JPS61205394A - Centrifugal arranged and opposed balance type gas blower - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to centrifugal blowers for extracting or inhaling gas and pressurizing it for transporting it through a pipeline system at relatively high flow rates, and more particularly to The present invention relates to a centrifugal gas blower including inlet and outlet openings aligned across a power shaft and opposing axially spaced impellers. The plant is capable of providing a relatively high level of vacuum up to 18 inches of mercury in its population.

BACKGROUND OF THE INVENTION Centrifugal blowers are known in the art that can be used to pressurize a gas, such as methane gas, and transport it through a pipeline system at relatively high flow rates. However, such blowers rarely have long operating lives, do not have relatively low inlet vacuums, and are usually arranged in configurations that produce highly unbalanced shaft end thrust forces on the blower shaft. As a result, there was a risk of bearing wear and damage. Repair of these prior art blowers is generally difficult.

SUMMARY OF THE INVENTION The present invention utilizes opposing balanced impellers configured and arranged to provide aligned inlet and outlet gas flow through the blower, resulting in minimal or no thrust force on the bearings in the blower. To provide a centrifugal blower that guarantees a longer operating life for the blower and its bearings. The blower of the present invention is particularly suited for applications where gas must be extracted and pressurized and transported through a pipeline system at relatively high flow rates.

Accordingly, it is an object of the present invention to provide an improved centrifugal blower that is capable of efficiently supplying gaseous fluids, such as methane gas, to a pipeline system.

In one embodiment of the present invention, a blower housing includes a pair of axially spaced chambers (plenum chambers) each having an impeller rotatably housed therein. A mounted blower shaft axially extends the housing.

Each of these chambers has a gas inlet for supplying gas to the blower and a gas outlet for discharging pressurized gas from the blower, with each inlet and outlet for each chamber aligned transversely to the axis. This arrangement results in a minimal thrust force being applied to the shaft during operation of the blower, resulting in a longer service life of the blower and the bearings around its shaft.

A novel configuration is provided in the blower for quickly removing the bearing from the blower without disassembling the entire blower.

Hereinafter, specific examples of the present invention will be described with reference to the drawings.

Referring to the drawings, both axial or longitudinal ends 14.1
A centrifugal blower 10 is shown with a fixed housing 12 opening at 6 (FIG. 2). End cap members 18 are provided to close these housing open ends. The end cover member 18 (Figures 2.4 and 5) includes each end cover member 1B.
O-rings 20, gaskets, or other conventional sealing means are installed to seal the joint between the housing 12 and the respective open ends of the housing 12 to prevent gas from escaping through the joint. A screw fastening means 21 is attached to the end cover member 1 to the housing 12.
8 is provided for removably fixing it in a fluid-tight relationship.

A rotatable shaft 22 extends axially or longitudinally through the housing 12 and projects into a spaced apart chamber (plenum chamber) 24,26 defined by the nousing.

Each of the end cap members 18 in the illustrated embodiment includes an integral barrier 28 secured by a connecting hub portion 29. The barrier 28 is circular in its outer circumference (FIG. 4).

Barrier 28 in the illustrated embodiment includes a generally radially extending inner portion 30 and a generally diagonal IC attached thereto.
[It is composed of an outer portion 30a that is present]. The outer portion 30a slopes inwardly from the inner portion 30 and cooperates therewith to define a relatively shallow recess 32 (FIG. 5).

The recesses 32 are adapted to receive impellers 34 or 54a (FIG. 2) associated with their respective chambers in a cooperating but rotatable relationship. A respective end cap member 1B is attached to a respective open end of the housing 12 to close it thereon and when fastened thereto by the fastener 21, each end cap member associates a respective barrier. Set it at an appropriate location indoors to work with the impeller.

With particular reference to FIGS. 6-8 in conjunction with FIG. 2, each impeller 34 or 54a, in the illustrated embodiment,
0 is provided with a backing plate 3B in the form of a circular peripheral edge integrally formed with the backing plate 3B. The backing plate 38 includes a radially extending portion 42;
and an outer diagonally inward extending portion 42a, the latter being the aforementioned diagonal portion 30.3 of the barrier 28 of the end cap member 18.
It has a shape that is similar to that of 0a.

In the illustrated embodiment, the outer diagonal portion 42a is at an angle X, or about 221. /,.

and [as for the corresponding part of the barrier]. It can be seen that the gap between the impeller and the barrier is preferably on the order of about The shafts and impellers are arranged so as to closely follow the internal contours of the respective chambers defined by the housing 12. Preferably, the components are precisely balanced before assembly into the housing.

The impeller vanes 44 are rearwardly oriented and extend diagonally and arcuately outwardly from the hub 40 to a point 46. The vanes 44 are integrally attached to the inside of the backing plate 38. The impeller illustrated in FIGS. 6-8 is the left-hand impeller with respect to FIG. 2, and the other or right-hand impeller is a mirror image thereof. As clearly shown in Figures 6 and 8,
The impeller vanes 44 extend arcuately and radially outwardly from their respective points 46 and away from the vertical plane of the inner surface 50 of the hub 40 to an outward position 54 and backing plate 38 .
slopes upward to the point of connection with the outer end of the diagonal portion 42a. At the outer end of each vane 44, the vane 5 is shown in FIG. 6 to help prevent noise associated with centrifugal displacement.
It is curved at 56 in the direction of rotation of the impeller. Feather 44
As will be explained later, defines a flow path through which gas flows after being taken into the blower.

The outer surface of each vane is recessed at 581C for cooperation with the inner bearing cap 6o (FIGS. 7 and 8).

Each impeller 54.54a is keyed as indicated by reference numeral 64 on the blower power shaft 221C (FIG. 2).

As best seen in FIG. 2, the shaft 22 includes a generally central shoulder portion 66 adapted to abut the inner surface of the hub 40 of each impeller.

a circular bushing 68 cooperating with the outer surface of each impeller;
is provided in the circular recess 58.

A set of threaded tapped holes 70 are formed spaced apart radially outwardly of the recess 58 in each impeller. Hole 7
0 is at a constant radial distance from the axis of each impeller.

Each bearing assembly 71 rotatably supports a shaft and associated impeller relative to a fixed housing. In the illustrated embodiment, the bearing assembly 71 includes an inner bearing cap 60 that surrounds the bushing 68 and is received within a recess 58 in each impeller, and a threaded fastener 78 on each end cap member 18. and an outer bearing cap (cover) 76, 76a adapted to be equally secured.

The outer bearing cap 76, as best seen in FIGS. 2 and 10, includes an enlarged opening 80 through which the shaft 22 extends to the outside of the blower as shown in FIG. Opening 81C preferably has a spring seal member 82 disposed in a recess in outer bearing cap 76, as shown in FIG. The outer end of the shaft 22 is K-shaped so that the shaft 22 and its mounting can be directly connected to the prime mover P for rotation of the impeller 34, 34a.

As can be seen from FIG. 2, the outer bearing cap 76a at the right end of the 1P4W is different from the left end in that the shaft 22 does not extend through it and therefore does not have a large opening but a small opening 84. The outer bearing cap 76 shown in FIG. The aperture 84 is preferably threaded and has a removable threaded member 84a received therein in a substantially fluid-tight relationship.

The shaft 22 is threaded at its outer peripheral portion 86.86a and adapted to cooperate with an associated threaded locking nut 88. Furthermore, a locking washer 89 is preferably provided to cooperate with the locking nut 88 to positively secure and position the dual roller bearing member 90. Bearing member 90
The shaft 22 and its mounting relative to the fixed housing and associated barrier 28 provide rotation of the impeller 54.34a. A conventional spring seal 92 is provided between each inner bearing cap 72 and bushing member 68.

Additionally, the O-ring seal 93 is connected to the outer bearing cap 76.
．． 76 a and the hub of each end cap member 18 .
It can be installed as shown in the figure.

If it becomes desirable or necessary to replace the bearing assembly 71 in the blower, this can be accomplished without disassembling the entire blower. Outer bearing cap 76.
76a is removed by removal of the associated screw fastener 78 and the rear locking nut and locking washer 88,89 are removed from their respective shaft ends, clearing the path of outward axial movement of the bearing member 90. be excluded.

A suitable conventional "puller" or similar mechanism (not shown, but similar to a gear puller) may then be utilized using each shaft end as a bearing point. A long threaded bolt is inserted through a hole 94 through each end cap member 18 and associated barrier 28 and threaded into a threaded hole 70 in each impeller. The screw fasteners 21 can then be removed from the end cap members 18 such that the end cap members and associated barriers 28 are no longer secured to each end of the blower housing 12. The extractor is then actuated to completely remove the impeller, bearing assembly, and integral end cap member and barrier from the shaft 22 and extract it out of the housing, allowing convenient replacement or repair of the bearing assembly. . New or repaired bearing assembly 71
is assembled with the rear end cap and barrier and impeller and transferred axially inwardly into the housing along shaft KG, reassembling the impeller, bearing assembly, end cap member and barrier into position on the shaft. A key 64 is then received within a key slot 96 in the impeller to re-secure the impeller to the shaft. The fasteners 21 are reinserted to secure the end cap member to the housing and the rear securing washers and securing nuts 88,89 are replaced around the shaft ends and the outer bearing caps 76,76
8 are returned and fastened to the respective end cap members by respective fasteners 7B) 1c. In this way, the bearings of the blower can be conveniently replaced or repaired without the need for complete disassembly of the entire blower.

2 and 3, a gas inlet 104 is provided for admitting gas into the blower housing and an aligned gas outlet 106 is provided for discharging pressurized gas from the blower housing. is located on the opposite side across the axis 22 of. A wall f08 extending transversely with respect to the longitudinal axis of the blower divides the inlet 104 and the outlet 106 into two completely compartmentalized compartments so that the incoming gas flows through the left and right impellers of the blower. As shown by the arrows in FIG. 3, the air flows in approximately equal amounts to 5, and is discharged from the left and right chambers of the blower to the outside of the outlet 106 in approximately equal amounts. This avoids internal turbulence which would otherwise create additional heat. Crossing wall 1
08 includes an opening 118 through which the blower drive shaft passes.

A wall 111 closes off the inlet section 115 of the blower housing.

As seen in Figures 1.5.9 and 10,
12 is formed in each chamber 24 , 26 and opens into a respective blower housing outlet section 114 . The outlet openings 112 are preferably vertically elongated, as shown in FIGS. 1 and 9, and communicate the respective chambers with an outlet section 114 of the blower housing. The housing periphery at the blower inlet section 115 is generally cylindrical as best seen in FIG. 2, while the outlet section 114 is defined by walls in the form of a box and as shown best in FIG. There are generally planar upper and lower wall members 118, 119. However, exit hole 119a (FIG. 9) preferably has a circular shape and is the same size as the circular entrance hole in inlet 104. The upper and lower wall members 118, 119, as well as the side wall members of the outlet compartment, merge smoothly into the outlet hole 119a.

According to the invention, the inlet 104 to the blower and the outlet 106 from the blower are in a straight line across the axis 22;
With such a configuration and an opposing balanced impeller arrangement, there is essentially zero thrust on the bearing structure during operation of the blower. As shown in FIG. 3, gas is introduced into each inlet section 115Vc, flows through the flow path of each impeller, flows through a barrier cooperating with each impeller into the associated chamber, and after exit section 115Vc. Flows into 114.

Each end cap member preferably includes a threaded hole 121 suitable for receiving a conventional pressure relief valve to provide pressure relief to the respective chambers of the blower. Such relief valve devices are commercially available and may be purchased from Fisher Control Company, Inc., for example. Such valves are approximately 20 psi
can be set to open at giC to release pressure within each chamber.

Referring now to Figures 1.2 and 10, cooling and reinforcing ribs 122 are preferably provided extending outwardly from the blower body 124 and between the chambers 24.26, and these ribs are It merges with the outer periphery of the chamber. Also,
Each of the endcap members 18 is preferably provided with an outer vertical distraction lip 126 that aids in removing heat from the blower while reinforcing the walls of the endcap member.

The illustrated blower receives gas at a minimum pressure at an inlet 104 and at an outlet 106, e.g.
Adapted to emit gas at a pressure of ~s psig and a flow rate of about 3400 ft'$. The shaft is 3000~1α000 r to realize various expulsion pressures and vacuums,
It can be rotated in the range p, m. The blower may conveniently be made from an aluminum alloy so as to have a low noise level during operation and to provide a relatively lightweight blower device for improved portability.

The bearing assembly 71 has a respective outer bearing cap 76.7.
It can be kept lubricated by conventional lubricant supply means placed behind 6a.

From the foregoing, the present invention includes a housing that defines a pair of axially spaced chambers, an impeller is rotatably disposed in each of the chambers, and the housing extends axially and faces each other. A shaft on which the impeller is attached is provided, and a gas inlet and a gas outlet communicating with each chamber and a gas outlet communicating with each chamber, the gas inlet and the outlet being arranged in an aligned relationship across the axis. It will be appreciated that the present invention provides a novel centrifugal blower in which the thrust forces on the shaft and associated bearings during operation of the blower are minimized. The present invention is also suitable for transferring gas through a line system, e.g. at relatively high flow rates, and also provides a means for expediently replacing and repairing the bearing structure of the blower without requiring disassembly of the entire blower. It also provides a lightweight blower mechanism.

Although the invention has been described above, it is to be understood that many modifications may be made within the scope of the invention.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view (from the right side of FIG. 2) of a gas blower embodying the present invention. FIG. 2 is a front longitudinal cross-sectional view of the blower of FIG. 1, showing the shaft and impeller connected to the prime mover. FIG. 3 is a horizontal sectional view taken along line 3-5 in FIG.
Only the housing form is shown with the shaft, bearing assembly, and impeller omitted. FIG. 4 is a side view of an end cap member used to close the open end of the housing. FIG. 5 is a cross-sectional view of I/c overflow 5 taken along line 5-5 in FIG. FIG. 6 is a front view of the inside of the left impeller (with respect to FIG. 2) of the blower. FIG. 7 is a partial view of the opposite or outer side of FIG. 6. FIG. 8 is a sectional view taken along line 8-8 in FIG. 6. FIG. 9 is a partially cutaway front view of the blower housing. 10 is a partially cutaway side view of the blower from the left side of FIG. 2. FIG. 11 is a partially cutaway side view of the blower from the right side of FIG. 2. FIG. FIG. 12 is a sectional view taken along line 12-12 in FIG. 3. 10 Ni blower 12: housing 18: end cover member 22: shaft 24.26; chamber 28: barrier 5a, saa: impeller 38: backing plate 44: vane 71: bearing assembly 104: gas inlet 106: gas exhaust Exit 108: Dividing wall 112: Exit opening P: Motor supply; ↓ ↓ 9

Claims (1)

Claims: 1) a housing comprising a pair of axially spaced chambers, a shaft extending axially into the pair of chambers, and a shaft attached to the shaft and each of the chambers; an impeller rotatably arranged in the housing, the housing includes a gas inlet to each of the chambers and a gas outlet from each of the chambers, and the gas inlet and the outlet are connected to each other. A centrifugal blower arranged in alignment across said shaft, thereby minimizing shaft end thrust during operation. 2) A patent in which spaced bearing means are provided within the housing for rotatably mounting the shaft relative to the housing, and means are provided for rapid removal of the bearing means from the shaft end without requiring disassembly of the entire blower. A blower according to claim 1. 3) the housing includes a dividing wall dividing one side and the other side thereof perpendicularly to the longitudinal axis of the housing, the inlet consists of a single opening and the outlet consists of a single opening; A blower according to claim 1, wherein a dividing wall divides the inlet and outlet openings into separate inlets and outlets for each chamber. 4) The blower according to claim 1, wherein the housing is open at both longitudinal ends thereof and includes end cap members for removably closing each of the housing openings. 5) each impeller includes a backing plate and a vane extending generally helically outward in the direction of one rotation of the impeller and secured to the backing plate, the outer end of each vane comprising: extending outwardly in an arc to a predetermined point with respect to the plane of the backing plate and then curving inwardly toward the plane and radially outward in a circumferential direction of the backing plate; The blower according to claim 1, which extends obliquely so as to merge with the blower. 6) the barrier is attached to the interior of the end cap member by a hub portion extending axially, the shaft mounting each impeller adjacent the interior surface of the respective barrier and adjacent the facing surface of the housing; 5. The blower according to claim 4, wherein the impeller rotates against each barrier indoors. 7) The blower according to claim 6, wherein the outer periphery of the barrier is arranged at a longer radial distance than the radial distance from the axis of the shaft to the outer periphery of the impeller. 8) the barrier includes a radial portion extending outwardly from the hub portion and a portion extending diagonally inwardly therefrom, the impeller includes a backing plate formed substantially along the barrier, and the impeller blades include a backing plate formed substantially along the barrier; 7. The blower according to claim 6, wherein the blower is fixed to the inside of the backing plate and forms a generally spiral shape outwardly in the rearward direction with respect to the rotational direction of the impeller. 9) the facing surface of the housing includes a barrier portion surrounding a portion of the impeller adjacent an inner end thereof, the barrier portion being spaced axially inwardly from the barrier; The shaft is rotatably mounted at the relevant end of the housing and is spaced axially outwardly from the shielding portion, and the shaft end can be removed from the housing without requiring disassembly of the entire blower to assemble the end cap member and bearing assembly. and a means for axially removing the impeller is formed on the impeller and the end cap member. 10) The impeller is rotatable in its respective chamber with rotation of the shaft, and the bearing means cooperates between the shaft and the end cap member for anti-friction rotation of the shaft relative to the housing. The blower according to item 4. 11) Each end cap member has a circular plate member adjacent the periphery and having a generally circular outer peripheral configuration and axially spaced from said outer circular plate member. a dish-shaped cross-sectional shape such that the barrier receives a similarly shaped portion of the impeller backing plate in cooperating and intimate relationship; and a spaced apart bearing assembly adjacent each end of the housing reduces friction of the shaft relative to the housing and the end cap and barrier. 5. A blower as claimed in claim 4 providing rotational action. 12) An opening passing through the outer plate-like member, a cover for the opening, and means for removably connecting the cover to the outer plate-like member are provided, and when the cover is removed, the shaft end is exposed, and each 12. A blower as claimed in claim 11, allowing access to the bearing assembly at the shaft end. 13) A blower according to claim 12, further comprising sealing means cooperating to retain lubricant between the shaft and the bearing assembly. 14) An impeller is fixed to the hub and extends radially a predetermined distance therefrom, including a hub, means provided on the hub for attaching the impeller to the shaft, and diagonally inwardly so as to define a rear dished configuration. a backing plate extending from the backing plate; and an impeller is secured to the backing plate and includes vanes spiraling rearwardly and outwardly from the hub and terminating adjacent the outer periphery of the backing plate. a barrier curved along the facing surface of the housing and disposed between the housing facing surface and the backing plate, the facing surface surrounding the inner end of the impeller and guiding and conducting gas from the inlet; 8. A blower as claimed in claim 7, including a vertically elongated outlet opening communicating each chamber with the outlet.