TECHNICAL FIELD

The present invention relates to a package-type compressor.

BACKGROUND ART

Patent Document 1 discloses a package-type compressor having a casing accommodating a body unit, an oil separator, a controller, a heat exchanger, a cooling fan device, etc. The compressor will be described in detail.

The body unit has a compressor body compressing air and a motor driving this compressor body, with the compressor body and the motor being integrated. More specifically, the compressor body and the motor are vertically installed such that the rotation shaft of the compressor body and the drive shaft of the motor extend in the vertical direction, with the motor being connected to the upper side of the compressor body.

At the lower portion of the right-hand side surface of the casing, there is formed an air suction port, and there are provided a first duct adjacent to a portion of the air suction port and a second duct adjacent to another portion of the air suction port. At the left-hand side surface side of the casing, there is provided a third duct extending in the vertical direction. The heat exchanger is provided at the lower portion of the third duct, and the cooling fan device is provided at the upper portion of the third duct. An air discharge port is formed in the upper surface of the casing.

The cooling fan device is equipped with a case having a suction port and a delivery port, a cooling fan (centrifugal fan) accommodated in the case, and a fan motor driving the cooling fan. The cooling fan and the fan motor are arranged such that their rotation shafts extend in the horizontal direction. The suction port of the case is connected to the third duct, and the delivery port of the case is connected to the air discharge port. The cooling fan device induces a flow of the cooling air inside the casing (more specifically, a flow of the cooling air sucked in through the air suction port and discharged through the air discharge port).

The first duct guides the cooling air from the air suction port to the motor of the body unit to cool the motor. The second duct causes the cooling air from the air suction port to flow along the controller to cool the controller. The cooling air having cooled the motor and the controller cools the heat exchanger. After this, the cooling air heads for the cooling fan device via the third duct.

PRIOR ART DOCUMENT

Patent Document

Patent Document 1: JP-1994-346875-A

SUMMARY OF THE INVENTION

Problem to be Solved by the Invention

In the prior-art technique disclosed in Patent Document 1, the compressor body and the motor of the body unit are vertically installed, with the compressor body and the motor being connected together in the vertical direction so as to be integrated with each other. As a result, it is possible to achieve a reduction in the installation area of the body unit and, by extension, a reduction in the installation area of the package-type compressor. Further, although not described in Patent Document 1, when the cooling air is caused to flow in the vertical direction along the body unit, it is possible to efficiently cool the body unit.

In the prior-art technique described in Patent Document 1, however, the air suction port is formed solely in one side surface of the casing, and there are limitations to the size of the air suction port due to a restriction such as sound insulation. Further, the flow path of the cooling air, which extends from the air suction port via the first or second duct and further extends to the air discharge port via the third duct, is relatively long, and the pressure loss of the cooling air flow path is relatively large. Thus, it is difficult to increase the flow rate of the cooling air cooling the body unit and the flow rate of the cooling air cooling the controller. Further, it is difficult to balance the flow rate of the cooling air in the first duct and that in the second duct, and it is difficult to increase the flow rate of the cooling air of the second duct (i.e., the flow rate of the cooling air cooling the controller). Thus, there is room for an improvement in terms of the cooling performance for cooling the body unit and the controller.

The present invention has been made in view of the above problem. It is an object of the present invention to achieve an improvement in terms of the cooling performance for cooling the body unit and the controller.

Means for Solving the Problem

To achieve the above object, the structure as claimed in the appending claims is applied. The present invention includes a plurality of means for solving the above problem, an example of which is a package-type compressor including: a body unit which has a compressor body compressing a gas and a motor driving the compressor body and in which the compressor body and the motor are vertically connected to be integrated while vertically installing the compressor body and the motor such that a rotation shaft of the compressor body and a drive shaft of the motor extend vertically; a controller controlling the motor; a casing accommodating the body unit and the controller at a lower portion thereof; a first cooling air inlet formed in one side surface of the casing; a second cooling air inlet formed in another side surface of the casing; a cooling air outlet formed in an upper surface of the casing; a fan duct provided at an upper portion of the casing and having a suction port at a lower surface and a delivery port at an upper surface; a cooling fan accommodated in the fan duct and arranged such that a rotation shaft extends in a vertical direction, the cooling fan inducing a flow of cooling air taken in through the first and second cooling air inlets and discharged through the cooling air outlet; an air cooling type heat exchanger arranged above the delivery port of the fan duct and below the cooling air outlet; a machine chamber that is provided below the fan duct and accommodates the body unit and that causes the cooling air taken in at the first cooling air inlet to flow along the body unit and to head for the suction port of the fan duct; and a cooling duct that is provided below the fan duct and that causes the cooling air taken in at the second cooling air inlet to flow along the controller and to head for the suction port of the fan duct, wherein a center position of the suction port of the fan duct is offset away from the first cooling air inlet and toward the second cooling air inlet with respect to a center position of the drive shaft of the motor.

Effect of the Invention

In accordance with the present invention, it is possible to achieve an improvement in terms of the cooling performance for cooling the body unit and the controller.

Other objects, structure, and effects of the present invention will become apparent from the following description.

