JPH0997813A - Thermocompression bonding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermocompression bonding device allowing correct crimping of a joined part to a prescribed part. SOLUTION: A heater tool 18 thermocompression bonding an outer lead 65 of a TCP 64 to an electrode of an array substrate 70 is fixed to a supporting block 32 moving up and down between a crimping position wherein the tip part 38 presses the outer lead part 65 for being crimped to the electrode of the array substrate and a standby position separating from the TCP by an elevating mechanism. A pressure mechanism 35 having a pressure member 44 is mounted on the supporting block for moving up and down while being interlocked to the heater tool 18. When the heater tool 18 moves from the standby position to the crimping position, the pressure member presses the TCP so as to press down the outer lead part 65.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermocompression bonding apparatus for electrically connecting, for example, an electrode substrate of a liquid crystal display device and a printed wiring board having electronic components mounted thereon by pressure.

[0002]

2. Description of the Related Art In recent years, flat panel display devices typified by liquid crystal display devices have the advantages of thinness, light weight and low power consumption.
It is widely used as a display device such as a personal computer or a word processor, a TV display device, or a projection type display device.

Among them, an active matrix type display device in which a switching element is electrically connected to each pixel electrode is capable of obtaining a good display image without crosstalk between adjacent pixels. Development is underway.

Generally, an active matrix type liquid crystal display device has an array substrate and a counter substrate which face each other, and a liquid crystal composition is sealed between these substrates via an alignment film. The array substrate has a plurality of signal lines and a plurality of scanning lines arranged in a matrix on a glass substrate,
An image electrode is arranged near each intersection of the signal line and the scanning line via a thin film transistor (hereinafter referred to as a TFT) as a switching element.
Further, an auxiliary capacitance line that is substantially parallel to the scanning line is provided on the glass substrate, and an insulating film is interposed between the auxiliary capacitance line and the pixel electrode so that an auxiliary capacitance is formed between them. ing.

The counter substrate is provided with a matrix-shaped light-shielding film for shielding light around the TFT and the pixel electrode on a glass substrate, and a transparent counter-electrode is provided on the light-shielding film via an insulating film. .

Each signal line and each scanning line of the array substrate is
Driving for driving a display panel through a flexible printed wiring board or a TAB (Tape Automated Bonding) component such as a tape carrier package (hereinafter referred to as TPC) in which a driving element is arranged on a carrier tape. It is electrically connected to the circuit board.

Generally, the array substrate and the TAB component are connected to each other by thermocompression bonding using a thermocompression bonding device with an anisotropic conductive film having conductive particles dispersed in an adhesive resin sandwiched therebetween. Done by

The thermocompression bonding head device of the thermocompression bonding device includes a thermocompression bonding head that presses the lead portion of the TAB component from above in a heated state. Generally, this thermocompression bonding head comprises a substantially U-shaped heater tool having a pair of legs extending in parallel with each other and a tip having one end of each leg connected to each other. Then, the tip portion of the heater tool is pressed in parallel with the end portion of the TAB component and the array substrate.

[0009]

In order to securely crimp all of the many outer leads of the TAB component to the electrodes of the array substrate by using the thermocompression bonding head as described above,
It is necessary to uniformly press the outer lead portion of the AB component with the heater tool. Therefore, the parallelism of the tip of the heater tool with respect to the array substrate is adjusted and maintained with extremely high accuracy.

However, in the bending TAB which has been actively used in recent years, that is, in the TAB which is incorporated in a liquid crystal display device in a state where the printed wiring board is bent, the distance from the driving element to the outer lead portion is small. In a relatively long TAB component, the outer lead portion may be three-dimensionally deformed, for example, wavy.

When such an outer lead portion which is deformed in a wave shape is overlapped and arranged at a predetermined position of the array substrate, the outer lead portion does not uniformly contact the array substrate and is partially floated. Therefore, when the deformed outer lead portion is thermocompression-bonded by the heat tool, the floating portion is pressed by the heat tool and extends, and at that time, a position shift occurs with respect to the array substrate. Therefore, it becomes difficult to accurately connect each outer lead to the corresponding electrode on the array substrate side.

When the outer lead portion of the TAB component is thermocompression-bonded to the electrode of the circuit board by using solder, the heater tool is pressed against the outer lead portion and then the heater tool is pulled up while the solder is melted. There is a risk that the parts may float and connection failure may occur. The present invention has been conceived in view of the above points, and an object thereof is to provide a thermocompression bonding apparatus capable of reliably crimping a bonded portion to a predetermined portion.

[0013]

In order to achieve the above object, a thermocompression bonding apparatus for thermocompression bonding a jointed portion of a connecting member, which is arranged to overlap a predetermined portion of a connection target member, to the predetermined portion. A thermocompression-bonding device according to claim 1, wherein a heater tool having a tip end portion that abuts against the jointed portion, and a crimping position where the heater tool presses the jointed portion by the tip end portion and crimps the predetermined portion. An elevating mechanism that elevates and lowers between a standby position separated from the joined portion and an elevator mechanism that can be moved up and down in conjunction with the heater tool. When the heater tool moves from the standby position to the crimping position, A pressing means for pressing the vicinity of the joined portion against the connection target member with a predetermined pressure is provided.

According to the thermocompression bonding apparatus having the above-mentioned structure, when the heater tool is lowered from the standby position toward the crimping position during thermocompression bonding of the jointed portion to the predetermined portion, first, the pressing means covers the joint member. It abuts in the vicinity of the joint and presses the joint to the predetermined portion. In this state, the heater tool descends to the crimping position, presses the portion to be joined toward the predetermined portion, heats it, and performs thermocompression bonding.

The pressing means is provided with an elastic member that abuts on the portion in the vicinity of the joined portion and uniformly pushes the joined portion. As the elastic member, for example, a belt-shaped or wire-shaped elastic member suspended from a support block to which the heater tool is fixed is used.

Further, according to another thermocompression bonding apparatus of the present invention, the pressing means includes a pressing member having a pressing portion, and the pressing member is relative to the support block to which the heater tool is fixed. It is provided to be movable. Then, when the pressing portion of the pressing member comes into contact with the portion in the vicinity of the joined portion, the load of the pressing portion fixed to the pressing member is applied to the pressing portion as a pressing force.

According to the thermocompression bonding apparatus of the eighth aspect of the present invention, the thermocompression bonding apparatus in which the outer lead portions of the printed wiring board on which the electronic component is mounted are superposed on the electrodes provided side by side on the substrate by thermocompression bonding. A heater tool having a tip end portion capable of abutting the outer lead portion, a heater tool having a tip end portion that presses the outer lead portion and presses the outer lead portion to the electrode, and a standby position for separating from the lead portion. An elevating mechanism for elevating and lowering between a position and a heater tool are provided so as to be able to ascend and descend, and when the heater tool moves from the standby position to the crimping position, a portion near the outer lead portion is predetermined on the substrate. It is characterized in that it is provided with a pressing means for pressing with the pressure of.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 schematically shows the whole thermocompression bonding apparatus according to this embodiment used for manufacturing a liquid crystal display device.

As shown in FIG. 1, the thermocompression bonding apparatus includes a base 1
0 and a support frame 12 mounted on the base. An XY table 14 is provided on the upper surface of the base 10, and a stage 16 on which a liquid crystal panel, which will be described later, is placed is provided on the XY table.

A head unit 20 having a heater tool 18 described later is provided above the stage 16. The head unit 20 is attached to a movable base 24 via an air cylinder 22 that functions as a lifting mechanism, and the movable base 24 is provided in a horizontal frame 26 that extends horizontally above the stage 16 in the support frame 12. .
As a result, the head unit 20 can move up and down with respect to the stage 16.

In addition, an X-
Y table 14, air cylinder 22, heater tool 18
An operation panel 28 for controlling the operations of the above is provided.
As shown in FIG. 2, the head unit 20 includes a connecting plate 23.
A plate-shaped base portion 30 fixed to the air cylinder 22 via a support, and a rectangular parallelepiped support block 3 supported by the base portion.
2, a heater tool 18 fixed to the support block, and a holding mechanism 35 functioning as a holding means. The support block 32 is attached to the base portion 30 in a positionally adjustable manner by a support shaft 37 screwed into the base portion 30 through the support block.

The heater tool 18 has a pair of leg portions 36 that are parallel to each other and are opposed to each other at a predetermined distance, and a tip portion 38 that connects one ends of these leg portions to each other, and is formed in a substantially U shape. ing. The bottom surface 38a of the tip portion 38 is formed flat and extends horizontally. The heater tool 18 is made of, for example, iron, and the tip end portion 38 is made sufficiently thin so as to have the highest electric resistance. The width of the tip portion 38 is set to about 20 to 30 mm.

The heater rule 18 is detachably fixed to the support block by screwing the pair of legs 36 to the shank 40 fixed to the lower surface of the support block 32. The shank 40 is formed by plating a surface of a conductive material such as copper with gold, and is connected to a pulse power source (not shown) through a current supply line 42. By supplying a pulse current from this pulse power source, the heater tool 18 is energized via the shank 40, and the tip portion 38 of the heater tool having high electric resistance is instantly heated.

The pressing mechanism 35 has, for example, a diameter of 0.8 mm.
Is provided with a pressing member 44 formed by bending the wire into a substantially U shape. The pressing member includes a pair of parallel vertical portions 45a extending in the vertical direction of the heater tool 18, that is, a substantially vertical direction, and a pressing portion 45b connecting the lower ends of the vertical portions to each other and extending horizontally. have.

A pressing portion 46 formed of a cylindrical weight is fixed to the upper end of each vertical portion 45a and extends in the vertical direction. The weight of each support portion 46 is set to about 40 g, for example. Brackets 48 forming a support portion are fixed to both side surfaces of the support block 32, respectively. A through hole 50 extending in the vertical direction is formed in each bracket 48, and the pressing portion 46 is slidably inserted into this through hole. Further, a flange 46a that functions as a stopper is formed at the upper end of each pressurizing portion 46.

Therefore, the pressing member 44 is supported by the bracket 48 via the pair of pressing portions 46 so as to be movable up and down, that is, to be movable in the vertical direction of the heater tool 18. The pressing member 44 is normally held in a lowered position where the flange 46a abuts on the bracket 48, and the pressing portion 45b is positioned diagonally below the heater tool 18.

Next, the thermocompression bonding operation of the thermocompression bonding apparatus configured as described above will be described. For example, as shown in FIG. 3, a tape carry package (hereinafter referred to as TCP) as a TAB component is mounted on the array substrate 70 of the liquid crystal panel 68.
A case where the drive circuit board 72 is connected to the TPC will be described. The array substrate 70 is
The connection target member and the TCP 64 form a connection member.

As shown in FIG. 4, first, a TC in which a driving element 62 is mounted on a flexible printed wiring board 60.
P64 is prepared, and an anisotropic conductive film 66 is attached on a large number of outer leads 65 provided on one end side of the TCP.
The anisotropic conductive film 66 is formed in a sheet shape, for example, by dispersing conductive particles such as nickel and solder in a thermosetting resin.

Next, as shown in FIG. 3, a liquid crystal panel 68.
A plurality of predetermined electrodes and TCs provided on the array substrate 70 of
While accurately aligning the plurality of outer leads 65 of P64, one end of the TCP 64 is superposed on the array substrate 70 with the anisotropic conductive film 66 interposed therebetween. Then, in this state, the liquid crystal panel 68 and the TCP 64 are placed on the stage 16 of the thermocompression bonding apparatus.

Subsequently, as shown in FIGS. 2 and 3, the XY table 14 is operated via the operation panel 28,
The stage 16 is moved to a position where the joint between the liquid crystal panel 68 and the TCP 64 is aligned with the tip 38 of the heater tool 18. In this state, the support block 30 of the head unit 20 is located in a raised position, and the heater tool 1
8 is held at a standby position in which the tip portion 38 thereof is separated from the TCP 64. Further, the pressing mechanism 35 is also held in the raised position, and the pressing portion 45b of the pressing member 44 is
In the vicinity of the outer leads 65 of 64, they face the surface of the array substrate 70 in parallel.

After that, when the air cylinder 22 is driven to lower the head unit 20, as shown in FIG. 5, first, the pressing portion 45b of the pressing member 44 prints in the vicinity of the outer lead 65 as a joined portion. It contacts the upper surface of the wiring board 60. Then, when the head unit 20 is further lowered, the flanges 46a of the pressurizing portions 46 are separated from the bracket 48 upward. As a result, the load of the pressing portion 46 is applied to the pressing member 44 as a pressing force, and the pressing portion 4 is pressed.
5b presses the printer wiring board 60 together with the outer leads 65 against the surface of the array substrate 70 by the pressing force.
Therefore, even when the printed wiring board 60 is three-dimensionally deformed due to wrinkles, undulations, etc. in the vicinity of the outer leads 65, the printed wiring board 60 is returned to a flat state by the pressing portion 45b of the pressing member 44, and the outer leads Accurately adheres to the corresponding electrodes on the array substrate 70.

After that, when the head unit 20 is further lowered and the heater tool 18 is moved to the crimping position, the bottom surface 38a of the tip end portion 38 of the heater tool 18 is brought into contact with the outer lead 6.
The printed wiring board 60 is pressed against the back side of the printed circuit board 5 with a predetermined pressure. In this state, the pulsed power supply is energized for a predetermined time to heat the heater tool 18 so that the outer lead 65
Are thermocompression bonded to the corresponding electrodes on the array substrate 70.

Then, after the heater tool 18 has cooled to a predetermined temperature, the air cylinder 22 is driven to raise the head unit 20. Then, first, the heater tool 18 is separated upward from the TCP 64. Then, when the head unit 20 further rises, each bracket 48
Comes into contact with the flange 46a of the pressurizing portion 46, and thereafter, the pressing member 44 ascends together with the heater tool 18, and the TCP64
Separate from.

By the above operation, the resin of the anisotropic conductive film 66 is heated and cured, and the TCP 64 is fixed to the array substrate 70. At the same time, the electrodes of the array substrate 70 and the TCP 64 are formed by the conductive particles dispersed in the resin of the anisotropic conductive film 66.
The outer leads 65 are electrically connected.

The connection between the plurality of outer leads provided on the other end of the TCP 64 and the electrodes of the drive circuit board 72 is performed by the same operation as described above. However, in this case, solder is used instead of the anisotropic conductive film 66.

According to the thermocompression bonding apparatus having the above-described structure, the head unit 20 has the pressing mechanism 35, and when performing the thermocompression bonding, the pressing portion of the pressing member 44 precedes the heater tool 18. 45b comes into contact with a portion of the TCP 64 in the vicinity of the outer lead 65 to press these outer leads against the electrodes of the array substrate 70 with a predetermined pressing force.

Therefore, even if the outer lead portion of the printed wiring board is deformed such as wrinkles or undulations, the deformation is eliminated by pressing it by the pressing member,
The outer leads can be brought into close contact with the electrodes on the array substrate side while being accurately aligned. As a result, the head tool 18 can accurately thermocompress the outer leads 65 of the TCP 64 to the corresponding electrodes of the array substrate or the drive circuit substrate.

6 and 7 show a head unit 20 of a thermocompression bonding apparatus according to the second embodiment of the present invention. According to the second embodiment, the pressing member 44 of the pressing mechanism 35 is, for example, a heat resistant resin film such as a polyimide film, stainless steel having a film thickness of 0.3 mm or less, phosphor bronze for springs, or the like. It is composed of a band-shaped elastic member formed of the metal sheet.

Both ends of the pressing member 44 are fixed to both side surfaces of the support block 32 with screws. Thereby,
The pressing member 44 is supported by being suspended from the support block 32, and the lower end portion of the pressing member is curved below an arc and extends below the heater tool 18.

The other structure is the same as that of the above-mentioned embodiment, and the same portions are denoted by the same reference numerals and detailed description thereof will be omitted. According to the second embodiment having the above configuration, when the head unit 20 is lowered by the air cylinder 22 as the elevating mechanism during the thermocompression bonding operation, first, the lower end portion of the pressing member 44 is the drive element 6 of the TCP 64.
Abut 2. As a result, the lower end of the pressing member 44 elastically deforms along the drive element 62, and presses the TCP 64 against the array substrate 70 via the drive element 62 by its own elasticity. Therefore, even if the printed wiring board 60 of the TCP 64 is deformed such as wrinkles or undulations, the pressing member 44 presses the deformation to remove the outer lead 65 accurately from the corresponding electrode of the array substrate. It can be closely attached in a positioned state.

Subsequently, when the head unit 20 is further lowered, the bottom surface 28a of the tip end portion 38 of the heater tool 18 is pressed against the printed wiring board 60 from the back side of the outer lead 65 with a predetermined pressure. In this state, the pulsed power supply is energized for a predetermined time to heat the heater tool 18, whereby the outer leads 65 are thermocompression-bonded to the corresponding electrodes on the array substrate 70, respectively.

Also in the second embodiment constructed as described above, as in the case of the above-mentioned embodiment, even when the outer lead portion is deformed such as wrinkles or undulations, T
The outer leads 65 of the CP 64 can be accurately thermocompression-bonded to the electrodes of the corresponding array substrate or drive circuit substrate.

8 and 9 show a head unit 20 of a thermocompression bonding apparatus according to the third embodiment of the present invention. According to the third embodiment, the pressing member 44 of the pressing mechanism 35 is configured by using a plurality of, for example, six elastic wires 80.

Both ends of each wire 80 are screwed and fixed to both side surfaces of the support block 32 via mounting plates 82. These wires 80 have the same length as each other, and are attached side by side in parallel with each other to form a band shape as a whole. Each wire 80 is supported by being suspended from the support block 32, and the lower end portion of the wire 80 extends below the heater tool 18 in a curved arc shape.

The other structure is the same as that of the above-mentioned embodiment, and the same reference numerals are given to the same portions and the detailed description thereof will be omitted. According to the third embodiment having the above configuration, when the head unit 20 is lowered by the air cylinder 22 as the lifting mechanism during the thermocompression bonding operation, first, the lower ends of the plurality of wires 80 are the drive elements 62 of the TCP 64. And abuts on the upper surface of the printed wiring board 60. As a result, the lower ends of the plurality of wires 80 are elastically deformed along the drive element 62 or along the printed wiring board 60, and the TCP 64 is arrayed via the drive element 62 and the printed wiring board 60 by its own elasticity. Hold against 70.

Therefore, the TCP64 printed wiring board 60
Even when a wrinkle, a swell, or the like is deformed, the deformation is removed by pressing the pressing member 44 composed of the plurality of wires 80, and the outer lead 65 is accurately positioned with respect to the corresponding electrode of the array substrate. Can be adhered in the state.

Then, when the head unit 20 is further lowered, the bottom surface 28a of the tip end portion 38 of the heater tool 18 is pressed against the printed wiring board 60 from the back side of the outer lead 65 with a predetermined pressure. In this state, the pulsed power supply is energized for a predetermined time to heat the heater tool 18, whereby the outer leads 65 are thermocompression-bonded to the corresponding electrodes on the array substrate 70, respectively.

Also in the third embodiment configured as described above, as in the above-described embodiments, even when the outer lead portion is deformed such as wrinkles or undulations, T
The outer leads 65 of the CP 64 can be accurately thermocompression-bonded to the electrodes of the corresponding array substrate or drive circuit substrate. Particularly, according to the present embodiment, TCP is provided at a plurality of positions.
Since 64 can be pressed down, the deformation of the printed wiring board 60 can be removed more reliably, and more accurate crimping is possible.

The present invention is not limited to the above-described embodiments, but can be variously modified within the scope of the present invention. For example, the material of the elastic member that constitutes the pressing member is not limited to the above-described embodiment, but various selections can be made as necessary, and rubber, sponge, or the like can also be used.
Further, the shape of the pressing member can be variously selected as required.

[0050]

As described above in detail, according to the present invention, by providing the pressing means for pressing the joined portion against the connection target member, the joined portion can be accurately crimped to a predetermined portion. An object is to provide a thermocompression bonding device.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing an entire thermocompression bonding apparatus according to an embodiment of the present invention with a part thereof broken away.

FIG. 2 is a front view and a sectional view of a head unit of the thermocompression bonding apparatus.

FIG. 3 is a liquid crystal panel bonded by the thermocompression bonding device,
FIG. 3 is a perspective view showing a TCP and a drive circuit board.

FIG. 4 is an enlarged perspective view showing the TCP.

FIG. 5 is a front view and a side view of the head unit in a state where the head unit is lowered to a thermocompression bonding position.

FIG. 6 is a front view and a sectional view of a head unit according to a second embodiment of the invention.

FIG. 7 is a front view and a side view of the head unit according to the second embodiment in a state where the head unit is lowered to a thermocompression bonding position.

FIG. 8 is a front view and a sectional view of a head unit according to a third embodiment of the invention.

FIG. 9 is a front view and a side view of the head unit according to the third embodiment in a state where the head unit is lowered to a thermocompression bonding position.

[Explanation of symbols]

 18 ... Heater tool 20 ... Head unit 22 ... Air cylinder 32 ... Support block 35 ... Pressing mechanism 38 ... Tip part 44 ... Pressing member 45a ... Vertical part 45b ... Pressing part 46 ... Pressing part 48 ... Bracket 60 ... Printed wiring board 62 Drive element 64 TCP 65 Outer lead 66 Anisotropic conductive film 68 Liquid crystal panel 70 Array substrate 72 Drive circuit board 80 Wire

Claims (8)

[Claims] 1. A thermocompression bonding apparatus for thermocompression bonding a joined portion of a connecting member, which is arranged in a predetermined portion of a connection target member, to the prescribed portion, the tip portion being capable of contacting the joined portion. A heater tool; an elevating mechanism for elevating and lowering the heater tool between a crimping position where the tip portion presses the joined portion to be crimped to the predetermined portion and a standby position which is separated from the joined portion; and the heater tool When the heater tool moves from the standby position to the crimping position, the vicinity of the joined portion of the connection member is pressed to move the joined portion to the connection target portion by a predetermined distance. A thermocompression bonding apparatus comprising: a pressing unit that presses with pressure. 2. The thermocompression bonding apparatus according to claim 1, wherein the pressing means has an elastic member provided adjacent to the heater tool. 3. A support block that supports the heater tool and is moved up and down by the elevating mechanism, and the pressing means has an elastic member attached to the support block. The thermocompression bonding apparatus according to claim 1. 4. The holding means is suspended from the support block in a state where both ends are fixed to the support block, and the lower end portion is elastically deformed by abutting against the connecting member so that the joined portion is fixed. The thermocompression bonding apparatus according to claim 3, further comprising a band-shaped elastic member to be pressed. 5. The pressing means is suspended from the support block in a state where both ends are fixed to the support block, and its lower end is brought into contact with the connecting member to elastically deform so that the joined portion is fixed. The thermocompression bonding apparatus according to claim 3, further comprising a wire-shaped elastic member to be pressed. 6. The holding means is hooked down from the support block in a state where both ends are fixed to the support block, and the lower end portion is elastically deformed by coming into contact with the connection member to elastically deform the connection member. The thermocompression bonding apparatus according to claim 3, further comprising a plurality of wire-shaped elastic members that press down a plurality of portions. 7. A support block that supports the heater tool and is moved up and down by the elevating mechanism, wherein the pressing means includes a pair of vertical portions extending in the up-and-down direction of the heater tool, respectively. A pressing member that connects the lower ends of the vertical portions and has a pressing portion that faces the vicinity of the joined portion in parallel, and a pressing member that is fixed to the upper ends of the vertical portions and that has a predetermined pressing force. A pair of pressurizing sections for applying pressure, and a pair of support sections fixed to the support block and movably supporting the upper ends of the vertical sections along the vertical direction of the heater tool. In the pressing member, while the heater tool moves from the standby position to the crimping position, the pressing portion comes into contact with a portion in the vicinity of the joined portion, and then the upper end portion of the vertical portion has the support block. By moving relative to the click, thermocompression bonding apparatus according to the pressing force to claim 1, characterized in that applied to the pressing portion. 8. A plurality of electrodes arranged side by side on a substrate,
A thermocompression bonding apparatus for stacking and thermocompressing outer lead portions of a printed wiring board on which electronic components are mounted, comprising: a heater tool having a tip portion capable of abutting the outer lead portion; An elevating mechanism that elevates and lowers between a crimping position for pressing the lead part to be crimped to the electrode and a standby position separated from the lead part; and an elevating mechanism that is interlocked with the heater tool. A thermocompression bonding device, comprising: pressing means for pressing the printed wiring board including the electronic component to press the outer lead portion against the substrate with a predetermined pressure when moving from the standby position to the pressure bonding position. .