TECHNICAL FIELD
[1]
The present disclosure relates to a solar panel unit including a solar panel and an actuator unit for driving the solar panel.
BACKGROUND ART
[2]
Conventionally, a solar panel unit including a solar panel and an actuator unit for driving the solar panel has been known. Driving the actuator unit of this solar panel unit such that a light-receiving surface of the solar panel tracks the movement of the sun increases the amount of sunlight that the solar panel receives and results in an increase in power generated by the solar panel. For example, Patent Document 1 discloses a solar panel unit of this type. The solar panel unit of Patent Document 1 includes a heat-receiving tank constituted by a sealed container filled with a hydraulic fluid and an actuator unit activated by a pressure of the hydraulic fluid expanding in the heat-receiving tank due to reception of radiant heat of sunlight. The actuator unit includes a piston of which an end is fixed to a solar panel, and the pressure applied by the hydraulic fluid causes the piston to reciprocate, thereby driving the solar panel.
CITATION LIST PATENT DOCUMENT
[3]
PATENT DOCUMENT 1: Japanese Patent Publication No. H06-301420 JPH06301420B
SUMMARY OF THE INVENTION TECHNICAL PROBLEM
[4]
Meanwhile, an actuator unit for driving a solar panel unit is installed on a roof of a house or a factory, for example. If the actuator unit is considerably heavy, large loads are imposed on the roof. It is accordingly required to improve the load-bearing capacity of the roof in accordance with the imposed loads. In addition, installation of such a heavy actuator unit is difficult.
[5]
It is therefore an object of the present disclosure to reduce the weight of an actuator unit configured to drive a solar panel.
SOLUTION TO THE PROBLEM
[6]
A first aspect of the present disclosure relates to a solar panel unit including at least one solar panel (92a), at least one support member (94) configured to support the solar panel (92a) through at least one rotation shaft (95), and an actuator unit (100) including at least one air bag (101, 102) capable of extending and contracting according to an internal pressure, and configured to rotate the solar panel (92a) around an axis of the rotation shaft (95) according to extension and contraction of the air bag (101, 102).
[7]
In the first aspect, the solar panel (92a) is supported by the support member (94) through the rotation shaft (95). The solar panel (92a) is caused to rotate around the axis of the rotational shaft (95) by causing the air bag (101, 102) to extend or contract in accordance with the internal pressure.
[8]
A second aspect of the present disclosure is the solar panel of the first aspect wherein the air bag (101, 102) includes an opening (101c, 102c) through which a space inside the air bag (101, 102) communicates with a space outside the air bag (101, 102), a reception portion (101b, 102b) supporting a back surface of the solar panel (92a), and a body (101a, 102a) configured to extend by means of compressed air so as to move the reception portion (101b, 102b) toward the solar panel (92a), and the actuator unit (100) includes an air supply/exhaust mechanism (105) configured to perform, in a switchable manner, a first operation in which compressed air is supplied to the space inside the air bag (101, 102) through the opening (101c, 102c) and a second operation in which air in the air bag (101, 102) is exhausted to the outside of the air bag (101, 102) through the opening (101c, 102c).
[9]
According to the second aspect, when the air supply/exhaust mechanism (105) performs the first operation, compressed air is supplied to the space inside the air bags (101, 102) through the opening (101c, 102c). Consequently, the body (101a, 102a) of the air bag (101, 102) extends to cause the reception portion (101b, 102b) to move toward the solar panel (92a). The reception portion (101b, 102b) pushes the back surface of the solar panel (92a) upward to cause the solar panel (92a) to rotate in a direction in which the air bag (101, 102) extends. On the other hand, when the air supply/exhaust mechanism (105) performs the second operation, air in the air bag (101, 102) is exhausted to the outside through the opening (101a, 102c). Consequently, loads of the solar panel (92a) act downwardly on the air bag (101, 102) whose internal pressure has decreased, thereby causing the air bag (101, 102) to contract. As the result, the solar panel (92a) rotates in a direction in which the reception portion (101b, 102b) of the air bag (101, 102) contracts.
[10]
A third aspect of the present disclosure is the solar panel unit of the second aspect wherein the actuator unit (100) includes the two air bags (101, 102) disposed such that the rotation shaft (95) is located between the air bags (101, 102).
[11]
In the third aspect, the two air bags (101, 102) disposed such that the rotation shaft (95) is located between the air bags (101, 102) are employed as the actuator unit (100). With this configuration, the solar panel (92a) can be rotated in a predetermined direction (a first direction) by causing the air bag (101), which is one of the two air bags (101, 102), to push the solar panel (92a) upward whereas the solar panel (92a) can be rotated in a second direction opposite to the first direction by causing the other air bag (102) to push the solar panel (92a) upward. In this manner, it is ensured that the solar panel (92a) rotates in both opposite directions.
[12]
A fourth aspect of the present disclosure is the solar panel unit of the second aspect, wherein the actuator unit (100) includes the air bag (101) as a single air bag, and an elastic member (99a, 99b) causing an urging force to act on the solar panel (92a), in such a manner that the urging force acts in a direction opposite to a direction in which the solar panel rotates when the air bag (101) extends.
[13]
According to the fourth aspect, the air bag (101) provided as a single air bag and the elastic member (99a, 99b) causing the urging force to act on the solar panel (92a) in the direction opposite to the direction in which the solar panel rotates when the air bag (101) extends are employed as the actuator unit (100). With this configuration, the solar panel (92a) can be rotated in a predetermined direction (a first direction) by causing the air bag (101) to push the solar panel (92a) upward whereas the solar panel (92a) can be rotated in a second direction opposite to the first direction by causing the elastic member to urge the solar panel (92a). In this manner, it is ensured that the solar panel (92a) rotates in both opposite directions.
[14]
A fifth aspect of the present disclosure is the solar panel of the fourth aspect wherein the actuator unit (100) includes a lock mechanism (170) configured to control rotation of the solar panel (92a) urged by the elastic member (99a, 99b) to retain the solar panel (92a) at a predetermined rotati…
