CN105889068A - Screw vacuum pump with piston ring sealing and mechanical sealing structures - Google Patents

Screw vacuum pump with piston ring sealing and mechanical sealing structures Download PDF

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Publication number
CN105889068A
CN105889068A CN201610404778.8A CN201610404778A CN105889068A CN 105889068 A CN105889068 A CN 105889068A CN 201610404778 A CN201610404778 A CN 201610404778A CN 105889068 A CN105889068 A CN 105889068A
Authority
CN
China
Prior art keywords
piston ring
rotor
seat
vacuum pump
suction end
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201610404778.8A
Other languages
Chinese (zh)
Inventor
茆林凤
陆洪华
谷军
张卫卫
徐明星
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
WUXI CITY SIFANG VACUUM EQUIPMENT CO Ltd
Original Assignee
WUXI CITY SIFANG VACUUM EQUIPMENT CO Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by WUXI CITY SIFANG VACUUM EQUIPMENT CO Ltd filed Critical WUXI CITY SIFANG VACUUM EQUIPMENT CO Ltd
Priority to CN201610404778.8A priority Critical patent/CN105889068A/en
Publication of CN105889068A publication Critical patent/CN105889068A/en
Pending legal-status Critical Current

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04CROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/08Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C18/12Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
    • F04C18/14Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons
    • F04C18/16Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons with helical teeth, e.g. chevron-shaped, screw type
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04CROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C25/00Adaptations of pumps for special use of pumps for elastic fluids
    • F04C25/02Adaptations of pumps for special use of pumps for elastic fluids for producing high vacuum
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04CROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C27/00Sealing arrangements in rotary-piston pumps specially adapted for elastic fluids

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)

Abstract

The invention relates to a screw vacuum pump, in particular to a screw vacuum pump with piston ring sealing structures, and belongs to the technical field of screw pump sealing structures. The screw vacuum pump comprises a pump body, an air exhaust end of the pump body is connected with a front end cover, an air exhaust end of a drive rotor and an air exhaust end of a driven rotor are connected with the front end cover through angular contact ball bearings respectively, and air exhaust end sealing structures are arranged between the front end cover and the drive rotor and between the front end cover and the driven rotor respectively; an air inlet end of the pump body is connected with a back end cover, an air suction end of the drive rotor and an air suction end of the driven rotor are connected with the back end cover through deep groove ball bearings respectively, and air suction end sealing structures are arranged between the back end cover and the drive rotor and between the back end cover and the driven rotor respectively. According to the screw vacuum pump, the mechanical sealing structures re adopted at the air exhaust ends, and therefore cleanliness of the air exhaust end bearings, gears and lubricating oil; at the air suction ends, due to the fact that the inlet pressure is smaller than the atmosphere pressure, piston ring sealing can be adopted as back end cover sealing, and then it is guaranteed that the screw pump can work for a long time.

Description

A kind of have a piston ring packing and machine is sealed the screw vacuum pump of seal structure
Technical field
The present invention relates to a kind of screw vacuum pump, a kind of have a seal structure for piston ring and screw vacuum pump that mechanical seal structure combines, belongs to screw pump and seals technical field of structures.
Background technology
Screw pump vacuum is the mechanical pump of a kind of novel intake-gas, and feature is that structure is relatively easy, advanced technology, insensitive to intake-gas.Pumping speed scope is wide, pollution-free.Can combine with lobe pump etc., the advantage meeting big rate of air sucked in required, condition of high vacuum degree, low energy consumption, it is also possible to be used alone, have wide range of applications, be the substitute products of the mechanical pump such as sliding vane rotary pump, water ring pump.
In prior art, the axle head of screw vacuum pump plays sealing effectiveness by arranging outside framework oil seal, but long-play easily makes axle head fever expansion, outside framework oil seal abrasion accelerate, and has influence on sealing effectiveness, affects the normal use of screw vacuum pump time serious.
Summary of the invention
It is an object of the invention to overcome above-mentioned weak point, thus provide a kind of and there is piston ring packing and machine is sealed the screw vacuum pump of seal structure, good radiating effect can be had while ensureing sealing effectiveness, the situation avoiding screw shaft to be rapidly heated occurs, it is ensured that screw vacuum pump can work long hours.
The technical scheme provided according to the present invention, a kind of have a seal structure for piston ring and screw vacuum pump that mechanical seal structure combines includes the pump housing, the pump housing is provided with air entry, power rotor and passive rotor it is provided with side by side in the pump housing, the exhaust end of power rotor connects motor by shaft coupling, power rotor drives passive rotor synchronous backward together to rotate by meshed gears drive mechanism, it is characterized in that: the exhaust end of the pump housing connects drive end bearing bracket, the exhaust end of power rotor and passive rotor connects drive end bearing bracket by angular contact ball bearing, drive end bearing bracket and power rotor, it is equipped with exhaust end between passive rotor and seals structure;
Described exhaust end seals structure and includes prelocalization dish, machine envelope axle sleeve, mechanical seal, stationary seat, piston ring seat and piston ring, it is arranged side by side before and after machine envelope axle sleeve and piston ring seat, piston ring seat outer ring is provided with multiple piston ring, piston ring seat outer ring is provided with prelocalization dish, multiple piston rings are fixed in piston ring seat by prelocalization dish, machine envelope axle sleeve outer ring is provided with stationary seat, and machine envelope stationary ring is fixed in stationary seat;
The inlet end of the pump housing connects rear end cap, and the suction end of power rotor and passive rotor connects rear end cap by deep groove ball bearing, is equipped with suction end and seals structure between rear end cap and power rotor, passive rotor;
Described suction end seals location dish after structure includes, suction end piston ring seat, suction end first piston ring, suction end the second piston ring and bearing block, suction end piston ring seat outer ring is provided with bearing block and rear location dish side by side, it is provided with suction end first piston ring between suction end piston ring seat and bearing block, between suction end piston ring seat and rear location dish, is provided with suction end the second piston ring.
Further, gear drive includes actively travelling gear and slave drive gear, is provided with actively travelling gear on power rotor exhaust end, is provided with driven eating on the exhaust end of passive rotor, and power rotor and passive rotor are by gear engagement rotation.
Further, drive end bearing bracket connects front shroud, stretches out the movable sealing structure in the external world in front shroud containing power rotor.
Further, rear end cap rear end connects back shroud, and back shroud plays the static seal effect of ambient atmos and pump housing isolation.
Further, mechanical seal includes rotating ring and stationary ring, and stationary ring is arranged in stationary seat, and rotating ring is arranged in machine envelope axle sleeve, and rotating ring compresses stationary ring.
Compared with the prior art the present invention has the advantage that
Present configuration is simple, compact, reasonable, and cost is relatively low, stable and reliable in work;Good radiating effect can be had, it is to avoid the situation that screw vacuum pump shaft is rapidly heated occurs, it is ensured that screw vacuum pump can work long hours while ensureing sealing effectiveness;The mechanism of mechanical seal is used, it is ensured that the cleaning of discharge end bearings, gear and lubricating oil is clean at exhaust end;At suction end owing to population pressure is less than atmospheric pressure, therefore rear end cap seals and can use piston ring packing, thus ensures that screw pump can work long hours.
Accompanying drawing explanation
Fig. 1 is front view of the present invention.
Fig. 2 is enlarged drawing at A in Fig. 1.
Fig. 3 is enlarged drawing at B in Fig. 1.
Description of reference numerals: the 1-pump housing, 2-rear end cap, 3-drive end bearing bracket, 4-front shroud, 5-motor, 6-shaft coupling, 7-actively travelling gear, 8-slave drive gear, 9-power rotor, 10-passive rotor, 11-angular contact ball bearing, 12-prelocalization dish, 13-machine envelope axle sleeve, 14-mechanical seal, 14.1-rotating ring, 14.2-stationary ring, 15-stationary seat, 16-piston ring seat, 17-piston ring, location dish after 18-, 19-back shroud, 20-deep groove ball bearing, location dish after 21-, 22-suction end piston ring seat, 23-suction end first piston ring, 24-suction end the second piston ring, 25-bearing block.
Detailed description of the invention
The embodiment combined in accompanying drawing is further described by the present invention below:
As it is shown in figure 1, the invention mainly comprises the pump housing 1, being provided with power rotor 9 and passive rotor 10 in the pump housing 1 side by side, the exhaust end of power rotor 9 connects motor 5 by shaft coupling 6, drives power rotor 9 to rotate by motor 5.
Power rotor 9 drives passive rotor 10 synchronous backward together to rotate by meshed gears drive mechanism, described gear drive includes actively travelling gear 7 and slave drive gear 8, power rotor 9 exhaust end is provided with actively travelling gear 7, being provided with passive rotor 10 on the exhaust end of passive rotor 10, power rotor 9 is connected with passive rotor 10 engagement.
The pump housing 1 is provided with air entry, and gas is sucked by the air entry on the pump housing, and carry through power rotor 9 and passive rotor 10, to be compressed to exhaust end excavationg pump external.
The exhaust end of the pump housing 1 connects drive end bearing bracket 3, and drive end bearing bracket 3 front end connects front shroud 4, and the exhaust end of power rotor 9 and passive rotor 10 is sealed in front shroud 4 by front shroud 4.The exhaust end of power rotor 9 and passive rotor 10 connects drive end bearing bracket 3 by angular contact ball bearing 11.Being in the gas exhaust end of screw vacuum pump at drive end bearing bracket, its pressure at expulsion should be greater than atmospheric pressure, in order to stop gas, material to enter in drive end bearing bracket, therefore uses and seals reliable mechanical seal structure.It is equipped with exhaust end between described drive end bearing bracket 3 and power rotor 9, passive rotor 10 and seals structure.
As shown in Figure 3, described exhaust end seals structure and includes prelocalization dish 12, machine envelope axle sleeve 13, mechanical seal 14, stationary seat 15, piston ring seat 16 and piston ring 17, it is arranged side by side before and after machine envelope axle sleeve 13 and piston ring seat 16, piston ring seat 16 outer ring is provided with multiple piston ring 17, piston ring seat 16 outer ring is provided with prelocalization dish 12, and multiple piston rings 17 are fixed in piston ring seat 16 by prelocalization dish 12.Machine envelope axle sleeve 13 outer ring is provided with stationary seat 15, and mechanical seal 14 is pressed on machine envelope axle sleeve 13 by stationary seat 15.
Mechanical seal 14 includes rotating ring 14.1 and stationary ring 14.2, and stationary ring 14.2 is arranged in stationary seat 15, and rotating ring 14.1 is arranged in machine envelope axle sleeve 13, and rotating ring 14.1 compresses stationary ring 14.2.
The effect of mechanical seal 14 is to stop the gas of the pump housing, material etc. to enter at the parts such as bearing, gear, and protection bearing, gear and lubricating oil are from erosion.
The inlet end of the pump housing 1 connects rear end cap 2, rear end cap 2 rear end connects back shroud 19, the suction end of power rotor 9 and passive rotor 10 is sealed in back shroud 19 by back shroud 19, and the suction end of power rotor 9 and passive rotor 10 connects rear end cap 2 by deep groove ball bearing 20.In view of rear end cover structure inside is atmospheric pressure, and pump housing air entry operating pressure at rear end cap, air entry answers subatmospheric power, therefore according to gas flow direction, the gas of pump housing suction inlet, material will not enter in rear end cap, so rear end cap uses conventional piston ring packing to meet.It is equipped with suction end between described rear end cap 2 and power rotor 9, passive rotor 10 and seals structure.
As shown in Figure 2, described suction end seals location dish 21 after structure includes, suction end piston ring seat 22, suction end first piston ring 23, suction end the second piston ring 24 and bearing block 25, suction end piston ring seat 22 outer ring is provided with bearing block 25 and rear location dish 21 side by side, it is provided with suction end first piston ring 23 between suction end piston ring seat 22 and bearing block 25, between suction end piston ring seat 22 and rear location dish 21, is provided with suction end the second piston ring 24.
Present configuration is simple, compact, reasonable, and cost is relatively low, stable and reliable in work;Good radiating effect can be had, it is to avoid the situation that screw vacuum pump shaft is rapidly heated occurs, it is ensured that screw vacuum pump can work long hours while ensureing sealing effectiveness;The mechanism of mechanical seal is used, it is ensured that the cleaning of discharge end bearings, gear and lubricating oil is clean at exhaust end;At suction end owing to population pressure is less than atmospheric pressure, therefore rear end cap seals and can use piston ring packing, thus ensures that screw pump can work long hours.

Claims (5)

1. one kind has a piston ring packing and machine is sealed the screw vacuum pump of seal structure, including the pump housing (1), the pump housing (1) is provided with air entry, power rotor (9) and passive rotor (10) it is provided with side by side in the pump housing (1), the exhaust end of power rotor (9) connects motor (5) by shaft coupling (6), power rotor (9) drives passive rotor (10) synchronous backward together to rotate by meshed gears drive mechanism, it is characterized in that: the exhaust end of the pump housing (1) connects drive end bearing bracket (3), the exhaust end of power rotor (9) and passive rotor (10) connects drive end bearing bracket (3) by angular contact ball bearing (11), drive end bearing bracket (3) and power rotor (9), it is equipped with exhaust end between passive rotor (10) and seals structure;
Described exhaust end seals structure and includes prelocalization dish (12), machine envelope axle sleeve (13), mechanical seal (14), stationary seat (15), piston ring seat (16) and piston ring (17), it is arranged side by side before and after machine envelope axle sleeve (13) and piston ring seat (16), piston ring seat (16) outer ring is provided with multiple piston ring (17), piston ring seat (16) outer ring is provided with prelocalization dish (12), multiple piston rings (17) are pressed in piston ring seat (16) by prelocalization dish (12), machine envelope axle sleeve (13) outer ring is provided with stationary seat (15), mechanical seal (14) is pressed on machine envelope axle sleeve (13) by stationary seat (15);
The inlet end of the pump housing (1) connects rear end cap (2), the suction end of power rotor (9) and passive rotor (10) connects rear end cap (2) by deep groove ball bearing (20), is equipped with suction end and seals structure between rear end cap (2) and power rotor (9), passive rotor (10);
Described suction end seals location dish (21) after structure includes, suction end piston ring seat (22), suction end first piston ring (23), suction end the second piston ring (24) and bearing block (25), suction end piston ring seat (22) outer ring is provided with bearing block (25) and rear location dish (21) side by side, it is provided with suction end first piston ring (23) between suction end piston ring seat (22) and bearing block (25), between suction end piston ring seat (22) and rear location dish (21), is provided with suction end the second piston ring (24).
A kind of have a piston ring packing and machine is sealed the screw vacuum pump of seal structure, it is characterized in that: described gear drive includes actively travelling gear (7) and slave drive gear (8), power rotor (9) exhaust end is provided with actively travelling gear (7), being provided with passive rotor (10) on the exhaust end of passive rotor (10), power rotor (9) is connected with passive rotor (10) engagement.
A kind of have a piston ring packing and machine is sealed the screw vacuum pump of seal structure, it is characterized in that: described drive end bearing bracket (3) front end connects front shroud (4), the exhaust end of power rotor (9) and passive rotor (10) is sealed in front shroud (4) by front shroud (4).
A kind of have a piston ring packing and machine is sealed the screw vacuum pump of seal structure, it is characterized in that: described rear end cap (2) rear end connects back shroud (19), the suction end of power rotor (9) and passive rotor (10) is sealed in back shroud (19) by back shroud (19).
A kind of have a piston ring packing and machine is sealed the screw vacuum pump of seal structure, it is characterized in that: described mechanical seal (14) includes rotating ring (14.1) and stationary ring (14.2), stationary ring (14.2) is arranged in stationary seat (15), rotating ring (14.1) is arranged in machine envelope axle sleeve (13), and rotating ring (14.1) compresses stationary ring (14.2).
CN201610404778.8A 2016-06-12 2016-06-12 Screw vacuum pump with piston ring sealing and mechanical sealing structures Pending CN105889068A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201610404778.8A CN105889068A (en) 2016-06-12 2016-06-12 Screw vacuum pump with piston ring sealing and mechanical sealing structures

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201610404778.8A CN105889068A (en) 2016-06-12 2016-06-12 Screw vacuum pump with piston ring sealing and mechanical sealing structures

Publications (1)

Publication Number Publication Date
CN105889068A true CN105889068A (en) 2016-08-24

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CN201610404778.8A Pending CN105889068A (en) 2016-06-12 2016-06-12 Screw vacuum pump with piston ring sealing and mechanical sealing structures

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111749891A (en) * 2020-05-27 2020-10-09 浙江珂勒曦动力设备股份有限公司 Bearing lubricating structure of screw blower or vacuum pump
CN116857191A (en) * 2023-05-10 2023-10-10 上海汉钟精机股份有限公司 Vapor screw compressor with non-contact sealing structure

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201344126Y (en) * 2008-11-21 2009-11-11 山东伯仲真空设备有限公司 Oil-less dry type screw vacuum pump
JP2010053799A (en) * 2008-08-29 2010-03-11 Hitachi Plant Technologies Ltd Screw compressor
CN102588287A (en) * 2012-02-08 2012-07-18 奉化市釜用密封件有限公司 Mechanical sealing parts of Roots blower and lubricating method thereof
CN203500004U (en) * 2013-09-29 2014-03-26 山东伯仲真空设备股份有限公司 Mechanical-seal Roots vacuum pump
CN204663879U (en) * 2015-04-10 2015-09-23 镇江纽普兰气力输送有限公司 Energy-saving and high-pressure Roots blower
CN204677432U (en) * 2015-05-04 2015-09-30 江阴天田真空设备制造有限公司 Full mechanical seal Roots pump
CN105649987A (en) * 2014-11-11 2016-06-08 中国科学院沈阳科学仪器股份有限公司 Compound seal used for vacuum pump
CN205714762U (en) * 2016-06-12 2016-11-23 无锡市四方真空设备有限公司 A kind of have a piston ring packing and machine is sealed the screw vacuum pump of seal structure

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010053799A (en) * 2008-08-29 2010-03-11 Hitachi Plant Technologies Ltd Screw compressor
CN201344126Y (en) * 2008-11-21 2009-11-11 山东伯仲真空设备有限公司 Oil-less dry type screw vacuum pump
CN102588287A (en) * 2012-02-08 2012-07-18 奉化市釜用密封件有限公司 Mechanical sealing parts of Roots blower and lubricating method thereof
CN203500004U (en) * 2013-09-29 2014-03-26 山东伯仲真空设备股份有限公司 Mechanical-seal Roots vacuum pump
CN105649987A (en) * 2014-11-11 2016-06-08 中国科学院沈阳科学仪器股份有限公司 Compound seal used for vacuum pump
CN204663879U (en) * 2015-04-10 2015-09-23 镇江纽普兰气力输送有限公司 Energy-saving and high-pressure Roots blower
CN204677432U (en) * 2015-05-04 2015-09-30 江阴天田真空设备制造有限公司 Full mechanical seal Roots pump
CN205714762U (en) * 2016-06-12 2016-11-23 无锡市四方真空设备有限公司 A kind of have a piston ring packing and machine is sealed the screw vacuum pump of seal structure

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111749891A (en) * 2020-05-27 2020-10-09 浙江珂勒曦动力设备股份有限公司 Bearing lubricating structure of screw blower or vacuum pump
CN111749891B (en) * 2020-05-27 2022-06-03 浙江珂勒曦动力设备股份有限公司 Bearing lubricating structure of screw blower or vacuum pump
CN116857191A (en) * 2023-05-10 2023-10-10 上海汉钟精机股份有限公司 Vapor screw compressor with non-contact sealing structure
CN116857191B (en) * 2023-05-10 2024-03-19 上海汉钟精机股份有限公司 Vapor screw compressor with non-contact sealing structure

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Application publication date: 20160824

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