US20020017282A1 - Pressure control valve and evaporation fuel discharge control device - Google Patents
Pressure control valve and evaporation fuel discharge control device Download PDFInfo
- Publication number
- US20020017282A1 US20020017282A1 US09/769,267 US76926701A US2002017282A1 US 20020017282 A1 US20020017282 A1 US 20020017282A1 US 76926701 A US76926701 A US 76926701A US 2002017282 A1 US2002017282 A1 US 2002017282A1
- Authority
- US
- United States
- Prior art keywords
- valve
- pressure
- port
- fuel
- passage
- 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.)
- Granted
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K17/00—Safety valves; Equalising valves, e.g. pressure relief valves
- F16K17/18—Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on either side
- F16K17/19—Equalising valves predominantly for tanks
- F16K17/196—Equalising valves predominantly for tanks spring-loaded
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
- B60K15/00—Arrangement in connection with fuel supply of combustion engines or other fuel consuming energy converters, e.g. fuel cells; Mounting or construction of fuel tanks
- B60K15/03—Fuel tanks
- B60K15/035—Fuel tanks characterised by venting means
- B60K15/03504—Fuel tanks characterised by venting means adapted to avoid loss of fuel or fuel vapour, e.g. with vapour recovery systems
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
- B60K15/00—Arrangement in connection with fuel supply of combustion engines or other fuel consuming energy converters, e.g. fuel cells; Mounting or construction of fuel tanks
- B60K15/03—Fuel tanks
- B60K15/035—Fuel tanks characterised by venting means
- B60K15/03519—Valve arrangements in the vent line
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K24/00—Devices, e.g. valves, for venting or aerating enclosures
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
- B60K15/00—Arrangement in connection with fuel supply of combustion engines or other fuel consuming energy converters, e.g. fuel cells; Mounting or construction of fuel tanks
- B60K15/03—Fuel tanks
- B60K2015/03256—Fuel tanks characterised by special valves, the mounting thereof
- B60K2015/03296—Pressure regulating valves
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/7722—Line condition change responsive valves
- Y10T137/7771—Bi-directional flow valves
- Y10T137/7772—One head and seat carried by head of another
- Y10T137/7774—Supporting valve spring carried by supporting valve
- Y10T137/7775—Spring stop on supported valve stem
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/7722—Line condition change responsive valves
- Y10T137/7771—Bi-directional flow valves
- Y10T137/7772—One head and seat carried by head of another
- Y10T137/7774—Supporting valve spring carried by supporting valve
- Y10T137/7776—Spring abuts guide for supported valve stem
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/7722—Line condition change responsive valves
- Y10T137/7771—Bi-directional flow valves
- Y10T137/778—Axes of ports co-axial
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/8593—Systems
- Y10T137/86928—Sequentially progressive opening or closing of plural valves
- Y10T137/87016—Lost motion
- Y10T137/8704—First valve actuates second valve
Definitions
- the present invention relates to a pressure control valve. Further, the present invention relates an evaporation fuel discharge control device which, when fuel is supplied to a fuel tank of a car, is used to control the discharge of evaporation fuel from the fuel tank.
- evaporation fuel from a fuel tank is temporarily stored in a canister through an evapo-pipe, and it is introduced into an engine suitably. There is disposed a pressure control valve.
- FIG. 17 shows the pressure control valve that is disclosed in the above-cited publication. That is, the present pressure control valve comprises a cap 202 which includes a first port 201 in communication with a fuel tank, and a body 204 including a second port 203 in communication with a canister.
- the body 204 includes a partition wall 205 in the interior portion thereof; and, in particular, between the upper surface of the partition wall 205 and the inner surface of the cap 202 , there is interposed a first valve 206 , and, inside the first valve 206 , in particular, between the upper surface of the partition wall 205 and a valve body 207 , there is interposed a second valve 208 .
- evaporation fuel discharge control device which, when fuel is supplied to a fuel tank of a car, is used to control the discharge of evaporation fuel from the fuel tank
- a device which is disclosed in Japanese Patent Publication No. Hei. 8-189423.
- FIG. 18 shows the evaporation fuel discharge control device disclosed in the above-cited patent publication.
- a tank main body 302 of a fuel tank 301 is connected to a canister 303 through an evaporation fuel passage 304 .
- a float valve 306 which is used to close an entrance portion 305 of the evaporation fuel passage 304 when fuel within the tank main body 302 exceeds a given liquid level.
- the switch valve assembly 307 has a diaphragm valve which divides a positive pressure chamber 307 a and a back pressure chamber 307 b, while the evaporation fuel passage 304 includes the positive pressure chamber 307 a.
- the portion of the evaporation fuel passage 304 on the upstream side of the switch valve assembly 307 is connected to the pressure introduction passage 309 by a communicating passage 310 .
- a check valve 311 which is structured such that it can be opened when the pressure on the upstream side of the switch valve assembly 307 is higher by a given value or more than the pressure on the pressure introduction passage 309 side.
- the evaporation fuel discharge control device of this type if a cap (not shown) of the fuel supply pipe is removed when starting fuel supply, then the pressure on the back pressure chamber 307 b side of the switch valve assembly 307 is reduced down by the predetermined value or more than the pressure on the positive pressure chamber 307 a side of the switch valve assembly 307 through the pressure introduction passage 309 to thereby open the switch valve assembly 307 , so that the evaporation fuel from the tank main body 302 is fed through the evaporation fuel passage 304 and is stored to the canister 303 .
- the pressure of the entrance portion 308 a of the fuel supply pipe 308 increases together with and equally to the pressure of the interior portion of the tank main body 302 , so that the pressure on the back pressure chamber 307 b side of the switch valve assembly 307 is caused to increase through the pressure introduction passage 309 and the pressure of the check valve 311 on the pressure introduction passage 309 side thereof is also caused to increase.
- the float valve 306 is divided in two upper and lower stages.
- the float valve 306 is complicated in structure, the manufacturing cost thereof is increased, and the response property thereof is lowered.
- the present invention aims at the above-mentioned problems found in the conventional pressure control valve. Accordingly, it is an object of the invention to provide a pressure control valve which, when the pressure on the first port side increases suddenly, can flow a large quantity of fluid to the second port side.
- a pressure control valve In the pressure control valve, a casing has a first port formed on a first side of the casing, a second port formed on a second side.
- a positive pressure valve is disposed in the casing, the positive pressure valve moving to a side of the second port to thereby communicating with the side of the second port when a pressure on a side of the first port becomes higher than the side of the second port.
- a negative pressure valve is disposed in the casing, the negative pressure valve moving to the side of the first port to thereby communicating with the side of the second port when the pressure on the side of the first port becomes lower than the side of the second port.
- flow passage expanding means is provided which, when the positive pressure valve has moved to the side of the second port beyond a given distance, allows the side of the first port to communicate with the side of the second port by opening the negative pressure valve.
- the positive pressure valve is formed as a cylindrical-shaped bottomed valve having an opening on the bottom of the first port.
- the negative pressure valve has a rod portion extending through a bottom surface portion of the positive pressure valve, a valve portion stored within the positive pressure valve and connected to a first end of the rod portion, and an energizing portion connected to a second end of the rod portion for energizing the rod portion to the side of the second port.
- a projecting portion is formed which, when the positive pressure valve has moved to the side of the second port beyond a given distance, can be contacted with the energizing portion of the negative pressure valve to thereby allow the negative pressure valve to communicate with the side of the second port.
- the first port can be connected to a fuel tank, whereas the second port can be connected to a canister.
- an evaporation fuel discharge control device for adsorbing evaporation fuel from a fuel tank has a tank main body with a fuel supply pipe, an evaporation fuel passage for connecting the tank main body and the canister, and a float valve is disposed within the tank main body for closing an entrance portion of the evaporation fuel passage when fuel within the tank main body exceeds a given liquid level.
- a switch valve includes a positive pressure chamber and a back pressure chamber, the evaporation fuel passage being disposed on a side of the positive pressure chamber, and the switch valve is structured such that it can be opened when a pressure on the side of the positive pressure chamber is higher by a predetermined value or more than a pressure on a side of the back pressure chamber.
- a pressure introduction passage for connecting an entrance portion of the fuel supply pipe to the back pressure chamber of the switch valve is provided.
- First communicating means allows an upstream side of the switch valve to communicate with the pressure introduction passage when a pressure on the upstream side of the switch valve is higher by a given value or more than a pressure on a side of the pressure introduction passage.
- Second communicating means allows the upstream side of the switch valve to communicate with the pressure introduction passage when the pressure on the side of the pressure introduction passage is higher by a given value or more than the pressure on the upstream side of the switch valve.
- the first and second communicating means include a positive pressure valve and a negative pressure valve to be stored within a valve chamber which is formed integrally with the switch valve, and the negative pressure valve is disposed in the positive pressure valve.
- the evaporation fuel discharge control device further includes passage expansion means disposed so as to be opposed to the pressure introduction passage and capable of opening the negative pressure valve when the positive pressure valve is moved beyond a given distance toward an opening of the pressure introduction passage, the opening of the pressure introduction passage being opened in the valve chamber.
- an evaporation fuel discharge control device on completion of fuel supply, if the cap is mounted on the fuel supply pipe, then the pressure of the entrance portion of the fuel supply pipe increases up to the same level as the pressure within the tank main body, and thus the second communicating means is opened through the pressure introduction passage to thereby increase the pressure on the upstream side of the switch valve up to almost the same level as the pressure within the tank main body, thereby removing the sticking of the float valve to the entrance portion of an evaporation fuel passage.
- the positive pressure valve of the first communicating means and the negative pressure valve of the second communicating means are stored within the valve chamber which is formed integrally with the switch valve, and the negative pressure valve is disposed in the positive pressure valve.
- FIG. 1 is a longitudinal section view of an embodiment of a pressure control valve according to the invention.
- FIG. 2 is a transverse section view of the pressure control valve shown in FIG. 1, taken along the line II-II shown in FIG. 1;
- FIG. 3 is a transverse section view of the pressure control valve shown in FIG. 1, taken along the line III-III shown in FIG. 1;
- FIG. 4 is a longitudinal section view of the pressure control valve shown in FIG. 1, showing a positive pressure state thereof;
- FIG. 5 is a longitudinal section view of the pressure control valve shown in FIG. 1, showing a negative pressure state thereof;
- FIG. 6 is a longitudinal section view of the pressure control valve shown in FIG. 1, showing a state thereof in which the positive pressure thereof increases suddenly;
- FIG. 7 is an explanatory view of a pipe arrangement system employed in an embodiment of an evaporation fuel discharge control device according to the invention.
- FIG. 8 is an enlarged section view of the main portions of the evaporation fuel discharge control device shown in FIG. 7;
- FIG. 9 is an enlarged section view of a valve chamber employed in the evaporation fuel discharge control device shown in FIG. 7;
- FIG. 10 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof in a car normal running operation;
- FIG. 11 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof when a cap is removed;
- FIG. 12 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof when fuel is supplied;
- FIG. 13 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof when fuel is supplied;
- FIG. 14 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof when the tank is full;
- FIG. 15 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof when the cap is mounted;
- FIG. 16 is an explanatory view of a pipe arrangement system employed in another embodiment of an evaporation fuel discharge control device according to the invention.
- FIG. 17 is a longitudinal section view of a conventional pressure control valve
- FIG. 18 is an explanatory view of a pipe arrangement system employed in a conventional evaporation fuel discharge control device.
- FIGS. 1 to 3 respectively show an embodiment of a pressure control valve according to the invention.
- a pressure control valve according to the present embodiment is disposed in an evapo-pipe which is used to connect together the fuel tank and canister of a car.
- a casing 11 includes on one side thereof a first pipe conduit portion 13 , while the interior portion of the first pipe conduit portion 13 is used as a first port 15 .
- the casing 11 includes on the other side thereof a second pipe conduit portion 17 , while the interior portion of the second pipe conduit portion 17 is used as a second port 19 .
- the casing 11 comprises a cylindrical-shaped portion 21 with which the first pipe conduit portion 13 is formed integrally, and a cover portion 23 with which the second pipe conduit portion 17 is formed integrally.
- the casing 11 can be produced by connecting together the cylindrical-shaped portion 21 and cover portion 23 by ultrasonic welding or by other means.
- a positive pressure valve 25 structured such that, when the pressure on the first port 15 side becomes high, it can be moved toward the second port 19 side to thereby allow the first port 15 side to communicate with the second port 19 side.
- a negative pressure valve 27 structured such that, when the pressure on the first port 15 side becomes low, it can be moved toward the first port 15 side to thereby allow the second port 19 to communicate with the first port 15 side.
- the cylindrical-shaped portion 21 comprises a small diameter portion 21 a and a large diameter portion 21 b, while a valve portion 25 a of the positive pressure valve 25 is situated in the small diameter portion 21 a of the cylindrical-shaped portion 21 .
- a stepped portion 21 c between the first pipe conduit portion 13 and small diameter portion 21 a, and, in the stepped portion 21 c, there is formed a positive pressure seal surface 21 d. If the valve portion 25 a of the positive pressure valve 25 is contacted with the positive pressure seal surface 21 d, then the sealing operation to be executed by the positive pressure valve 25 can be attained.
- This guide portion 25 b is formed integrally with the valve portion 25 a.
- a stepped portion 25 c Between the valve portion 25 a and guide portion 25 b of the positive pressure valve 25 , there is formed a stepped portion 25 c; and, between the stepped portion 25 c and cover portion 23 , there is disposed a coiled spring 29 which is used to energize the positive pressure valve 25 toward the first port 15 side.
- the positive pressure valve 25 is formed in a cylindrical-shaped bottomed valve which includes a passage portion.
- a rod portion 27 a of the negative pressure valve 27 is inserted through the bottom surface portion 25 d of the positive pressure valve 25 .
- the rod portion 27 a is structured such that, as shown in FIG. 3, it has a cross-shaped section in a sectional view.
- a valve portion 27 b of the negative pressure valve 27 On the first port 15 side of the rod portion 27 a, there is arranged a valve portion 27 b of the negative pressure valve 27 in such a manner that it is formed integrally with the rod portion 27 a.
- valve portion 27 b of the negative pressure valve 27 is stored within the valve portion 25 a of the positive pressure valve 25 .
- the outside diameter of the valve portion 27 b of the negative pressure valve 27 is set smaller than the inside diameter of the valve portion 25 a of the positive pressure valve 25 and, between the valve portion 27 b and 25 a, there is formed a passage portion L 3 .
- a negative pressure seal surface 25 e Between the valve portion 25 a and bottom surface portion 25 d of the positive pressure valve 25 , there is formed a negative pressure seal surface 25 e. That is, if the valve portion 27 b of the negative pressure valve 27 is contacted with the negative pressure seal surface 25 e, then a sealing operation to be executed by the negative pressure valve 27 can be accomplished.
- An energizing portion 31 which is used to energize the rod portion 27 a of the negative pressure valve 27 toward the second port 19 side, is fixed to the other end of the rod portion 27 a by thermal welding or by other means.
- a coiled spring 33 which is used to energize the energizing portion 31 toward the second port 19 side.
- projecting portions 23 a which, when the positive pressure valve 25 has moved toward the second port side 19 beyond a given distance, can be contacted with the energizing portion 31 of the negative pressure valve 27 to thereby allow the first port side to communicate with the second port 19 side by opening the negative pressure valve 27 .
- the projecting portions 23 a are provided on and formed integrally with the inner surface of the cover portion 23 at a given angle from the center of the cover portion 23 , for example, at six positions of the cover portion 23 inner surface.
- the present pressure control valve is structured such that, when the positive pressure valve 25 has moved to the second port 19 side beyond a given distance, the first port 15 side is allowed to communicate with the second port 19 side by opening the negative pressure valve 27 . Thanks to this, if the pressure on the first port 15 side increases suddenly, then the positive pressure valve 25 is moved to the second port 19 side beyond a given distance, and the negative pressure valve 27 is thereby allowed to communicate with the second port 19 side, so that the fluid or fuel from the first port 15 is allowed to flow to the second port 19 through the respective flow passages of the positive and negative pressure valves 25 and 27 .
- the flow passage expanding means can be structured easily and positively.
- FIG. 7 shows an embodiment of an evaporation fuel discharge control device according to the invention.
- reference character 121 designates a fuel tank.
- This fuel tank 121 comprises a tank main body 123 and a fuel supply pipe 125 .
- volatile fuel such as gasoline, light oil or the like.
- a cap 125 is mounted on the entrance portion 125 a of the fuel supply pipe 125 .
- reference character 129 designates a canister which is used to adsorb evaporation fuel from the fuel tank 121 .
- the evaporation fuel passage 131 is opened on the upper surface of the tank main body 123 through a switch valve 133 .
- the switch valve 133 is a diaphragm valve which includes a diaphragm 137 within a valve main body 135 thereof.
- valve main body 135 of the switch valve 133 is divided by the diaphragm 137 to thereby form a positive pressure chamber 139 and a back pressure chamber 141 .
- a passage 145 which is connected through a pipe 143 to the canister 129 and forms part of the evaporation fuel passage 131 .
- the passage 145 is bent toward the diaphragm 137 side and includes a valve seat 145 a on the diaphragm 137 side end thereof.
- a coiled spring 147 which energizes the diaphragm 137 toward the valve seat 145 a of the passage 145 .
- the switch valve 133 is structured such that it can be opened when the pressure on the positive pressure chamber 139 side is higher by a predetermined value or more than the pressure on the back pressure chamber 141 side, whereas it is closed in other pressure conditions.
- a float valve 149 On the lower surface of the valve main body 135 of the switch valve 133 , there is disposed a float valve 149 .
- the float valve 149 includes a cylindrical-shaped guide portion 151 which is formed integrally with the valve main body 135 , and a float 153 which is to be stored within the guide portion 151 .
- the float 153 is energized upwardly by a coiled spring 155 .
- the flange portion 157 of the float valve 149 is fixed to the upper surface of the tank main body 123 , with the guide portion 151 of the float valve 149 inserted through a through hole 123 a which is formed in the tank main body 123 .
- the guide portion 151 of the float valve 149 is separated from the positive pressure chamber 139 of the switch valve 133 by a partition portion 159 which is formed integrally with the valve main body 135 of the switch valve 133 .
- a valve chamber 163 is formed integrally with the valve main body 135 .
- valve chamber 163 there is opened a pressure introduction passage 165 which is in communication with the entrance portion 125 a of the fuel supply pipe 125 .
- valve chamber 163 is allowed to be in communication with the back pressure chamber 141 side of the switch valve 133 .
- valve chamber 163 there are disposed a positive pressure valve 173 forming first communicating means and a negative pressure valve 175 forming second communicating means.
- the positive pressure valve 173 allows the positive pressure chamber 139 side of the switch valve 133 to communicate with the pressure introduction passage 165 when the pressure on the positive pressure chamber 139 side is higher by a given value or more than the pressure on the pressure introduction passage 165 .
- the negative pressure valve 175 allows the entrance portion 161 of the evaporation fuel passage 131 to communicate with the pressure introduction passage 165 when the pressure on the pressure introduction passage 165 is higher by a given value or more than the pressure of the entrance portion 161 .
- valve main body 173 a of the positive pressure valve 173 is energized toward the partition portion 177 by a coiled spring 179 and, if the valve main body 173 a is contacted with the partition portion 177 , then the positive pressure valve 173 is closed.
- valve main body 173 a of the positive pressure valve 173 at a position thereof which is located outward in the diameter direction of the through hole 173 c, there is disposed a cylindrical-shaped valve main body 175 a of the negative pressure valve 175 .
- valve main body 175 a of the negative pressure valve 175 is energized toward a passage 167 side by a coiled spring 181 and, if the valve main body 175 a is contacted with the bottom surface 173 b, then the negative pressure valve 175 is closed.
- the projecting portions 163 a are respectively formed at an angle of, for example, 60° with the passage 167 between them and, when the positive pressure valve 173 moves beyond a given distance toward the passage 167 side, the projecting portions 163 a are butted against the energizing portion 175 b of the negative pressure valve 175 .
- reference character 183 designates an evaporation fuel passage which is used to introduce the evaporation fuel within the fuel tank 121 to the canister 129 in other operations than in the fuel supply operation.
- the pressure on the upstream side (positive pressure chamber 139 side) of the switch valve 133 becomes higher by a predetermined value or more than the pressure on the pressure introduction passage 165 side of the positive pressure valve 173 to thereby open the positive pressure valve 173 , so that a part of the evaporation fuel within the tank main body 123 is introduced to the entrance portion 125 a of the fuel supply pipe 125 , and the evaporation fuel is returned back to the interior portion of the tank main body 123 together with the fuel that is supplied from the fuel supply gun or the like.
- the positive pressure valve 173 when the fuel is supplied in a high flow amount, the positive pressure valve 173 is moved beyond a given distance toward the passage 167 side due to the high pressure caused by the high flow amount of fuel supply, so that the energizing portion 175 b of the positive pressure valve 175 is butted against the projecting portions 163 a to thereby open the negative pressure valve 175 .
- the area of the passage is widened and thus, in the high flow amount of fuel supply, the circulating flow amount of the evaporation fuel toward the entrance portion 125 a of the fuel supply pipe 125 increases to thereby reduce the amount of the air that is introduced into the tank main body 123 from the entrance portion 125 a of the fuel supply pipe 125 .
- the present evaporation fuel discharge control device can prevent easily and positively the float valve 149 from sticking to the entrance portion 161 of the evaporation fuel passage 131 .
- the positive pressure valve 173 forming the first communicating means and the negative pressure valve 175 forming the second communicating means are respectively stored within the valve chamber 163 which is formed integrally with the switch valve 133 , while the negative pressure valve 175 is disposed in the positive pressure valve 173 . Therefore, the first and second communicating means can be structured without using pipes which are provided separately, so that the present evaporation fuel discharge control device can be made compact.
- the circulating flow amount of the evaporation fuel toward the entrance portion 125 a of the fuel supply pipe 125 is increased, thereby being able to reduce the amount of the fresh air that could be otherwise taken into the tank main body 123 from the entrance portion 125 a of the fuel supply pipe 125 .
- This in turn can reduce the generation of vapor and also can reduce the size of the canister 129 .
- FIG. 16 shows another embodiment of an evaporation fuel discharge control device according to the invention and, in this embodiment, a tank main body 123 and a canister 129 are connected to each other through an evaporation fuel passage 131 .
- a float valve 149 which is capable of closing the entrance portion 161 of the evaporation fuel passage 131 when the fuel within the tank main body 123 exceeds a given liquid level.
- a switch valve 133 which comprises a diaphragm valve.
- the present switch valve 133 divides a positive pressure chamber 139 and a back pressure chamber 141 , while the evaporation fuel passage 131 includes the positive pressure chamber 139 side of the switch valve 133 .
- a pressure introduction passage 165 in such a manner that it connects the entrance portion 125 a of the fuel supply pipe 125 to the back pressure chamber 141 side of the switch valve 133 .
- first communicating means 101 which allows the upstream side of the switch valve 133 to communicate with the pressure introduction passage 165 when the pressure on the upstream side of the switch valve 33 is higher by a given value or more than the pressure on the pressure introduction passage 165 side thereof.
- the first communicating means 101 includes a first communicating passage 103 which connects the upstream side of the switch valve 133 in the evaporation fuel passage 131 to the pressure introduction passage 165 .
- a first check valve 105 which can be opened when the pressure on the upstream side of the switch valve 133 is higher by a given value or more than the pressure on the pressure introduction passage 165 side.
- a second communicating means 107 which allows the upstream side of the switch valve 133 to communicate with the pressure introduction passage 165 when the pressure on the pressure introduction passage 165 side is higher by a given value or more than the pressure on the upstream side of the switch valve 133 .
- the second communicating means 107 includes a second communicating passage 109 which connects the upstream side of the switch valve 133 in the evaporation fuel passage 131 to the pressure introduction passage 165 .
- a second check valve 111 which can be opened when the pressure on the pressure introduction passage 165 side is higher by a given value or more than the pressure on the upstream side of the switch valve 133 .
- the first check valve 105 of the first communicating means 101 is closed, which can eliminate the possibility that the evaporation fuel can be introduced to the entrance portion 125 a of the fuel supply pipe 125 through the pressure introduction passage 165 and discharged externally therefrom.
- the pressure on the upstream side (positive pressure chamber 139 side) of the switch valve 133 becomes higher by a predetermined value or more than the pressure on the pressure introduction passage 165 side of the check valve 105 disposed in the first communicating means 101 to thereby open the check valve 105 of the first communicating means 101 , so that the evaporation fuel within the tank main body 123 is introduced to the entrance portion 125 a of the fuel supply pipe 125 , and the evaporation fuel is returned back to the interior portion of the tank main body 123 together with the fuel that is supplied from a fuel supply gun 113 or the like.
- a pressure control valve since there is formed the flow passage expanding means which, when the positive pressure valve has moved to the second port side beyond a given distance, allows the first port side to communicate with the second port side, if the pressure on the first port side increases suddenly, then the positive pressure valve is moved to the second port side beyond a given distance to thereby allow the firs port side to communicate with the second port side, so that the fluid or fuel from the first port side is allowed to flow to the second port through the respective flow passages of the positive and negative pressure valves.
- the flow passage expanding means can be structured easily and positively.
- an evaporation fuel discharge control device on completion of oil supply, if the cap is mounted on the fuel supply pipe, then the pressure of the entrance portion of the fuel supply pipe increases up to the same level as the pressure within the tank main body, and thus the second communicating means is opened through the pressure introduction passage to thereby increase the pressure on the upstream side of the switch valve up to almost the same level as the same level as the pressure within the tank main body, thereby being able to remove the sticking of the float valve to the entrance portion of an evaporation fuel passage. That is, the present evaporation fuel discharge control device is able to prevent easily and positively the float valve from sticking to the entrance portion of the evaporation fuel passage.
- the first and second communicating means can be structured without using a separately provided pipe, which makes it possible to make compact the present evaporation fuel discharge control device.
- the negative pressure valve can be opened and the area of the passage toward the pressure introduction passage can be expanded by the passage expanding means and, therefore, in the high flow rate of fuel supply, the flow rate of the circulating evaporation fuel toward the entrance portion side of the fuel supply pipe is increased to thereby be able to reduce the amount of the fresh air taken into the fuel from the entrance portion of the fuel supply pipe.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Transportation (AREA)
- Supplying Secondary Fuel Or The Like To Fuel, Air Or Fuel-Air Mixtures (AREA)
Abstract
The pressure control valve is structured such that a first port is formed on one side of a casing, a second port is formed on the other side, and, in the casing, there are disposed not only a positive pressure valve which, when the pressure on the first port side becomes high, can be moved to the second port side to thereby communicate with the second port side, but also a negative pressure valve which, when the pressure on the first port side becomes low, can be moved to the first port side to thereby communicate with the second port side. In the pressure control valve, there is provided flow passage expanding means which, which the positive pressure valve has moved to the second port side beyond a given distance, allows the first port side to communicate with the second port side. Further, the evaporation fuel discharge control device comprises first communicating means which allows the upstream side of a switch valve to communicate with an pressure introduction passage when the pressure on the upstream side of the switch valve is higher by a given value or more than the pressure on the pressure introduction passage side, and second communicating means which allows the upstream side of the switch valve to communicate with the pressure introduction passage when the pressure on the pressure introduction passage side is higher by a given value or more than the pressure on the upstream side of the switch valve.
Description
- 1. Field of the Invention
- The present invention relates to a pressure control valve. Further, the present invention relates an evaporation fuel discharge control device which, when fuel is supplied to a fuel tank of a car, is used to control the discharge of evaporation fuel from the fuel tank.
- The present application is based on Japanese Patent Applications No. Hei. 10-106055 and 11-59674 which are incorporated herein by reference.
- 2. Description of the Related Art
- Generally, in a car, evaporation fuel from a fuel tank is temporarily stored in a canister through an evapo-pipe, and it is introduced into an engine suitably. There is disposed a pressure control valve.
- And, conventionally, as a pressure control valve which is used in such pipe, for example, there is known a pressure control valve which is disclosed in Japanese Utility Model Publication No. Hei. 1-83976.
- FIG. 17 shows the pressure control valve that is disclosed in the above-cited publication. That is, the present pressure control valve comprises a
cap 202 which includes afirst port 201 in communication with a fuel tank, and abody 204 including a second port 203 in communication with a canister. - The
body 204 includes apartition wall 205 in the interior portion thereof; and, in particular, between the upper surface of thepartition wall 205 and the inner surface of thecap 202, there is interposed afirst valve 206, and, inside thefirst valve 206, in particular, between the upper surface of thepartition wall 205 and a valve body 207, there is interposed asecond valve 208. - And, in the portion of the
partition wall 205 that is situated on the inner side of thesecond valve 208, there is formed afluid passage 209. - However, in the above-structured conventional pressure control valve, since the
fluid passage 209 is formed only in the portion of thepartition wall 205 that is situated on the inner side of thesecond valve 208, when the pressure within the fuel tank increases suddenly, it is difficult to introduce the evaporation fuel within the fuel tank through the first andsecond ports 201 and 203 to the canister side quickly. - Further, as an evaporation fuel discharge control device which, when fuel is supplied to a fuel tank of a car, is used to control the discharge of evaporation fuel from the fuel tank, for example, there is known a device which is disclosed in Japanese Patent Publication No. Hei. 8-189423.
- Now, FIG. 18 shows the evaporation fuel discharge control device disclosed in the above-cited patent publication. In this evaporation fuel discharge control device, a tank
main body 302 of afuel tank 301 is connected to acanister 303 through anevaporation fuel passage 304. - Within the tank
main body 302, there is disclosed afloat valve 306 which is used to close anentrance portion 305 of theevaporation fuel passage 304 when fuel within the tankmain body 302 exceeds a given liquid level. - And, in the
evaporation fuel passage 304, there is disposed aswitch valve assembly 307. - The
switch valve assembly 307 has a diaphragm valve which divides a positive pressure chamber 307 a and a back pressure chamber 307 b, while theevaporation fuel passage 304 includes the positive pressure chamber 307 a. - And, when the pressure on the positive pressure chamber307 a side is higher by a predetermined value or more than the pressure on the back pressure chamber 307 b side, the
evaporation fuel passage 304 is opened. - On the back pressure chamber307 b side of the
switch valve assembly 307, there is opened a pressure introduction passage 309 which is connected to an entrance portion 308 a of afuel supply pipe 308. - And, the portion of the
evaporation fuel passage 304 on the upstream side of theswitch valve assembly 307 is connected to the pressure introduction passage 309 by a communicatingpassage 310. - In the communicating
passage 310, there is disposed acheck valve 311 which is structured such that it can be opened when the pressure on the upstream side of theswitch valve assembly 307 is higher by a given value or more than the pressure on the pressure introduction passage 309 side. - In the evaporation fuel discharge control device of this type, if a cap (not shown) of the fuel supply pipe is removed when starting fuel supply, then the pressure on the back pressure chamber307 b side of the
switch valve assembly 307 is reduced down by the predetermined value or more than the pressure on the positive pressure chamber 307 a side of theswitch valve assembly 307 through the pressure introduction passage 309 to thereby open theswitch valve assembly 307, so that the evaporation fuel from the tankmain body 302 is fed through theevaporation fuel passage 304 and is stored to thecanister 303. - And, if the internal pressure of the tank
main body 302 is increased due to start of the fuel supply and the upstream side pressure of theswitch valve assembly 307 is thereby increased by the given value or more than the pressure on the pressure introduction passage 309 of thecheck valve 311, then thecheck valve 311, which is disposed in the communicatingpassage 310, is caused to open. As a result of this, a part of the evaporation fuel within the tankmain body 302 is introduced through the pressure introduction passage 309 into the entrance portion 308 a of thefuel supply pipe 308 and is then returned back into the tankmain body 302 together with fuel which is supplied from afuel supply gun 312. - And, if the tank
main body 302 is filled with fuel, then theentrance portion 305 of theevaporation fuel passage 304 is closed by thefloat valve 306, with the result that the pressure on the upstream side of theswitch valve assembly 307 with the communication thereof with respect to the interior portion of the tankmain body 302 cut off is caused to decrease quickly to thereby close theswitch valve assembly 307 andcheck valve 311. - And, if the cap (not shown) is mounted on the
fuel supply pipe 308 after completion of the fuel supply, then the pressure of the entrance portion 308 a of thefuel supply pipe 308 increases together with and equally to the pressure of the interior portion of the tankmain body 302, so that the pressure on the back pressure chamber 307 b side of theswitch valve assembly 307 is caused to increase through the pressure introduction passage 309 and the pressure of thecheck valve 311 on the pressure introduction passage 309 side thereof is also caused to increase. - However, in the above-mentioned conventional evaporation fuel discharge control device, because, if the interior portion of the tank
main body 302 is filled with the fuel, then not only theentrance portion 305 of theevaporation fuel passage 304 is closed by thefloat valve 306 but also theswitch valve assembly 307 andcheck valve 311 are closed, the pressure on the upstream side of theswitch valve assembly 307 remains as pressure equivalent to the atmospheric pressure, which causes thefloat valve 306 to stick to theentrance portion 305 of theevaporation fuel passage 304. - Therefore, conventionally, in order to prevent the
float valve 306 from sticking to theentrance portion 305 of theevaporation fuel passage 304, for example, thefloat valve 306 is divided in two upper and lower stages. However, in this case, there arise other problems: that is, thefloat valve 306 is complicated in structure, the manufacturing cost thereof is increased, and the response property thereof is lowered. - The present invention aims at the above-mentioned problems found in the conventional pressure control valve. Accordingly, it is an object of the invention to provide a pressure control valve which, when the pressure on the first port side increases suddenly, can flow a large quantity of fluid to the second port side.
- It is another object of the invention to provide an evaporation fuel discharge control device which is able to prevent easily and positively a float valve from sticking to the entrance portion of an evaporation fuel passage.
- In attaining the above objects, according to a first aspect of the present invention, there is provided a pressure control valve. In the pressure control valve, a casing has a first port formed on a first side of the casing, a second port formed on a second side. A positive pressure valve is disposed in the casing, the positive pressure valve moving to a side of the second port to thereby communicating with the side of the second port when a pressure on a side of the first port becomes higher than the side of the second port. A negative pressure valve is disposed in the casing, the negative pressure valve moving to the side of the first port to thereby communicating with the side of the second port when the pressure on the side of the first port becomes lower than the side of the second port. Further, flow passage expanding means is provided which, when the positive pressure valve has moved to the side of the second port beyond a given distance, allows the side of the first port to communicate with the side of the second port by opening the negative pressure valve.
- Preferably, the positive pressure valve is formed as a cylindrical-shaped bottomed valve having an opening on the bottom of the first port. The negative pressure valve has a rod portion extending through a bottom surface portion of the positive pressure valve, a valve portion stored within the positive pressure valve and connected to a first end of the rod portion, and an energizing portion connected to a second end of the rod portion for energizing the rod portion to the side of the second port. Further, on the side of the second port of the casing, a projecting portion is formed which, when the positive pressure valve has moved to the side of the second port beyond a given distance, can be contacted with the energizing portion of the negative pressure valve to thereby allow the negative pressure valve to communicate with the side of the second port.
- Further, the first port can be connected to a fuel tank, whereas the second port can be connected to a canister.
- In the above pressure control valve, if the pressure on the first port side increases suddenly, then the positive pressure valve is moved to the second port side beyond a given distance to thereby allow the negative pressure valve to communicate with the second port side, so that the fluid or fuel from the first port side is allowed to flow to the second port through the respective flow passages of the positive and negative pressure valves.
- Also, if the pressure on the first port side increases suddenly, then the positive pressure valve is moved to the second port side together with the negative pressure valve, and, when the positive pressure valve has moved to the second port side beyond a given distance, the projecting portion formed in the casing is contacted with the energizing portion of the negative pressure valve to thereby allow the negative pressure valve to communicate with the second port side.
- In attaining the above objects, according to a second aspect of the present invention, there is provided an evaporation fuel discharge control device. A canister for adsorbing evaporation fuel from a fuel tank has a tank main body with a fuel supply pipe, an evaporation fuel passage for connecting the tank main body and the canister, and a float valve is disposed within the tank main body for closing an entrance portion of the evaporation fuel passage when fuel within the tank main body exceeds a given liquid level. Further, a switch valve includes a positive pressure chamber and a back pressure chamber, the evaporation fuel passage being disposed on a side of the positive pressure chamber, and the switch valve is structured such that it can be opened when a pressure on the side of the positive pressure chamber is higher by a predetermined value or more than a pressure on a side of the back pressure chamber. A pressure introduction passage for connecting an entrance portion of the fuel supply pipe to the back pressure chamber of the switch valve is provided. First communicating means allows an upstream side of the switch valve to communicate with the pressure introduction passage when a pressure on the upstream side of the switch valve is higher by a given value or more than a pressure on a side of the pressure introduction passage. Second communicating means allows the upstream side of the switch valve to communicate with the pressure introduction passage when the pressure on the side of the pressure introduction passage is higher by a given value or more than the pressure on the upstream side of the switch valve.
- Preferably, the first and second communicating means include a positive pressure valve and a negative pressure valve to be stored within a valve chamber which is formed integrally with the switch valve, and the negative pressure valve is disposed in the positive pressure valve.
- Preferably, the evaporation fuel discharge control device further includes passage expansion means disposed so as to be opposed to the pressure introduction passage and capable of opening the negative pressure valve when the positive pressure valve is moved beyond a given distance toward an opening of the pressure introduction passage, the opening of the pressure introduction passage being opened in the valve chamber.
- In an evaporation fuel discharge control device according to the invention, on completion of fuel supply, if the cap is mounted on the fuel supply pipe, then the pressure of the entrance portion of the fuel supply pipe increases up to the same level as the pressure within the tank main body, and thus the second communicating means is opened through the pressure introduction passage to thereby increase the pressure on the upstream side of the switch valve up to almost the same level as the pressure within the tank main body, thereby removing the sticking of the float valve to the entrance portion of an evaporation fuel passage.
- Also, in an evaporation fuel discharge control device, the positive pressure valve of the first communicating means and the negative pressure valve of the second communicating means are stored within the valve chamber which is formed integrally with the switch valve, and the negative pressure valve is disposed in the positive pressure valve.
- Further, if the positive pressure valve is moved, due to the high pressure used in the high flow rate of fuel supply, beyond a given distance toward the opening side of the pressure introduction passage which is opened in the valve chamber, then the negative pressure valve can be opened and the area of the passage toward the pressure introduction passage can be expanded by the passage expanding means.
- Features and advantages of the invention will be evident from the following detailed description of the preferred embodiments described in conjunction with attached drawings.
- In the accompanying drawings:
- FIG. 1 is a longitudinal section view of an embodiment of a pressure control valve according to the invention;
- FIG. 2 is a transverse section view of the pressure control valve shown in FIG. 1, taken along the line II-II shown in FIG. 1;
- FIG. 3 is a transverse section view of the pressure control valve shown in FIG. 1, taken along the line III-III shown in FIG. 1;
- FIG. 4 is a longitudinal section view of the pressure control valve shown in FIG. 1, showing a positive pressure state thereof;
- FIG. 5 is a longitudinal section view of the pressure control valve shown in FIG. 1, showing a negative pressure state thereof;
- FIG. 6 is a longitudinal section view of the pressure control valve shown in FIG. 1, showing a state thereof in which the positive pressure thereof increases suddenly;
- FIG. 7 is an explanatory view of a pipe arrangement system employed in an embodiment of an evaporation fuel discharge control device according to the invention;
- FIG. 8 is an enlarged section view of the main portions of the evaporation fuel discharge control device shown in FIG. 7;
- FIG. 9 is an enlarged section view of a valve chamber employed in the evaporation fuel discharge control device shown in FIG. 7;
- FIG. 10 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof in a car normal running operation;
- FIG. 11 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof when a cap is removed;
- FIG. 12 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof when fuel is supplied;
- FIG. 13 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof when fuel is supplied;
- FIG. 14 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof when the tank is full;
- FIG. 15 is an explanatory view of the evaporation fuel discharge control device shown in FIG. 7, showing the state of the main portions thereof when the cap is mounted;
- FIG. 16 is an explanatory view of a pipe arrangement system employed in another embodiment of an evaporation fuel discharge control device according to the invention;
- FIG. 17 is a longitudinal section view of a conventional pressure control valve; and
- FIG. 18 is an explanatory view of a pipe arrangement system employed in a conventional evaporation fuel discharge control device.
- Now, description will be given below in detail of an embodiment of a pressure control valve according to the invention with reference to the accompanying drawings.
- FIGS.1 to 3 respectively show an embodiment of a pressure control valve according to the invention.
- In use, a pressure control valve according to the present embodiment is disposed in an evapo-pipe which is used to connect together the fuel tank and canister of a car.
- In FIG. 1, a
casing 11 includes on one side thereof a firstpipe conduit portion 13, while the interior portion of the firstpipe conduit portion 13 is used as afirst port 15. - Also, the
casing 11 includes on the other side thereof a secondpipe conduit portion 17, while the interior portion of the secondpipe conduit portion 17 is used as asecond port 19. - And, the
casing 11 comprises a cylindrical-shapedportion 21 with which the firstpipe conduit portion 13 is formed integrally, and acover portion 23 with which the secondpipe conduit portion 17 is formed integrally. Thecasing 11 can be produced by connecting together the cylindrical-shapedportion 21 andcover portion 23 by ultrasonic welding or by other means. - Within the
casing 11, there is disposed apositive pressure valve 25 structured such that, when the pressure on thefirst port 15 side becomes high, it can be moved toward thesecond port 19 side to thereby allow thefirst port 15 side to communicate with thesecond port 19 side. - Also, within the
positive pressure valve 25, there is disposed anegative pressure valve 27 structured such that, when the pressure on thefirst port 15 side becomes low, it can be moved toward thefirst port 15 side to thereby allow thesecond port 19 to communicate with thefirst port 15 side. - In the present embodiment, the cylindrical-shaped
portion 21 comprises a small diameter portion 21 a and a large diameter portion 21 b, while avalve portion 25 a of thepositive pressure valve 25 is situated in the small diameter portion 21 a of the cylindrical-shapedportion 21. - And, there is formed a stepped portion21 c between the first
pipe conduit portion 13 and small diameter portion 21 a, and, in the stepped portion 21 c, there is formed a positivepressure seal surface 21 d. If thevalve portion 25 a of thepositive pressure valve 25 is contacted with the positivepressure seal surface 21 d, then the sealing operation to be executed by thepositive pressure valve 25 can be attained. - On the inner surface of the small diameter portion21 a of the cylindrical-shaped
portion 21, as shown in FIG. 2, there are provided a plurality of projection portions 21 e spaced at given angular intervals, whereby there is formed a passage portion L1 between the small diameter portion 21 a andvalve portion 25 a. - On the inner surface of the large diameter portion21 b of the cylindrical-shaped
portion 21, there is disposed a guide portion 25 b of thepositive pressure valve 25. - This guide portion25 b is formed integrally with the
valve portion 25 a. - On the inside portion of the large diameter portion21 b of the cylindrical-shaped
portion 21, as shown in FIG. 3, there are provided a plurality of projection portions 21 f spaced at given angular intervals, whereby there is formed a passage portion L2 between the large diameter portion 21 b and guide portion 25 b. - Between the
valve portion 25 a and guide portion 25 b of thepositive pressure valve 25, there is formed a stepped portion 25 c; and, between the stepped portion 25 c andcover portion 23, there is disposed a coiledspring 29 which is used to energize thepositive pressure valve 25 toward thefirst port 15 side. - The
positive pressure valve 25 is formed in a cylindrical-shaped bottomed valve which includes a passage portion. - And, a rod portion27 a of the
negative pressure valve 27 is inserted through thebottom surface portion 25 d of thepositive pressure valve 25. - The rod portion27 a is structured such that, as shown in FIG. 3, it has a cross-shaped section in a sectional view.
- On the
first port 15 side of the rod portion 27 a, there is arranged a valve portion 27 b of thenegative pressure valve 27 in such a manner that it is formed integrally with the rod portion 27 a. - The valve portion27 b of the
negative pressure valve 27 is stored within thevalve portion 25 a of thepositive pressure valve 25. - The outside diameter of the valve portion27 b of the
negative pressure valve 27 is set smaller than the inside diameter of thevalve portion 25 a of thepositive pressure valve 25 and, between thevalve portion 27 b and 25 a, there is formed a passage portion L3. - Between the
valve portion 25 a andbottom surface portion 25 d of thepositive pressure valve 25, there is formed a negativepressure seal surface 25 e. That is, if the valve portion 27 b of thenegative pressure valve 27 is contacted with the negativepressure seal surface 25 e, then a sealing operation to be executed by thenegative pressure valve 27 can be accomplished. - An energizing
portion 31, which is used to energize the rod portion 27 a of thenegative pressure valve 27 toward thesecond port 19 side, is fixed to the other end of the rod portion 27 a by thermal welding or by other means. - Between the energizing
portion 31 and thebottom surface portion 25 d of thepositive pressure valve 25, there is interposed acoiled spring 33 which is used to energize the energizingportion 31 toward thesecond port 19 side. - And, according to the present embodiment, in the
cover portion 23 of thecasing 11, there are provided projectingportions 23 a which, when thepositive pressure valve 25 has moved toward thesecond port side 19 beyond a given distance, can be contacted with the energizingportion 31 of thenegative pressure valve 27 to thereby allow the first port side to communicate with thesecond port 19 side by opening thenegative pressure valve 27. - The projecting
portions 23 a are provided on and formed integrally with the inner surface of thecover portion 23 at a given angle from the center of thecover portion 23, for example, at six positions of thecover portion 23 inner surface. - According to the above-mentioned pressure control valve, if the pressure of the
first port 15 on the fuel tank side becomes more positive than the pressure of thesecond port 19 on the canister side, as shown in FIG. 4, thepositive pressure valve 25 is moved toward thesecond port 19 side to thereby form a gap C1 between the positivepressure seal surface 21 d of the cylindrical-shapedportion 21 and thevalve portion 25 a of thepositive pressure valve 25, with the result that the fuel of thefirst port 15 side is allowed to flow through the gap C1, passage portion L1 and passage portion L2 to thesecond port 19 side. - On the other hand, if the pressure of the
first port 15 on the fuel tank side becomes more negative than the pressure of thesecond port 19 on the canister side, as shown in FIG. 5, thenegative pressure valve 27 is moved toward thefirst port 15 side to thereby form a gap C2 between the negativepressure seal surface 25 e of thepositive pressure valve 25 and the valve portion 27 b of thenegative pressure valve 27, with the result that the fuel of thesecond port 19 is allowed to flow through the gap C2 and passage portion L3 to thefirst port 15 side. - And, if the pressure within the fuel tank, that is, the pressure on the
first port 15 side increases suddenly, as shown in FIG. 6, thepositive pressure valve 25 is moved to thesecond port 19 side together with thenegative pressure valve 27, so that, similarly to the case shown in FIG. 4, the fuel is allowed to flow from thefirst port 15 side to thesecond port 19 side. - And, at the then time, since the
positive pressure valve 25 has been moved to thesecond port 19 side beyond a given distance, the projectingportions 23 a of thecover portion 23 of thecasing 11 are contacted with the energizingportion 31 of thenegative pressure valve 27 and thus thenegative pressure valve 27 is caused to move to thefirst port 15 side, thereby forming the gap C2 between the negativepressure seal surface 25 e of thepositive pressure valve 25 and the valve portion 27 b of thenegative pressure valve 27, with the result that the fuel of thefirst port 15 is allowed to flow through the passage portion L3 and gap C2 to thesecond port 19 side. - As described above, the present pressure control valve is structured such that, when the
positive pressure valve 25 has moved to thesecond port 19 side beyond a given distance, thefirst port 15 side is allowed to communicate with thesecond port 19 side by opening thenegative pressure valve 27. Thanks to this, if the pressure on thefirst port 15 side increases suddenly, then thepositive pressure valve 25 is moved to thesecond port 19 side beyond a given distance, and thenegative pressure valve 27 is thereby allowed to communicate with thesecond port 19 side, so that the fluid or fuel from thefirst port 15 is allowed to flow to thesecond port 19 through the respective flow passages of the positive andnegative pressure valves - Therefore, when the pressure on the
first port 15 side increases suddenly, a large quantity of fluid can be made to flow to thesecond port 19 side. - Also, according to the above-mentioned pressure control valve, if the pressure on the
first port 15 side increases suddenly, then thepositive pressure valve 25 is moved to thesecond port 19 side together with thenegative pressure valve 27, and, when thepositive pressure valve 25 has moved to thesecond port 19 side beyond a given distance, the projectingportions 23 a of thecasing 11 are contacted with the energizingportion 31 of thenegative pressure valve 27 to thereby allow thefirst port 15 side to communicate with thesecond port 19 side. That is, the flow passage expanding means can be structured easily and positively. - Further, according to the above-mentioned pressure control valve, since the
first port 15 is connected to the fuel tank side, while thesecond port 19 is connected to the canister side, when the pressure within the fuel tank increases suddenly, the fuel within the fuel tank can be introduced to the canister side quickly. - By the way, in the above-mentioned embodiment, description has been given of an embodiment in which the pressure control valve of the invention is disposed in the evapo-pipe of a car. However, the invention is not limited to the present embodiment but the invention can be applied widely in other various piping systems.
- Next, a description will be given below in detail of the preferred embodiments of an evaporation fuel discharge control device according to the invention with reference to the accompanying drawings.
- In particular, FIG. 7 shows an embodiment of an evaporation fuel discharge control device according to the invention.
- In FIG. 7, reference character121 designates a fuel tank.
- This fuel tank121 comprises a tank
main body 123 and a fuel supply pipe 125. - Within the tank
main body 123, there is stored volatile fuel such as gasoline, light oil or the like. - A cap125 is mounted on the entrance portion 125 a of the fuel supply pipe 125.
- In FIG. 7, reference character129 designates a canister which is used to adsorb evaporation fuel from the fuel tank 121.
- To the canister129, there is connected an
evaporation fuel passage 131 which extends from the tankmain body 123. - The
evaporation fuel passage 131 is opened on the upper surface of the tankmain body 123 through aswitch valve 133. - The
switch valve 133, as shown in FIG. 8, is a diaphragm valve which includes adiaphragm 137 within a valve main body 135 thereof. - That is, the interior portion of the valve main body135 of the
switch valve 133 is divided by thediaphragm 137 to thereby form a positive pressure chamber 139 and aback pressure chamber 141. - Within the positive pressure chamber139 of the valve main body 135, there is formed a
passage 145 which is connected through apipe 143 to the canister 129 and forms part of theevaporation fuel passage 131. - The
passage 145 is bent toward thediaphragm 137 side and includes avalve seat 145 a on thediaphragm 137 side end thereof. - On the other hand, on the
back pressure chamber 141 side, there is arranged acoiled spring 147 which energizes thediaphragm 137 toward thevalve seat 145 a of thepassage 145. - And, the
switch valve 133 is structured such that it can be opened when the pressure on the positive pressure chamber 139 side is higher by a predetermined value or more than the pressure on theback pressure chamber 141 side, whereas it is closed in other pressure conditions. - On the lower surface of the valve main body135 of the
switch valve 133, there is disposed afloat valve 149. - The
float valve 149 includes a cylindrical-shaped guide portion 151 which is formed integrally with the valve main body 135, and afloat 153 which is to be stored within the guide portion 151. - The
float 153 is energized upwardly by a coiled spring 155. - In the upper portion of the guide portion151 of the
float valve 149, there is formed aflange portion 157. - And, the
flange portion 157 of thefloat valve 149 is fixed to the upper surface of the tankmain body 123, with the guide portion 151 of thefloat valve 149 inserted through a through hole 123 a which is formed in the tankmain body 123. - The guide portion151 of the
float valve 149 is separated from the positive pressure chamber 139 of theswitch valve 133 by a partition portion 159 which is formed integrally with the valve main body 135 of theswitch valve 133. - In the partition portion159, there is formed a through hole which provides an entrance portion 161 of the
evaporation fuel passage 131. - And, when the fuel within the tank
main body 123 of the fuel tank 121 exceeds a given liquid level, the upper end of thefloat 153 is contacted with the entrance portion 161 of theevaporation fuel passage 131 to thereby close the entrance portion 161 of theevaporation fuel passage 131. - On the other hand, according to the present embodiment, at the adjoining position of the valve main body135 of the
switch valve 133, avalve chamber 163 is formed integrally with the valve main body 135. - In the
valve chamber 163, there is opened apressure introduction passage 165 which is in communication with the entrance portion 125 a of the fuel supply pipe 125. - That is, in the
valve chamber 163, there is formed apassage 167, and apipe 169 is connected to thepassage 167, whereby thepressure introduction passage 165 is formed. - In the upper portion of the
valve chamber 163, there is formed apartition portion 171. - And, through a
hole portion 171 a which is formed in thepartition portion 171, thevalve chamber 163 is allowed to be in communication with theback pressure chamber 141 side of theswitch valve 133. - According to the present embodiment, within the
valve chamber 163, there are disposed apositive pressure valve 173 forming first communicating means and anegative pressure valve 175 forming second communicating means. - That is, the
positive pressure valve 173 allows the positive pressure chamber 139 side of theswitch valve 133 to communicate with thepressure introduction passage 165 when the pressure on the positive pressure chamber 139 side is higher by a given value or more than the pressure on thepressure introduction passage 165. - Also, the
negative pressure valve 175 allows the entrance portion 161 of theevaporation fuel passage 131 to communicate with thepressure introduction passage 165 when the pressure on thepressure introduction passage 165 is higher by a given value or more than the pressure of the entrance portion 161. - In the present embodiment, as shown in FIG. 9, there is opened up a through hole177 a in a
partition portion 177 which is formed between the positive pressure chamber 139 andvalve chamber 163. - And, at a position which is outward in the diameter direction of the through hole177 a, there is arranged a cylindrical-shaped valve body 173 a of a
positive pressure valve 173. - The valve main body173 a of the
positive pressure valve 173 is energized toward thepartition portion 177 by acoiled spring 179 and, if the valve main body 173 a is contacted with thepartition portion 177, then thepositive pressure valve 173 is closed. - On the other hand, in the bottom surface173 b of the valve main body 173 a of the
positive pressure valve 173, there is formed a through hole 173 c and, in the through hole 173 c, there is disposed anegative pressure valve 175. - Within the valve main body173 a of the
positive pressure valve 173, at a position thereof which is located outward in the diameter direction of the through hole 173 c, there is disposed a cylindrical-shaped valve main body 175 a of thenegative pressure valve 175. - The valve main body175 a of the
negative pressure valve 175 is energized toward apassage 167 side by acoiled spring 181 and, if the valve main body 175 a is contacted with the bottom surface 173 b, then thenegative pressure valve 175 is closed. - And, in the present embodiment, on the opposite side of the valve main body175 a of the
negative pressure valve 175, there is arranged an energizing portion 175 b and, at positions of thevalve chamber 163 which are respectively opposed to the energizing portion 175 b of thenegative pressure valve 175, there are formed projecting portions 163 a which serve as flow passage expansion means. - The projecting portions163 a are respectively formed at an angle of, for example, 60° with the
passage 167 between them and, when thepositive pressure valve 173 moves beyond a given distance toward thepassage 167 side, the projecting portions 163 a are butted against the energizing portion 175 b of thenegative pressure valve 175. - By the way, in FIG. 7,
reference character 183 designates an evaporation fuel passage which is used to introduce the evaporation fuel within the fuel tank 121 to the canister 129 in other operations than in the fuel supply operation. - In the
evaporation fuel passage 183, there are disposed positive andnegative pressure valves evaporation fuel passage 183, there aredisposed float valves 189, 191. - In the above-mentioned evaporation fuel discharge device, in a car normal running operation, since the pressure of the interior portion of the tank
main body 123 is equal to the pressure of the interior portion of the fuel supply pipe 125, the pressure on the positive pressure chamber 139 side of theswitch valve 133 is equal to the pressure on theback pressure chamber 141 side thereof and, therefore, as shown in FIG. 10, theswitch valve 133 is closed. - And, when the cap127 is removed from the fuel supply pipe 125 for fuel supply, as shown in FIG. 11, the positive and
negative pressure valves pressure introduction passage 165 and from being discharged externally therefrom. - Next, if the internal pressure within the tank
main body 123 is increased due to the start of fuel supply, then the pressure on the positive pressure chamber 139 side of theswitch valve 133 becomes higher by a predetermined value or more than the pressure on theback pressure chamber 141 side thereof, so that, as shown in FIG. 12, theswitch valve 133 is opened and the evaporation fuel from the tankmain body 123 can be adsorbed by the canister 129 through theevaporation fuel passage 131. - And, at the then time, the pressure on the upstream side (positive pressure chamber139 side) of the
switch valve 133 becomes higher by a predetermined value or more than the pressure on thepressure introduction passage 165 side of thepositive pressure valve 173 to thereby open thepositive pressure valve 173, so that a part of the evaporation fuel within the tankmain body 123 is introduced to the entrance portion 125 a of the fuel supply pipe 125, and the evaporation fuel is returned back to the interior portion of the tankmain body 123 together with the fuel that is supplied from the fuel supply gun or the like. - This prevents an increase in the amount of the evaporation fuel which could otherwise be caused by the fresh air introduced into the tank
main body 123. - And, in the present embodiment, when the fuel is supplied in a high flow amount, the
positive pressure valve 173 is moved beyond a given distance toward thepassage 167 side due to the high pressure caused by the high flow amount of fuel supply, so that the energizing portion 175 b of thepositive pressure valve 175 is butted against the projecting portions 163 a to thereby open thenegative pressure valve 175. - As a result of this, the area of the passage is widened and thus, in the high flow amount of fuel supply, the circulating flow amount of the evaporation fuel toward the entrance portion125 a of the fuel supply pipe 125 increases to thereby reduce the amount of the air that is introduced into the tank
main body 123 from the entrance portion 125 a of the fuel supply pipe 125. - Next, if the tank
main body 123 is filled with the fuel, as shown in FIG. 14, the entrance portion 161 of theevaporation fuel passage 131 is closed by thefloat valve 149. - And, if the cap127 is mounted onto the fuel supply pipe 125 on completion of the fuel supply, then the pressure of the entrance portion 125 a of the fuel supply pipe 125 increases up to the same level of the pressure within the tank
main body 123, so that the pressures respectively on theback pressure chamber 141 side of theswitch valve 133 and on thepressure introduction passage 165 side of thepositive pressure valve 173 are caused to increase through thepressure introduction passage 165 andvalve chamber 163. - At the same time, as the pressure on the upstream side (positive pressure chamber139 side) of the
switch valve 133 is lowered because the communication with the tankmain body 123 is cut off by thefloat valve 149, theswitch valve 133 andpositive pressure valve 173 are closed. - And, as shown in FIG. 15, due to the pressure given from the
pressure introduction passage 165, thenegative pressure valve 175 is opened and the pressure on the upstream side (positive pressure chamber 139 side) of theswitch valve 133 is increased up to almost the same level as the pressure within the tankmain body 123, thereby being able to remove the sticking of thefloat valve 149 to the entrance portion 161. - In the above-structured evaporation fuel discharge control device, as described above, on completion of the fuel supply, if the cap127 is mounted onto the fuel supply pipe 125, then the pressure of the entrance portion 125 a of the fuel supply pipe 125 increases up to the same level as the pressure within the tank
main body 123. Due to the pressure given from thepressure introduction passage 165, thenegative pressure valve 175 is opened and the pressure on the upstream side (positive pressure chamber 139 side) of theswitch valve 133 is increased up to almost the same level as the pressure within the tankmain body 123, thereby being able to remove the sticking of thefloat valve 149 to the entrance portion 161. That is, the present evaporation fuel discharge control device can prevent easily and positively thefloat valve 149 from sticking to the entrance portion 161 of theevaporation fuel passage 131. - Also, in the above-mentioned evaporation fuel discharge control device, the
positive pressure valve 173 forming the first communicating means and thenegative pressure valve 175 forming the second communicating means are respectively stored within thevalve chamber 163 which is formed integrally with theswitch valve 133, while thenegative pressure valve 175 is disposed in thepositive pressure valve 173. Therefore, the first and second communicating means can be structured without using pipes which are provided separately, so that the present evaporation fuel discharge control device can be made compact. - Further, in the above-mentioned evaporation fuel discharge control device, if the
positive pressure valve 173 is moved beyond a given distance toward thepassage 167 that is opened in thevalve chamber 163 due to the high pressure in the high flow amount of fuel supply, then the energizing portion 175 b of thenegative pressure valve 175 is abutted against the projecting portions 163 a to thereby open thenegative pressure valve 175, the area of the passage can be expanded. Therefore, in the high flow amount of fuel supply, the circulating flow amount of the evaporation fuel toward the entrance portion 125 a of the fuel supply pipe 125 is increased, thereby being able to reduce the amount of the fresh air that could be otherwise taken into the tankmain body 123 from the entrance portion 125 a of the fuel supply pipe 125. - This in turn can reduce the generation of vapor and also can reduce the size of the canister129.
- Now, FIG. 16 shows another embodiment of an evaporation fuel discharge control device according to the invention and, in this embodiment, a tank
main body 123 and a canister 129 are connected to each other through anevaporation fuel passage 131. - In particular, in the second embodiment, in the entrance portion161 of the
evaporation fuel passage 131, there is disposed afloat valve 149 which is capable of closing the entrance portion 161 of theevaporation fuel passage 131 when the fuel within the tankmain body 123 exceeds a given liquid level. - In the
evaporation fuel passage 131, there is disposed aswitch valve 133 which comprises a diaphragm valve. - The
present switch valve 133 divides a positive pressure chamber 139 and aback pressure chamber 141, while theevaporation fuel passage 131 includes the positive pressure chamber 139 side of theswitch valve 133. - And, when the pressure on the positive pressure chamber139 side is higher by a predetermined value or more than the pressure on the
back pressure chamber 141 side, theevaporation fuel passage 131 is opened. - Also, there is disposed a
pressure introduction passage 165 in such a manner that it connects the entrance portion 125 a of the fuel supply pipe 125 to theback pressure chamber 141 side of theswitch valve 133. - And, in the present embodiment, there is disposed first communicating means101 which allows the upstream side of the
switch valve 133 to communicate with thepressure introduction passage 165 when the pressure on the upstream side of theswitch valve 33 is higher by a given value or more than the pressure on thepressure introduction passage 165 side thereof. - The first communicating
means 101 includes a first communicatingpassage 103 which connects the upstream side of theswitch valve 133 in theevaporation fuel passage 131 to thepressure introduction passage 165. - And, in the first communicating
passage 103, there is disposed afirst check valve 105 which can be opened when the pressure on the upstream side of theswitch valve 133 is higher by a given value or more than the pressure on thepressure introduction passage 165 side. - Also, in the present embodiment, there is disposed a second communicating means107 which allows the upstream side of the
switch valve 133 to communicate with thepressure introduction passage 165 when the pressure on thepressure introduction passage 165 side is higher by a given value or more than the pressure on the upstream side of theswitch valve 133. - The second communicating means107 includes a second communicating
passage 109 which connects the upstream side of theswitch valve 133 in theevaporation fuel passage 131 to thepressure introduction passage 165. - And, in the second communicating
passage 109, there is disposed asecond check valve 111 which can be opened when the pressure on thepressure introduction passage 165 side is higher by a given value or more than the pressure on the upstream side of theswitch valve 133. - In the evaporation fuel discharge device according to the present embodiment, in a car normal running operation, since the pressure of the interior portion of the tank
main body 123 is equal to the pressure of the interior portion of the fuel supply pipe 125, the pressure on the pressure chamber 139 side of theswitch valve 133 is equal to the pressure on theback pressure chamber 141 side thereof, so that theswitch valve 133 is closed. - And, when the cap127 is removed from the fuel supply pipe 125 for fuel supply, the
first check valve 105 of the first communicatingmeans 101 is closed, which can eliminate the possibility that the evaporation fuel can be introduced to the entrance portion 125 a of the fuel supply pipe 125 through thepressure introduction passage 165 and discharged externally therefrom. - Next, if the internal pressure within the tank
main body 123 is increased due to the start of the fuel supply, then the pressure on the positive pressure chamber 139 side of theswitch valve 133 becomes higher by a predetermined value or more than the pressure on theback pressure chamber 141 side thereof, so that theswitch valve 133 is opened and the evaporation fuel from the tankmain body 123 can be adsorbed by the canister 129 through theevaporation fuel passage 131. - And, at the then time, the pressure on the upstream side (positive pressure chamber139 side) of the
switch valve 133 becomes higher by a predetermined value or more than the pressure on thepressure introduction passage 165 side of thecheck valve 105 disposed in the first communicating means 101 to thereby open thecheck valve 105 of the first communicatingmeans 101, so that the evaporation fuel within the tankmain body 123 is introduced to the entrance portion 125 a of the fuel supply pipe 125, and the evaporation fuel is returned back to the interior portion of the tankmain body 123 together with the fuel that is supplied from afuel supply gun 113 or the like. - Thanks to the above, an increase in the amount of the evaporation fuel, which could be otherwise caused by introduction of the fresh air into the tank
main body 123, can be prevented. - Next, if the tank
main body 123 is filled up with the fuel, then the entrance portion 161 of theevaporation fuel passage 131 is closed by thefloat valve 149 and, if the pressure on the upstream side of theswitch valve 133 is lowered, then theswitch valve 33 andcheck valve 105 are closed respectively. - After then, if the cap127 is mounted onto the fuel supply pipe 125 on completion of the fuel supply, then the pressure of the entrance portion 125 a of the fuel supply pipe 125 increases up to the same level as the pressure within the tank
main body 123 to thereby open thesecond check valve 111 of the second communicating means 107 through thepressure introduction passage 165, which increases the pressure on the upstream side of theswitch valve 133 up to almost the same level to the pressure within the tankmain body 123, thereby being able to remove the sticking of thefloat valve 149 to the entrance portion 161. - That is, according to the second embodiment as well, it is possible to prevent the
float valve 149 from sticking to the entrance portion 161 of theevaporation fuel passage 131. - As has been described heretofore, according to a pressure control valve according to the present invention, since there is formed the flow passage expanding means which, when the positive pressure valve has moved to the second port side beyond a given distance, allows the first port side to communicate with the second port side, if the pressure on the first port side increases suddenly, then the positive pressure valve is moved to the second port side beyond a given distance to thereby allow the firs port side to communicate with the second port side, so that the fluid or fuel from the first port side is allowed to flow to the second port through the respective flow passages of the positive and negative pressure valves.
- Therefore, when the pressure on the first port side increases suddenly, a large quantity of fluid can be made to flow to the second port side.
- Also, if the pressure on the first port side increases suddenly, then the positive pressure valve is moved to the second port side together with the negative pressure valve, and, when the positive pressure valve has moved to the second port side beyond a given distance, the projecting portion of the casing is contacted with the energizing portion of the negative pressure valve to thereby allow the first port side to communicate with the second port side. Therefore, according to the present pressure control valve, the flow passage expanding means can be structured easily and positively.
- Further, in the case that the first port is connected to the fuel tank side, while the second port is connected to the canister side, when the pressure within the fuel tank increases suddenly, the evaporation fuel within the fuel tank can be introduced to the canister side quickly.
- As has been described heretofore, in an evaporation fuel discharge control device according to the present invention, on completion of oil supply, if the cap is mounted on the fuel supply pipe, then the pressure of the entrance portion of the fuel supply pipe increases up to the same level as the pressure within the tank main body, and thus the second communicating means is opened through the pressure introduction passage to thereby increase the pressure on the upstream side of the switch valve up to almost the same level as the same level as the pressure within the tank main body, thereby being able to remove the sticking of the float valve to the entrance portion of an evaporation fuel passage. That is, the present evaporation fuel discharge control device is able to prevent easily and positively the float valve from sticking to the entrance portion of the evaporation fuel passage.
- Also, in the case that the positive pressure valve of the first communicating means and the negative pressure valve of the second communicating means are stored within the valve chamber which is formed integrally with the switch valve and the negative pressure valve is disposed in the positive pressure valve, the first and second communicating means can be structured without using a separately provided pipe, which makes it possible to make compact the present evaporation fuel discharge control device.
- Further, if the positive pressure valve is moved, due to the high pressure used in the high flow rate of fuel supply, beyond a given distance toward the opening side of the pressure introduction passage which is opened in the valve chamber, then the negative pressure valve can be opened and the area of the passage toward the pressure introduction passage can be expanded by the passage expanding means and, therefore, in the high flow rate of fuel supply, the flow rate of the circulating evaporation fuel toward the entrance portion side of the fuel supply pipe is increased to thereby be able to reduce the amount of the fresh air taken into the fuel from the entrance portion of the fuel supply pipe.
- And, thanks to the above, not only generation of the vapor can be reduced but also the canister can be made compact.
- Although the invention has been described in its preferred formed with a certain degree of particularity, it is understood that the present disclosure of the preferred form can be changed in the details of construction and in the combination and arrangement of parts without departing from the spirit and the scope of the invention as hereinafter claimed.
Claims (7)
1. A pressure control valve comprising:
a casing having a first port formed on a first side of said casing, a second port formed on a second side;
a positive pressure valve being disposed in said casing, said positive pressure valve moving to a side of said second port for a side of said first side to thereby communicating with the side of said second port when a pressure on the side of said first port becomes higher than the pressure on the side of said second port;
a negative pressure valve being disposed in said casing, said negative pressure valve moving to the side of said first port for the side of said first port to thereby communicating with the side of said second port when the pressure on the side of said first port becomes lower than the pressure on the side of said second port; and
flow passage expanding means which, when said positive pressure valve has moved to the side of said second port beyond a given distance, allows the side of said first port to communicate with the side of said second port by moving said negative pressure valve to the side of said first port.
2. A pressure control valve according to claim 1 ,
wherein said positive pressure valve is formed as a cylindrical-shaped bottomed valve having a passage portion,
wherein said negative pressure valve has a rod portion extending through a bottom surface portion of said positive pressure valve, a valve portion stored within said positive pressure valve and connected to a first end of said rod portion on the side of said first port, and an energizing portion connected to a second end of said rod portion for energizing said rod portion to the side of said second port, and
wherein, on the side of said second port of said casing, a projecting portion is formed which, when said positive pressure valve has moved to the side of said second port beyond a given distance, can be contacted with said energizing portion of said negative pressure valve to thereby allow the side of said first port to communicate with the side of said second port by opening said negative pressure valve.
3. A pressure control valve according to claim 1 , wherein said first port is connected to a fuel tank, whereas said second port is connected to a canister.
4. A pressure control valve according to claim 2 , wherein said first port is connected to a fuel tank, whereas said second port is connected to a canister.
5. An evaporation fuel discharge control device, comprising:
a canister for adsorbing evaporation fuel from a fuel tank having a tank main body with a fuel supply pipe;
an evaporation fuel passage for connecting said tank main body and said canister;
a float valve disposed within the tank main body for closing an entrance portion of said evaporation fuel passage when fuel within the tank main body exceeds a given liquid level;
a switch valve assembly including a positive pressure chamber and a back pressure chamber, said evaporation fuel passage being disposed on a side of said positive pressure chamber, and said switch valve being structured such that it can be opened when a pressure on the side of said positive pressure chamber is higher by a predetermined value or more than a pressure on a side of said back pressure chamber;
a pressure introduction passage for connecting an entrance portion of said fuel supply pipe to said back pressure chamber of said switch valve;
first communicating means for allowing an upstream side of said switch valve to communicate with said pressure introduction passage when a pressure on the upstream side of said switch valve is higher by a given value or more than a pressure on a side of said pressure introduction passage; and
second communicating means for allowing the upstream side of said switch valve to communicate with said pressure introduction passage when the pressure on the side of said pressure introduction passage is higher by a given value or more than the pressure on the upstream side of said switch valve.
6. An evaporation fuel discharge control device according to claim 5 , wherein said first and second communicating means include a positive pressure valve and a negative pressure valve to be stored within a valve chamber which is formed integrally with said switch valve, and said negative pressure valve is disposed in said positive pressure valve.
7. An evaporation fuel discharge control device according to claim 6 , further including passage expansion means for opening said negative pressure valve when said positive pressure valve is moved beyond a given distance toward an opening of said pressure introduction passage, said opening of said pressure introduction passage being opened in said valve chamber.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/769,267 US6353955B2 (en) | 1998-04-16 | 2001-01-26 | Pressure control valve and evaporation fuel discharge control device |
Applications Claiming Priority (8)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JPH.10-106055 | 1998-04-16 | ||
JP10-106055 | 1998-04-16 | ||
JP10106055A JPH11304028A (en) | 1998-04-16 | 1998-04-16 | Pressure control valve |
JP11059674A JP2000257514A (en) | 1999-03-08 | 1999-03-08 | Evaporated fuel discharge suppressing device |
JPH.11-59674 | 1999-03-08 | ||
US09/292,856 US6196258B1 (en) | 1998-04-16 | 1999-04-16 | Pressure control valve and evaporation fuel discharge control device |
JP11-59674 | 1999-08-03 | ||
US09/769,267 US6353955B2 (en) | 1998-04-16 | 2001-01-26 | Pressure control valve and evaporation fuel discharge control device |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/292,856 Division US6196258B1 (en) | 1998-04-16 | 1999-04-16 | Pressure control valve and evaporation fuel discharge control device |
Publications (2)
Publication Number | Publication Date |
---|---|
US20020017282A1 true US20020017282A1 (en) | 2002-02-14 |
US6353955B2 US6353955B2 (en) | 2002-03-12 |
Family
ID=26400746
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/292,856 Expired - Fee Related US6196258B1 (en) | 1998-04-16 | 1999-04-16 | Pressure control valve and evaporation fuel discharge control device |
US09/769,267 Expired - Fee Related US6353955B2 (en) | 1998-04-16 | 2001-01-26 | Pressure control valve and evaporation fuel discharge control device |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/292,856 Expired - Fee Related US6196258B1 (en) | 1998-04-16 | 1999-04-16 | Pressure control valve and evaporation fuel discharge control device |
Country Status (1)
Country | Link |
---|---|
US (2) | US6196258B1 (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004026608A1 (en) * | 2002-08-21 | 2004-04-01 | Daimlerchrysler Ag | Ventilation device for fuel tanks |
GB2405684A (en) * | 2003-09-04 | 2005-03-09 | Nifco Inc | Pressure control valve for fuel tank |
US20090301583A1 (en) * | 2008-06-05 | 2009-12-10 | Mills Vaughn K | Small engine fuel system |
US20110126923A1 (en) * | 2008-07-29 | 2011-06-02 | Opw Fluid Transfer Group B.V. | Valve Assembly |
US20130213364A1 (en) * | 2010-10-28 | 2013-08-22 | Kautex Textron Gmbh & Co. Kg | Fuel tank for motor vehicles |
CN111373136A (en) * | 2017-11-27 | 2020-07-03 | 法国大陆汽车公司 | Detection method for detecting gas flow defects in a ventilation line of a purging device |
Families Citing this family (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IL137529A0 (en) * | 2000-07-26 | 2001-07-24 | Raviv Prec Injection Molding | Vapor recovery control valve |
US6843271B2 (en) * | 2000-08-08 | 2005-01-18 | Siemens Vdo Automotive, Inc. | Fuel tank pressure control valve including an integrated sensor |
JP2003240143A (en) * | 2002-02-14 | 2003-08-27 | Nifco Inc | Two-way valve |
FR2869382B1 (en) * | 2004-04-23 | 2007-12-21 | Eaton Sa Monegasque | VALVE FOR MONITORING THE INTERNAL GAS PRESSURE OF A RESERVOIR |
FR2869383B1 (en) | 2004-04-23 | 2008-03-21 | Eaton Sa Monegasque | VALVE FOR MONITORING THE INTERNAL GAS PRESSURE OF A RESERVOIR |
US7287542B2 (en) * | 2005-04-08 | 2007-10-30 | Eaton Corporation | Shutoff valve for mechanically sealed ORVR system |
DE102005020853B3 (en) * | 2005-05-02 | 2006-08-10 | Fte Automotive Gmbh | Valve device for decoupling vibrations has second through passage for hydraulic fluid between first valve body and housing |
US7527044B2 (en) * | 2005-10-28 | 2009-05-05 | Stant Manufacturing Inc. | Small engine carbon canister with check valve |
DE102007025048B4 (en) * | 2007-05-29 | 2012-08-30 | Eagle Actuator Components Gmbh & Co. Kg | Valve for limiting the tank pressure of a motor vehicle |
US20090235994A1 (en) * | 2008-03-19 | 2009-09-24 | Denso International America, Inc. | Coaxial pressure retention and relief mechanism |
JP5145431B2 (en) * | 2008-12-02 | 2013-02-20 | 株式会社パイオラックス | Check valve |
WO2013031273A1 (en) * | 2011-09-01 | 2013-03-07 | 株式会社パイオラックス | Check valve |
EP3099520A1 (en) * | 2014-01-30 | 2016-12-07 | Raval A.C.S. LTD | Pressure relief valve |
JP6338996B2 (en) * | 2014-10-10 | 2018-06-06 | 株式会社パイオラックス | Check valve |
RU2702297C2 (en) | 2014-11-05 | 2019-10-07 | РАВАЛ Эй.Си.Эс. ЛТД. | Pressure relief valve (embodiments) and valve assembly containing said valve |
JP6578585B2 (en) * | 2015-11-12 | 2019-09-25 | 株式会社パイオラックス | Valve device |
JP6670594B2 (en) * | 2015-11-18 | 2020-03-25 | 株式会社パイオラックス | Check valve |
DE102020115850A1 (en) | 2020-06-16 | 2021-12-16 | Pierburg Gmbh | Flow limiting element for a fuel vapor switching and ventilation valve of an internal combustion engine |
Family Cites Families (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1153770A (en) * | 1914-06-02 | 1915-09-14 | Eugene A Daymon | Automatic cylinder-cock. |
US1620720A (en) * | 1925-07-27 | 1927-03-15 | Gustin Bacon Mfg Co | Combination vacuum and pressure relief valve |
US2191636A (en) * | 1938-05-05 | 1940-02-27 | Gen Motors Corp | Radiator overflow valve |
FR2221962A5 (en) * | 1973-03-14 | 1974-10-11 | Journee Paul | |
JPS5069421A (en) * | 1973-10-24 | 1975-06-10 | ||
JPS6483976A (en) | 1987-09-25 | 1989-03-29 | Fujitsu Ltd | Magnetic fluid seal device |
US5099880A (en) * | 1989-03-24 | 1992-03-31 | Stant Inc. | Fuel tank venting control valve assembly |
US5603349A (en) * | 1992-01-17 | 1997-02-18 | Stant Manufacturing Inc. | Tank venting system |
JPH07290981A (en) * | 1994-04-26 | 1995-11-07 | Toyoda Gosei Co Ltd | Fuel vapor collection control valve gear |
JP3348568B2 (en) * | 1994-12-13 | 2002-11-20 | トヨタ自動車株式会社 | Fuel evaporative emission control system |
US5584278A (en) * | 1994-12-15 | 1996-12-17 | Nissan Motor Co., Ltd. | System for controlling fuel vapor flow discharged from a fuel tank to a canister |
JP2920226B2 (en) | 1994-12-28 | 1999-07-19 | 本田技研工業株式会社 | Evaporative fuel emission control device |
JP3391202B2 (en) * | 1996-12-27 | 2003-03-31 | スズキ株式会社 | Evaporative fuel control system for internal combustion engine |
JP3902694B2 (en) * | 1997-08-29 | 2007-04-11 | 富士重工業株式会社 | Fuel vapor emission prevention device |
US6003499A (en) * | 1998-01-07 | 1999-12-21 | Stant Manufacturing Inc. | Tank vent control apparatus |
-
1999
- 1999-04-16 US US09/292,856 patent/US6196258B1/en not_active Expired - Fee Related
-
2001
- 2001-01-26 US US09/769,267 patent/US6353955B2/en not_active Expired - Fee Related
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004026608A1 (en) * | 2002-08-21 | 2004-04-01 | Daimlerchrysler Ag | Ventilation device for fuel tanks |
US20050155670A1 (en) * | 2002-08-21 | 2005-07-21 | Dorothee Aschoff | Venting device for fuel tanks |
US7152639B2 (en) | 2002-08-21 | 2006-12-26 | Daimlerchrysler Ag | Venting device for fuel tanks |
GB2405684A (en) * | 2003-09-04 | 2005-03-09 | Nifco Inc | Pressure control valve for fuel tank |
US20050051216A1 (en) * | 2003-09-04 | 2005-03-10 | Hiroji Sato | Pressure opening and closing valve |
GB2405684B (en) * | 2003-09-04 | 2007-05-02 | Nifco Inc | Pressure opening and closing valve |
US20090301583A1 (en) * | 2008-06-05 | 2009-12-10 | Mills Vaughn K | Small engine fuel system |
WO2009147516A1 (en) * | 2008-06-05 | 2009-12-10 | Eaton Corporation | Small engine fuel system |
US20110126923A1 (en) * | 2008-07-29 | 2011-06-02 | Opw Fluid Transfer Group B.V. | Valve Assembly |
US20130213364A1 (en) * | 2010-10-28 | 2013-08-22 | Kautex Textron Gmbh & Co. Kg | Fuel tank for motor vehicles |
CN111373136A (en) * | 2017-11-27 | 2020-07-03 | 法国大陆汽车公司 | Detection method for detecting gas flow defects in a ventilation line of a purging device |
Also Published As
Publication number | Publication date |
---|---|
US6196258B1 (en) | 2001-03-06 |
US6353955B2 (en) | 2002-03-12 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6353955B2 (en) | Pressure control valve and evaporation fuel discharge control device | |
US5850819A (en) | Fuel evaporative emission treatment system | |
US6810900B2 (en) | Composite type air vent valve of fuel tank and air vent mechanism | |
US7806135B2 (en) | Variable flow valve | |
JP2765824B2 (en) | Fuel tank gas exhaust system | |
KR101189341B1 (en) | Internal tank gas pressure control valve | |
JP2006097674A (en) | Fuel cut-off valve | |
KR20000071574A (en) | Refrigerant system components with cartridge type thermal expansion valve and method of making same | |
EP1505291B1 (en) | Fuel supply control system for engine | |
JP2004068709A (en) | Fuel shut-off valve device | |
JP2827899B2 (en) | Check valve | |
JP4196171B2 (en) | Tank gas pressure control valve | |
AU2004203116B2 (en) | Fuel supply control system for engine | |
US5722468A (en) | Evaporative-fuel emission preventing apparatus | |
JP2002285929A (en) | Over-refueling preventive valve | |
US5447175A (en) | Fuel delivery device of fuel tank | |
CN100404300C (en) | Connecting structure for parts in fuel tank made of resin | |
US6886543B2 (en) | Fuel supply control system for engine | |
US4194589A (en) | Valve | |
US6726185B1 (en) | Rollover valve for carburetor float bowls | |
US4724867A (en) | Vacuum check valve | |
JPH1162725A (en) | Cutoff valve | |
JPH04365627A (en) | Float valve of fuel tank | |
JP4030480B2 (en) | Engine fuel supply control device | |
JPH0986196A (en) | Pressure control valve and fuel steam pressure controller |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
FPAY | Fee payment |
Year of fee payment: 4 |
|
REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20100312 |