JPH06249165A - Scroll fluid machine - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a scroll type fluid machine capable of efficiently cooling a casing from the outside and improving reliability. Structure: A plurality of cooling fins 39, 39, ... Are provided on the outer surface of the casing 36, and a plurality of cooling fins 40, 40 ,. 39, 39, ...
Of the cooling fins 39, 39, ... on the right outer surface of the casing 36 and the fixed scroll 37. The suction duct 41 covering the upper part of the casing 36 communicates with the upper duct 42 covering the upper part and the suction duct 41 and the upper duct 42 via the collecting duct 43 and the like. An outflow duct 50 and an L-shaped duct 51 that cover the cooling fins 40, 40, ... Are provided, and a cooling fan 46 that is rotationally driven by the drive shaft 4 is provided between the collecting duct 43 and the outflow duct 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type fluid machine suitable for use in, for example, a vacuum pump or a compressor.

[0002]

2. Description of the Related Art FIG. 4 shows a scroll type air compressor as an example of a scroll type fluid machine according to the prior art.

In the drawings, reference numeral 1 denotes a casing, 2 denotes a casing body which constitutes the casing 1 together with a front casing 3 which will be described later, and the casing body 2 has a disc-shaped bottom portion 2A and an outer peripheral side of the bottom portion 2A which will be described later. The tubular portion 2B extending toward the fixed scroll 15 side and the tubular bearing portion 2C formed on the inner peripheral side of the bottom portion 2A are formed into a bottomed tubular shape.

Reference numeral 3 denotes a stepped tubular front casing integrally formed by projecting radially inward from the tip end side of the tubular portion 2B of the casing main body 2. The front casing 3 is located on the inner peripheral side thereof. , A thrust receiving portion 3A that receives the load in the thrust direction by slidingly contacting the rear side of the orbiting scroll 7 described later.
And a plurality of notch portions 3B, 3 which are located on the inner peripheral side of the thrust receiving portion 3A and are formed at predetermined intervals in the circumferential direction.
, (Only two are shown) are provided.

Reference numeral 4 denotes a drive shaft rotatably supported by a bearing portion 2C of the casing body 2 via bearings 5 and 6, and the tip end side of the drive shaft 4 extends into the casing 1 to form a crank 4A. The axis of the crank 4A is eccentric to the axis of the drive shaft 4 by a predetermined dimension d. Further, the base end side of the drive shaft 4 is an electric motor (not shown) outside the casing 1.
Etc., and is rotationally driven by this electric motor.

Reference numeral 7 denotes an orbiting scroll which is located in the casing 1 and is provided so as to be capable of orbiting on the crank 4A of the drive shaft 4. The orbiting scroll 7 has a disk-shaped end plate 8 and the end plate 8. It is composed of a spiral wrap portion 9 standing upright from the front surface 8A with the winding start end 9A on the center side and the winding end end 9B on the outer peripheral side, and a boss portion 10 provided in the center of the end plate 8 on the rear surface 8B side. A crank 4A is mounted in the boss portion 10 via a swivel bearing 11.
Further, on the outer peripheral side of the front surface 8A of the end plate 8, there is integrally formed a cylindrical inner supporting portion 12 for supporting a later-described seal member 24 from the inner peripheral side.

Here, a plurality of key grooves 13 are formed on the outer peripheral side of the rear surface 8B of the end plate 8 at predetermined intervals in the circumferential direction, and each key groove 13 and each notch 3 of the front casing 3 are formed.
Between B and the Oldham coupling 14 as a rotation preventing mechanism.
Is provided. When the drive shaft 4 is rotationally driven, the orbiting scroll 7 is given a circular motion having a orbiting radius of dimension d by the crank 4A, and the Oldham coupling 14
The rotation of the drive shaft 4 is prevented by the rotation of the drive shaft 4, so that the drive shaft 4 continues to revolve (revolve).

Reference numeral 15 denotes a fixed scroll provided so as to abut on the front end surface of the front casing 3 so as to cover the front end side of the casing 1, and the center of the fixed scroll 15 is the axis of the drive shaft 4. Similarly to the end plate 16 disposed in the central portion so as to coincide with the front surface 16A of the end plate 16 and the wrap portion 9 of the orbiting scroll 7, the center side is the winding start end 17A.
Thus, the spirally wrapped wrap portion 17 which is provided upright on the outer peripheral side as the winding end 17B and the cylindrical portion which is formed so as to surround the outer peripheral side of the end plate 16 and abuts against the outer peripheral side of the front end surface of the front casing 3. 18 and a suction passage 22 to be described later is provided on the inner peripheral side of the tubular portion 18. The wrap portion 17 of the fixed scroll 15 is overlapped with the wrap portion 9 of the orbiting scroll 7 while being displaced by a predetermined angle (for example, about 180 °).

Reference numerals 19, 19 ... Show a plurality of compression chambers formed between the wrap portion 9 of the orbiting scroll 7 and the wrap portion 17 of the fixed scroll 15, and each compression chamber 19 is a wrap portion of the fixed scroll 15. Orbiting scroll 7 against 17
Is formed so that its volume is gradually reduced during the turning motion of the. The compression chambers 19 take in air from the suction passage 22 by the orbiting scroll 7 revolving and sequentially compress the air.

Numerals 20 and 20 designate the cylindrical portion 1 of the fixed scroll 15.
8 shows the suction ports drilled in 8, and each of the suction ports 20
When the orbiting scroll 7 orbits, the wrap portion 9 communicates with the wrap portion 17 of the fixed scroll 15 and the outermost compression chamber 19 defined by the suction passage 22.

Reference numeral 21 denotes a discharge port formed in the center of the end plate 16 of the fixed scroll 15, and the discharge port 21 communicates with the compression chamber 19 on the most central side (high pressure side).

The reference numeral 22 is provided in the fixed scroll 15 so as to surround the outer peripheral side of the wrap portion 17, and the cylindrical portion 18 is provided.
2 shows an annular suction passage formed on the inner peripheral side of the suction passage 22. The suction passage 22 communicates between the outermost compression chamber 19 and the suction port 20.

Reference numeral 23 denotes a cylindrical outer support portion provided on the outer peripheral side of the front end surface of the front casing 3, and 24 denotes the outer support portion 23.
Provided between the outer peripheral surface of and the outer peripheral surface of the inner support portion 12,
1 shows a seal member formed from a flexible resin material so as to have a U-shaped cross section, the seal member 24 having its inner peripheral side fixed to the outer peripheral surface of the inner support 12 by a fixing ring 25 and its outer peripheral side being outside It is fixed to the outer peripheral surface of the support portion 23 by a fixing ring 26. Then, the seal member 24
Seals the suction passage 22 and the inside of the casing 1 in a gas-liquid tight manner, and prevents the suction passage 22 from communicating with the chamber A inside the casing 1 via the space between the front casing 3 and the orbiting scroll 7.

Reference numeral 27 denotes an oil scraper located inside the casing body 2 and fitted and fixed to the drive shaft 4. The oil scraper 27 has its tip end side covered with oil such as lubricating oil housed in the chamber A of the casing 1. It is arranged so as to come into contact with the liquid L. Then, the oil scraper 27 scrapes up the oil liquid L when the drive shaft 4 rotates, so that the bearing 5, the swivel bearing 11, and the front casing 3 are provided.
The oil liquid L is supplied to the thrust receiving portion 3A, etc., to cool and lubricate them. Reference numeral 28 is a counter weight fixed to the oil scraper 27, and the counter weight 28 balances the rotation of the drive shaft 4.

The scroll type air compressor according to the prior art has the above-mentioned structure, and when the drive shaft 4 is rotationally driven by the electric motor, this rotation is transmitted from the crank 4A to the orbiting scroll 7 via the orbiting bearing 11. .
As a result, the orbiting scroll 7 orbits about the axis of the drive shaft 4 with an orbiting radius of a predetermined dimension d, and by this orbiting movement, outside air is sucked from the suction port 20 through the suction passage 22 to the outermost side. It flows into the compression chamber 19. Then, each compression chamber 19 continuously shrinks, and the air taken in from the suction passage 22 is sequentially sent to the compression chamber 19 on the inner peripheral side to be compressed, while the compressed air is discharged from the discharge port 21 to the external air tank ( (Not shown) and the like to perform a compression action.

[0016]

By the way, in the above-mentioned prior art, since heat of compression is generated in each compression chamber 19 during the compression action, thermal expansion or temperature nonuniformity occurs in each scroll 7, 15. .

On the back surface 8B side of the orbiting scroll 7, cooling is performed by the oil liquid L in the casing 1. At this time, the temperature of the oil liquid L rises due to the heat from each compression chamber 19, and the casing 1 Temperature also rises.

Therefore, unless the fixed scroll 15 and the casing 1 are cooled from the outside, the respective scrolls 7, 1
5 may be thermally deformed or galling may occur in the lap portions 9 and 17.

Therefore, the present inventors provided a cooling duct 29 around the casing 1 and the fixed scroll 15 so as to completely surround them from the outside as in the prior art shown in FIG. By positioning the cooling fan 30 on the drive shaft 4, the cooling air passage 29A is formed between the outer surface of the casing 1 and the cooling duct 29 over the entire circumference, and the cooling air flowing from the fixed scroll 15 side is formed. It was studied to circulate the air around the casing 1 in the cooling duct 29 and let the air flow out from around the drive shaft 4 to the outside.

However, in this prior art, the cooling duct 2
Since the casing 1 and the like are completely surrounded by 9 by the outside, the cooling duct 29 increases the size of the entire apparatus and increases the manufacturing cost. Further, since the total amount of air flowing in the cooling air passage 29A is large, there is an unsolved problem that the fan power becomes excessively large if the wind speed is increased to increase the cooling efficiency.

Further, since cooling air is introduced into the cooling duct 29 from the fixed scroll 15 side and then the periphery of the casing 1 is cooled, this cooling air is warmed when flowing through the fixed scroll 15 side. However, there is an unsolved problem that the low temperature cooling air cannot be circulated around the casing 1 and it is difficult to cool the oil liquid L in the casing 1.

Further, in the prior art, the cooling air is circulated between the casing 1 and the cooling duct 29 so that the casing 1
Since only the outer side surface of the casing 1 is uniformly cooled, the side surface portion of the casing 1 where the oil liquid L is scraped up by the oil scraper 27 cannot be effectively cooled by the cooling air, and the casing 1 There is an unsolved problem that it is difficult to obtain effective lubrication and cooling action with the oil liquid L inside.

The present invention has been made in view of the above-mentioned problems of the prior art. The present invention efficiently cools the casing from the outside by allowing cooling air to flow in from one side of the casing and to flow out from the other side. It is an object of the present invention to provide a scroll type fluid machine capable of improving the reliability.

[0024]

The features of the structure adopted by the present invention to solve the above-mentioned problems are that the casing is provided with an inflow duct for allowing outside air to flow in as cooling air on one outer surface and the other outer surface. An outflow duct that communicates with the inflow duct and outflows the cooling air that has flowed in from the inflow duct is provided on the side surface, and is located between the inflow duct and the outflow duct on the protruding end side of the drive shaft. The purpose is to provide a cooling fan that circulates cooling air from the inflow duct to the outflow duct.

In this case, the outflow duct may be connected to another outflow duct for outflowing the cooling air toward the outer surface of the fixed scroll.

[0026]

With the above structure, the outside air flowing in from the inflow duct becomes cooling air to cool one outer surface of the casing and then flows in the outflow duct to cool the other outer surface of the casing. The flow passage cross-sectional area can be set to the minimum required size, and it is possible to prevent the fan power from becoming excessive due to an excessively large air volume.

Further, since the fixed scroll has a temperature higher than that of the casing, if the cooling air is made to flow from the outflow duct toward the outer surface of the fixed scroll,
The fixed scroll can be cooled after cooling the casing with the cooling air at this time, and the once-cooled cooling air can be prevented from flowing around the casing.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. In the embodiment, the same components as those of the conventional technique shown in FIG. 4 described above are designated by the same reference numerals, and the description thereof will be omitted.

In the figure, 31 indicates a package formed in a substantially rectangular box shape, and the package 31 is formed by joining thin metal plate panels by means such as spot welding.

Reference numeral 32 denotes an air tank provided in the package 31. The air tank 32 is arranged on the bottom plate of the package 31 via a pair of legs 32A and 32A, and will be described later on the air tank 32. Scroll type air compressor 3
A body stand 33 of 5 is provided. The air tank 32 is provided with a discharge pipe 52 of a fixed scroll 37 described later.
The compressed air discharged from the discharge pipe 52 is stored therein.
Further, the main body table 33 has a pair of legs 33A and 33A like the air tank 32, and has a structure in which the scroll air compressor 35 can be stably installed on the air tank 32.

Reference numeral 35 denotes a scroll type air compressor as a scroll type fluid machine. The scroll type air compressor 35 has a casing 36 and a fixed scroll 37 which are substantially the same as the casing 1 and the fixed scroll 15 described in the prior art.
Etc., the casing 36 is provided with a vibration-proof rubber 3 on the main body stand 33.
It is installed via 8 etc. Where the casing 36
On the left and right outer side surfaces of the fixed scroll 37, a plurality of cooling fins 39, 39, ... Also, substantially the same cooling fins 40, 40, ... Are projectingly provided between the suction ports 37B, 37B.

Reference numeral 41 denotes a suction duct as an inflow duct. The suction duct 41 is formed by bending a metal plate or the like into a substantially U shape, and its length dimension is the casing 36.
It corresponds to. The suction duct 41 is attached to the left outer surface of the casing 36 so as to cover each cooling fin 39 located on the left side of the casing 36 from the outside. Here, a flange portion 41A is bent and formed on the downstream end side of the suction duct 41, and the flange portion 41A connects the suction duct 41 to a connection port 44 of a collecting duct 43 described later.
It is connected to A.

Reference numeral 42 denotes an upper duct as another inflow duct, and the upper duct 42 is formed by bending a metal plate into a substantially U-shape like the suction duct 41,
It is attached to the casing 36 so as to cover the central portion of the upper side surface of the casing 36. The downstream end side of the upper duct 42 is bent in an L shape at the rear side of the casing 36, and is connected to the connection port 45B of the collecting duct 43 described below from above.

Reference numeral 43 denotes a collecting duct which is attached to the end face of the casing 36 on the base end side and is located on the left side. The collecting duct 43 has a horizontally long quadrangular front panel 44 and the front panel, as shown in FIG. It is formed in a flat box-like shape including a rear case 45 that abuts against the rear side of 44.

Here, a rectangular connecting port 44A connected to the suction duct 41 is bored on the left end side of the front panel 44, and a bearing portion (not shown) of the casing 36 is provided on the right side of the connecting port 44A. A circular bearing fitting hole 44B that fits in the hole is bored. The front panel 44 has a connection port 4
4A and the bearing fitting hole 44B, a plurality of screw insertion holes 44C, 44C, ... For fixing the front panel 44 to the base end side end surface of the casing 36 are formed, and the front panel 44 is formed. Mounting brackets 44D, 44D, ... Are provided on both upper and lower ends of the.

On the other hand, on the rear side surface of the rear case 45, a cooling air flow hole 45A is formed at a position facing the bearing fitting hole 44B of the front panel 44, and a scroll type air flow hole 45A is provided in the cooling air flow hole 45A. The drive shaft 4 of the air compressor 35 is arranged. Further, the rear case 45 has a connection port 45B formed on the upper side surface to be connected to the upper duct 42, and a mounting bracket 45C (for mounting the rear case 45 to the casing 36 and a fan cover 48 described later ( Only one is shown in FIG. 2), and 45D, 45D, ...

Then, the front panel 44 and the rear case 45
Is attached to each of the mounting brackets 44D and 45D and screwed to the casing 36.

Reference numeral 46 denotes a cooling fan provided on the drive shaft 4. The cooling fan 46 is fitted and fixed to the drive shaft 4, and has rotating blades 47 which rotate integrally with the cooling fan 46 and a fan cover 48 which covers the rotating blades 47. It consists of and. Here, as shown in FIG. 2, the fan cover 48 has a tubular portion 48A and a bottom portion 48B, and the tubular portion 48A is provided with mounting brackets 48C, 48C protruding in the vertical radial direction from the front end side. . The fan cover 48 is formed with a ventilation passage 48D extending tangentially from the side surface of the upper right portion of the cylindrical portion 48A.

Further, the drive shaft 4 is provided at the substantially center of the bottom portion 48B.
Is formed with a shaft insertion hole 48E. Then, the fan cover 48 is airtightly abutted against the rear side surface of the collecting duct 43, and the rotary blades 4 are inserted in the fan cover 48.
When 7 rotates, the air in the collecting duct 43 is sucked into the cylindrical portion 48A and is blown out from the air passage 48D.

Reference numeral 49 denotes a joint pipe for connecting the cooling fan 46 to an outlet duct 50 which will be described later. One end of the joint pipe 49 is a square tubular inlet portion 49A connected to the blow passage 48D of the fan cover 48. The other end side is an outlet portion 49C which projects downward so as to enlarge the flow passage area and has a flange portion 49B formed on the periphery thereof.

Reference numeral 50 denotes an outflow duct attached to the right side surface of the casing 36. The outflow duct 50 is formed by bending a metal plate in substantially the same manner as the suction duct 41, and its length dimension is the length of the casing 36. The length is formed by the depth (length) dimension of the collecting duct 43 rather than the length dimension.

Here, the outflow duct 50 is the casing 36.
Is mounted on the right outer side surface of the cooling duct so as to cover the cooling fins 39, 39, ..., The rear end side of the outflow duct 50 abuts against the right side surface of the collecting duct 43 to be shielded from the outside air, and By abutting the flange portion 50A with the flange portion 49B, the flange portion 49B communicates with the suction duct 41 side.

Reference numeral 51 denotes an L-shaped duct constituting another outflow duct, and the L-shaped duct 51 is the outflow duct 50.
Connected to the cylindrical portion 37C of the fixed scroll 37 and extending in parallel with the cylindrical portion 37C of the fixed scroll 37, and a length that bends at a right angle from the inlet side duct portion 51A and extends along the back surface 37A of the fixed scroll 37. Exit side duct section 51
It is composed of B and. Here, the outlet side duct portion 5
On the fixed scroll side of 1B, a window portion 51C is formed so that each cooling fin 40 of the fixed scroll 37 projects inside the outlet side duct portion 51B, and the outlet side duct portion 51B faces the window portion 51C. An insertion hole 51D of the discharge pipe 52 connected to the discharge port is formed on the front surface of the. Then, on the outlet side duct portion 51B, the rear surface 37A of the fixed scroll 37 is attached to the mounting brackets 51E and 51E provided above and below the window portion 51C via screws (not shown).
Installed on.

Reference numeral 53 denotes a motor support base which is located on the upper duct 42 and is provided on the casing 36 via support legs 53A, 53A, ..., 54 denotes an electric motor provided on the motor support base 53, The electric motor 54 is fixed on the motor support base 53 via a pair of motor legs 54A, 54A, and rotationally drives the output shaft 54B by external power supply.

55 is a large-diameter pulley fixed to the output shaft 54B, and 56 is a small-diameter pulley fixed to the drive shaft 4 of the scroll air compressor 35. The small-diameter pulley 56 is a large-diameter pulley via a belt 57. 55 connected to the electric motor 5
The drive shaft 4 is rotationally driven by the four output shafts 54B.

The scroll type air compressor according to this embodiment has the above-mentioned structure, and its operation will be described below.

First, the drive shaft 4 is driven by the output shaft 54B of the electric motor 54 via the pulleys 55, 56 and the belt 57.
When is driven to rotate, the orbiting scroll is driven in the casing 36, and a compression operation for compressing air with the fixed scroll 37 is performed. And compressed air is air pipe 3
4 is temporarily stored in the air tank 32 and is used for an external pneumatic device or the like. Further, due to this compression operation, heat of compression is generated between the fixed scroll 37 and the orbiting scroll, the fixed scroll 37 side becomes a high temperature state, and the temperature of the oil liquid L in the casing 36 also rises.

However, in this embodiment, the left and right outer surfaces of the casing 36 are provided with a plurality of cooling fins 39, 39, ... And the rear surface 37A of the fixed scroll 37 is provided with a plurality of cooling fins 40, 40 ,. , Further casing 3
6 includes a suction duct 41 that covers the cooling fins 39 on the left outer surface, and an upper duct 4 that covers the upper portion of the casing 36.
2 and the suction duct 41 and the upper duct 42 via a collecting duct 43 or the like, and covers the cooling fins 39, 39, ... On the right outer surface of the casing 36 and the cooling fins 40, 40 ,. 50 and L
The character-shaped duct 51 is provided, and the cooling fan 46 that is rotationally driven by the drive shaft 4 is provided between the collecting duct 43 and the outflow duct 50, so that the following operational effects are achieved.

That is, when the drive shaft 4 is rotated by the electric motor 54 to drive the scroll air compressor 35, the cooling fan 46 is driven together with the drive shaft 4,
At this time, the outside air is sucked into the suction duct 41 and the upper duct 42 in the direction of the arrow A as cooling air, and the casing 3
The left outer surface and the upper outer surface of 6 are cooled and merged in the collecting duct 43, and then flow into the outflow duct 50. And
Since the flow-out area of the outflow duct 50 is smaller than that of the collecting duct 43, at this time, the flow velocity of the cooling air increases,
The casing 3 flows in the direction of the arrow B in the outflow duct 50.
After the right outer side surface of 6 is cooled, it flows in the L-shaped duct 51, cools the back surface 37A of the fixed scroll 37, and is discharged to the outside in the direction of arrow C in FIG.

Here, in the casing 36, as shown in FIG. 3, the oil scraper 27 rotates in the clockwise direction to scrape the oil liquid L in the casing 36 to the left inner surface, and of the scraped oil liquid L. When about 20% of the oil is sprayed and circulated around the upper inner surface of the casing 36, and when the oil scraper 27 subsequently collides with the liquid surface of the oil liquid L, the oil liquid L is splashed toward the right inner surface of the casing 36. In addition, the ratio of the amount of oil scraped up to the left inner surface of the casing 36 and the amount of oil scattered to the right inner surface is about 5: 3.

Therefore, by providing the suction duct 41 along the left outer surface of the casing 36, the suction duct 4
A low-temperature cooling air can be made to flow from 1 in the direction of arrow A, and this cooling air causes most of the oil liquid L in the casing 36 to flow to the cooling fins 39 and the like located on the left outer surface of the casing 36. Can be efficiently cooled through.

Since the upper duct 42 is provided between the casing 36 and the electric motor 54, the radiant heat from the electric motor 54 is radiated from the electric motor 54 by the cooling air A flowing in the upper duct 42. Can be prevented.

Further, after the cooling air A from the suction duct 41 and the upper duct 42 is merged in the collecting duct 43, the cooling air A is discharged via the cooling fan 46.
By circulating the cooling air B as the cooling air B in the 0, the flow velocity of the cooling air B in the outflow duct 50 can be effectively increased, and the right outer surface of the casing 36 can be cooled by the cooling air B. Then, by circulating this cooling air B as the cooling air C in the L-shaped duct 51, the rear surface 3 of the fixed scroll 37 is
The 7A side can be effectively cooled via each cooling fin 40. In this case, since the fixed scroll 37 is in a high temperature state due to the compression heat of air, a sufficient cooling action can be obtained even by the cooling air C after cooling the casing 36.

Therefore, in this embodiment, the outside air is introduced as the cooling air A from the suction duct 41 provided on the left outer surface of the casing 36 to cool the left outer surface of the casing 36, and then the cooling fan 46 and the like are used. This cooling air can be circulated into the outflow duct 50 to cool the right side surface of the casing 36, and the suction duct 41, the outflow duct 50, etc. can prevent the flow area of the cooling air from becoming excessively large. The flow velocity of the cooling air can be increased as much as possible, and it is possible to effectively prevent an excessive rotational torque from acting on the cooling fan 46.

Since the casing 36 side is cooled by the cooling air B before the back side of the fixed scroll 37 is cooled, the oil liquid L in the casing 36 is efficiently cooled by the cooling air in advance. After that, the fixed scroll 37 in the high temperature state can be cooled by the cooling air.

Further, in this embodiment, in order to effectively cool the left side, the right side and the upper side surface of the casing 36, the suction duct 41, the upper duct 42 and the outflow duct 50 are respectively provided on the left side, the right side and the upper side surface of the casing 36. Is provided
Since the cooling air is circulated, it is not necessary to completely cover the entire scroll-type air compressor with ducts from the outside, and the overall size of the device can be reduced, and the ducts 41, 43, 50, 51 can be reduced. Etc. can be formed by a simple process such as press molding, and cost reduction can be achieved.

In the above-described embodiment, the two inlet ducts 41 and the upper duct 42 are provided as inflow ducts, but the present invention is not limited to this. For example, the upper duct 42 may be omitted and the casing may be omitted. It is also possible to form a space between the motor 36 and the electric motor 54 via each support leg 53A of the motor support base 53.

Further, although the scroll type air compressor has been described as an example in the above embodiment, the present invention is not limited to this, and may be used for a scroll type vacuum pump or the like.

[0059]

As described in detail above, according to the present invention, an inflow duct for introducing outside air as cooling air is provided on one outer surface of the casing, and the other outer surface communicates with the inflow duct. Since the outflow duct for outflowing the cooling air from the inflow duct is provided, after cooling one outer surface of the casing by using the outside air flowing in from the inflow duct as the cooling air,
By circulating this cooling air in the outflow duct, the other outer surface can be cooled, the flow passage cross-sectional area of each duct can be reduced, and the amount of cooling air can be prevented from increasing excessively, and the fan power can be reliably reduced. .

Further, if the cooling air is made to flow from the outflow duct toward the outer side surface of the fixed scroll, the fixed scroll can be cooled by using the cooling air after cooling the casing, and the cooling air is effectively used. By utilizing this for various purposes, the fixed scroll and the casing can be efficiently cooled, and various effects such as reliability and durability can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a scroll type air compressor according to an embodiment of the present invention housed in a package.

FIG. 2 is an exploded perspective view showing a fixed scroll, a casing, each duct and the like in FIG.

FIG. 3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is a vertical cross-sectional view showing a scroll type air compressor according to the prior art.

FIG. 5 is a longitudinal sectional view showing a scroll type air compressor provided with a cooling duct according to the prior art.

[Explanation of symbols]

 4 Drive Shaft 4A Crank 7 Orbiting Scroll 19 Compression Chamber 36 Casing 37 Fixed Scroll 39, 40 Cooling Fin 41 Suction Duct (Inflow Duct) 42 Upper Duct (Inflow Duct) 46 Cooling Fan 47 Rotating Blade 48 Fan Cover 50 Outflow Duct 51 L-Shape Mold duct (outflow duct) 54 Electric motor

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display area F04C 29/04 E 6907-3H

Claims (2)

[Claims] 1. A cylindrical casing, a drive shaft having a tip end side rotatably provided in the casing and a base end side protruding outside the casing, and an orbiting scroll provided on the tip end side of the drive shaft. A scroll type fluid machine comprising a fixed scroll facing the orbiting scroll so as to close the tip side of the casing, and a fixed scroll defining a plurality of compression chambers between the orbiting scroll and the casing. An inflow duct that allows outside air to flow in as cooling air is provided on one outer surface, and an outflow duct that communicates with the inflow duct and that allows the cooling air that has flowed in from the inflow duct to flow out is provided on the other outer surface. A cooling fan, which is located between the inflow duct and the outflow duct and circulates cooling air from the inflow duct to the outflow duct, is provided on the protruding end side. Scroll type fluid machine. 2. The scroll type fluid machine according to claim 1, wherein the outflow duct is connected to another outflow duct for outflowing cooling air toward the outer surface of the fixed scroll.