US20030035738A1 - Roots vacuum pump - Google Patents
Roots vacuum pump Download PDFInfo
- Publication number
- US20030035738A1 US20030035738A1 US09/962,446 US96244601A US2003035738A1 US 20030035738 A1 US20030035738 A1 US 20030035738A1 US 96244601 A US96244601 A US 96244601A US 2003035738 A1 US2003035738 A1 US 2003035738A1
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- Prior art keywords
- pump
- roots
- exhaust port
- motor
- bypass path
- 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.)
- Abandoned
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- 238000007789 sealing Methods 0.000 claims description 4
- 230000006835 compression Effects 0.000 abstract description 6
- 238000007906 compression Methods 0.000 abstract description 6
- 238000013461 design Methods 0.000 abstract description 3
- 230000003247 decreasing effect Effects 0.000 description 5
- 238000012545 processing Methods 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
Images
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
- F04C18/08—Rotary-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
- F04C18/12—Rotary-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
- F04C18/14—Rotary-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
- F04C18/18—Rotary-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 similar tooth forms
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
- F04C28/24—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids characterised by using valves controlling pressure or flow rate, e.g. discharge valves or unloading valves
- F04C28/26—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids characterised by using valves controlling pressure or flow rate, e.g. discharge valves or unloading valves using bypass channels
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
- F04C18/08—Rotary-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
- F04C18/12—Rotary-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
- F04C18/126—Rotary-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 radially from the rotor body extending elements, not necessarily co-operating with corresponding recesses in the other rotor, e.g. lobes, Roots type
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
- F04C23/005—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids of dissimilar working principle
Definitions
- the present invention relates to a roots vacuum pump, and in particular to an improved roots vacuum pump which is capable of preventing a pump and motor from being damaged by an exhaust pressure by implementing a constant exhaust pressure of a roots pump for thereby significantly decreasing a working time by concurrently operating a roots pump and a latter part pump.
- a roots pump apparatus is called as a mechanical booster and is used for processing a lot of gas at a short time, and an ultimate pressure is determined based on a latter part pump. The roots pump is not used lonely.
- the roots vacuum pump apparatus represents a connection member between the roots pump and the latter part pump), as shown in FIG. 1, the roots pump and the latter part pump are connected, and the exhaust rate ratio between the latter part pump and the roots pump is 1:4-6.
- the gas sucked and discharged by the roots pump is not fully exhausted by the latter part pump due to a processing capacity difference, so that a part of compression gas remains in a portion between an exhaust port of the rots pump and a suction port of the latter part pump.
- the compression gas which is not exhausted by the latter part pump and remains in a portion near of the exhaust port of the roots pump is guided to the suction port of the roots pump through a bypass return line 101 by opening a check valve 100 in order to enhance an efficiency by concurrently operating the roots pump and the latter part pump for thereby preventing an over load.
- a roots vacuum pump which includes bypass paths formed in at least one inner surface among the inner surfaces of the front cover and the rear cover for communicating the suction pot and exhaust port of the cylinder, and an one-way valve installed in an inlet of the bypass path contacting with the exhaust port for opening the bypass path when a pressure of the exhaust port exceeds a certain level in the roots vacuum pump apparatus in which a suction port and an exhaust port are formed at both sides of a roots pump cylinder having a pair of rotors which are supported by a rotary shaft and are rotated in an engaged state, a front cover and motor fixing plate are sequentially engaged in one side of the cylinder, and a rear cover and a gear box are sequentially engaged in the other side of the same, and an exhaust port is connected with the latter part pump.
- the one-way valve includes a valve guide installed in a wall surface of the cover opposite to the inlet of the bypass path, a valve member movable based on a guide of a valve guide for opening and closing the inlet of the bypass path an opposite direction with respect to the valve guide, an elastic member disposed between the valve member and the valve guide for generating a certain elastic force in order for the valve member to closely contact with the inlet of the bypass path, and an O-ring formed in a contact surface of the valve member.
- a motor housing is engaged to one side of the motor fixing plate, and a can housing is engaged in such a manner that the interior of the motor housing is sealed, and a stator is installed in the interior of the can housing, and a motor rotor is fixed in an outer surface of the rotary shaft in such a manner that the motor rotor is protruded to the outside of the motor fixing plate for thereby implementing a good sealing state and an easier attaching and detaching operation of the motor.
- FIG. 1 is a view illustrating an example of use of a conventional roots vacuum pump
- FIG. 2 is a cross-sectional view illustrating a roots vacuum pump according to the present invention
- FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2;
- FIG. 4 is a cross-sectional view taken along line B-B of FIG. 2;
- FIG. 5 is a cross-sectional view taken along line C-C of FIG. 2;
- FIGS. 6 and 7 are views illustrating an operation state of a valve adapted to a roots vacuum pump according to the present invention.
- reference numeral 1 represents a cylinder of a roots pump, and a suction port 11 and an exhaust port 12 are formed in the upper and lower sides of the cylinder 1 , and a pair of rotors 13 are installed in the interior of the cylinder 1 and are supported by a rotary shaft 56 .
- a motor rotor 55 is fixed at an outer surface of the rotary shaft 56 protruded to an outer portion of a motor fixing plate 5 , and a sealed can housing 53 is formed in the inner side of a motor housing 52 .
- a stator 54 is fixed in the interior of the can housing 53 , so that the canned motor 51 is easily engaged by engaging the motor housing 52 to the motor fixing plate 5 .
- the motor housing 52 Since the can housing 53 and the motor housing 52 are module-engaged, the motor housing 52 is engaged to the motor fixing plate 5 using a bolt for thereby completing an engagement of the motor. It is possible to easily disassembly the motor by separating the motor housing 52 from the motor fixing plate 5 .
- a cooling fan 58 is formed in the latter part of the motor housing 52 for preventing an over-heating of the motor, so that even when the canned motor 51 is operated for a long time, it is not over-headed and damaged.
- a cylindrical can 75 sealingly separates the stator 54 and the motor rotor 55 for thereby implementing a sealed state in the pump.
- a rear cover 3 and a gear box 4 are sequentially installed in the other side of the cylinder 1 .
- a gear apparatus is installed in the interior of the gear box 4 for thereby uniformly supplying a driving force to the rotors 13 .
- a bypass path is formed in either a front cover 2 or the rear cover 3 .
- first and second bypass paths 21 and 31 are formed in the front cover 2 and the rear cover 3 , respectively.
- the first bypass path 21 is formed in the interior of the front cover 2 for connecting the suction port 11 and the exhaust port 12 , and an inlet 22 of the first bypass path 21 communicates with an outlet 12 of the cylinder 1 , and the outlet 23 of the first bypass path 21 communicates with the suction port 11 of the cylinder 1 .
- the second bypass path 31 is formed in the interior of the rear cover 3 for connecting the suction port 11 and the exhaust port 12 , and an inlet 32 of the second bypass path 21 communicates with the exhaust port 12 , and the outlet 33 of the same communicates with the suction port 11 of the cylinder 1 .
- One-way valves 60 and 62 are formed in the inlets 22 and 32 of the bypass paths 21 and 31 , and a valve guide 62 is installed in a wall surface of the front cover 2 and the rear cover 3 opposite to the inlets 22 and 32 of the first and second bypass paths 21 and 31 , and an opening and closing valve member 63 which is moved along the valve guide 62 is formed in a portion opposite to the valve guide 62 .
- An elastic member 64 is installed between the valve member 63 and the valve guide 62 for applying a certain elastic force thereto, so that the valve member 63 blocks the inlets 22 and 32 of the bypass paths 21 and 31 by an elastic force of the elastic member 64 .
- An O-ring 65 is installed in a sealed surface of the valve member 63 , namely, in the wall surface of the inlets 22 and 32 . Therefore, when the valve member 63 blocks the inlets 22 and 32 , a sealing ratio is significantly increased by the O-ring 65 .
- a filter 71 is formed in the upper wall surface of the gear box 4 for filtering a foreign substance from the oil and gas.
- An outlet of the filter 71 is connected with the second bypass path 21 , and a communication hole 74 is formed in the contact surface between the gear box 4 and the rear cover 3 .
- a connection path 74 which connects the interior of the gear box 4 and the interior of the motor fixing plate 5 is formed in an inner wall surface of the cylinder 1 as shown in FIG. 3.
- a nozzle hole 72 having a certain size which connects the interior of the gear box 4 and the filter 71 is formed in the wall surface of the gear box 4 .
- reference numeral 57 represents a bearing which rotatably supports the rotary shaft 56 .
- the gas pressure is increased.
- the valve member 63 compresses the elastic member 64 and moves for thereby opening the inlets 22 and 32 of the first and second bypass paths 21 and 31 .
- the inlets 22 and 32 are opened, the gas in the exhaust port 12 is bypassed to the suction port 11 of the cylinder 1 through the bypass paths 21 and 31 and is recirculated for thereby decreasing the gas pressure in the side of the exhaust port 12 .
- valve member 63 When the gas pressure in the side of the exhaust port 12 is decreased, the valve member 63 is forwardly moved by an elastic force of the elastic member 64 for thereby blocking the inlets 21 and 31 of the first and second bypass paths 21 and 31 as shown in FIG. 6.
- valve member 63 blocks the inlets 21 and 31 , since the O-ring 65 closely contacts with the inlets 21 and 31 for thereby implementing a good sealing state.
- bypass paths are formed in the interiors of the front cover and rear cover, respectively, an outer appearance of the roots vacuum pump is good, and the size of the pump is decreased.
- the bypass paths are formed in the interiors of the front cover and the rear cover for connecting the suction port side and the exhaust port side of the roots pump cylinder.
- An one-way valve which is automatically opened and closed when an exhaust pressure in the side of the exhaust of the cylinder exceeds a certain reference value is formed in the inlet of the bypass path, so that it is possible to prevent a certain dampage of the pump apparatus and the motor due to the over load by bypassing the remaining compression gas which is not processed by the latter part pump to the side of the roots pump suction port.
- the roots pump and the latter pat pump which have a large capacity difference are concurrently processed, it is possible to significantly decrease the working time, and since the bypass paths are formed in the pump housing, not in the outside of the system, an outer appearance looks good, and the layout of the design is not limited.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Applications Or Details Of Rotary Compressors (AREA)
Abstract
The present invention relates to a roots vacuum pump which is capable of implementing a good outer appearance and an improved layout design of a pump by forming a certain path through which a remaining compression gas is returned to a suction port side of a roots pump in a housing of a roots pump in the case that a gas compressed by a roots pump is not fully exhausted by a latter part pump and remains in an exhaust pot side of the roots pump and is capable of concurrently operating a roots pump and a latter part pump. The roots vacuum pump apparatus in which a root pump and a latter part pump are connected, includes bypass paths formed in at least one inner surface among the inner surfaces of the front cover and the rear cover for communicating the suction pot and exhaust port of the cylinder, and an one-way valve installed in an inlet of the bypass path contacting with the exhaust port for opening the bypass path when a pressure of the exhaust port exceeds a certain level.
Description
- 1. Field of the Invention
- The present invention relates to a roots vacuum pump, and in particular to an improved roots vacuum pump which is capable of preventing a pump and motor from being damaged by an exhaust pressure by implementing a constant exhaust pressure of a roots pump for thereby significantly decreasing a working time by concurrently operating a roots pump and a latter part pump.
- 2. Description of the Background Art
- A roots pump apparatus is called as a mechanical booster and is used for processing a lot of gas at a short time, and an ultimate pressure is determined based on a latter part pump. The roots pump is not used lonely.
- Namely, when using the roots vacuum pump apparatus(hereinafter, the roots vacuum pump apparatus represents a connection member between the roots pump and the latter part pump), as shown in FIG. 1, the roots pump and the latter part pump are connected, and the exhaust rate ratio between the latter part pump and the roots pump is 1:4-6. When the combined pumps are concurrently used, the gas sucked and discharged by the roots pump is not fully exhausted by the latter part pump due to a processing capacity difference, so that a part of compression gas remains in a portion between an exhaust port of the rots pump and a suction port of the latter part pump.
- When the gas discharged from the roots pump is not fully exhausted and remains in the portion between the latter part pump and the roots pump, as the roots pump is operated, the pressure in the outlet side of the roots pump is gradually increased. Finally, the roots pump is over-loaded by a high pressure, so that the parts of the rotor of the roots pump and the motor are damaged.
- In order to overcome the above problems, a certain work is processed using the latter pat pump with respect to a pressure under a vacuum degree of about 10 Torr of the vacuum facility. The above-described sequential driving method of the pump requires a long working time since the roots pump and the latter pumps are concurrently operated, and the structure of the vacuum system is complicated.
- In another example, the compression gas which is not exhausted by the latter part pump and remains in a portion near of the exhaust port of the roots pump is guided to the suction port of the roots pump through a
bypass return line 101 by opening acheck valve 100 in order to enhance an efficiency by concurrently operating the roots pump and the latter part pump for thereby preventing an over load. - However, in the above return method of the remaining compression gas requires an external
bypass return line 101 of the roots pump, an outer apparance is bad and causes an interference with another structure of the pump, so that when designing the system, a layout of the system is limited. - Accordingly, it is an object of the present invention to provide a roots vacuum pump which overcomes the problems encountered in a conventional cylinder structure.
- It is another object of the present invention to provide a roots vacuum pump which is capable of implementing a good outer appearance and an improved layout design of a pump by forming a certain path through which a remaining compression gas is returned to a suction port side of a roots pump in a housing of a roots pump in the case that a gas compressed by a roots pump is not fully exhausted by a latter part pump and remains in an exhaust pot side of the roots pump and is capable of concurrently operating a roots pump and a latter part pump.
- To achieve the above object, there is provided a roots vacuum pump which includes bypass paths formed in at least one inner surface among the inner surfaces of the front cover and the rear cover for communicating the suction pot and exhaust port of the cylinder, and an one-way valve installed in an inlet of the bypass path contacting with the exhaust port for opening the bypass path when a pressure of the exhaust port exceeds a certain level in the roots vacuum pump apparatus in which a suction port and an exhaust port are formed at both sides of a roots pump cylinder having a pair of rotors which are supported by a rotary shaft and are rotated in an engaged state, a front cover and motor fixing plate are sequentially engaged in one side of the cylinder, and a rear cover and a gear box are sequentially engaged in the other side of the same, and an exhaust port is connected with the latter part pump.
- The one-way valve includes a valve guide installed in a wall surface of the cover opposite to the inlet of the bypass path, a valve member movable based on a guide of a valve guide for opening and closing the inlet of the bypass path an opposite direction with respect to the valve guide, an elastic member disposed between the valve member and the valve guide for generating a certain elastic force in order for the valve member to closely contact with the inlet of the bypass path, and an O-ring formed in a contact surface of the valve member.
- In addition, in the present invention, a motor housing is engaged to one side of the motor fixing plate, and a can housing is engaged in such a manner that the interior of the motor housing is sealed, and a stator is installed in the interior of the can housing, and a motor rotor is fixed in an outer surface of the rotary shaft in such a manner that the motor rotor is protruded to the outside of the motor fixing plate for thereby implementing a good sealing state and an easier attaching and detaching operation of the motor.
- The present invention will become better understood with reference to the accompanying drawings which are given only by way of illustration and thus are not limitative of the present invention, wherein;
- FIG. 1 is a view illustrating an example of use of a conventional roots vacuum pump;
- FIG. 2 is a cross-sectional view illustrating a roots vacuum pump according to the present invention;
- FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2;
- FIG. 4 is a cross-sectional view taken along line B-B of FIG. 2;
- FIG. 5 is a cross-sectional view taken along line C-C of FIG. 2; and
- FIGS. 6 and 7 are views illustrating an operation state of a valve adapted to a roots vacuum pump according to the present invention.
- The embodiments of the present invention will be explained with reference to the accompanying drawings.
- In the drawings,
reference numeral 1 represents a cylinder of a roots pump, and asuction port 11 and anexhaust port 12 are formed in the upper and lower sides of thecylinder 1, and a pair ofrotors 13 are installed in the interior of thecylinder 1 and are supported by arotary shaft 56. - As the
rotors 13 are engaged each other and are rotated, a gas is sucked from a vacuum facility through thesuction port 11 and is exhausted to the side of theexhaust port 12. - In a
canned motor 51, amotor rotor 55 is fixed at an outer surface of therotary shaft 56 protruded to an outer portion of amotor fixing plate 5, and a sealed can housing 53 is formed in the inner side of amotor housing 52. Astator 54 is fixed in the interior of the can housing 53, so that the cannedmotor 51 is easily engaged by engaging themotor housing 52 to themotor fixing plate 5. - Since the can housing53 and the
motor housing 52 are module-engaged, themotor housing 52 is engaged to themotor fixing plate 5 using a bolt for thereby completing an engagement of the motor. It is possible to easily disassembly the motor by separating themotor housing 52 from themotor fixing plate 5. - In addition, a
cooling fan 58 is formed in the latter part of themotor housing 52 for preventing an over-heating of the motor, so that even when the cannedmotor 51 is operated for a long time, it is not over-headed and damaged. A cylindrical can 75 sealingly separates thestator 54 and themotor rotor 55 for thereby implementing a sealed state in the pump. - A
rear cover 3 and agear box 4 are sequentially installed in the other side of thecylinder 1. A gear apparatus is installed in the interior of thegear box 4 for thereby uniformly supplying a driving force to therotors 13. - In the present invention, as a unit for preventing the gas pressure in the side of the
exhaust port 12 of thecylinder 1 from being over-increased, a bypass path is formed in either afront cover 2 or therear cover 3. In this embodiment of the present invention, first andsecond bypass paths front cover 2 and therear cover 3, respectively. - The
first bypass path 21 is formed in the interior of thefront cover 2 for connecting thesuction port 11 and theexhaust port 12, and aninlet 22 of thefirst bypass path 21 communicates with anoutlet 12 of thecylinder 1, and theoutlet 23 of thefirst bypass path 21 communicates with thesuction port 11 of thecylinder 1. - In addition, the
second bypass path 31 is formed in the interior of therear cover 3 for connecting thesuction port 11 and theexhaust port 12, and aninlet 32 of thesecond bypass path 21 communicates with theexhaust port 12, and theoutlet 33 of the same communicates with thesuction port 11 of thecylinder 1. - One-
way valves inlets bypass paths valve guide 62 is installed in a wall surface of thefront cover 2 and therear cover 3 opposite to theinlets second bypass paths closing valve member 63 which is moved along thevalve guide 62 is formed in a portion opposite to thevalve guide 62. Anelastic member 64 is installed between thevalve member 63 and thevalve guide 62 for applying a certain elastic force thereto, so that thevalve member 63 blocks theinlets bypass paths elastic member 64. - An O-
ring 65 is installed in a sealed surface of thevalve member 63, namely, in the wall surface of theinlets valve member 63 blocks theinlets ring 65. - A
filter 71 is formed in the upper wall surface of thegear box 4 for filtering a foreign substance from the oil and gas. An outlet of thefilter 71 is connected with thesecond bypass path 21, and acommunication hole 74 is formed in the contact surface between thegear box 4 and therear cover 3. Aconnection path 74 which connects the interior of thegear box 4 and the interior of themotor fixing plate 5 is formed in an inner wall surface of thecylinder 1 as shown in FIG. 3. Anozzle hole 72 having a certain size which connects the interior of thegear box 4 and thefilter 71 is formed in the wall surface of thegear box 4. - When the vacuum pump apparatus is operated, the air or gas in the interiors of the
motor fixing plate 5 and thegear box 4 is supplied to thefilter 71 through thenozzle hole 72 based on a suction force, and the gas or gas which passes through thefilter 71 is exhausted to thesecond bypass path 31 through thecommunication hole 74, so that the interiors of thegear box 4 and themotor fixing plate 5 maintain a certain vacuum state, whereby an oil lubricating various friction parts is prevented from being polluted by a foreign substance for thereby decreasing an abrasion ratio of the friction parts. - In the drawings,
reference numeral 57 represents a bearing which rotatably supports therotary shaft 56. - The operation of the present invention will be explained.
- When a power is supplied to a root vacuum pump apparatus, and the canned
motor 51 is driven, therotor 13 is rotated, and the gas is sucked from the vacuum facility through thesuction port 11 and is exhausted to the side of theexhaust port 12. The gas exhausted to theexhaust port 12 is sucked by a latter part pump(not shown) and compressed and exhausted to the outside. - At this time, at an initial operation stage of the apparatus, the gas exhausted to the
exhaust port 12 is not fully supplied to the latter part pump side due to a large processing capacity difference between the roots pump and the latter part pump, but remains between theexhaust port 12 and the latter part pump. - As the gas is gradually gathered in the
exhaust port 12, the gas pressure is increased. At the time when the pressure of the gas exceeds the elastic force of theelastic member 64 which elastically supports thevalve member 63, thevalve member 63 compresses theelastic member 64 and moves for thereby opening theinlets second bypass paths - As shown in FIG. 7, the
inlets exhaust port 12 is bypassed to thesuction port 11 of thecylinder 1 through thebypass paths exhaust port 12. - When the gas pressure in the side of the
exhaust port 12 is decreased, thevalve member 63 is forwardly moved by an elastic force of theelastic member 64 for thereby blocking theinlets second bypass paths - When the
valve member 63 blocks theinlets ring 65 closely contacts with theinlets - As the gas is gathered in the side of the
exhaust port 12, whenever the gas pressure is increased, thevalve member 63 is opened, and the gas is recirculated in the direction of thesuction port 11. Therefore, the gas pressure in the side of theexhaust port 12 of thecylinder 1 maintains a certain pressure for thereby preventing a certain damage of the pump and motor. In addition, since the roots vacuum pump and latter part pump are concurrently operated, it is possible to decrease the working time. - In addition, since the bypass paths are formed in the interiors of the front cover and rear cover, respectively, an outer appearance of the roots vacuum pump is good, and the size of the pump is decreased.
- As described above, in the present invention, the bypass paths are formed in the interiors of the front cover and the rear cover for connecting the suction port side and the exhaust port side of the roots pump cylinder. An one-way valve which is automatically opened and closed when an exhaust pressure in the side of the exhaust of the cylinder exceeds a certain reference value is formed in the inlet of the bypass path, so that it is possible to prevent a certain dampage of the pump apparatus and the motor due to the over load by bypassing the remaining compression gas which is not processed by the latter part pump to the side of the roots pump suction port. In addition, in the present invention, since the roots pump and the latter pat pump which have a large capacity difference are concurrently processed, it is possible to significantly decrease the working time, and since the bypass paths are formed in the pump housing, not in the outside of the system, an outer appearance looks good, and the layout of the design is not limited.
- As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.
Claims (3)
1. In a roots vacuum pump apparatus in which a suction port and an exhaust port are formed at both sides of a roots pump cylinder having a pair of rotors which are supported by a rotary shaft and are rotated in an engaged state, a front cover and motor fixing plate are sequentially engaged in one side of the cylinder, and a rear cover and a gear box are sequentially engaged in the other side of the same, and an exhaust port is connected with the latter part pump, a roots vacuum pump apparatus, comprising:
bypass paths formed in at least one inner surface among the inner surfaces of the front cover and the rear cover for communicating the suction pot and exhaust port of the cylinder; and
an one-way valve installed in an inlet of the bypass path contacting with the exhaust port for opening the bypass path when a pressure of the exhaust port exceeds a certain level.
2. The apparatus of claim 1 , wherein said one-way valve includes a valve guide installed in a wall surface of the cover opposite to the inlet of the bypass path, a valve member movable based on a guide of a valve guide for opening and closing the inlet of the bypass path an opposite direction with respect to the valve guide, an elastic member disposed between the valve member and the valve guide for generating a certain elastic force in order for the valve member to closely contact with the inlet of the bypass path, and an 0-ring formed in a contact surface of the valve member.
3. The apparatus of claim 1 , wherein a motor housing is engaged to one side of the motor fixing plate, and a can housing is engaged in such a manner that the interior of the motor housing is sealed, and a stator is installed in the interior of the can housing, and a motor rotor is fixed in an outer surface of the rotary shaft in such a manner that the motor rotor is protruded to the outside of the motor fixing plate for thereby implementing a good sealing state and an easier attaching and detaching operation of the motor.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR2001-48908 | 2001-08-14 | ||
KR10-2001-0048908A KR100408154B1 (en) | 2001-08-14 | 2001-08-14 | Roots vacuum pump |
Publications (1)
Publication Number | Publication Date |
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US20030035738A1 true US20030035738A1 (en) | 2003-02-20 |
Family
ID=19713184
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/962,446 Abandoned US20030035738A1 (en) | 2001-08-14 | 2001-09-26 | Roots vacuum pump |
Country Status (2)
Country | Link |
---|---|
US (1) | US20030035738A1 (en) |
KR (1) | KR100408154B1 (en) |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
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US20040219045A1 (en) * | 2001-10-23 | 2004-11-04 | Masashi Yoshimura | Enclosed mechanical booster |
EP1855009A1 (en) * | 2006-05-11 | 2007-11-14 | Aerzener Maschinenfabrik GmbH | Rotary lobe machine |
CN100416103C (en) * | 2004-06-30 | 2008-09-03 | 海巴(巴拿马)鼓风机公司 | High pressure roots blower |
US20090047142A1 (en) * | 2006-01-31 | 2009-02-19 | Ebara Densan Ltd. | Vacuum pump unit |
US20110037353A1 (en) * | 2008-04-18 | 2011-02-17 | Randax Oy | Method for manufacturing the frame of an electric machine, an electric machine and a frame of an electric machine |
CN102979730A (en) * | 2012-10-26 | 2013-03-20 | 南通龙鹰真空泵业有限公司 | Roots pump |
TWI467094B (en) * | 2011-02-03 | 2015-01-01 | Ulvac Kiko Inc | Vacuum pump |
GB2520140A (en) * | 2013-09-13 | 2015-05-13 | Agilent Technologies Inc | Multi-stage Pump Having Reverse Bypass Circuit |
CN105626535A (en) * | 2016-02-29 | 2016-06-01 | 芜湖环球汽车配件有限公司 | Low-noise vacuum pump |
CN105697374A (en) * | 2014-12-16 | 2016-06-22 | 大卫·金 | Roots pump with improved structure |
CN107724158A (en) * | 2017-11-07 | 2018-02-23 | 中联西北工程设计研究院有限公司 | A kind of low energy consumption zero-emission carrying roller machine frequency conversion vacuum environment friendly system |
WO2022229652A3 (en) * | 2021-04-30 | 2023-02-09 | Edwards Limited | Stator for a vacuum pump |
Families Citing this family (1)
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KR101385954B1 (en) | 2012-11-14 | 2014-04-16 | 데이비드 김 | Multistage dry vacuum pump |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
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JPH055492A (en) * | 1991-06-28 | 1993-01-14 | Matsushita Electric Ind Co Ltd | Fluid rotary device |
JPH05296171A (en) * | 1992-04-13 | 1993-11-09 | Ulvac Japan Ltd | Shaft seal mechanism for positive displacement vacuum pump without using sealing fluid |
JP3134929B2 (en) * | 1999-06-03 | 2001-02-13 | 株式会社モリタエコノス | Multi-stage roots type vacuum pump type suction device |
-
2001
- 2001-08-14 KR KR10-2001-0048908A patent/KR100408154B1/en active IP Right Grant
- 2001-09-26 US US09/962,446 patent/US20030035738A1/en not_active Abandoned
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
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US20040219045A1 (en) * | 2001-10-23 | 2004-11-04 | Masashi Yoshimura | Enclosed mechanical booster |
CN100416103C (en) * | 2004-06-30 | 2008-09-03 | 海巴(巴拿马)鼓风机公司 | High pressure roots blower |
US8251678B2 (en) * | 2006-01-31 | 2012-08-28 | Ebara Corporation | Vacuum pump unit |
US20090047142A1 (en) * | 2006-01-31 | 2009-02-19 | Ebara Densan Ltd. | Vacuum pump unit |
US7510381B2 (en) | 2006-05-11 | 2009-03-31 | Aerzener Mashinenfabrik Gbbh | Lubricating system for a rotary compressor |
EP1855009A1 (en) * | 2006-05-11 | 2007-11-14 | Aerzener Maschinenfabrik GmbH | Rotary lobe machine |
US20070274851A1 (en) * | 2006-05-11 | 2007-11-29 | Aerzener Maschinenfabrik Gmbh | Rotary piston machine |
US20110037353A1 (en) * | 2008-04-18 | 2011-02-17 | Randax Oy | Method for manufacturing the frame of an electric machine, an electric machine and a frame of an electric machine |
CN102084577A (en) * | 2008-04-18 | 2011-06-01 | 兰达克斯有限公司 | A method for manufacturing the frame of an electric machine, an electric machine and a frame of an electric machine |
TWI467094B (en) * | 2011-02-03 | 2015-01-01 | Ulvac Kiko Inc | Vacuum pump |
CN102979730A (en) * | 2012-10-26 | 2013-03-20 | 南通龙鹰真空泵业有限公司 | Roots pump |
GB2520140A (en) * | 2013-09-13 | 2015-05-13 | Agilent Technologies Inc | Multi-stage Pump Having Reverse Bypass Circuit |
CN105697374A (en) * | 2014-12-16 | 2016-06-22 | 大卫·金 | Roots pump with improved structure |
CN105626535A (en) * | 2016-02-29 | 2016-06-01 | 芜湖环球汽车配件有限公司 | Low-noise vacuum pump |
CN107724158A (en) * | 2017-11-07 | 2018-02-23 | 中联西北工程设计研究院有限公司 | A kind of low energy consumption zero-emission carrying roller machine frequency conversion vacuum environment friendly system |
WO2022229652A3 (en) * | 2021-04-30 | 2023-02-09 | Edwards Limited | Stator for a vacuum pump |
Also Published As
Publication number | Publication date |
---|---|
KR100408154B1 (en) | 2003-12-01 |
KR20030015422A (en) | 2003-02-25 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: WOOSUNG VACUUM CO., LTD., KOREA, REPUBLIC OF Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KIM, DEOK-KYEOM;REEL/FRAME:012209/0554 Effective date: 20010905 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |