JPH0634198U - Blower or compressor - Google Patents

Abstract

(57) [Summary] [Purpose] To eliminate the inlet guide vanes in a centrifugal blower or centrifugal compressor and to impart swirl to the impeller inlet flow. [Composition] By utilizing the pressure difference between the both sides of the flow guide (10), that is, the inside of the scroll (16) and the impeller inlet (17), an opening (11) is opened in the flow guide (10) and it is inclined tangentially. The nozzle ring (12) having the nozzle flow channel (13) is provided outside the opening (11), and the gas in the scroll (16) is swirled to make the impeller inlet (1
Lead to 7). The swirl strength is adjusted by rotating the nozzle ring (12).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is applied to a centrifugal blower or a centrifugal compressor.

[0002]

[Prior art]

 FIG. 3 is a vertical sectional view showing an example of a conventional centrifugal blower. Conventionally, an inlet guide vane (21) is provided inside the flow guide (20), and by changing the mounting angle of the inlet guide vane, a pre-swirl is given to the flow sucked into the impeller (22), so that the blower or the compressor is compressed. The flow rate and pressure of the machine were adjusted.

[0003]

[Problems to be solved by the device]

 The conventional centrifugal blower and the like have the following problems to be solved. When the flow passes through the inlet guide vanes (21), pressure loss occurs, and efficiency is reduced by at least 1 to 2% as compared with the case without the inlet guide vanes (21). The inlet guide vane (21) has a vane (23), a boss (24), and a link mechanism (25) and has a large weight. Especially, in the case of a double-suction type centrifugal fan, these are installed inside both bearings. Since the shaft length becomes longer due to the provision, not only the rotating part consisting of the impeller and the shaft becomes heavier, but also the weight of the supporting structure becomes heavier, and the total weight of the centrifugal fan increases.

[0004]

[Means for Solving the Problems]

 In order to solve the above-mentioned conventional problems, the present invention provides a centrifugal blower or compressor having an impeller, a scroll and a flow guide, wherein the flow guide has a plurality of openings at equal intervals along the circumferential direction. A hole is opened, and a nozzle ring that can rotate in the circumferential direction along the wall surface of the flow guide is provided outside the opening, and the nozzle ring has the same number of nozzle channels as the openings in the circumferential direction. The present invention proposes a blower or a compressor characterized in that the nozzle channels are opened at equal intervals and the direction of the nozzle flow channel is inclined with respect to the plane including the rotation axis of the impeller.

[0005]

[Action]

 In the present invention, since there is no structure in the suction flow, loss can be prevented. In particular, in the case of a double suction centrifugal blower having an inlet guide vane, there are less restrictions on the bearing position and the weight can be reduced.

[0006]

【Example】

 1 is a vertical sectional view showing an embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II of FIG. In this embodiment, the flow guide (10) is provided with a plurality of apertures (11) at equal intervals along the circumferential direction, and can be rotated in the circumferential direction along the wall surface of the flow guide (10) outside thereof. A nozzle ring (12) is provided. The nozzle ring (12) is provided with the same number of nozzle channels (13) and nozzle walls (14) as the openings (11). The directions of the nozzle channels (13) are inclined with respect to the plane including the rotation axis of the impeller (22). Since the inside of the nozzle wall (14) is in contact with the flow guide (10), the nozzle ring (12) is rotated to move the nozzle channel (13) to the flow guide as shown in FIG. 2 (b). When it is superposed on the opening (11), the flow (15) from the inside of the scroll (16) to the inlet (17) of the impeller (22) is generated. Then, since the direction of the nozzle flow path (13) is inclined with respect to the plane including the rotation axis, a swirl flow can be given to the flow at the inlet (17) of the impeller (22). When the nozzle wall (14) is overlapped with the opening (11) of the flow guide as shown in FIG. 2 (a), the opening is closed. Further, since the nozzle flow path (13) has an inclination in the axial direction as shown in FIG. 1, it is possible to generate a flow toward the impeller (22) while turning.

As a pre-swirling generator that replaces the conventional inlet guide vane (21), air or gas from the discharge pressure of a blower or compressor or another pressure source is jetted in the circumferential direction of the flow guide to impeller inlet. The idea of causing a pre-swirl in the flow of air has been conventionally considered, but in this embodiment, the suction flow inside the flow guide is used by utilizing the differential pressure between the scroll of the centrifugal blower or the centrifugal compressor and the flow guide. It has a structure that gives a pre-turning to the.

[0008]

[Effect of device]

 According to the present invention, a pre-swirl can be given to the suction flow of a centrifugal blower or a centrifugal compressor without using an inlet guide vane. The strength of the pre-swirl flow can be adjusted by adjusting the area of the opening.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a vertical cross-sectional view showing an example of a conventional centrifugal blower.

[Explanation of symbols]

 (10) Flow guide (11) Open hole (12) Nozzle ring (13) Nozzle flow path (14) Nozzle wall (16) Scroll (22) Impeller

Claims (1)

[Scope of utility model registration request] 1. A centrifugal blower or compressor provided with an impeller, a scroll and a flow guide, wherein the flow guide is provided with a plurality of holes at equal intervals along the circumferential direction. A nozzle ring that can be rotated in the circumferential direction along the wall surface of the flow guide is provided on the outside, and the same number of nozzle channels as the openings are opened in the nozzle ring at equal intervals along the circumferential direction. The blower or compressor is characterized in that the direction of the nozzle flow path is inclined with respect to a plane including the rotation axis of the impeller.