KR20130071229A - Mask supplying system - Google Patents

Abstract

PURPOSE: A mask supply system is provided to easily establish automation by simplifying a layout around a chamber. CONSTITUTION: An OHT(Over Head Transfer) rail(110) has a curved rail unit(110b). The OHT rail is arranged in an upper part of the chamber. A mask supply table(120) has a driving module. The driving module is movably engaged with the OHT rail. The mask supply table supplies a mask into the chamber.

Description

{Mask supplying system}

The present invention relates to a mask supply system, and more particularly, to a mask supply system that can be easily manufactured at a lower cost than the conventional apparatus, and can smoothly run the curved rail portion of the OHT rail even if the mask supply carriage becomes larger or heavier To a mask supply system capable of increasing the supply efficiency of the mask.

Organic Light Emitting Display (OLED), one of flat panel display devices, is an ultra-thin display device that realizes color images by self-emission of organic materials. It is attracting attention as a promising display device.

The organic light emitting display OLED includes an anode, a cathode, and organic layers interposed between the anode and the cathode. Here, the organic layers include at least a light emitting layer and may further include a hole injecting layer, a hole transporting layer, an electron transporting layer, and an electron injecting layer in addition to the light emitting layer.

The organic electroluminescent display device can be divided into a polymer organic electroluminescent device and a low molecular weight organic electroluminescent device depending on an organic film, particularly a material forming the light emitting layer.

In order to realize a full color, a light emitting layer must be patterned. In this case, a direct patterning method using FMM (Fine Metal Mask, hereinafter referred to as a mask), a method using LITI (Laser Induced Thermal Imaging) A method using a color filter may be applied.

When a large OLED is manufactured by applying a mask method, a so-called horizontal type upward deposition method in which a substrate and a patterned mask are horizontally disposed in a chamber and then deposited is applicable.

The horizontal upward deposition method is a method of aligning a substrate disposed horizontally with respect to a bottom surface of a chamber or the like and then bonding the mask and depositing an organic material on a large substrate in a horizontal state.

However, as the size of the OLED increases, the size and weight of the mask are becoming larger and larger. In this case, since the mask is deflected in the direction of gravity, it is difficult to closely adhere the mask to the substrate. There is a difficult problem.

Therefore, in recent years, a technique for placing a substrate and a mask in a vertical direction and then bonding them, and then depositing an organic material has been studied, and the applicant has many prior applications for these techniques, and some have been registered and applied.

On the other hand, apart from the above-described horizontal and vertical, any type of mask must be supplied into the chamber, so that a corresponding process through the mask, for example, a deposition process on a substrate, can be performed.

However, until now, a system in which a mask, which is transported along the floor in a clean room by a separate robot, is supplied to the side surface of the chamber is often installed, so that it is not economical to utilize the space in the clean room The layout of the periphery of the chamber may become complicated, thereby making it difficult to implement automation.

Actually, considering the clean room, considering that the upper area of the chamber is a wide empty space which is not used differently, if the mask supply system is constructed by utilizing such a space, various problems that have been caused in the past can be solved do.

As an example of such a mask supply system, there is an OHT (overhead transfer) rail disposed in an upper region of a chamber provided in a clean room, a mask supply member which is movably coupled to the OHT rail to supply a mask into the chamber, Consider a mask supply system that includes a bogie.

In this case, if all of the OHT rails are linear rails or straight rails, there is no difficulty in running the mask feeder carriage, but considering that the curved rail portion is included in the OHT rail, the mask feeder carriage moves along the curved rail portion of the OHT rail In order to run smoothly, separate measures must be accompanied.

For example, when the mask supply carriage travels along the curved rail portion of the OHT rail, one of the wheels of the mask supply carriage may float on the OHT rail. Such a method is possible when the mask traveling carriage is small.

However, as the weight and the size of the mask increase, the weight and the size of the mask supply carriage and the parts associated therewith become larger as the mask weight and the size increase. Therefore, when such a large heavyweight mask supply carriage travels the curved rail portion of the OHT rail, To float on the curved rail of the OHT rail is not practical.

As an alternative to this, consider a method of using a dual rail on the curved rail part of the OHT rail and using four wheels on the driving shaft of the mask supply carriage to separate them into a straight rail driving wheel and a curved rail driving wheel, respectively It is possible.

However, an additional configuration for laying the dual rails and for applying the four wheels to the drive shaft of the mask supply carriage increases, resulting in an increase in the overall system construction cost. Therefore, an efficient alternative is needed in view of such problems.

Korea Patent Office Application No. 10-2005-0011334

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is, therefore, an object of the present invention to provide an OHT rail which can smoothly run a curved rail portion of the OHT rail, To provide a mask supply system.

According to an aspect of the present invention, there is provided an OHT (Over Head Transfer) rail having a curved rail portion and disposed in an upper region of a chamber provided in a clean room; And a mask supply bogie for supplying a mask into the chamber, wherein the traveling module includes an inner wheel that travels along an inner rail of the OHT rail, a wheel unit having an inner wheel and an outer wheel running along an outer rail of the OHT rail; And a wheel unit driving unit for driving the wheel unit, the wheel unit driving unit including a differential synchronizer for relatively adjusting a rotational speed between the inner wheel and the outer wheel.

The control unit may further include a controller for controlling operation of the wheel unit driving unit when the mask supply truck travels the curved rail unit of the OHT rail.

The control unit controls the operation of the differential locker provided in the wheel unit drive unit such that the speed of the outer wheel is faster than the speed of the inner wheel when the mask supply truck travels the curved rail portion of the OHT rail .

Wherein the wheel unit driving unit includes: a driving motor for generating power for driving the mask supply truck; And a driving shaft connected between the inner wheel and the outer wheel and rotated by the driving motor, the driving shaft being connected to the secondary synchronization unit.

The mask supply bogie may further include a bogie main body in which a gripping unit for gripping a mask supplied into the chamber is provided.

The gripping unit includes: a unit body; A gripper connected to the unit body in an upper region in the bogie body and gripping or releasing the upper end of the mask while approaching or separating from each other; A gripper up / down driver for driving the gripper up / down; And an anti dropper connected to the unit body on the opposite side of the gripper and operated together with the gripper to prevent a drop of the mask.

The wheel unit includes a front inner wheel running along an inner rail of the OHT rail and a front wheel provided on both sides of the front outer wheel running along an outer rail of the OHT rail. unit; And a rear wheel unit which is provided on both sides of a rear outer wheel that runs along an outer rail of the OHT rail and a rear inner wheel that runs along an inner rail of the OHT rail .

The traveling module includes a unit support for supporting the front wheel unit and the rear wheel unit; A front bearing for rotatably connecting the front wheel unit and the unit support; A rear bearing for rotatably connecting the rear wheel unit and the unit support; And a connector connecting the unit support and the trolley body in the central region of the unit support.

The front wheel unit and the rear wheel unit may have the same structure.

Wherein both the front wheel unit and the rear wheel unit are disposed at lower positions than the inner wheel and the outer wheel respectively provided on the front wheel unit and the rear wheel unit and are guided on the side surface of the OHT rail, A side guide roller for blocking the deviation; And a direction adjusting roller provided at a higher position than the inner wheel and the outer wheel, respectively, provided to the front wheel unit and the rear wheel unit.

Both the front wheel unit and the rear wheel unit may further include a non-contact type power supply unit that receives power from a non-contact type and supplies power to the driving motor.

The traveling module may further include a buffer stopper elastically buffering a collision of the mask supply bogie.

And a rail hanger for supporting the OHT rail.

The chamber may be an evaporation chamber for performing an evaporation process of an organic light emitting display (OLED) through the mask. In an upper region of the evaporation chamber, A mask loading port may be further provided.

According to the present invention, it is possible to easily manufacture a mask with less cost than the conventional mask, and even if the mask supply bogie is made larger or heavier, the curved rail portion of the OHT rail can smoothly run and the supply efficiency of the mask can be improved.

1 is a schematic plan view of a mask supply system according to an embodiment of the invention.
FIG. 2 is an enlarged perspective view of main parts of FIG. 1. FIG.
3 and 4 are a plan view and a front view, respectively, of Fig.
5 to 8 are enlarged views of the areas A to D shown in Figs. 3 and 4, respectively.
9 is a cross-sectional view taken along the line EE of Fig.
10 is an enlarged view of the main part of Fig.
11 is a control block diagram of a mask supply system according to an embodiment of the present invention.
12 is a diagram schematically illustrating a process of supplying a mask to a deposition chamber in a mask supply cart.
13 is an enlarged view illustrating main parts of FIG. 12.

In order to fully understand the present invention, operational advantages of the present invention, and objects achieved by the practice of the present invention, reference should be made to the accompanying drawings and the accompanying drawings which illustrate preferred embodiments of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like reference symbols in the drawings denote like elements.

FIG. 1 is a schematic plan view of a mask supply system according to an embodiment of the present invention, FIG. 2 is an enlarged main part view of FIG. 1, FIGS. 3 and 4 are respectively a plan view and a front view of FIG. 2, Fig. 8 is an enlarged view of the area A to D shown in Figs. 3 and 4, Fig. 9 is a cross-sectional view taken along the line EE of Fig. 4, Fig. 10 is an enlarged view of the main part of Fig. 12 is a view schematically showing a process of supplying a mask from a mask supply bogie to a deposition chamber, and Fig. 13 is a schematic view showing a main part enlarged view of Fig. 12 to be.

As shown in these drawings, the mask supply system of the present embodiment is provided with a curved rail part 110b, and is provided with an OHT (Over Head Transfer) device disposed in an upper area of the chamber 1 provided in a clean room, A rail 110 and a travel module 150 which is coupled to the OHT rail 110 to be able to travel and a mask supply truck 120 for supplying the mask M into the chamber 1.

The traveling module 150 includes an inner wheel 161 and an inner wheel 161 running along the inner rail 111 of the OHT rail 110 and an outer wheel 112 running along the outer rail 112 of the OHT rail 110. [ Wheel units 160 and 170 having outer wheels 162 and 172 and inner and outer wheels 162 and 172 and a differential synchronizer 193 for relatively adjusting a rotational speed between the inner wheels 161 and 171 and the outer wheels 162 and 172, And a wheel unit driver 190 for driving the wheel unit.

Since the mask supply system of the present embodiment includes the wheel unit driver 190 having the differential sync driver 193, the mask supply system of the present embodiment can be manufactured easily and at a lower cost than the conventional one, The curved rail portion 110b of the OHT rail 110 can smoothly run, and the supply efficiency of the mask M can be increased.

Hereinafter, for convenience of explanation, the wheel units 160 and 170 will be referred to as a front wheel unit 160 and a rear wheel unit 170, respectively, and the inner wheels 161 and 171 and the outer wheels 162 and 172 will be described in detail, The front inner wheel 161 and the rear inner wheel 171, and the front outer wheel 162 and the rear outer wheel 172, respectively.

First, referring to the chamber 1, the chamber 1 according to the present embodiment includes an evaporation chamber 1 for performing an evaporation process of an organic light emitting display (OLED) through a mask M, to be.

However, the scope of the present invention is not limited thereto. Therefore, the chamber 1 may be a chamber for a process of depositing a flat panel display element other than an OLED, that is, an LCD and a PDP. In addition, the chamber 1 may be a vacuum chamber or various kinds of process chambers in which the mask M can be used in addition to the vapor deposition chamber 1.

1 and 12, an upper region of the deposition chamber 1 is provided with a mask loading port 2 to which a mask M supplied from a mask supply bogie 120 is loaded.

A plurality of mask loading slots 3 are formed in the mask loading port 2. The mask supply bogie 120 can load the mask M in the mask loading slot 3 of the corresponding mask loading port 2 while moving the mask M in the upper region of the chamber 1, The mask M can be taken out.

Inside the mask mounting slot 3, a mask supporting step 4 for stably supporting the lower end of the mask M is provided.

The OHT rail 110 is a track rail disposed in the upper region of the chamber 1 in the clean room. When the mask M is supplied while the OHT rail 110 is laid on the upper region of the chamber 1 and the mask supply bogie 120 is moved using the OHT rail 110, Can be economically utilized.

In particular, unlike the conventional method, the layout around the chamber 1 can be simplified, and automation construction can be facilitated.

Depending on the actual production line of the manufacturer, the number of chambers 1 in the clean room or the position of the chamber 1 may vary. Therefore, the OHT rail 110 can be appropriately designed according to the situation of the clean room including the shape shown in FIG.

The OHT rail 110 may have a straight rail part 110a and a curved rail part 110b regardless of the form of the OHT rail 110. The mask supply rail 120 of the present embodiment has the following structural features It is possible to carry or supply the mask M while smoothly traveling from the linear rail part 110a to the curved rail part 110b.

As shown in FIGS. 12 and 13, a rail hanger 115 is provided on the OHT rail 110 to support the OHT rail 110.

The shape of the OHT rail 110 shown in FIG. 1 is one embodiment, and the scope of the present invention can not be limited to the drawings.

2, 9, and 13, the mask supply truck 120 includes a truck main body 130, a traveling module 150 that connects the truck main body 130 to the OHT rail 110 so as to run freely, .

The bogie body 130 is a kind of cabinet in the mask supply bogie 120 and includes therein a gripping unit 140 for gripping a mask M supplied into the chamber 1 ).

Referring to FIG. 13, the gripping unit 140 includes a unit body 141, a gripper 142, a gripper up / down driving unit 143, And includes a dropper 144 (anti dropper).

The unit body 141 forms an appearance of the gripping unit 140. [ Normally, the unit body 141 is not covered by the truck body 130.

The gripper 142 is connected to the unit body 141 in an upper region in the truck main body 130 and serves to grip or ungrip the upper end of the mask M while approaching or separating from each other.

The gripper up / down driving unit 143 is connected to the gripper 142 to drive the gripper 142 up / down. As the gripper up / down drive unit 143, a cylinder or an actuator may be applied, and the mask M may be supplied to the mask loading port 2 while being operated down, as shown in FIG.

The anti-dropper 144 is connected to the unit body 141 on the opposite side of the gripper 142 and is operated together with the gripper 142 to stop the drop of the mask M, And is prevented from dropping and falling.

At this time, at least one of the gripper 142 and the anti-dropper 144 may be applied as an electrostatic chuck for chucking the mask M by an electromagnetic force. When the gripper 142 and the anti-dropper 144 are applied as an electrostatic chuck, there is an advantage that the operation is simple and the structure is simple. However, the gripper 142 and the anti-dropper 144 may be manufactured by various structures other than the electrostatic chuck, such as an adsorption chuck or a bite structure.

10, the traveling module 150 mainly includes a front wheel unit 160, a rear wheel unit 170, a wheel unit driving unit 190, a unit support 180, and a buffer stopper 197 .

5 to 8, the front wheel unit 160 includes a front inner wheel 161 running along the inner rail 111 of the OHT rail 110, a front inner wheel 161 mounted on the OHT rail 110, And a front outer wheel 162 running along the outer rail 112 of the vehicle.

5 to 8, the rear wheel unit 170 includes a rear inner wheel 171 running along the inner rail 111 of the OHT rail 110, a rear inner wheel 171 disposed on the OHT rail 110, And a rear outer wheel 172 running along the outer rail 112 of the vehicle.

The structures of the front wheel unit 160 and the rear wheel unit 170 are the same except for their positions.

The wheel unit driving unit 190 serves to drive the front wheel unit 160 and the rear wheel unit 170.

The wheel unit drive unit 190 may be provided only in the front wheel unit 160, for example, so that the rear wheel unit 170 may be driven in a driven manner along the front wheel unit 160. However, in the present embodiment, since the front wheel unit 160 and the rear wheel unit 170 have the same structure, the wheel unit driving unit 190 is provided with the front wheel unit 160 and the rear wheel unit 170 They are provided in the same structure and driven independently.

5 to 8 and 10, the wheel unit driving unit 190 includes a driving motor 191 that generates power for driving the mask supply truck 120, a front inner wheel 161, And a driving shaft 192 connected to the front outer wheel 162 or the rear inner wheel 171 and the rear outer wheel 172 and driven by the driving motor 191, A differential locker 193 for relatively adjusting the rotational speed between the front inner wheel 161 and the front outer wheel 162 or between the rear inner wheel 171 and the rear outer wheel 172, And a control unit (not shown) for controlling the operation of the differential synchronizing unit 193 when the bogie 120 runs on the curved rail part 110b of the OHT rail 110. [

The differential gear unit 193 is a gear unit composed of a combination of a sun gear and a plurality of planetary gears. The gear ratio between the sun gear and the planetary gears causes the front inner wheel 161 and the front outer wheel 162 or the rear inner wheel 171 and the rear outer wheel 172 can be changed. This differential synchronizer 193 can be controlled by the control unit when the mask supply carriage 120 travels along the curved rail part 110b of the OHT rail 110. [

That is, when the mask supply carriage 120 travels along the curved rail part 110b of the OHT rail 110, the control part controls the speed of the front outer wheel 162 and the front inner wheel 161 to be higher than the speeds of the front inner wheel 161 and the rear inner wheel 171, And controls the operation of the differential synchronizer 193 so that the speed of the rear outer wheel 172 can be further increased.

When the mask supply bogie 120 travels along the curved rail part 110b of the OHT rail 110, one wheel of the mask supply bogie 120 must be lifted from the OHT rail 110 (Not shown) are laid on the curved rail part 110b of the OHT rail 110 and four wheels are applied to the driving shaft 192 of the mask supply carriage 120 to drive the linear rail driving wheel and the curved rail It is possible to solve the problems of the related art, such as using the wheel for driving partly.

5 to 8 and 10, both the front wheel unit 160 and the rear wheel unit 170, which are provided in the same structure as each other, include a side guide roller 194, a direction adjusting roller 195, And a power supply unit 196.

The side guide rollers 194 are guided on the side surface of the OHT rail 110 to prevent the departure of the rail of the travel module 150.

The side guide rollers 194 are disposed at a lower position than the front inner wheel 161 and the front outer wheel 162 or the rear inner wheel 171 and the rear outer wheel 172, That is, along the horizontal direction.

The direction adjusting roller 195 may be provided for direction adjustment of the traveling module 150. [ The direction adjusting roller 195 may be disposed at a higher position than the front inner wheel 161 and the front outer wheel 162 or the rear inner wheel 171 and the rear outer wheel 172. [

The non-contact type power supply unit 196 supplies power to the driving motor 191 in a non-contact manner.

The non-contact power supply unit 196 will be described with reference to Figs. 10 and 11. Fig. The noncontact type power supply unit 196 includes an induction rail 196a extended along the OHT rail 110 and a traveling module 150 arranged adjacent to the induction rail 196a without being in contact with the induction rail 196a. And a pickup unit 196b which is provided in the driving motor 191 and supplies a constant current to the driving motor 191 in a non-contact state by the electromagnetic induction principle.

Accordingly, when high frequency AC power is applied to the induction rail 196a, an electromotive force can be generated by the pickup unit 196b adjacent to the induction rail 196a by the electromagnetic induction law. This electromotive force is generated by the operation of the drive motor 191 Can be used as a power source.

11, the non-contact type power supply unit 196 includes a regulator 196c (REGULATOR) receiving a voltage (electromotive force) from the pickup unit 196b, a regulator 196c connected to the regulator 196c, And a power supply 196d (POWER SUPPLY) having a distribution circuit 196e for distributing the voltage to the power supply 191, 191.

With this structure, for example, when a regulator 196c receiving a voltage (electromotive force) from the pickup unit 196b adjacent to the induction rail 196a applies a DC 300V voltage to the power supply 196d, the power supply 196d can distribute the voltage to, for example, DC 12V, DC 24V, DC 48V, and the like, and supply the divided voltage to the driving motor 191. As in the present embodiment, if the distribution circuit 196e is integrally provided in the power supply 196d and the voltage from the regulator 196c is implemented as shown in Fig. 11 so as to be supplied with the power supply 196d, In addition, there is an advantage in that the maintenance is easy, the control becomes relatively easy, and in particular, the power supply by the non-contact method can be stably and safely supplied.

Referring again to FIG. 10, the unit support 180 supports the front wheel unit 160 and the rear wheel unit 170.

Between the unit support 180 and the front wheel unit 160, and between the unit support 180 and the rear wheel unit 170, the front wheel unit 160 and the rear wheel unit 170 with respect to the unit support 180. The front bearing 186 and the rear bearing 187 are respectively provided to connect the parts rotatably.

The buffer stopper 197 is connected to the unit support 180 to elastically buffer the collision of the mask supply bogie 120, as shown in Figs. 5, 6 and 8. That is, the buffer stopper 197 including the shaft and the spring plays a role of elastically buffering the amount of impact when the mask supply bogie 120 collides with a preceding bogie or collides with other equipment. A plurality of buffer stoppers 197 may be connected to the unit support 180.

1 and 2, the gripping unit 140 in the mask supply truck 120 is moved along the OHT rail 110 while gripping the mask M, And the operation of the gripping unit 140 can supply the mask M to the mask loading slot 3 of the mask loading port 2 as shown in FIG.

In this embodiment, since the mask supply truck 120 is provided with the wheel unit driver 190 having the differential synchronizer 193, the rotational speed between the inner wheels 161, 171 and the outer wheels 162, When the inner wheels 161 and 171 and the outer wheels 162 and 172 pass through the curved rail part 110b of the OHT rail 110, 110 can be smoothly driven. In particular, this structure has an advantage that the curved rail part 110b of the OHT rail 110 can smoothly run even if the mask supply carriage 120 is large or heavy.

Since the mask supply system of the present embodiment includes the wheel unit driver 190 having the differential sync driver 193, the mask supply system of the present embodiment can be manufactured easily and at a lower cost than the conventional one, The curved rail portion 110b of the OHT rail 110 can smoothly run, and the supply efficiency of the mask M can be increased.

As described above, according to the present embodiment, it is possible to easily manufacture with less cost than in the past, and even if the mask supply bogie is made larger or heavier, the curved rail portion of the OHT rail can run smoothly, .

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Accordingly, such modifications or variations are intended to fall within the scope of the appended claims.

1: chamber 110: OHT rail
110a: Straight rail part 110b: Curved rail part
115: rail hanger 120: mask supply truck
130: truck main body 140: gripping unit
141: Unit body 142: Gripper
143: gripper up / down driver 144: anti dropper
150: traveling module 160: front wheel unit
170: rear wheel unit 180: unit support
190: wheel unit driving unit 191: driving motor
192: drive shaft 193:
194: Side guide roller 195: Direction adjusting roller

Claims (14)

An OHT (Over Head Transfer) rail having a curved rail portion and disposed in an upper region of the chamber provided in a clean room; And
A traveling module coupled to the OHT rail to be capable of traveling, and including a mask supply cart for supplying a mask into the chamber,
The traveling module includes:
A wheel unit having an inner wheel traveling along an inner rail of the OHT rail and an outer wheel traveling along an outer rail of the OHT rail; And
And a differential gear portion for relatively adjusting a rotational speed between the inner wheel and the outer wheel, the wheel supply unit driving the wheel unit. The method of claim 1,
And a control unit for controlling the operation of the wheel unit driving unit when the mask supply cart travels on the curved rail unit of the OHT rail. The method of claim 1,
The control unit controls the operation of the differential locker provided in the wheel unit drive unit such that the speed of the outer wheel is faster than the speed of the inner wheel when the mask supply truck travels the curved rail portion of the OHT rail And the mask supply system. The method of claim 1,
The wheel unit driving unit,
A drive motor generating power for driving the mask supply cart; And
And a drive shaft which connects the inner wheel and the outer wheel to each other and is rotated by the drive motor and connected to the differential gear part. The method of claim 1,
The mask supply bogie,
And a balance body provided therein with a gripping unit for gripping a mask supplied into the chamber. The method of claim 5,
Wherein the gripping unit comprises:
A unit body;
A gripper connected to the unit body in an upper region in the bogie body and gripping or releasing the upper end of the mask while approaching or separating from each other;
A gripper up / down driver for driving the gripper up / down; And
And an anti dropper coupled to the unit body on the opposite side of the gripper and operative with the gripper to prevent the mask from dropping. The method of claim 1,
The wheel unit includes:
A front wheel unit that is driven along an inner rail of the OHT rail and a front outer wheel that runs along an outer rail of the OHT rail are provided on both sides; And
A rear inner wheel running along the inner rail of the OHT rail and a rear wheel unit provided on both sides of the rear outer wheel running along the outer rail of the OHT rail Characterized in that the mask supply system The method of claim 7, wherein
The traveling module includes:
A unit support for supporting the front wheel unit and the rear wheel unit;
A front bearing for rotatably connecting the front wheel unit and the unit support;
A rear bearing for rotatably connecting the rear wheel unit and the unit support; And
And a connector for connecting the unit support and the trolley body in a central region of the unit support. The method of claim 7, wherein
Wherein the front wheel unit and the rear wheel unit have the same structure. 10. The method of claim 9,
Wherein both the front wheel unit and the rear wheel unit comprise:
A side guide roller disposed at a lower position than the inner wheel and the outer wheel respectively provided on the front wheel unit and the rear wheel unit and guided by the side surface of the OHT rail to block the departure of the rail of the traveling module; And
Further comprising: an inner wheel provided in each of the front wheel unit and the rear wheel unit, and a direction adjusting roller provided at a higher position than the outer wheel. 10. The method of claim 9,
Wherein both the front wheel unit and the rear wheel unit comprise:
And a non-contact type power supply unit for supplying power to the driving motor by receiving the power in a non-contact type manner. The method of claim 7, wherein
The traveling module includes:
Further comprising a buffer stopper elastically buffering the collision of the mask supply bogie. The method of claim 1,
Further comprising a rail hanger for supporting the OHT rail. The method of claim 1,
The chamber is a deposition chamber for performing a deposition process of an organic light emitting display (OLED) through the mask,
Wherein an upper region of the deposition chamber is further provided with a mask loading port through which the mask supplied from the mask supply bogie is loaded.

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