and appropriately adjusts the pressurizing current. However, the present invention is not limited to this. When only electronic components having the same pressing force for stabilizing are mounted on the substrate, the first control unit 18 is used.
, The first current supply means 14 may supply a constant value of the pressurizing current.

Further, in the embodiment of the present invention, the absolute value of the holding current is 0 regardless of the weight of the mounted electronic component.
However, the present invention is not limited to this. When a heavy electronic component is mounted on a substrate, a holding current having an absolute value of 0 may be used.

Further, in the example of the present embodiment, the holding current has a constant value. However, the present invention is not limited to this.
The control means identifies the type of the electronic component, and when the electronic component is heavy, the absolute value of the holding current is small, and when the electronic component is light, the first current The supply means 14 may be controlled.

By doing so, it is possible to reduce the impact force when the electronic component contacts the substrate.

Further, in the example of the present embodiment, the buffer current is also a constant value, but the present invention is not limited to this. For example, a fourth control means is provided and the fourth control means is provided. The control means identifies the type of the electronic component, and when the electronic component is heavy, the absolute value of the buffer current is large, and when the electronic component is light, the second value is small so that the absolute value of the buffer current is small. May be controlled.

In this manner, various types of heavy electronic components can be mounted on the substrate with a small impact force.

Further, in the embodiment of the present invention, the electronic component suction nozzle 12 is connected to the first and second electromagnets 3.
6 and 38, the present invention is not limited to this. Even when only light electronic components are mounted and when heavy electronic components are mounted, the heavy electronic components have sufficient strength. The second electromagnet 3
An electronic component suction nozzle including only the first electromagnet 36 without providing the first electromagnet 36 may be used. In this case, the second current supply means 16 is unnecessary.

[0078]

According to the present invention, an electronic component can be placed on a substrate without being damaged, and can be pressed with an appropriate load.

[Brief description of the drawings]

FIG. 1 is a sectional view including a partial block diagram showing a structure of an electronic component suction nozzle according to an embodiment of the present invention.

FIG. 2 is a perspective view including a partial block diagram showing a main part structure of an electronic component mounting apparatus according to an embodiment of the present invention;

FIG. 3 is a graph showing a supply current value when a light electronic component is mounted in the example of the embodiment of the present invention.

FIG. 4 is a graph showing a supply current value when a heavy electronic component is mounted in the example of the embodiment of the present invention.

FIG. 5 is a sectional view showing the structure of a conventional electronic component suction nozzle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Electronic component mounting apparatus 12 ... Electronic component suction nozzle 14 ... 1st electric current supply means 16 ... 2nd electric current supply means 18 ... 1st control means 19 ... 2nd control means 32 ... Nozzle slider 32a ... Base end Part 32b: Tip part 34: Nozzle holder 36: First electromagnet 38: Second electromagnet

Claims (5)

[Claims] 1. A nozzle slider capable of vacuum-sucking electronic components at a distal end thereof by a negative pressure supplied from a base end side of a cylindrical body, and the nozzle slider protruding most toward the distal end side in an axial direction. An electronic component suction nozzle comprising: a nozzle holder slidably supported in a range between a protruding position and a retracted position most retracted to the base end side, wherein the electronic component is mounted on a substrate. In the component mounting apparatus, the nozzle slider is configured to be slidable in the axial direction by a magnetic force, and is capable of elastically biasing the nozzle slider toward a magnetic neutral position. An electromagnet positioned at a position protruding from the protruding position, and a holding current having an absolute value of 0 or more supplied to the electromagnet so that the nozzle slider protrudes against the suction force of the negative pressure. Current supply means capable of being held at the outgoing position, and the current supply means selectively supplies the pressing current and the holding current having an absolute value larger than the absolute value of the holding current to the electromagnet. An electronic component mounting device characterized by being made possible. 2. The apparatus according to claim 1, wherein said current supply means is configured to make a supply current value of said pressurizing current variable, and said urging force of said nozzle slider by said pressurizing current stabilizes an electronic component on a substrate. An electronic component mounting apparatus, wherein first control means for controlling the current supply means according to the type of electronic component to be mounted is provided so as to be equal to the pressing force for mounting. 3. The pressurizing current supply means according to claim 1, wherein at the start of said pressurizing current supply by said current supply means, a supply current absolute value of said current supply means continuously increases to become an absolute value of said pressurizing current. Thus, the electronic component mounting apparatus is provided with the second control means for controlling the current supply means. 4. The electromagnet according to claim 1, 2 or 3, wherein the electromagnet is provided as a first electromagnet, the current supply means is provided as a first current supply means, and the nozzle slider is oriented in a second magnetic force neutral position. The second magnetic force neutral position is a range in which the second magnetic force neutral position is on the retracted side of the protruding position, and the combined force of the biasing force by the second electromagnet and the suction force of the negative pressure Supplying a buffer current to the second electromagnet that balances the gravity acting on the nozzle slider and the electronic component vacuum-adsorbed to the nozzle slider,
An electronic component mounting device, comprising: a second current supply unit that can be interrupted. 5. The electronic component mounting apparatus according to claim 4, wherein the electronic component is vacuum-sucked at a tip end of the nozzle slider, and the electronic component is lowered from above the substrate to a predetermined mounting position on the substrate. When the component approaches the substrate, the supply of the buffer current from the second current supply means to the second electromagnet is started, and the electronic component is placed on the substrate while supplying the buffer current. An electronic component mounting method characterized by releasing.