JPH07111186B2 - Roots blower seal configuration - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to the recovery of generated CO ₂ gas,
Roots-type blower seal structure that is compatible with vacuum blowers used for gas sample collection at nuclear power plants, spent nuclear fuel storage facilities, etc. is extremely useful for air inflow, oil outflow, and oil inflow into the vacuum chamber. It provides a seal structure that exerts a synergistic effect of preventing pollution and develops the field of pollution prevention.

[0002]

2. Description of the Related Art Heretofore, various types of seal structures have been known in a roots type vacuum blower. However, this type of vacuum pump (blower) also uses more SUS material,
Leakage is not allowed in the sealing mechanism, so improvement and improvement are necessary, and cost reduction is also one of the important requirements for development.

[0003]

What should be taken into consideration in the development is (1) the mechanical seal for liquid and the mechanical seal for gas are confused. (2) It is safe to use double dry mechanical seals for gas roots blowers and other blowers. (3) It is safe to use a mechanical seal and an oil seal together. However, in the case of gas, if it is a mechanical seal using oil, the oil management method,
You have to consider your knowledge about inflow and outflow,
Since it is often the case that all consumers do not have that knowledge, it is not possible to have a safe and low-cost configuration like (2) and (3).

The vacuum roots type blower used for CO ₂ gas recovery requires the following performance.

[Equation 1] Even at high speeds and high vacuums that satisfy the above (1) and (2), there should be no troubles of air inflow, oil outflow, and inflow. In addition, in the vacuum blower for sampling of facilities such as nuclear power generation,

[Equation 2] Therefore, the dry performance of the above (1) and (2) is required for the SUS material and the like, and inflow of air, outflow of oil, and inflow are not allowed. In addition, cost reduction is required. An object of the present invention is to develop a seal structure of a roots-type blower corresponding to the above.

[0005]

According to the present invention, 1) the oil bath slinger 21 of the oil bath Z is strengthened. 2)
The atmosphere side mechanical seal assembly B is an oil flow type single mechanical seal. 3) providing a threaded slinger 6 ₄ to the rotor shaft 6. 4) Floating sheet 2 for atmospheric side mechanical seal assembly B
A dry room 31 is provided around the atmosphere side of No. 3. 5) Install the vacuum side dry slinger assembly A on the vacuum side of the bearing 15. Etc.,

A multi-stage or single-stage vacuum roots blower,
In the case where the atmosphere side mechanical seal assembly B is provided, a slinger 21 for forced cooling of the bearing 15 is provided on the atmosphere side of the bearing 15 of the housing L provided with the oil bath Y on the outside, and a dry seal is provided on the vacuum side of the bearing 15. 12 and so as to correspond to a portion of the inner surface of the dry seal 13, and Katahama the sleeve 14 to the bearing insert 6 ₂ of the rotor shaft 6, the vacuum-side dry-type which is constituted by the said sleeve 14 and the dry seal 12 the provided slinger assembly a, the air side the dry seal assembly C comprising a dry seal 29 contacting the inner surface the sleeve 27 and the sleeve fitted on the air side of the floating sheet 23 fixed to the dry seal portion 6 ₅ of the rotor shaft 6
Roots-type blower which is provided with an atmosphere-side dry room 31 on the atmosphere side of the floating sheet 23, and prevents the inflow of air, the outflow of oil, and the inflow of oil into the vacuum chamber by the synergistic effect of the above-mentioned respective parts. The present invention relates to the seal structure.

[0007]

The present invention will be described later in (1) (2) (3) (4) (5) (6)
And by the synergistic effect of (7), it exerts the total effect of the seal of the roots blower. (1) vacuum side dry formula slinger assembly A configured with a dry seal 12, 13, etc. by Katahama the sleeve 14 to the bearing insert 6 ₂ prevents from flowing into the vacuum chamber of the oil, the seal oil Excellent performance to enable. (2) Floating sheet 23 with mechanical seal
Atmosphere side mechanical seal consisting of and seal ring 24
Since it is applied by the assembly B, the overhang of the rotor shaft 6 can be eliminated and the vibration can be reduced. (3) The atmosphere side mechanical seal assembly B
Must be of the oil flow type. Most applicable to the present invention. (4) The oil slinger 21 can be a strong type suitable for keeping the temperature of the sliding surface of the mechanical seal low. (5) to the rotor shaft 6, because provided the threaded slinger 6 ₄ made to correspond to the spring case 26 of the seal ring 24, the oil temperature of the mechanical seal sliding surface can be kept low with the oil slinger 21. (6) The atmosphere-side dry room 31 has a volume sufficient to allow the leak gas to expand, so that the expansion room can be expanded freely. (7) The atmosphere side dry seal assembly C corresponds to the idea that an oil seal is acceptable, and there are various openings according to Table 1 depending on rubber and other mating materials.

[0008]

[Table 1]

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The attached drawings show an embodiment of the present invention.
1 is a vertical sectional front view of a central portion, FIG. 2 is a perspective view of a roots type rotor on a motor drive side, and FIG. 3 is an enlarged vertical sectional view of a part of FIG.
FIG. 4 is an enlarged vertical sectional view of another part of FIG.

FIG. 1 shows a multistage vacuum roots type blower X for collecting CO ₂ gas by the PSA method or collecting gas samples at a nuclear power plant, a spent nuclear fuel storage facility, etc. Two eyebrows type rotors 2 in grain 1
Equipped with. Figure 2 shows the eyebrow type rotor 2 on the drive side by the motor
Are shown, 3-lobe first stage Roots type rotor 3 and the rear stage Roots type rotor 4 becomes coupled from the coupling member ₆₁ of the rotor shaft 6, the first stage casing 7 of the first stage Roots-type rotor 3 outer cereal 1
In matches, videos subsequent Roots rotors 4 downstream casing 8, passed through the connecting portion ₆₁ in the partition wall 9. (Timing gear 4
Although the interlocking side by 1 is omitted in both FIGS. 1 and 2, the dry seal portion 6 ₅ and the pulley connecting portion 6 _{6 which} will be described later are not provided in terms of shape. )

A timing gear case Z ₁ for fixing the housings L, R to the left and right of the outer grain 1, fixing the cover Y ₁ of the oil bathroom Y on the outside of the housing L, and achieving the oil bathroom Z on the outside of the housing R To fix. A shaft hole through which the rotor shaft 6 is inserted is formed in the housing L, the cover Y _1, and the housing R. (Cover Y ₁ is provided with a shaft hole only in a portion through which the driving side of the rotor). The rotor shaft 6 is provided a housing L, bearing insert 6 _2, 6 ₂ shaved slightly outside diameter in each of its outwardly those passing part-length in R, oil portion protruding in an oil bath Y of the housing L side the slinger mounting portion 6 ₃ provided, the drive-side only cover Y ₁ threaded slinger 6 ₄ portion projecting from _and then sequentially provided by cutting a diameter dry seal portion 6 _5, pulley coupling section 6 _6, the timing gear case Z the portion projecting _first timing gear connecting portion 6 ₇ graded followed bearing insert 6 _2, to form the threaded portion 6 _8.

Sealing holes L ₁ and R are formed in the housings L and R in correspondence with the bearing insertion portions 6 ₂ and 6 ₂ of the rotor shaft 6.
₁ and the bearing holes L ₂ and R ₂ are formed in two stages, and the seal holes L ₁ and R ₁ are provided with communication holes 10 and 10 that communicate with the inner cavities of the first-stage casing 7 and the rear-stage casing 8, respectively. All of the seal holes L ₁ and R ₁ and the bearing hole L ₂ ,
A dry seal adapter with an L-shaped cross section on a very small part of R ₂
1 is fitted with each communication hole 10 closed, and a dry seal 1 corresponding to the vacuum side including the first stage and the second stage casings 7 and 8 on the inner surface.
2 and 12 are fitted, and dry seals 13 and 13 having H-shaped cross sections and bearings 15 and 15 are fitted to the bearing holes L ₂ and R ₂ . Further, the sleeve so as to correspond to a portion of the inner end of the dry seal 12 and 13 to the bearing insert ₆ 2, _{6 2} 14,1
4, and each sleeve 14 and each dry seal 1
The vacuum side dry type slinger assembly A, A is constituted by 2 and 13. Between the sleeves 14 and 14 and the inner diameters of the bearings 15 and 15, the bearing inserts 6 ₂ and 6 ₂
The spacers 16 and 16 are fitted in. (Detailed configuration corresponding to bearing insert 6 ₂ of the housing R side omit part of the code because it is 3 and symmetrically.)

[0013] Oil slinger attachment portion 6 ₃ projecting in an oil bath and Y, attaching the oil slinger 21 sandwiched by a nut. (Fig. 4). A shaft hole of the oil bath cover Y ₁ of the screw-shaped slinger 6 ₄ passes is fitted a seal ring adapter 22 from the outside, the flow TIG sheet 23 fixed to the dry seal portion 6 ₅ in the adapter 22, of the sheet 23 The atmosphere side mechanical seal assembly B is constituted by the seal ring 24 which is in contact with the vacuum side (FIG. 4). The seal ring 24, and interior spring 25 which presses the ring 24 in a floating sheet 23 in contact with the inner surface of the adapter 22 is provided with a case 26 that substantially in contact against the threaded slinger 6 _4. Flow TIG The outer sheet 23 is provided with a sleeve 27 fitted to the dry seal portion 6 ₅ fixed by a nut 28, the outer opening of the adapter 22, attached to air-side adapter 29 to the lid-shaped, the adapter 28 A dry seal 30 contacting the inner periphery of the sleeve 27 is attached to the center hole of the above, and the atmosphere dry side assembly C is constituted by the sleeve 27 and the dry seal 30. Also floating sheet 23
A dry room 31 is provided around the atmosphere side.

[0014] securing the pulley 32 to the pulley coupling section _{6 6.}

Timing gear connecting portion 6 on the housing R side
₇ fitted with a known timing gear 41 which rotates with the part to oil in the oil room Z, subjected to fixing in a known manner by a nut 42 screwed on the threaded portion 6 _8.

[0016]

The shaft seal structure of the multi-stage roots blower for vacuum of the present invention prevents the inflow of air, the outflow of oil, the inflow of oil and air into the casing, and the long-term use, and the cost reduction. May be significantly reduced. These were clarified in the section of action. When sufficiently cooled by the action of the oil slinger 21 can omit the shaft threaded oil slinger 6 _5.

[Brief description of drawings]

 The accompanying drawings show an embodiment of the present invention,

[Figure 1] Front view of the vertical section of the center

FIG. 2 is a perspective view of a roots type rotor on a motor driving side.

FIG. 3 is an enlarged vertical sectional view of a part of FIG.

FIG. 4 is an enlarged vertical sectional view of another part of FIG.

[Explanation of symbols] X multi-stage vacuum roots type blower, A vacuum side dry type slinger assembly, B atmosphere side mechanical seal assembly, C atmosphere side dry seal assembly, L, R housing, Y oil bath, Y ₁
Cover, Z oil bathroom, Z ₁ timing gear case, L ₁ , R ₁ seal hole, L ₂ , R ₂ bearing hole, 1 grain, 2 eyebrow type rotor, 3 first stage roots type rotor, 4 second stage roots type rotor, 6 Rotor shaft, 6 ₁ connecting part, 6 ₂ bearing inserting part, 6
₃ oil slinger attachment part, 6 ₄ threaded slinger, 6 ₅ dry seal part, 6 ₆ pulley connection part,
6 ₇ timing gear connecting part, 6 ₈ screw part, 7 first stage casing, 8 rear stage casing, 9 bulkhead, 1
0 communication hole, 11 draft seal adapter, 12
Dry seal, 13 dry seal, 14 sleeve, 15 bearing, 16 spacer, 21 oil slinger, 22 seal ring adapter, 23
Flow sheet, 24 seal ring, 25 spring, 26 case, 27 sleeve, 28 nut, 29 adapter, 30 dry seal, 31
Dry room, 32 pulley, 41 timing gear, 42 nut

Claims (1)

[Claims] 1. A multi-stage or single-stage vacuum roots blower for vacuum, wherein a mechanical seal assembly B on the atmosphere side is provided, and the bearing 15 is forced to the atmosphere side of a bearing 15 of a housing L having an oil bath Y on the outside. the slinger 21 of cooling provided on the vacuum side of the bearing 15, so as to correspond to a portion of the inner surface of the dry seal 12 and the dry seal 13, bearing insert 6 ₂ of the rotor shaft 6
The sleeve 14 by Katahama, the vacuum side dry formula slinger assembly A constituted by the said sleeve 14 and the dry seal 12 is provided, the floating sheet 23 fixed to the dry seal portion 6 ₅ of the rotor shaft 6 An atmosphere-side dry seal assembly C including a sleeve 27 fitted to the atmosphere side and a dry seal 29 contacting the inner surface of the sleeve is provided, and the synergistic effect of each of the above-mentioned parts causes an inflow of air, an outflow of oil, an oil to a vacuum chamber. Roots blower seal structure that prevents the inflow of air.