JP2002295383A - Screw compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a screw compressor having an oil tank for uniformly circulating lubricating oil. SOLUTION: The screw compressor 1 has a lubricating oil circulation system comprising a feed passage for feeding the lubricating oil stored in the oil tank 10 to parts which must be fed with lubricating oil such as a timing gear 55, speed increasing gears 71 and 72, a bearing 57 of a rotor shaft, etc., and a collection passage for collecting the fed lubricating oil to the oil tank 10. Partitions 12 and 12 having an opening 13 located close to one end 10a of the oil tank 10 are disposed in the oil tank 10, the inside the oil tank is partitioned into a plurality of chambers 101, 102 and 103, a suction port 22 of the oil feed flow passage is opened in one chamber 102 close to the other end 10b of the oil tank 10, and discharge ports of the collection circuit are opened in the other chambers 101 and 103.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw compressor, and more particularly to a structure of an oil tank provided in a lubricating oil circulation system in an oil-free screw compressor or an oil-free screw vacuum pump, and compression of a speed increasing gear to a casing. The present invention relates to a screw compressor characterized by the mounting of the machine body and the mounting position and mounting method of an oil pump provided in the lubricating oil circulation system.

[0002]

2. Description of the Related Art A screw compressor for compressing fluid by meshing rotation of a pair of male and female screw rotors housed in a cylinder transmits the rotation of a drive source such as a motor to male and female rotors at an increased speed. Speed gear for controlling the rotation timing of the two rotors,
A bearing or the like for supporting the rotor shaft of each rotor is provided, and a lubricating oil circulation system for lubricating these components with lubricating oil is provided.

The lubricating oil circulation system includes an oil tank for storing the lubricating oil, and a lubricating oil stored in the oil tank, which is supplied to the lubricating oil through an oil pump. The lubricating unit includes a lubrication unit that supplies lubricating oil supplied to the lubricated unit and lubricates each unit to an oil tank.

[0004] As an example, two compressor bodies comprising a high pressure stage and a low pressure stage are provided, and the compressed fluid obtained in the low pressure stage compressor body is introduced into the high pressure stage compressor body and further compressed. The screw compressor shown in FIGS. 7 to 9 configured to obtain a high-pressure compressed fluid will be described with reference to a compressor body 50 of a low-pressure stage. On the discharge side, the oil supply nozzles 31 arranged in the gear chamber 56 of the timing gear 55 and the casing 73 of the speed increasing gears 71 and 72 are connected, and the oil supply passages 58a and 58a communicate with the bearings 57.
An oil supply means for connecting the lubricating oil in the oil tank 10 to each lubricated portion is formed.

[0005] Below the bearing 57 that supports the rotor shaft 52 on the discharge side, there is formed an oil discharge passage 59b whose upper end is opened in contact with the bearing 57 and whose lower end is opened in the gear chamber 56 of the timing gear 55. The gear chamber 56 of the timing gear 55 communicates with the oil tank 10 through an oil drain pipe 80.

Further, below a bearing 57 which supports the rotor shaft 51 on the intake side, an oil drain passage having an upper end opened in contact with the bearing 57 and a lower end opened to a casing 73 of the speed increasing gears 71, 72. 59a are formed, and each of these flow paths 5
9a, 59b, oil drain pipe 80, casing 73 of speed increasing gear
Form a collecting means for collecting the lubricating oil in the oil tank.

[0007] In the lubricating oil circulation system configured as described above, the drive source 85 such as a motor is started to start the compressor body 5.
When the rotation of 0, 60 is started, the lubricating oil in the oil tank 10 is pumped up by the oil pump 20 which starts with the rotation of the speed increasing gears 71, 72, and the lubricating oil is supplied to the lubricated portion and discharged. The lubricating oil that lubricates the bearing 57 that supports the rotor shaft 51 on the side is introduced into the gear chamber 56 of the timing gear 55 via the oil drain passage 59b, and the lubrication oil injected into the gear chamber 56 by the oil supply nozzle 31. The oil merges with the oil and is collected in the oil tank 10 via the oil drain pipe 80.

The lubricating oil supplied to the bearing 57 that supports the suction-side rotor shaft 51 is supplied to the inside of the casing 73 of the speed increasing gears 71 and 72 via the oil discharge passage 59a and from the oil supply nozzle 31. The lubricating oil injected into the high-speed gears 71 and 72 drops in the casing 73 of the high-speed gears and collects in the oil tank 10 as droplets or the like accompanying the rotation of the high-speed gears 71 and 72, and so on. The work is repeated and circulated.

[0009]

In the lubricating oil circulating system of the screw compressor constructed as described above, the oil tank 10 for storing the lubricating oil is provided in the casing 7 of the speed increaser 70.
3 is provided as a space integrally formed below, and a speed increasing gear which is pumped up by an oil pump 20 through a suction port 22 opened at one end of the oil tank 10 and needs to supply lubricating oil. The lubricating oil collected on the oil surface near the suction port 22 in the oil tank 10 is relatively short because it is configured to be supplied to each part such as 71, 72, the timing gear 55, the bearing 57, and the like. While the lubricating oil is sucked up from the suction port 22 and supplied to the lubricated portion in a time, the lubricating oil collected on the oil surface far from the suction port 22 is compared with the lubricating oil collected on the oil surface near the suction port 22, It takes a relatively long time after being collected to be sucked up again from the suction port 22.

As described above, if the time from when the oil is collected in the oil tank 10 to when it is circulated again is short, the number of circulations of the lubricating oil increases and the oil tends to deteriorate. If the time until suction is long and the time of staying in the oil tank 10 is long, the number of circulations is small and deterioration is difficult.

Therefore, when the oil tank 10 having the above-described integral structure is used, the oil tank 1
In the range of 0, the lubricating oil is divided into a portion where the lubricating oil stays and is not circulated, and a portion where the lubricating oil is recirculated relatively early.

The lubricating oil deteriorated in this way has a low viscosity, and an oil film is less likely to be formed on the surface of the lubricated part.
1, 72, when lubricating the timing gear 55,
Poor lubrication may cause uneven wear and seizure of gears and bearings. Therefore, it is necessary to replace the deteriorated lubricating oil with a new lubricating oil. However, as described above, usable oil that has not been deteriorated remains in the oil tank 10. Replacing all lubricants, including oil, is uneconomical. In addition, the frequency of replacing the lubricating oil increases due to the partial deterioration of the lubricating oil, and this replacing operation is complicated.

In a conventional screw compressor,
The gear 23 fixed to the input shaft 21 of the oil pump is configured to mesh with a drive gear 75 arranged coaxially with the drive-side speed increasing gear 71 to drive the oil pump 20 (FIGS. 8 and 9). 9), the gear 2 of the oil pump 20
3 and a configuration for supplying lubricating oil to the meshing portion with the drive gear 75 (for example, the oil supply nozzle 31 in FIG. 8)
Must be provided in the lubricating oil circulation system described above, which complicates the configuration.

Further, the arrangement position of the compressor bodies 50 and 60 is restricted by the arrangement of the oil pump 20, so that the casing 73 of the speed increasing device 70 is enlarged.

Further, in the conventional screw compressor 1, since the casing 40 on the suction side of the compressor main bodies 50 and 60 is arranged in the casing 73 of the speed increasing device 70, the mating surface is provided. There is a problem that the size of the casing 73 of the speed increasing device 70 is increased due to an increase in size.

Therefore, the present invention has been made to solve the above-mentioned drawbacks in the prior art, and eliminates the lubricating oil staying in the oil tank, and allows the lubricating oil in the oil tank to circulate evenly, thereby improving lubrication. The oil exchange cycle can be extended, and the arrangement of the compressor body and the oil pump, and the mounting structure are suitable for reducing the size of the gearbox casing, thereby reducing the size of the gearbox casing. Accordingly, it is an object of the present invention to provide a screw compressor that can be reduced in size and weight as a whole.

[0017]

In order to achieve the above object, a screw compressor according to the present invention comprises a timing gear 55 for regulating the rotation timing of male and female rotors, and a power from a drive source 85 such as a motor. Gears 71, 72 for increasing the speed and transmitting the same to the rotor shaft 51 of the rotor, and supplying lubricating oil to lubricated parts including the timing gear 55 and the speed increasing gears 71, 72, In the screw compressor 1 provided with a lubricating oil circulation system that collects the lubricating oil supplied to the lubricating oil and supplies the lubricating oil to the lubricated portion again, the lubricating oil circulation system is provided in the casing 73 of the speed increasing gears 71 and 72. Oil tank 10 formed as a space continuous with the oil tank 10, a pipe for supplying the lubricating oil stored in the oil tank 10 to the lubricated portion via the oil pump 20, and an oil supply passage 58.
a, 58b, an oil supply means comprising an oil supply nozzle 31 and the like, and an oil drain pipe 8 for collecting at least the lubricating oil which has lubricated the timing gear 55 among the lubricated parts into the oil tank.
And a partition plate 1 for dividing the inside of the oil tank 10 into a plurality of chambers 101, 102, 103.
2, 12 are provided, and one end 12a,
A communication passage 13 is provided near the chamber 12a and communicates between the chambers 101, 102 and 103, and the partition plate 1
A suction port 2 for introducing lubricating oil to the oil supply means in the one chamber 102, which is located near the other ends 12 b of the second and second 12.
2, and a discharge port 81 for discharging the lubricating oil recovered by the recovery means is opened in the other chambers 101 and 103 (claim 1).

In the screw compressor 1 having the above configuration,
The communication passage 13 communicating between the chambers 101, 102, 103 in the oil tank 10 can be formed by openings formed in the partition plates 12, 12.

Further, one chamber 102 of the oil tank in which the suction port 22 is opened, and the speed increasing gears 71, 7
It is preferable to dispose a shielding plate 14 for blocking communication between the two spaces between the two casings 73 (claim 3).

Each of the chambers 101, 10 formed by dividing the inside of the oil tank 10 by the partition plates 12, 12 is formed.
The baffle plate 15 may be provided on each of the partition plates 2 and 103 in a direction perpendicular to the partition plates 12 and 12 in plan view.

The speed-increasing gear includes a drive-side speed-increasing gear 71 attached to a drive source 85 such as a motor, and one of the rotor shafts of the compressor bodies 50 and 60 (a male rotor in FIG. 1). A shaft 54), a driven side speed increasing gear 72, and a flange 54 formed on a bearing cover 53 that locks a bearing 57 of the rotor shaft 51 to which the driven side speed increasing gear 72 is mounted in a shaft hole; When mounting the bearing cover 53,
The flange 54 forms a stepped portion protruding from the casing outer wall of the compressor body 50, and an opening 74 having a size corresponding to the flange 54 of the bearing cover 53 is formed in the side wall of the casing 73 of the speed increasing gears 71 and 72. , The opening 74
Through one end of the rotor shaft 51 and the driven side speed increasing gear 7
2 is inserted into the casing 73 of the speed increasing device 70 and the flange 54 of the bearing cover 53 is
The cover 74 covers the opening 74 by inserting into the inside (claim 5).

The input shaft of the oil pump 20 is
The input shaft 21 of the oil pump 20 and the rotary shaft 76 of the drive-side speed increasing gear 71 may be connected to be arranged coaxially with the rotation shaft 76 of the drive-side speed increasing gear 71 (claim 6). ).

In the above configuration, the drive-side speed increasing gear 7
1, the input shaft 21 of the oil pump 20 and the rotating shaft 76 of the drive-side speed increasing gear 71 can be connected via a spline via the coupling 24. .

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described below with reference to the accompanying drawings.

In the screw compressor 1 of the present invention, the point that the lubricating oil circulation system includes the oil tank 10 and that the oil pump 20 pumps the lubricating oil stored in the oil tank 10 is provided. The lubricating oil pumped to the lubricating part by the oil supply means for supplying the lubricating oil and the recovery means for returning the lubricating oil lubricating each lubricated part to the oil tank 10 are provided as described above. This is the same as the lubricating oil circulation system in the conventional screw compressor 1 described above.

The screw compressor 1 shown in FIG. 1 has two compressor main bodies 50 and 60 including a high-pressure stage and a low-pressure stage (see FIG. 2), and is obtained in the compressor main body 50 in the low-pressure stage. It is the same as the screw compressor 1 described as the related art in that the compressed fluid is introduced into the compressor main body 60 in the high-pressure stage and further compressed to obtain a high-pressure compressed fluid. However, the screw compressor to which the present invention is applied is not limited to the one having the two compressor bodies 50 and 60 as shown in FIG. 1, but the one having only a single compressor body. May be.

The screw compressor 1 configured as described above
In the above, the driven-side speed increasing gear 72 provided on one of the suction side rotor shafts of the compressor bodies 50 and 60 (the rotor shaft 51 of the male rotor in the present embodiment) is provided inside the casing 73 of the speed increasing gear. A timing gear 55 that regulates the rotation timing of the rotor shaft of the male rotor and the rotor shaft of the female rotor is fixed to the discharge-side rotor shaft 52 of each compressor body, while being engaged with the drive-side speed increasing gear 71.
A gear chamber 56 for accommodating the timing gear 55 is formed by being attached to casings of the compressor main bodies 50 and 60.

Further, lubricating oil passages 58a, 58 for supplying lubricating oil to the bearings 57 are provided in the bearings 57 of the respective rotor shafts.
8b and oil drain passages 59a and 59b for discharging the lubricating oil that has lubricated the bearing 57. Of these oil supply passages 58a and 58b, a pipe connected to the oil pump 20 is connected to an oil cooler. 90, an oil filter 100, etc., to make it possible to supply the lubricating oil in the oil tank 10, and to communicate the oil drain passages 59a, 59b to the oil tank 10 to lubricate the bearing 57. It is configured so that it can be collected in the oil tank 10.

In the present embodiment, the lower end of the oil discharge passage 59a connected to the bearing 57 of the rotor shaft 51 on the suction side is opened in the casing 73 of the speed increasing gear. The lubricating oil that has passed through 59a falls down in casing 73 and is introduced into oil tank 10.

The oil discharge passage 59b communicated with the bearing 57 of the discharge-side rotor shaft 52 is connected to the timing gear 55.
The oil tank 1 is opened together with the lubricating oil that lubricates the timing gear 55 through an oil drain pipe 80 that communicates between the gear chamber 56 and the oil tank 10.
It is configured to be collected within zero.

[Oil Tank] In the oil tank 10 provided in the lubricating oil circulation system formed as described above, the lubricating oil recovered by lubricating each lubricated portion is stored in the oil tank 1.
Regardless of the position where the oil is collected, the oil recovery system is provided with a structure in which the collected oil can be suitably circulated so as to be uniformly mixed in the oil tank 10.

In this embodiment, the oil tank 1
0 is one end (right end in FIG. 1) 10 as shown in FIG.
a, the upper opening 11 is connected to the lower end of the casing 73 of the speed increasing device 70 to form a space integrated with the space in the casing 73 of the speed increasing device 70. And a plurality of chambers 101, 102, 1 inside the oil tank 10 as shown in FIG.
03 is provided with the partition plates 12
The other end 10 of oil tank 10 defined by 2 and 12
The lubricating oil suction port 22 communicating with the oil pump 20 is opened in at least one chamber 102 located closer to b, and an oil drain pipe communicating with the gear chamber 56 of the timing gear 55 in the other chambers 101 and 103. The discharge port 81 of 80 is opened, and the lubricating oil supplied to the lubricated portion is collected in the oil tank 10 (see FIGS. 1 to 3).

In the embodiment shown in FIG. 1, the partition plates 12, 12 are located near one end 10a of the oil tank 10.
Is formed to form a communication passage 13 that communicates between the chambers 101, 102, and 103. This communication passage 13 may be formed by a cutout formed in the partition plate 12,
Further, the partition plate 12 is disposed on the one end 10a side of the oil tank 10 so as to be separated from the inner wall of the tank.
A communication path 13 that communicates between 02 and 103 may be formed, and the configuration is not limited to the configuration shown in FIG.

Preferably, the oil drain 8 communicates between the gear chamber 56 of the timing gear 55 and the oil tank 10.
0, 80 'is arranged near the other end 10b of the oil tank 10 and opened in the other chambers 101, 103, and the lubricating oil introduced into the oil tank 10 through the oil drain pipe 80 is as much as possible. The suction port 22 and the discharge ports 81, 8 of the oil drain pipes 80, 80 'so that they can be sucked up from the suction port over a long distance.
1 'and the arrangement position of the communication passage 13 are determined.

In the present embodiment, as shown in FIG. 3, two oil plates having the same length direction as the rotation axis of the rotor shafts of the compressor bodies 50 and 60 in the oil tank 10 are provided. Partition plates 12 and 12 are provided, and the inside of the oil tank 10 is divided into three chambers 101, 102 and 103, and the partition plate 1
A suction port 22 communicating with the oil pump 20 is opened in the central chamber 102 formed between
One of the chambers 101, 103 is provided with a discharge port 81 of an oil drain pipe 80 communicating with the timing gear chamber 56 of the compressor body 50 of the low pressure stage, and the remaining chamber 103 is provided with a timing gear of the compressor body 60 of the high pressure stage. The discharge port 81 'of the oil drain pipe 80' communicating with the chamber is opened (see FIG. 2).

Preferably, the upper opening 11 of the oil tank 10, which communicates with the space in the casing 73 of the speed increasing device 70, forms a shielding plate at the center of the chamber 102 as shown in FIG. 14, the speed increasing device 70
The lubricating oil that has flowed down inside the casing 73 is not directly introduced into the central chamber 102 formed in the oil tank 10 but is introduced into the other two chambers 101 and 103.

With this configuration, the lubricating oil that has flowed down in the casing 73 of the speed increasing device 70 is not directly introduced into the central chamber 102, and the oil drain pipes 80, 8
Chambers 101, 10 having discharge openings 81, 81 'of 0' opened
3 and is mixed with the lubricating oil recovered through the oil drain pipes 80 and 80 'and introduced into the central chamber 102.
It is possible to prevent adverse effects such as early deterioration of a part of the collected lubricating oil.

The interior of the oil tank 10 is divided into chambers 101,
As shown in FIG. 6, baffle plates 15, which are perpendicular to the partition plates 12, 12 in plan view, are provided on the partition plates 12, 12 divided into 102 and 103 and the inner wall of the oil tank 10. The lubricating oil flowing in the tank 10 is caused to collide with the baffle plate 15 so that the oil in the oil tank 10 is more evenly mixed.

As shown in FIG. 5, the baffle plate 15 is opposed to two opposing
The wall is formed so as to alternately protrude from one of the two wall surfaces toward the other, so that when the lubricating oil circulates in each of the chambers 101, 102, and 103, the lubricating oil collides with the baffle plate 15 to generate a meandering flow of the lubricating oil. Then, the lubricating oil is agitated during the meandering, and the deteriorated lubricating oil and the undeteriorated lubricating oil are evenly mixed.

The oil tank 10 configured as described above
, The timing gear 55 and the rotor shaft 52 on the discharge side.
The lubricating oil that has lubricated the bearing 57 is recovered into the oil tank 10 through oil drain pipes 80 and 80 ′ communicating with the gear chamber 56 of the timing gear 55, and the speed increasing gears 71 and 72.
The lubricating oil that has lubricated the bearing 57 of the suction side rotor shaft 51 flows down in the casing 73 of the speed increasing device 70 and is introduced into the oil tank 10.

As described above, the oil tank 10 is
A plurality of chambers 101, 1 formed by being divided by 2, 12
Of the chambers 02 and 103, the chamber 102 in which the suction port 22 communicating with the oil pump 20 is opened is partitioned from the chambers 101 and 103 into which the return lubricating oil lubricating the above-described respective parts is introduced. When lubricating oil is sucked up by the oil pump 20 through the suction port 22, the other chambers 101, 10
The return lubricating oil recovered in 3 is introduced into the chamber 102 having the suction port 22 opened through the communication passage 13, and the lubricating oil along the length direction of the partition plates 12, 12 in the oil tank 10. Flow occurs.

As described above, the inside of the oil tank 10 is partitioned by the partition plates 12, 12, and the suction port 22 communicating with the oil pump 20 and the opening position of the oil drain pipe 80 are defined by the convection of the lubricating oil in the oil tank 10. By arranging the lubricating oil to be generated, it is possible to prevent the lubricating oil from being mixed evenly in the oil tank 10, and to prevent inconveniences such as partially deteriorating the lubricating oil and shortening the lubricating oil replacement cycle. .

[Attachment Structure of Compressor Body and Oil Pump] In the lubricating oil circulation system of the present invention, the casing 73 of the speed increasing device 70 is further reduced in size, and the structure of the lubricating oil circulation system is further reduced. In order to simplify the above, the screw compressor 1 described as the prior art has a structure in which the suction side casing 40 of the compressor bodies 50 and 60 is inserted into the casing 73 of the speed increasing device 70. 7 (see FIG. 7), the casing 40 on the suction side of the compressor bodies 50 and 60 is arranged outside the casing 73 of the speed increasing device 70, and the bearing cover 53 for sealing the shaft hole on the suction side.
When the shaft hole is sealed by the bearing cover 53, the flange 54 protrudes from the outer wall surface of the suction side casing 40 to form a step, and the speed increasing device 70
By fitting the flange 54 into an opening 74 formed on the side surface of the casing 73, the opening 74 of the casing 73 is covered.

In the conventional screw compressor 1, the drive gear 7 provided coaxially with the drive-side speed increasing gear 71.
5, the gear 23 attached to the input shaft 21 of the oil pump 20 meshes with the gear 23 to drive the oil pump 20 (see FIGS. 8 and 9). The input shaft 21 of the pump 20 is directly connected to the rotating shaft 76 of the drive-side speed-up gear 71, and the axis of the drive-side speed-up gear 71 and the axis of the input shaft 21 of the oil pump 20 are arranged on the same line. I have.

As described above, by disposing the suction-side casings of the compressor bodies 50 and 60 outside the casing 73 of the speed increasing device 70, the speed increasing device 70 is downsized, and the screw compressor 1 is downsized as a whole. By reducing the weight, and by arranging the bearings on the suction side of the compressor bodies 50 and 60 outside the casing 73 of the speed increasing device 70, the maintainability of this portion is improved.

In the conventional arrangement of the oil pump 20, the axis of the drive-side speed increasing gear 71 and the oil pump 20
It is necessary to arrange the shaft center of the input shaft 21 in a stepped manner, and the arrangement position of the compressor bodies 50 and 60 is restricted by such an arrangement of the oil pump 20, and the compressor body 60 of the high-pressure stage is Although the compressor body 50 of the low-pressure stage had to be arranged at a substantially horizontal position as shown in FIG. 8, the oil pump 20 was directly connected to the rotating shaft 76 of the drive-side speed increasing gear 71, so that the oil pump The restriction on the arrangement positions of the low-pressure stage compressor main body 50 and the high-pressure stage compressor main body 60 due to 20 is relaxed, and the height positions can be shifted vertically as shown in FIG. As a result, the entire size of the screw compressor 1 can be reduced, and it is not necessary to provide an oil supply nozzle or the like for lubricating a meshing portion between the gear 23 of the oil pump 20 and the drive gear 75.
The structure of the lubricating oil circulation system can be simplified.

As described above, in order to arrange the suction side casings of the compressor main bodies 50 and 60 outside the casing 73 of the speed increasing device 70, the screw compressor 1 of the present invention requires
A flange 54 is formed in a bearing cover 53 that seals an end of a shaft hole formed in a suction-side casing of the compressor main bodies 50 and 60, and a casing 73 of a speed increasing device 70 has substantially the same size as the flange 54. Are formed, and the flange 54 of the bearing cover 53 is inserted into the opening 74 of the casing 73.

An opening 77 is formed in the side wall of the casing 73 of the speed increasing device 70 at an extension of the oil discharge passage 59a for discharging the lubricating oil lubricating the bearing 57. The lubricating oil discharged through 59a is configured to be introduced into the casing 73 of the speed increasing device 70.

As for the structure of the mounting portion of the oil pump 20, as shown in FIG. 7, the coupling 24 coaxial with the rotating shaft 76 of the driving-side speed increasing gear 71 is provided on the side surface of the driving-side speed increasing gear 71. The input shaft 21 of the oil pump 20 is fixed by a spline via the coupling 24.

With such an oil pump 20 mounting structure, even if the oil pump 20 is removed during maintenance, for example, the drive-side gift gear 7 can be used.
The center of the rotation shaft 76 and the input shaft 21 of the oil pump 20 can be easily aligned.

The supply of the lubricating oil to the spline portion is performed by the lubricating oil supplied to the speed-increasing gears 71 and 72 by the splash generated by the centrifugal force when the driven-side speed-increasing gear 72 rotates. There is no need to separately provide a mechanism for supplying oil to the spline, and the structure of the lubricating oil circulation system can be simplified.

In the present embodiment, the oil pump 20 is attached by a spline via the coupling 24 in the present embodiment.
0 is not limited to this method, and the oil pump 2 is mounted on the axis of the rotating shaft 76 of the drive-side speed increasing gear 71.
Other structures may be used as long as the structure can attach the 0 input shaft 21.

As described above, by arranging the suction side casings of the compressor bodies 50 and 60 outside the casing 73 of the speed increasing device 70, in the conventional screw compressor 1, the compressor bodies 50 and 60 Needs a width to accommodate the suction side casing of the speed increasing device 70.
3 increases the size and weight of the screw compressor 1 as a whole, but this configuration can reduce the thickness of the casing 73 of the speed increasing device 70 to about 、, and The weight of the entire apparatus can be reduced.

As described above, the compressor main bodies 50, 6
0 to the casing 73 of the speed increasing device 70.
The casing 7 of the speed increasing device 70
3, the strength of the casing 73 of the speed increasing device 70 can be maintained even when the arrangement interval of the compressor main body is narrowed, and the compressor main body 50, By arranging the oil pump 20, which restricts the arrangement position of the oil pump 20, on the axis of the drive-side speed increasing gear 71 as described above, the compressor body 50 of the low-pressure stage and the compressor body 60 of the high-pressure stage are reduced. Can be shifted in the height direction, and the size of the gear case 73 can be reduced.

[0055]

According to the structure of the present invention described above, the lubricating oil staying in the oil tank can be eliminated, the lubricating oil in the oil tank can be circulated uniformly, and the arrangement of the compressor body and the oil pump can be reduced. By making the mounting structure suitable for downsizing the casing of the speed increasing gear, it is possible to provide a screw compressor that can reduce the size of the casing of the speed increasing gear, and thus can reduce the overall size and weight. did it.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing a screw compressor according to the present invention.

FIG. 2 is a view taken in the direction of the arrow A in FIG. 1;

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is a sectional view taken along line CC of FIG. 1;

FIG. 5 is a sectional view taken along the line BB of FIG. 1 showing a modified example of the oil tank.

FIG. 6 is an enlarged sectional view of a main part showing a mounting part of the oil pump.

FIG. 7 is a sectional view of a main part of a conventional screw compressor.

FIG. 8 is a sectional view taken along line AA of FIG. 7;

FIG. 9 is a sectional view of a main part of a conventional screw compressor.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Screw compressor 10 Oil tank 10a One end of oil tank 10b The other end of oil tank 11 Opening 12 Partition plate 13 Communication path (opening) 14 Shielding plate 15 Baffle plate 101, 102, 103 Chamber formed in oil tank 101a, 102a, 103a One end of each chamber 101b, 102b, 103b The other end of each chamber 20 Oil pump 21 Input shaft 22 Suction port 23 Gear 24 Coupling 30 Supply channel 31 Oil supply nozzle 40 Suction side casing 50 Compressor body (low pressure stage) 51 Rotor shaft (suction side) 52 Rotor shaft (discharge side) 53 Bearing cover 54 Flange (of bearing cover) 55 Timing gear 56 Gear chamber (of timing gear) 57 Bearing (of rotor shaft) 58a, 58b Oil supply channel 59a, 59b Oil drain passage 60 Compressor body (high pressure stage) 61 Rotor Shaft (suction side) 70 Speed increasing device 71 Drive side speed increasing gear 72 Driven side speed increasing gear 73 Casing 74 Opening (for inserting rotor shaft) 75 Drive gear (for driving oil pump) 76 Rotary shaft (for drive side speed increasing gear) ) 77 Opening 80, 80 ′ Drainage pipe 81, 81 ′ Discharge port 85 Drive source (motor) 90 Oil cooler 100 Oil filter

Continued on the front page F term (reference) 3H029 AA03 AA15 AA24 AB03 BB03 BB32 CC08 CC09 CC17 CC26

Claims (7)

[Claims] 1. A timing gear for regulating the rotation timing of male and female rotors, a speed increasing gear for increasing the power from a drive source and transmitting the power to a rotor shaft of the rotor, the timing gear and the speed increasing gear A lubricating oil is supplied to the lubricated parts including the lubricating part, and the lubricating oil supplied to each of the lubricated parts is collected and supplied to the lubricated part again. A circulating system, an oil tank formed as a continuous space in the casing of the speed increasing gear, an oil supply means for supplying a lubricating oil stored in the oil tank to a portion to be lubricated via an oil pump, Of the parts to be lubricated,
A collecting means for collecting at least the lubricating oil lubricating the timing gear into the oil tank, a partition plate for dividing the inside of the oil tank into a plurality of chambers, and the chamber positioned near one end of the partition plate. A communication passage is formed to communicate the space therebetween, and a suction port for introducing lubricating oil to the lubricating means is opened in the one chamber located near the other end of the partition plate, and the recovery is performed in another chamber. A screw compressor characterized in that a discharge port for discharging the lubricating oil collected through the means is opened. 2. The screw compressor according to claim 1, wherein the communication path is an opening formed in a partition plate. 3. A shielding plate for blocking communication between the two spaces between one chamber of the oil tank having the suction opening and a casing of the speed increasing gear. 2. The screw compressor according to 2. 4. A baffle plate which is orthogonal to the partition plate in a plan view is provided in each of the chambers formed by dividing the inside of the oil tank by the partition plate. 3. The screw compressor according to claim 1. 5. The speed-up gear comprises a drive-side speed-up gear attached to a drive source and a driven-side speed-up gear attached to one rotor shaft of a compressor body. A flange is formed on a bearing cover that locks a bearing of the rotor shaft having the attached inside the shaft hole, and when the bearing cover is attached, a step portion is formed by the flange to protrude from a casing outer wall of the compressor body. An opening having a size corresponding to the flange of the bearing cover is formed in the casing side wall of the speed increasing gear, and one end of the rotor shaft and the driven side speed increasing gear are inserted into the casing of the speed increasing gear through the opening. The screw compressor according to any one of claims 1 to 4, wherein a flange of the bearing cover is inserted into the opening, and the opening is covered. 6. The speed-up gear comprises a drive-side speed-up gear attached to a drive source and a driven-side speed-up gear attached to one of the rotor shafts of a compressor body. 6. A rotary shaft of the drive-side speed increasing gear is arranged coaxially, and an input shaft of the oil pump and a rotation axis of the drive-side speed increasing gear are connected to each other. The screw compressor according to the item. 7. A coupling is fixed to the driving-side speed increasing gear, and an input shaft of the oil pump and a rotation axis of the driving-side speed increasing gear are connected by a spline via the coupling. The screw compressor according to claim 6, wherein