CENTRIFUGAL BLOWER

Abstract

Centrifugal blower (1) has casing (2) having scroll (6) and impeller (3) incorporated in casing (2). Casing (2) has side plate (5) with suction opening (4) and motor-fixing side plate (8) on which motor (7) is mounted. Impeller (3) is fixed to motor (7). Each of side plate (5) and motor-fixing side plate (8) has an outer shape of a rectangle with four corners (20) cut off.

Description

TECHNICAL FIELD

The present invention relates to centrifugal blowers.

BACKGROUND ART

The description below shows a structure of a conventional centrifugal blower incorporated in ventilation blowers, such as a duct fan, and in air conditioners. The centrifugal blower is formed as a self-standing structure held by a fan casing alone, and is incorporated in an air conditioner and the like. The fan casing has a rectangular side plate with a flange formed on the four sides of the plate. The flange is formed such that each edge of the four sides is bent and raised from each side of the side plate. The structure increases the strength of the side plate, allowing the centrifugal blower to be fixed as a self-standing structure. Such structured centrifugal blower is directly fixed to an air conditioner and the like.

Hereinafter, the structure will be described with reference to FIG. 4 showing a perspective view of a conventional centrifugal blower (see Patent literature 1, for example). As shown in FIG. 4, centrifugal blower 101 is formed of casing 102 and impeller 103 built in casing 102. Casing 102 is formed of side plate 105 having suction opening 104, scroll 106, and motor-fixing side plate 108 on which motor 107 is mounted. Impeller 103 is fixed to motor 107.

When motor 107 drives impeller 103 to rotate, suction air 109 flows through suction opening 104 into casing 102 via impeller 103. The air then blows out of impeller 103 and is pressurized in casing 102. Having been converted from dynamic pressure to static pressure, the air flows out of discharge opening 110 as discharge air 111.

Centrifugal blower 101 is designed as a self-standing structure held by casing 102 alone. For the purpose above, each of side plate 105 and motor-fixing side plate 108 is formed into a rectangle with flange 112 disposed on its four sides. Flange 112 works as a reinforcement rib, which protects side plate 105 and motor-fixing side plate 108 from a warp or deformation in the direction of the plate surfaces and enhances the strength of them. With the structure above, centrifugal blower 101 can be used as a self-standing structure held by casing 102 alone. Such structured centrifugal blower 101 is directly fixed to an air conditioner and the like.

CITATION LIST

Patent Literature

PTL 1: Japanese Unexamined Utility Model Application Publication No. 62-133998

SUMMARY OF THE INVENTION

FIG. 5 is a top view of a conventional centrifugal blower in a packed state, i.e., shows centrifugal blower 101 in a packed state seen from above. According to centrifugal blower 101, as shown in FIG. 4 and FIG. 5, the own weight of motor 107 is commonly supported by motor-fixing side plate 108. In packing, suction opening 104 of the centrifugal blower is faced to bottom 114 of container box 113 so that the motor's own weight applied to motor-fixing side plate 108 is supported by the entire structure of casing 102.

Centrifugal blower 101 has a shape of a cuboid or cube having corners 115. If blower 101 packaged in the box is accidentally dropped, corners 115 can be damaged by the impact of the drop. To protect corners 115 from the drop impact, buffering area 116 has to be formed between container box 113 and the body of centrifugal blower 101. The need for buffering area 116 has brought a problem—increase in packaging volume.

The centrifugal blower of the present invention contains a casing having a scroll and an impeller incorporated in the casing. The casing has a side plate with a suction opening and a motor-fixing side plate on which the motor is mounted. The impeller is fixed to the motor. Each of the side plate and the motor-fixing side plate has an outer shape of a rectangle with the four corners cut off.

When such formed centrifugal blower is packed in a container box whose bottom has a size approximately the same as the external dimensions of the centrifugal blower, a space is kept between a cut-off part and the container box. That is, the structure eliminates the corners that are easily damaged if the centrifugal blower packaged in the box is accidentally dropped. By virtue of the structure with no need of buffering material at the corners in packing, the package volume will not increase.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of a centrifugal blower of an exemplary embodiment of the present invention.

FIG. 2 is a sheet-metal development view of a motor-fixing side plate of the centrifugal blower.

FIG. 3 is a top view of the centrifugal blower in a packed state.

FIG. 4 is a perspective view of a conventional centrifugal blower.

FIG. 5 is a top view of the centrifugal blower in a packed state.

DESCRIPTION OF EMBODIMENT

Hereinafter, an exemplary embodiment of the present invention will be described with reference to the accompanying drawings.

Exemplary Embodiment

FIG. 1 is a perspective view of a centrifugal blower of the exemplary embodiment of the present invention. As shown in FIG. 1, centrifugal blower 1 has casing 2 and impeller 3 built in casing 2. Casing 2 has side plate 5 having suction opening 4, scroll 6, and motor-fixing side plate 8 on which motor 7 is mounted.

Impeller 3 is fixed to the rotation shaft of motor 7. The rotation of impeller 3 driven by motor 7 allows suction air 9 to flow into casing 2 from suction opening 4 via impeller 3. The air then blows out of impeller 3 and is pressurized in casing 2. Having conversion from dynamic pressure to static pressure, the air flows out of discharge opening 10 as discharge air 11.

Each of side plate 5 and motor-fixing side plate 8 has an outer shape, as an anterior view facing suction opening 4, of a rectangular whose four corners 20 cut off. Side plate 5 and motor-fixing side plate 8 should preferably be disposed such that long sides 12 and short sides 13 of side plate 5 are parallel to those of motor-fixing side plate 8. Further preferably, long sides 12 and short sides 13 of side plate 5 should be the same as long sides 12 and short sides 13, respectively, of motor-fixing side plate 8. Side plate 5 and motor-fixing side plate 8 have an outer shape of octagon. Besides, each of side plate 5 and motor-fixing side plate 8 has flange 14 standing upright like a wall on the periphery of the plate.

FIG. 2 is a sheet-metal development view of the motor-fixing side plate of the centrifugal blower; specifically, it is a sheet-metal development view of motor-fixing side plate 8 with flange 14 not yet formed. Bend section 15 of FIG. 2 is a line connecting between adjacent edges 20a of four corners 20 of motor-fixing side plate 8. Similarly, bend section 15 of side plate 5 shown in FIG. 1 is a line connecting between adjacent edges 20a of four corners 20. Flange 14 is formed parallel to bend section 15 in a manner that each side of the plates is outwardly bent at bend section 15.

Bend section 15 is formed on each long side 12. Bend section 15 has extended sections 16 extended along each long side 12 on the side of short side 13. That is, flange 14 has extended sections 16 extended from the both ends of bend section 15. Flange 14 at short side 13 is so formed that each of extended sections 16 is bent at bend line 15a and then adjacent two extended sections 16 are overlapped with each other. Flange 14 on short side 13 shown in FIG. 1 is thus completed. Four corners 20 are cut off in the same shape, which allows flange 14 to be easily formed.

The workings and effect of the aforementioned structure will be described below. FIG. 3 is a top view of the centrifugal blower in a packed state of the exemplary embodiment. Specifically, FIG. 3 shows container box 18, seen from above, in which centrifugal blower 1 is packed. Centrifugal blower 1 is packed in container box 18 in a manner that motor-fixing side plate 8 places above. Container box 18 has bottom 17 that is approximately the same as the outside dimension of side plate 5 of centrifugal blower 1 shown in FIG. 1; specifically, bottom 17 is a little bit larger than the rectangle formed by long sides 12 of side plate 5.

When centrifugal blower 1 is packed in the box, space 19 is retained between container box 18 and the cut-off of side plate 5 and motor-fixing side plate 8. When a device in a packed state is dropped down, the most vulnerable part is an angulated section of the device. As shown in FIG. 3, centrifugal blower 1 has no angulated section and space 19 is formed instead. Space 19 is a buffer against an accidental drop of centrifugal blower 1 in a packed state, working as impact absorption. Container box 18 absorbs the drop impact while deforming, protecting centrifugal blower 1 from damage.

As shown in FIG. 1, long sides 12 of side plate 5 and motor-fixing side plate 8 should preferably be the same in size and be disposed in parallel; similarly, short sides 13 of the two plates should preferably be the same in size and be disposed in parallel. Further preferably, the four sides of container box 18 of FIG. 3 in which centrifugal blower 1 is packed should be the same in size. The structure eliminates limitation on packing positioning centrifugal blower 1 (i.e., eliminates wrong orientation of centrifugal blower 1 in packing), making space 19 for sure.

Although side plate 5 and motor-fixing side plate 8 of the embodiment in FIG. 1 have an outer shape of octagon, the octagonal shape may have rounded-off corners. That is, side plate 5 and motor-fixing side plate 8 may be substantially shaped into an octagon with the corners rounded off. The structure—even when side plate 5 and motor-fixing side plate 8 are substantially shaped into an octagon—protects centrifugal blower 1 in a packed state from drop impact.

In the embodiment, each of side plate 5 and motor-fixing side plate 8 shown in FIG. 1 has eight sides of two pairs of long sides 12 facing each other and two pairs of short sides 13 facing each other, but it is not limited to; each plate may contain more sides, as long as having at least eight.

In the embodiment, flange 14 at each short side 13 of side plate 5 and motor-fixing side plate 8 shown in FIG. 1 is formed such that adjacent two extended sections 16 are overlapped with each other, but it is not limited to; short side 13 may contain a flange part connected to flange 14 on long side 12. In that case, the flange part is bent together with flange 14 so as to form flange 14 on short side 13.

According to the structure of the embodiment, flange 14 shown in FIG. 1 is easily formed by bending without an additional component. Further, flange 14 works as a reinforcement rib, which protects side plate 5 and motor-fixing side plate 8 from a warp or deformation in the direction of the plate surfaces.

Flange 14 shown in FIG. 2 is formed of extended sections 16 overlapped with each other. When the side plate is carried on and suspended for fixing while flange 14 is being held, the direction in which the force is exerted agrees with the connecting direction of adjacent flange 14. This increases the strength of flange 14.

The structure increases the strength of side plate 5 and motor-fixing side plate 8 shown in FIG. 1, allowing centrifugal blower 1 to be fixed as a self-standing structure by casing 2 alone. Such structured centrifugal blower 1 is directly amounted on air conditioners and the like. Besides, the structure eliminates the need of buffer material for protecting corners when centrifugal blower 1 is packed, reducing the package volume of the product.

INDUSTRIAL APPLICABILITY

The present invention is applicable not only to centrifugal blowers but also to packing of various devices.

REFERENCE MARKS IN THE DRAWINGS

1 centrifugal blower

2 casing

3 impeller

4 suction opening

5 side plate

6 scroll

7 motor

8 motor-fixing side plate

9 suction air

10 discharge opening

11 discharge air

12 long side

13 short side

14 flange

15 bend section

15a bend line

16 extended section

17 bottom

18 container box

19 space

20 four corners

20a edge

Claims

1. A centrifugal blower comprising:

a casing having a scroll, a side plate having a suction opening, and a motor-fixing side plate on which a motor is mounted; and

an impeller incorporated in the casing, wherein the impeller is fixed to the motor, and each of the side plate and the motor-fixing side plate has an outer shape of a rectangle with four corners cut off.

2. The centrifugal blower of claim 1, wherein each of the side plate and the motor-fixing side plate has a flange standing upright like a wall on a periphery of the plate.

3. The centrifugal blower of claim 2, wherein each of the side plate and the motor-fixing side plate has a bend section that is a line connecting adjacent edges of the four corners, and the flange is formed parallel to the bend section in a manner that the plates is bent outwardly at the bend section.

4. The centrifugal blower of claim 3, wherein the flange has extended sections extended from both ends of the bend section, and the extended sections are overlapped with each other to form the flange.

5. The centrifugal blower of claim 4, wherein the four corners are cut off in an identical shape.

6. The centrifugal blower of claim 1, wherein each of the side plate and the motor-fixing side plate has an octagonal outer shape.