JPH1162600A - Centrifugal fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent occurrence of abrasion and seizure by preventing leakage of oil and fluid. SOLUTION: This type of fluid machine has an impeller 65 the arranged inside a housing, an oil chamber arranged adjacently to the housing, an impeller shaft penetrating them, a collar 103 fixed to the penetration side, a bush 63 fixed to the side of the shaft 35, and a piston seal 105 arranged between the collar 103 and the bush 63. The collar 103 is formed with a female screw 3 109 and a circumferential groove 111, while the bush 63 is formed with a male screw 113 and a circumferential groove 115. Relative turning is performed until the male screw 113 completely passes over the female screw 109, and both the female screw 109 and the male screw 113 are housed in the circumferential grooves 115, 111 on the opposite side. At that position, the shaft 35 is held by a labyrinth seal 107 whereby oil leakage from the oil chamber and fluid leakage from the housing are prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifugal fluid machine used as a compressor or an expander.

[0002]

2. Description of the Related Art A mechanical supercharger 201 as shown in FIG. 3 is described in JP-A-8-189369.

[0003] This mechanical supercharger 201 has an input pulley 2
03, a planetary gear type speed increasing mechanism 205, and a centrifugal air compressor 207 (centrifugal fluid machine).

The driving force of the engine for rotating the input pulley 203 is increased by a speed increasing mechanism 205 to rotate the impeller 211 at a high speed via an impeller shaft 209.

[0005] The bearing 213 of the impeller shaft 209 and the speed increasing mechanism 205 are housed inside a casing 215. Bearing 213 of impeller shaft 209 rotating at high speed
Is pressurized oil and lubricated, and the impeller shaft 209 is flown by the pressurized oil.
Ting is supported. The speed increasing mechanism 205 is also lubricated by this oil.

The leakage of fluid from the compressor housing 217 of the air compressor 207 and the casing 21
5 to prevent oil leakage from
A piston seal 223, which is a contact type seal, is disposed between the collar 219 on the 15th side and the bush 221 on the impeller shaft 209 side.

Further, in order to prevent leakage of the fluid from the compressor housing 217, a non-contact type seal axially opposed between the rear surface of the large diameter portion of the impeller 211 and the casing 215. A labyrinth seal 225 is provided.

[0008]

However, a negative pressure may be generated on the compressor housing 217 side during the operation of the air compressor 207 or at the time of stoppage. The effect is insufficient.

Further, the floatingly supported impeller shaft 209 moves in the axial direction during the operation of the air compressor 207 or at the time of starting and stopping, so that the impeller shaft 209 comes into contact with the labyrinth seal 225 which is disposed to face the axial direction. In this case, since the sliding speed is high, the gap changes due to wear. Therefore, it is necessary to secure a sufficient labyrinth length to obtain a sufficient sealing effect.

Accordingly, an object of the present invention is to provide a centrifugal fluid machine capable of sufficiently preventing oil leakage from an oil chamber disposed adjacent to a housing and fluid leakage from a housing and preventing abrasion and seizure. I do.

[0011]

According to a first aspect of the present invention, there is provided a centrifugal fluid machine, wherein a fluid inlet and a fluid are provided at both ends of a spiral fluid flow path whose cross-sectional area perpendicular to the moving direction of the fluid changes toward one side. A housing provided with an outlet, an impeller rotatably arranged inside the housing, an oil chamber arranged adjacent to the housing, a shaft of the impeller penetrating from the oil chamber to the housing; A centrifugal fluid machine having a collar fixed to the inner side, a bush fixed opposite to the collar on the impeller shaft side, and a piston seal for sealing a gap between the collar and the bush. A female screw and a circumferential groove are formed in the collar in the axial direction, and a male screw and a circumferential groove capable of meshing with the female screw of the collar are formed in the bush in the axial direction, thereby assembling the impeller shaft. By rotating the engaged female screw and the male screw relatively to each other until they pass through each other, and holding the impeller shaft at a position where the female screw and the male screw are accommodated in the respective circumferential grooves of the bush and the collar, the female screw and the circumferential groove of the bush are formed. And between the external thread and the circumferential groove of the collar,
A labyrinth seal is formed to prevent oil leakage from the oil chamber and fluid leakage from the housing.

As described above, at the penetrating portion between the housing and the oil chamber, the female screw and the male screw and the circumferential groove which can be engaged with each other are formed on the collar on the penetrating portion side and the bush on the impeller shaft side. At the time of attachment, after the interlocked female screw and male screw are relatively rotated until they pass through each other, the female screw is housed in the circumferential groove of the bush, and the impeller shaft is held at a position where the male screw is housed in the circumferential groove of the collar. A labyrinth screen between the female screw and the bush and between the male screw and the collar.
Is formed.

By providing such a labyrinth seal in addition to the sealing effect of the piston seal, the effect of preventing oil leakage from the oil chamber and fluid leakage from the housing is greatly improved.

The path of the labyrinth seal has a small diameter path formed between the tip of the thread of the female screw and the circumferential groove of the bush, and the path between the tip of the thread of the male screw and the circumferential groove of the collar. Is formed by repetition of a large-diameter path formed on the entire surface, so that the whole is largely meandering in the radial direction.

On the other hand, the conventional labyrinth seal, which is arranged radially opposite at the shaft portion, cannot be assembled.
Alternatively, it is difficult to meander the path in this way due to cost considerations.

Therefore, the labyrinth seal provided in the centrifugal fluid machine of the present invention has an extremely high seal compared with the conventional one because the flow path resistance is strengthened by the large meandering path. Property is obtained.

The labyrinth seal arranged radially oppositely on the impeller shaft is different from the labyrinth seal 225 of the conventional example arranged axially oppositely when the impeller moves in the axial direction. However, there is no contact and, therefore, no wear or seizure occurs.

The labyrinth seal disposed on the impeller shaft has a small diameter. Unlike the large-diameter labyrinth seal 225 in the conventional example, when the impeller shaft moves in the radial direction and a contact occurs. However, since the sliding speed is low, wear and seizure hardly occur, and the durability is excellent.

The labyrinth seal whose path is largely meandered in the radial direction has a female screw and a circumferential groove formed on the collar, and a male screw and a circumferential groove formed on the bush as described above. By accommodating a male screw in the circumferential groove of the bush and a female screw in the circumferential groove of the bush, it can be implemented with only two members, a color and a bush, and can be implemented at extremely low cost. Machines have lower costs.

Further, the assembly of the impeller shaft for rotating the bush (impeller shaft) until the male screw passes through the female screw is simple, and the operation cost is reduced.

The centrifugal fluid machine of the present invention is provided with a labyrinth seal having high sealing performance and excellent durability as described above, thereby preventing leakage of intake air and maintaining high efficiency. At the same time, the durability is greatly improved.

In the centrifugal fluid machine of the present invention, oil leakage is effectively prevented by the piston seal and the labyrinth seal, so that the durability of each lubricating portion inside the casing is improved and In addition, mixing of oil into the fluid is reduced.

Further, the centrifugal fluid machine of the present invention is suitable for applications such as a compressor for compressing a refrigerant in a refrigerator or a cooling device because oil is less mixed into the fluid.

According to a second aspect of the present invention, there is provided the centrifugal fluid machine according to the first aspect, wherein the step of the external thread pushes oil leakage back to the oil chamber side with the rotation of the impeller shaft, and the direction of the external thread step. Is formed, and the same effect as the configuration of claim 1 is obtained.

As described above, the rotation of the male screw pushes oil leakage back to the oil chamber side during the operation of the centrifugal fluid machine, so that the sealability of the labyrinth seal is further improved.

According to a third aspect of the present invention, there is provided the first or second aspect.
In the centrifugal fluid machine according to the present invention, at least one of the female screw and the male screw is formed at a plurality of positions with the circumferential groove interposed therebetween, and an effect equivalent to the configuration of claim 1 or 2 is obtained.

In addition, by forming one or both of the female screw and the male screw at a plurality of locations, the flow path resistance is increased, so that the sealing property of the labyrinth seal is improved accordingly.

The invention according to claim 4 is the invention according to claims 1 to 3.
4. The centrifugal fluid machine according to claim 1, wherein the axial width of the male screw or the total thereof is longer than the axial width of the female screw or the total thereof, and is equivalent to any one of claims 1 to 3. Get the effect.

In addition to this, the axial width of the male screw or the total thereof is made longer than the axial width of the female screw or the total thereof. The effect of pushing back increases,
The sealability of the labyrinth seal is further improved.

The invention of claim 5 is the invention of claims 1 to 4
5. The centrifugal fluid machine according to claim 1, wherein the female screw and the male screw are arranged between the piston seal and the impeller, and the same effects as in any one of claims 1 to 4. Get.

In addition, the oil that leaks slightly from the piston seal is blocked by the labyrinth seal having a high sealing effect as described above, so that oil leakage can be effectively prevented. .

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. This embodiment has the features of claims 1, 2, and 5. Hereinafter, the left and right directions are the left and right directions in FIG. 1, and members without reference numerals and the like are not shown.

FIG. 1 shows a mechanical supercharger 1, which comprises an input pulley 3, a planetary gear type speed increasing mechanism 5, and a centrifugal air compressor 7 (embodiment). Centrifugal fluid machine).

The input pulley 3 includes a pulley body 9 and a hub 11.
The hub 11 is fixed to the input shaft 15 of the speed increasing mechanism 5 with a key 17 and a nut 19. The input pulley 3 is connected to a pulley on the crankshaft side via a belt, and is driven to rotate by the driving force of the engine.

The input shaft 15 is mounted on a casing by a bearing 21.
The input shaft 15 is supported by the boss 25 of the thing 23.
A lip seal 27 is disposed between the casing and the casing 23.

The speed-increasing mechanism 5 includes a flange 2 of the input shaft 15.
The air compressor 7 includes an internal gear 31, a plurality of pinion gears 33 arranged at regular intervals in the circumferential direction, and a sun gear 37 formed on an impeller shaft 35 of the air compressor 7.

The pinion gear 33 is supported on a pinion shaft 41 via a bearing 39. The pinion shaft 41 is supported through a flange member 43 fixed to the casing 23.

An oil seal 45 is arranged between the casing 23 and the flange member 43 to prevent oil from leaking to the outside.

The casing 23 and the flange member 43
Is a connecting member 49 engaged with the peripheral groove 47 of the casing 23.
And a bolt 51 for fixing the connecting member 49 to the flange member 43.

The compressor housing 53 (housing) of the air compressor 7 and the flange member 43 are fixed to each other by a fixing ring 55 mounted on the outer periphery of each.

The sun gear 3 is provided on the impeller shaft 35.
From the right side of 7, ring 57, ring 59, spacer 6
1, the bush 63, the impeller 65 are mounted, and the nut 6
It is fixed at 7.

The speed increasing mechanism 5 increases the driving force of the engine input from the input pulley 3 to the internal gear 31 through the sun gear 37 from the pinion gear 33, and drives the impeller shaft 35 (impeller 65) to rotate at high speed. I do.

The air compressor 7 draws intake air from a suction port 69 (inflow port) by the rotation of the impeller 65, and the sucked intake air is centrifugal force of the impeller 65 and the swirl chamber 71 of the compressor housing 53 (swirl type fluid flow path). ) To be pressurized and discharged from the discharge port (outflow port) to supercharge the engine.

The flange member 43 includes a bearing holder 7
3 is press-fitted and fixed to the flange member 43 by screws 75.

The bearing holder 73 comprises a cylindrical portion 77 and a conical convex portion 79. The convex portion 79 penetrates through a small gap into a conical concave portion 81 formed on the input shaft 15 side.

The sun gear 3 is provided on the impeller shaft 35.
7, a sliding bearing 83 is disposed on the left side of the spacer 61.
A sliding bearing 85 is disposed on the outer periphery of the bearing holder 73.
The impeller shaft 35 is supported between the inner circumference of the cylinder 9 and the inner circumference of the cylindrical portion 77.

A thrust washer 87 is mounted on the bearing holder 73 from the outside in the radial direction. The thrust washer 87 is engaged with a groove 89 formed between the rings 57 and 59, and a thrust washer of the impeller shaft 35 is formed. Receiving power.

Between the slide bearings 83 and 85 and the bearing holder 73, an oil plug 91 and a nozzle 93 attached to the casing 23 from an external oil pump and a bearing holder 73 and a flange member 43 are formed. Pressurized oil is supplied through an oil passage 95 to form an oil film damper.

Each of the sliding bearings 83 and 85 is floatingly supported by the oil film damper, and supports the impeller shaft 35 while absorbing vibration. This pressurized oil is also supplied to the groove 89 via the oil passage 97 to lubricate the sliding portion with the thrust washer 87,
Is supplied to the lip seal 27 through the oil passage 99 for lubrication.

The casing 23 (oil chamber) accommodating the speed increasing mechanism 5 and the compressor housing 53 of the air compressor 7 are formed by a flange member 43 and a bearing holder 73.
Is divided by

The impeller shaft 35 is, as described above,
The bearing holder 73 is penetrated, and a collar 103 made of an iron-based material is press-fitted into a through hole 101 (through portion) of the bearing holder 73. The bush 63 on the impeller shaft 35 is disposed inside the collar 103 so as to face the same.

As shown enlarged in FIG. 2, a piston seal 1 is provided between the collar 103 and the bush 63.
Numeral 05 is provided to prevent oil leakage from the casing 23 and intake air leakage from the air compressor 7.

In addition, the color 103 and the bush 6
A labyrinth seal 107 is formed between the labyrinth seal 107 and the labyrinth seal 3.

A female screw 109 and a peripheral groove 111 are formed in the inner periphery of the collar 103 in the axial direction, and a male screw 113 and a peripheral groove 115 are formed in the outer periphery of the bush 63 in the axial direction. The female screw 109 and the male screw 113 can engage with each other. The circumferential groove 111 of the collar 103 is
The external groove 113 of the bush 63 can accommodate the female screw 109 of the collar 103.

The female screw 109 and the male screw 113 can pass through each other by providing the circumferential groove 111 and the circumferential groove 115 in the respective axial directions as described above.

When assembling the impeller shaft 35, the male screw 113 is engaged with the female screw 109, and the bush 63 (the impeller shaft 35) is rotated until the male screw 113 passes to the left of the female screw 109. And the female screw 109 is
The impeller shaft 35 is positioned at a position where the impeller shaft 35 is accommodated.

The labyrinth seal 107 has a male screw 113
And a path 119 between the internal thread 109 and the peripheral groove 115.

The path 117 has a large diameter because it is formed between the tip of the thread of the male screw 113 and the peripheral groove 111, and the path 119 has a large diameter between the tip of the thread of the female screw 109 and the peripheral groove 115. It has a small diameter because it is formed in

As described above, in the labyrinth seal 107 formed by repeating the large-diameter path 117 and the small-diameter path 119, the entire path is largely meandering in the radial direction. Is strengthened,
Extremely high sealing properties can be obtained.

The labyrinth seal having a high sealing property as described above
The provision of the valve 107 effectively prevents oil leakage from the casing 23 even when the compressor housing 53 side becomes negative pressure, and also prevents leakage of intake air from the compressor housing 53.

The progress of the male screw 113 is caused by the rotation of the impeller shaft 35 (male screw 113) so that the oil
It is formed so as to be pushed back to the shing 23 side (the slide bearing 85 and its oil film damper side).

The labyrinth sheet is formed by this pushing back action.
The effect of preventing the oil leakage of the screw 107 is further improved.

Since the labyrinth seal 107 is arranged between the piston seal 105 and the impeller 65, even if oil leaks slightly from the piston seal 105, the leaked oil is removed by the labyrinth seal 107. Since it is shut off and further pushed back, the effect of preventing oil leakage is extremely high.

Thus, the mechanical supercharger 1 is configured.

As described above, the labyrinth seal 107 provided in the mechanical supercharger 1 has a high sealing property by making the paths 117 and 119 meander in the radial direction greatly and enhancing the flow path resistance. ing.

The labyrinth seal 107 radially opposed on the impeller shaft 35 is different from the conventional labyrinth seal 225 axially opposed to the labyrinth seal 225 in that the impeller 65 is arranged in the axial direction. When moving, there is no contact, and therefore no wear or seizure occurs.

The labyrinth seal 107 is reduced in diameter by being arranged on the impeller shaft 35, and unlike the large-diameter labyrinth seal 225 in the conventional example, the impeller shaft 35 moves in the radial direction. Even when contact occurs, wear and seizure hardly occur due to the low sliding speed, and the durability is excellent.

The labyrinth seal 107 in which the paths 117 and 119 meander in the radial direction greatly, as described above,
A female screw 109 and a circumferential groove 111 are formed on the collar 103,
Forming an external thread 113 and a peripheral groove 115 in the bush 63;
Further, a male screw 113 is accommodated in the circumferential groove 111 and the circumferential groove 115 is accommodated.
Since the female screw 109 is accommodated in the mechanical supercharger 1, it can be constituted by only the two members, the collar 103 and the bush 63, and can be implemented at extremely low cost.
Costs have been reduced accordingly.

The bush 63 (the impeller shaft 35) until the male screw 113 passes through to the left of the female screw 109.
Is easy to assemble the impeller shaft.
Work costs are reduced.

Since the mechanical supercharger 1 is provided with the labyrinth seal 107 having high sealing performance and excellent durability as described above, the leakage of intake air is prevented and the efficiency is kept high. At the same time, the durability is greatly improved.

The mechanical supercharger 1 (air compressor 7) includes a piston seal 105 and a labyrinth seal 10
7, the oil leakage is effectively prevented, so that the durability of each lubricating portion inside the casing 23 is improved and the mixing of oil into the intake air (fluid) is reduced.

The air compressor 7 may be used as a compressor for compressing a refrigerant in a refrigerating cycle of a refrigerator or a cooling device, and may be driven by an engine or a motor.

The air compressor 7 in which the mixing of oil into the refrigerant is reduced as described above is suitable for such applications.

Unlike the embodiment, the location of the labyrinth seal may be located closer to the oil chamber than the piston seal (the piston seal may be located between the impeller and the labyrinth seal). Alternatively, a piston seal may be arranged between the internal thread and the external thread of the labyrinth seal.

The centrifugal fluid machine of the present invention can be used not only as a compressor for compressing a fluid by applying a rotational force to an impeller as in the embodiment, but also for rotating a pressurized fluid by expanding the fluid. It may be used as an expander (turbine) for extracting force.

[0076]

According to the centrifugal fluid machine of the first aspect, the labyrinth seal is configured so that the male screw of the bush and the female screw of the collar can pass through each other and meanders largely in the radial direction, so that oil leaks from the oil chamber. And leakage of fluid from the housing is effectively prevented.

The labyrinth seal whose path is meandering in the radial direction can pass through the male screw of the bush and the female screw of the collar as described above, so that only the two members of the collar and the bush are extremely low. Cost-effective implementation is possible, and centrifugal fluid machines are less costly.

Unlike the labyrinth seal of the prior art, the labyrinth seals arranged radially opposite to each other do not come into contact with each other even if the impeller moves in the axial direction, and do not cause abrasion or seizure. .

The small diameter labyrinth seal is different from the large diameter labyrinth seal of the prior art in that even if the impeller shaft moves in the radial direction and a contact occurs, the sliding speed is low, so that the wear and the wear are reduced. Seizure is less likely to occur and the durability is excellent.

Further, the assembly of the impeller shaft for rotating the bush (impeller shaft) until the male screw passes through the female screw is simple, and the operation cost is reduced.

The centrifugal fluid machine of the present invention is provided with a labyrinth seal having high sealing properties and excellent durability as described above, thereby preventing leakage of intake air and maintaining high efficiency. At the same time, the durability is greatly improved.

In the centrifugal fluid machine of the present invention, oil leakage is effectively prevented by the piston seal and the labyrinth seal, so that the durability of each lubricating portion inside the casing is improved and In addition, mixing of oil into the fluid is reduced.

Further, the centrifugal fluid machine of the present invention is suitable for applications such as a compressor for compressing a refrigerant in a refrigerator or a cooling device because oil is less mixed into the fluid. .

According to the second aspect of the present invention, the same effects as those of the first aspect are obtained, and during the operation of the centrifugal fluid machine, oil leakage is pushed back to the oil chamber side by the rotation of the external thread, and the labyrinth system is rotated. -The sealing property of the steel is further improved.

The third aspect of the present invention provides the first or second aspect.
The same effect as the configuration described above can be obtained, and by forming one or both of the female screw and the male screw at a plurality of locations, the flow path resistance increases, and the sealing property of the labyrinth seal improves accordingly.

The invention of claim 4 is the first to third aspects of the present invention.
By obtaining the same effect as any one of the above, and making the axial width of the male screw or the total thereof longer than the axial width of the female screw or the total thereof, in particular, in the configuration of claim 2, the oil chamber is formed by rotation of the male screw. Since the effect of pushing back to the side is increased, the sealing property of the labyrinth seal is further improved.

The invention according to claim 5 is the invention according to claims 1 to 4.
In addition to obtaining the same effect as any of the above, even if the oil leaks slightly from the piston seal, the passage of this oil is blocked by the labyrinth seal having a high sealing effect as described above, so that the oil leaks. Effectively prevented.

[Brief description of the drawings]

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

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a sectional view showing a conventional example.

[Explanation of symbols]

 7 air compressor (centrifugal fluid machine) 23 casing (oil chamber) 35 impeller shaft 53 compressor housing (housing) 61 suction port (inlet) 63 bush 65 impeller 71 spiral chamber (spiral type fluid flow path) 101 through hole (Penetrating portion) 103 Color 105 Piston seal 107 Labyrinth seal 109 Female screw 111 Color circumferential groove 113 Male screw 115 Bush circumferential groove

Claims (5)

[Claims] 1. A housing in which a fluid inlet and an outlet are provided at both ends of a spiral fluid flow path whose cross-sectional area perpendicular to the moving direction of the fluid changes toward one side, and a rotation inside the housing. In the impeller freely arranged, the oil chamber arranged adjacent to the housing, the shaft of the impeller penetrating from the oil chamber to the housing,
A centrifugal fluid machine including a collar fixed to the penetrating portion, a bush fixed to the impeller shaft facing the collar, and a piston seal sealing a gap between the collar and the bush. Wherein the female screw and the circumferential groove are formed in the collar in the axial direction, and the male screw and the circumferential groove capable of meshing with the female screw of the collar are formed in the bush in the axial direction, and when assembling the impeller shaft, The engaged female screw and male screw are rotated relative to each other until they pass through each other, and by holding the impeller shaft at a position where the female screw and male screw are housed in the respective circumferential grooves of the bush and the collar, the female screw and the circumferential groove of the bush are formed. A labyrinth seal is formed between the male screw and the peripheral groove of the collar to prevent oil from leaking from the oil chamber and fluid from the housing. Heart-type fluid machine. 2. The invention according to claim 1, wherein the step of the male screw is formed in such a direction that the step of the male screw pushes oil leakage back toward the oil chamber with the rotation of the impeller shaft. Centrifugal fluid machine. 3. The centrifugal fluid machine according to claim 1, wherein at least one of the female screw and the male screw is formed at a plurality of positions across the circumferential groove. 4. The centrifugal fluid according to claim 1, wherein the axial width of the male screw or the sum thereof is longer than the axial width of the female screw or the sum thereof. machine. 5. The centrifugal fluid machine according to claim 1, wherein the female screw and the male screw are arranged between the piston seal and the impeller. .