SUBSTRATE HOLDING HAND AND SUBSTRATE CONVEYING ROBOT

A substrate holding hand includes a frame, a blade to support a substrate, a mounting member to support the blade and mount the blade to the frame, and an inclination adjusting mechanism operable to adjust an inclination of the blade with respect to a horizontal direction in a side view by adjusting an inclination of the mounting member with respect to the frame.

TECHNICAL FIELD

The present invention relates to a substrate holding hand and a substrate conveying robot, and relates to a substrate holding hand and a substrate conveying robot each including a blade to support a substrate.

BACKGROUND ART

Conventionally, a substrate holding hand including a blade to support a substrate is known. Such a hand is disclosed in Japanese Patent Laid-Open No. 2013-069914, for example.

Japanese Patent Laid-Open No. 2013-069914 discloses a substrate conveying hands (substrate holding hand) to convey substrates. These substrate conveying hands include hand main bodies (blades) that support the substrates. These substrate conveying hands support the substrates stored in a substrate storage container compatible with a SEMI (Semiconductor Equipment and Materials International) standard FOUP (Front Opening Unified Pod) by the hand main bodies and convey the substrates, for example.

Although not clearly described in Japanese Patent Laid-Open No. 2013-069914, in a conventional substrate storage container as described in Japanese Patent Laid-Open No. 2013-069914, substrates are stored such that they are parallel to a horizontal direction in a side view. In this case, in a conventional substrate conveying hand as described in Japanese Patent Laid-Open No. 2013-069914, hand main bodies are provided parallel to a horizontal direction in a side view so as to correspond to substrates stored in a substrate storage container.

PRIOR ART

Patent Document

SUMMARY OF THE INVENTION

Problems to be Solved by the Invention

In the conventional substrate conveying hand, it is difficult to adjust the inclinations of the hand main bodies (blades) that support the substrates with respect to the horizontal direction in the side view according to the inclinations of the substrates with respect to the horizontal direction when the substrates stored in the substrate storage container (storage container) are inclined with respect to the horizontal direction in the side view.

The present invention aims to provide a substrate holding hand and a substrate conveying robot each capable of easily adjusting the inclination of a blade that supports a substrate with respect to a horizontal direction in a side view according to the inclination of the substrate with respect to the horizontal direction even when the substrate stored in a storage container is inclined with respect to the horizontal direction in the side view.

Means for Solving the Problems

A substrate holding hand according to a first aspect of the present invention includes a frame, a blade to support a substrate, a mounting member to support the blade and mount the blade to the frame, and an inclination adjusting mechanism operable to adjust an inclination of the blade with respect to a horizontal direction in a side view by adjusting an inclination of the mounting member with respect to the frame.

A substrate conveying robot according to a second aspect of the present invention includes a substrate holding hand and an arm to move the substrate holding hand. The substrate holding hand includes a frame, a blade to support a substrate, a mounting member to support the blade and mount the blade to the frame, and an inclination adjusting mechanism operable to adjust an inclination of the blade with respect to a horizontal direction in a side view by adjusting an inclination of the mounting member with respect to the frame.

Effect of the Invention

According to the present invention, as described above, the inclination adjusting mechanism is provided to adjust the inclination of the blade with respect to the horizontal direction in the side view by adjusting the inclination of the mounting member with respect to the frame such that even when a substrate stored in the storage container (such as a hoop) is inclined with respect to the horizontal direction in the side view, the inclination of the blade that supports the substrate with respect to the horizontal direction in the side view can be easily adjusted according to the inclination of the substrate with respect to the horizontal direction. Furthermore, even when the substrate stored in the storage container is inclined with respect to the horizontal direction in the side view due to the inclination of the storage container itself, the inclination of the blade that supports the substrate with respect to the horizontal direction in the side view can be easily adjusted according to the inclination of the substrate with respect to the horizontal direction. Moreover, even when the blade bends due to the blade's own weight and the weight of the substrate held by the blade, for example, and is inclined with respect to the horizontal direction in the side view, the inclination of the blade that supports the substrate with respect to the horizontal direction in the side view can be easily adjusted according to the inclination of the substrate with respect to the horizontal direction.

MODES FOR CARRYING OUT THE INVENTION

An embodiment embodying the present invention is hereinafter described on the basis of the drawings.

The configuration of a substrate conveying robot100according to this embodiment is now described with reference toFIGS.1to5.

As shown inFIG.1, the substrate conveying robot100includes a substrate holding hand1and an arm2that moves the substrate holding hand1. As shown inFIGS.2to5, the substrate holding hand1includes a frame31, blades32that support substrates (semiconductor wafers) W, mounting members33that support the blades32and mount the blades32to the frame31, and inclination adjusting mechanisms34to adjust the inclinations of the blades32with respect to a horizontal direction in a side view by adjusting the inclinations of the mounting members33with respect to the frame31.

According to this embodiment, as described above, the inclination adjusting mechanisms34are provided to adjust the inclinations of the blades32with respect to the horizontal direction in the side view by adjusting the inclinations of the mounting members33with respect to the frame31such that even when the substrates W stored in a storage container (such as a hoop) are inclined with respect to the horizontal direction in the side view, the inclinations of the blades32that support the substrates W with respect to the horizontal direction in the side view can be easily adjusted according to the inclinations of the substrates W with respect to the horizontal direction. Furthermore, even when the substrates W stored in the storage container are inclined with respect to the horizontal direction in the side view due to the inclination of the storage container itself, the inclinations of the blades32that support the substrates W with respect to the horizontal direction in the side view can be easily adjusted according to the inclinations of the substrates W with respect to the horizontal direction. Moreover, even when the blades32bend due to the blades32′ own weights and the weights of the substrates W held by the blades32, for example, and are inclined with respect to the horizontal direction in the side view, the inclinations of the blades32that support the substrates W with respect to the horizontal direction in the side view can be easily adjusted according to the inclinations of the substrates W with respect to the horizontal direction.

The substrate holding hand1includes the frame31, the blades32, the mounting members33, and the inclination adjusting mechanisms34, as shown inFIGS.2to5.

As shown inFIGS.3to5, the inclination adjusting mechanisms34include inclination adjusting pins34a. The inclination adjusting pins34aare inserted into the mounting members33, support the mounting members33such that the mounting members33are rotatable about predetermined rotation axes C1extending in a lateral direction (X direction) perpendicular to a forward-rearward direction (Y direction) in which the frame31and the blades32are aligned in the horizontal direction, and extend in the lateral direction (X direction).FIG.5shows adjustment of the inclinations of the blades32in an exaggerated manner for easy understanding.

The mounting members33include a pair of mounting members33that mount a first side and a second side of a base end32cof each of the blades32to the frame31, respectively. The inclination adjusting pins34ainclude a pair of inclination adjusting pins34acorresponding to the pair of mounting members33. The inclination adjusting mechanisms34can adjust the inclinations of the blades32with respect to the horizontal direction in the side view by rotating the pair of mounting members33about the predetermined rotation axes C1with the pair of inclination adjusting pins34aas the center of rotation.

The inclination adjusting pins34aare supported by the frame31and protrude from the side of the frame31so as to be inserted into the mounting members33.

The inclination adjusting mechanisms34can adjust the inclinations of the blades32with respect to the horizontal direction in the side view by fastening and fixing the mounting members33to the frame31with fastening members35in a state in which the inclinations of the mounting members33have been adjusted by rotating the mounting members33about the predetermined rotation axes C1with the inclination adjusting pins34aas the center of rotation. The fastening members35extend parallel to the predetermined rotation axes C1, and are mounted laterally (in the X direction) to the frame31via the mounting members33.

The blades32include a plurality of (four) blades32that support the substrates W, respectively. The mounting members33support the plurality of blades32in common. The inclination adjusting mechanisms34can collectively adjust the inclinations of the plurality of blades32with respect to the horizontal direction in the side view by adjusting the inclinations of the mounting members with respect to the frame31.

The plurality of blades32are aligned at a predetermined pitch in a direction (Z direction) perpendicular to the main surfaces32aof the blades32. The inclination adjusting mechanisms34can collectively adjust the inclinations of the plurality of blades32with respect to the horizontal direction in the side view while maintaining the pitch between the plurality of blades32in the direction (Z direction) perpendicular to the main surfaces32aof the blades32.

The mounting members33are laterally attached to the side surfaces of the frame31.

As shown inFIG.1, the arm2is a horizontal articulated robot arm. The arm2includes a first arm2aand a second arm2b. The first arm2ais rotatable with respect to a base5, which is described below, with a first end as the center of rotation. Specifically, the first end of the first arm2ais rotatably connected to the base5via a first joint. The second arm2bis rotatable with respect to the first arm2awith a first end as the center of rotation. Specifically, the first end of the second arm2bis rotatably connected to a second end of the first arm2avia a second joint. The substrate holding hand1is rotatably connected to a second end of the second arm2bvia a third joint. A drive mechanism including a servomotor corresponding to a drive source for rotary drive, a rotational position sensor that detects the rotational position of an output shaft of the servomotor, and a power transmission mechanism that transmits the output of the servomotor to the joint is provided at each of the first joint, the second joint, and the third joint.

The substrate conveying robot100further includes the base5to which the arm2is attached, and an arm elevating mechanism6to which the base5is attached. A first end of the base5is connected to the first end of the first arm2a, and a second end of the base5is connected to the arm elevating mechanism6. The arm elevating mechanism6moves the arm2up and down by moving the base5up and down. The arm elevating mechanism6includes a servomotor corresponding to a drive source for up-down drive, a rotational position sensor that detects the rotational position of an output shaft of the servomotor, and a power transmission mechanism that transmits the output of the servomotor to the base5(arm2).

As shown inFIG.2, the substrate holding hand1includes the plurality of (four) blades32. That is, the substrate holding hand1can convey (hold) a plurality of (four) substrates W.

As shown inFIGS.2and3, the substrate holding hand1includes the frame31, the blades32, and the mounting members33. The frame31is a support that supports the blades32. The frame31includes a pair of side walls31aand a base end31bconnecting the pair of side walls31a. The pair of side walls31aare spaced apart from each other such that the wall surfaces thereof face each other in a direction (X direction) parallel to a direction in which a pair of front supports321are aligned. The pair of side walls31aextend in a direction (Y direction) perpendicular to the direction in which the pair of front supports321are aligned and parallel to the main surfaces32aof the blades32. The base end31bconnects base ends (portions on the Y2 direction side) of the pair of side walls31a. The base end31bhas a shape that is convexly curved toward the base end side (the Y2 direction side). The pair of side walls31aand the base end31bare provided in a U-shape, as viewed in the direction perpendicular to the main surfaces32aof the blades32.

The blades32are thin support plates that support the substrates W. Each of the blades32includes the front supports321on the tip end32bside (Y1 direction side) and rear supports322on the base end32cside (Y2 direction side). The blade32has a shape in which the tip end32bside is bifurcated. In the blade32, the pair of front supports321are distributed to the bifurcated portions. The pair of front supports321each have a plurality of (two) support surfaces at different heights. A pair of rear supports322each have a support surface at a height substantially the same as the heights of the lower (Z2 direction side) support surfaces of the pair of front supports321. The “height” refers to a distance from the main surfaces32aof the blades32in the direction (Z direction) perpendicular to the main surfaces32aof the blades32.

The pair of front supports321and the pair of rear supports322are provided on the main surface32aof each blade32. The support surfaces of the pair of front supports321and the pair of rear supports322support the rear surface (the surface on the Z2 direction side) of the outer peripheral edge of a substantially circular substrate W from below.

The mounting members33are laterally attached to the side walls31aof the frame31. Specifically, the mounting member33on the X1 direction side is attached to a tip end-side portion of the side wall31aon the X1 direction side of the frame31from the outer side (X1 direction side). The mounting member33on the X1 direction side is fixed to the tip end-side portion of the side wall31aon the X1 direction side of the frame31by the fastening member35on the X1 direction side. The mounting member33on the X2 direction side is attached to a tip end-side portion of the side wall31aon the X2 direction side of the frame31from the outer side (X2 direction side). The mounting member33on the X2 direction side is fixed to the tip end-side portion of the side wall31aon the X2 direction side of the frame31by the fastening member35on the X2 direction side. The fastening members35are inserted into the mounting members33in the X direction and fastened to fastening holes of the side walls31aof the frame31.

As shown inFIGS.4and5, the mounting members33each include plate-shaped supports33a,33b, and33cthat support the blades32. The supports33a,33b, and33care aligned in the direction (Z direction) perpendicular to the main surfaces31cof the blades32. The supports33a,33b, and33cextend from the frame31side (Y2 direction side) toward the tip ends32b(Y1 direction side) of the blades32. The support33asupports the upper (Z1 direction side) end blade (first stage blade)32on the upper surface side. The support33bsupports the intermediate blades (second stage and third stage blades)32in common. The support33bsupports the blades32on the upper surface side and the lower surface side, respectively. The support33csupports the lower (Z2 direction side) end blade (fourth stage blade)32on the lower surface side.

When the inclinations are adjusted by the inclination adjusting mechanisms34, the mounting members33are rotated about the rotation axes C1with the inclination adjusting pins34aas the center of rotation while the fastening members35are loosened. Thus, the plurality of blades32supported by the supports33a,33b, and33cof the mounting members33are rotated about the rotation axes C1while the pitch between the plurality of blades32is maintained. Consequently, the inclinations of the plurality of blades32with respect to the horizontal direction in the side view are collectively adjusted. Furthermore, the inclinations of the plurality of blades32with respect to the horizontal direction in the side view are fixed by tightening the fastening members35.

The substrate holding hand1further includes a movable support unit36that moves back and forth to support the substrates W, and a first movable pressing unit37and a second movable pressing unit38that move back and forth to press the substrates W. The movable support unit36includes pairs of support members36athat support the substrates W, and an air cylinder36bcorresponding to an actuator that moves the pairs of support members36aback and forth in the Y direction. In the movable support unit36, the pairs of support members36acan be moved forward in the Y1 direction by the air cylinder36bto be placed at support positions at which the pairs of support members36asupport the substrates W. Furthermore, in the movable support unit36, the pairs of support members36acan be moved backward in the Y2 direction by the air cylinder36bto be placed at retracted positions at which the pairs of support members36ado not support the substrates W. The pairs of support members36ahave support surfaces at heights substantially the same as the heights of the upper (Z1 direction side) support surfaces of pairs of front supports321. Each support surface of the pairs of support members36asupports the rear surface (the surface on the Z2 direction side) of the outer peripheral edge of the substantially circular substrate W from below.

The first movable pressing unit37includes a pair of pressing members37athat press the substrates W, and an air cylinder37bcorresponding to an actuator that moves the pair of pressing members37aback and forth in the Y direction. In the first movable pressing unit37, the pair of pressing members37acan be moved forward in the Y1 direction by the air cylinder37bto press the substrates W. Furthermore, in the first movable pressing unit37, the pair of pressing members37acan be moved backward in the Y2 direction by the air cylinder37bto be placed at retracted positions at which the pair of pressing members37ado not press the substrates W.

The second movable pressing unit38includes a pair of pressing members38athat press the substrates W, and an air cylinder38bcorresponding to an actuator that moves the pair of pressing members38aback and forth in the Y direction. In the second movable pressing unit38, the pair of pressing members38acan be moved forward in the Y1 direction by the air cylinder38bto press the substrates W. Furthermore, in the second movable pressing unit38, the pair of pressing members38acan be moved backward in the Y2 direction by the air cylinder38bto be placed at retracted positions at which the pair of pressing members38ado not press the substrates W.

In the substrate holding hand1, the upper (Z1 direction side) support surfaces of the pairs of front supports321and the support surfaces of the pairs of support members36aof the movable support unit36support the processed (washed) substrates W. The pair of pressing members37aof the first movable pressing unit37press the processed (washed) substrates W supported by the upper (Z1 direction side) support surfaces of the pairs of front supports321and the support surfaces of the pairs of support members36aof the movable support unit36.

In the substrate holding hand1, the lower (Z2 direction side) support surfaces of the pairs of front supports321and the support surfaces of pairs of rear supports322support the substrates W prior to processing (washing). The pair of pressing members38aof the second movable pressing unit38press the substrates W prior to processing (washing) supported by the lower (Z2 direction side) support surfaces of the pairs of front supports321and the support surfaces of the pairs of rear supports322. The pairs of front supports321, the pairs of rear supports322, the movable support unit36, the first movable pressing unit37, and the second movable pressing unit38are used properly for the substrates W prior to processing (washing) and the processed (washed) substrates W.

The air cylinder36bof the movable support unit36, the air cylinder37bof the first movable pressing unit37, and the air cylinder38bof the second movable pressing unit38are arranged as a frame inner component40aon the inside of the frame31. The air cylinder36bof the movable support unit36, the air cylinder37bof the first movable pressing unit37, and the air cylinder38bof the second movable pressing unit38are aligned in the direction (Z direction) perpendicular to the main surfaces32aof the blades32on the inside of the frame31. Specifically, the air cylinder36bof the movable support unit36, the air cylinder37bof the first movable pressing unit37, and the air cylinder38bof the second movable pressing unit38overlap each other, as viewed in the direction (Z direction) perpendicular to the main surfaces32aof the blades32. Therefore, the air cylinders36b,37b, and38bare not aligned in the width direction (X direction) of the frame31, and thus the air cylinders36b,37b, and38bcan be compactly arranged in the width direction (X direction) of the frame31.

The substrate holding hand1further includes a cover (casing)39(seeFIG.2) separately from the frame31. The cover39covers the frame31and portions (portions arranged on the inside of the frame31) of the movable support unit36, the first movable pressing unit37, and the second movable pressing unit38.

Advantages of this Embodiment

According to this embodiment, the following advantages are achieved.

According to this embodiment, as described above, the inclination adjusting mechanisms34are provided to adjust the inclinations of the blades32with respect to the horizontal direction in the side view by adjusting the inclinations of the mounting members33with respect to the frame31such that even when the substrates W stored in the storage container (such as a hoop) are inclined with respect to the horizontal direction in the side view, the inclinations of the blades32that support the substrates W with respect to the horizontal direction in the side view can be easily adjusted according to the inclinations of the substrates W with respect to the horizontal direction. Furthermore, even when the substrates W stored in the storage container are inclined with respect to the horizontal direction in the side view due to the inclination of the storage container itself, the inclinations of the blades32that support the substrates W with respect to the horizontal direction in the side view can be easily adjusted according to the inclinations of the substrates W with respect to the horizontal direction. Moreover, even when the blades32bend due to the blades32′ own weights and the weights of the substrates W held by the blades32, for example, and are inclined with respect to the horizontal direction in the side view, the inclinations of the blades32that support the substrates W with respect to the horizontal direction in the side view can be easily adjusted according to the inclinations of the substrates W with respect to the horizontal direction.

According to this embodiment, as described above, the inclination adjusting mechanisms34include the inclination adjusting pins34a. The inclination adjusting pins34aare inserted into the mounting members33, support the mounting members33such that the mounting members33are rotatable about the predetermined rotation axes C1extending in the lateral direction perpendicular to the forward-rearward direction in which the frame31and the blades32are aligned in the horizontal direction, and extend in the lateral direction. Accordingly, the mounting members33can be easily and reliably rotated about the predetermined rotation axes C1extending in the lateral direction with the inclination adjusting pins34aas the center of rotation, and thus the inclinations of the blades22with respect to the horizontal direction in the side view can be easily and reliably adjusted by the inclination adjusting mechanisms34including the inclination adjusting pins34a.

According to this embodiment, as described above, the mounting members33include the pair of mounting members33to mount the first side and the second side of the base end32cof each of the blades32to the frame31, respectively. The inclination adjusting pins34ainclude the pair of inclination adjusting pins34acorresponding to the pair of mounting members33. The inclination adjusting mechanisms34are operable to adjust the inclinations of the blades32with respect to the horizontal direction in the side view by rotating the pair of mounting members33about the predetermined rotation axes C1extending in the lateral direction with the pair of inclination adjusting pins34aas the center of rotation. Accordingly, the pair of mounting members33can be more easily and reliably rotated about the predetermined rotation axes C1using the pair of inclination adjusting pins34a, and thus the inclinations of the blades22with respect to the horizontal direction in the side view can be more easily and reliably adjusted by the inclination adjusting mechanisms34including the pair of inclination adjusting pins34a.

According to this embodiment, as described above, the inclination adjusting pins34aare supported by the frame31and protrude from the side of the frame31so as to be inserted into the mounting members33. Accordingly, the mounting members33can be rotated about the predetermined rotation axes C1by the inclination adjusting pins34afirmly supported by the frame31. Consequently, the inclinations of the blades32with respect to the horizontal direction in the side view can be easily adjusted.

According to this embodiment, as described above, the inclination adjusting mechanisms34are operable to adjust the inclinations of the blades32with respect to the horizontal direction in the side view by fastening and fixing the mounting members33to the frame31with the fastening members35in a state in which the inclinations of the mounting members33have been adjusted by rotating the mounting members33about the predetermined rotation axes C1with the inclination adjusting pins34aas the center of rotation. Accordingly, the inclinations of the blades32with respect to the horizontal direction in the side view can be fixed to adjusted inclinations only by fastening and fixing the mounting members33to the frame31with the fastening members35, and thus the inclinations of the blades32with respect to the horizontal direction in the side view can be easily adjusted.

According to this embodiment, as described above, the blades32include the plurality of blades32to support the substrates W, respectively. The mounting members33support the plurality of blades32in common. The inclination adjusting mechanisms34are operable to collectively adjust the inclinations of the plurality of blades32with respect to the horizontal direction in the side view by adjusting the inclinations of the mounting members33with respect to the frame31. Accordingly, as compared with a case in which it is necessary to individually adjust the inclinations of the plurality of blades32with respect to the horizontal direction in the side view, it is possible to save time and effort in adjusting the inclinations of the plurality of blades32with respect to the horizontal direction in the side view, and thus the inclinations of the plurality of blades32with respect to the horizontal direction in the side view can be easily adjusted.

According to this embodiment, as described above, the plurality of blades32are aligned at the predetermined pitch in the direction perpendicular to the main surfaces32aof the blades32. The inclination adjusting mechanisms34are operable to collectively adjust the inclinations of the plurality of blades32with respect to the horizontal direction in the side view while maintaining the pitch between the plurality of blades32in the direction perpendicular to the main surfaces32aof the blades32. Accordingly, it is not necessary to adjust the pitch between the plurality of blades32(a distance between the centers of the blades32) after the inclinations of the plurality of blades32with respect to the horizontal direction in the side view are adjusted, and thus the inclinations of the blades32with respect to the horizontal direction in the side view can be more easily adjusted.

According to this embodiment, as described above, the mounting members33are laterally attached to the side surface of the frame31. Accordingly, as compared with a case in which the mounting members33are attached to the frame31from above or below, the inclinations of the mounting members33with respect to the horizontal direction in the side view can be easily adjusted from the side, and thus adjustment of the inclinations of the blades32with respect to the horizontal direction in the side view by adjustment of the inclinations of the mounting members33can be easily performed.

MODIFIED EXAMPLES

For example, while the example in which the arm is a horizontal articulated robot arm has been shown in the aforementioned embodiment, the present invention is not limited to this. For example, the arm may be an arm other than a horizontal articulated robot arm, such as a vertical articulated robot arm.

While the example in which the substrate holding hand includes a plurality of blades has been shown in the aforementioned embodiment, the present invention is not limited to this. For example, the substrate holding hand may include one blade.

While the example in which the substrate holding hand includes four blades has been shown in the aforementioned embodiment, the present invention is not limited to this. For example, the substrate holding hand may include a plurality of blades other than four.

While the example in which each of the blades has a bifurcated shape has been shown in the aforementioned embodiment, the present invention is not limited to this. For example, each of the blades may have a shape other than a bifurcated shape.

While the example in which each of the blades can support two substrates at different heights has been shown in the aforementioned embodiment, the present invention is not limited to this. For example, each of the blades may be able to support only one substrate (able to support a substrate at only one height).

While the example in which the movable support unit is provided has been shown in the aforementioned embodiment, the present invention is not limited to this. For example, the movable support unit may not be provided.

While the example in which the movable support unit includes a pair of support members for one substrate has been shown in the aforementioned embodiment, the present invention is not limited to this. For example, the movable support unit may include one support member for one substrate.

While the example in which two pressing units, which are the first movable pressing unit and the second movable pressing unit, are provided has been shown in the aforementioned embodiment, the present invention is not limited to this. For example, only one movable pressing unit may be provided.

While the example in which each of the movable pressing units includes a pair of pressing members has been shown in the aforementioned embodiment, the present invention is not limited to this. For example, each of the movable pressing units may include one pressing member.

While the example in which the inclination adjusting mechanisms include the inclination adjusting pins has been shown in the aforementioned embodiment, the present invention is not limited to this. For example, the inclination adjusting mechanisms may include inclination adjusting structures such as inclination adjusting screws other than the inclination adjusting pins.

While the example in which the inclination adjusting mechanisms can collectively adjust the inclinations of the plurality of blades with respect to the horizontal direction in the side view has been shown in the aforementioned embodiment, the present invention is not limited to this. In the present invention, the inclination adjusting mechanisms may be able to individually adjust the inclinations of the plurality of blades with respect to the horizontal direction in the side view. Alternatively, the inclination adjusting mechanisms may be able to collectively adjust the inclinations of some of the plurality of blades with respect to the horizontal direction in the side view.

DESCRIPTION OF REFERENCE NUMERALS