JP6919459B2 - Flow control device - Google Patents

Description

The disclosure herein relates to a flow rate regulator that controls the flow rate of the evaporated fuel.

Patent Document 1 discloses a purge valve which is a solenoid valve capable of adjusting the flow rate of evaporated fuel flowing from the canister side to the intake pipe side of the engine. In recent years, the negative pressure of an engine has tended to decrease due to the reduction of fuel consumption of the engine. Along with this, the flow rate of the evaporated fuel that can be adjusted by the purge valve has increased.

Japanese Unexamined Patent Publication No. 2013-24399

The range of pressure fluctuation between the purge valve and the canister increases as the maximum flow rate that the purge valve can adjust increases. Therefore, there is a problem that the larger the passage cross-sectional area of the purge valve is, the larger the amplitude of the pipes and canisters connected to the purge valve, and the larger the vibration, sound, and the like transmitted to the vehicle interior through these.

An object of the disclosure in this specification is to provide a flow rate adjusting device capable of reducing noise and the like due to pressure fluctuations.

The plurality of aspects disclosed herein employ different technical means to achieve their respective objectives. Further, the scope of claims and the reference numerals in parentheses described in this section are examples showing the correspondence with the specific means described in the embodiment described later as one embodiment, and limit the technical scope. is not it.

One of the disclosed flow control devices is separated from the housing (150) having the fuel passage (153) through which the evaporated fuel flowing out from the canister (13) due to the intake pressure of the engine (2) flows, and the valve seat (155). A valve body (152) that opens and closes the fuel passage so as to switch between an open state that allows the flow of the vaporized fuel and a closed state that contacts the valve seat and blocks the flow of the vaporized fuel, and an open state and a closed state. In the electromagnetic solenoid unit (151) that generates a driving force that drives the movable core (1511) that is displaced together with the valve body in the axial direction, and the inflow side passage (154a) that is located on the canister side of the valve body. It includes an actuator (16) that drives a flow rate adjusting unit (161) that can adjust the cross-sectional area of the flow path, and a control device (50) that controls the operation of the actuator. The control device controls the actuator so as to narrow the cross-sectional area of the flow path in the inflow side passage when a predetermined vehicle condition condition in which noise due to pressure fluctuation can be assumed is satisfied.

According to this flow rate adjusting device, when a predetermined vehicle condition condition in which noise due to pressure fluctuation can be assumed is satisfied, the pressure fluctuation in the passage through which the evaporated fuel flows in order to narrow the flow path cross-sectional area in the inflow side passage. Can be suppressed. By narrowing the inflow side passage located on the canister side of the valve body, it is possible to suppress the fluctuation range of the pressure propagating from the fuel flow path in the housing to the canister side through the inflow side passage. From the above, a flow rate adjusting device capable of reducing noise and the like due to pressure fluctuation can be obtained.

One of the disclosed flow control devices is separated from the housing (150) having the fuel passage (153) through which the evaporative fuel flowing out from the canister (13) due to the intake pressure of the engine (2) flows, and the valve seat (155). The valve body (152) that opens and closes the fuel passage so as to switch between the open state that allows the flow of the solenoid fuel and the closed state that contacts the valve seat and blocks the flow of the solenoid fuel, and the open state and the closed state. In the electromagnetic solenoid unit (151) that generates a driving force that drives the movable core (1511) that is displaced together with the valve body in the axial direction, and the inflow side passage (154a) that is located on the canister side of the valve body. The actuator (16) that drives the flow rate adjusting unit (161) that can adjust the cross-sectional area of the flow path, the control device (50) that controls the duty ratio of the voltage applied to the electromagnetic solenoid unit, and the electromagnetic solenoid unit and the actuator. A low-pass filter (17) provided in the middle of the energization path for communication is provided, and the low-pass filter outputs to the actuator when the duty ratio value of the voltage applied to the electromagnetic solenoid unit exceeds a predetermined duty ratio value. By lowering the voltage applied to the electromagnetic solenoid section with respect to the voltage applied to the electromagnetic solenoid section, the output voltage to the actuator increases more than before, and the flow rate adjusting section narrows the flow path cross-sectional area in the inflow side passage.

According to this flow rate adjusting device, when the duty ratio value of the voltage applied to the electromagnetic solenoid section exceeds a predetermined duty ratio value, the output voltage of the actuator is lowered by the low-pass filter and the output voltage to the actuator is higher than before. Will also increase. As a result, the actuator operates to reduce the cross-sectional area of the flow path in the inflow side passage. In this way, since the inflow side passage located on the canister side of the valve body is narrowed, the fluctuation range of the pressure propagating from the fuel flow path in the housing to the canister side through the inflow side passage can be suppressed. From the above, it is possible to obtain a flow rate adjusting device capable of reducing noise and the like due to pressure fluctuation without having a function of determining the vehicle state condition in the control device and performing processing according to the determination result.

It is a figure which showed the evaporative fuel processing apparatus provided with the flow rate adjusting apparatus of 1st Embodiment. It is a schematic diagram for demonstrating the structure of the flow rate adjusting apparatus. It is a schematic diagram for demonstrating the state that the inflow side passage is not narrowed. It is a schematic diagram for demonstrating the state which narrowed the inflow side passage. It is a flowchart which showed the control process which concerns on the flow rate adjustment apparatus of 1st Embodiment. It is a flowchart which showed the control process which concerns on the flow rate adjustment apparatus of 2nd Embodiment. It is a block diagram for demonstrating the flow rate adjustment apparatus of 3rd Embodiment. It is a chart figure which showed the control which concerns on the flow rate adjusting apparatus of 3rd Embodiment.

Hereinafter, a plurality of modes for carrying out the present disclosure will be described with reference to the drawings. In each form, the same reference numerals may be attached to the parts corresponding to the matters described in the preceding forms, and duplicate explanations may be omitted. When only a part of the configuration is described in each form, the other forms described above can be applied to the other parts of the configuration. Not only the combinations of the parts that clearly indicate that they can be combined in each embodiment, but also the parts of the embodiments that are not explicitly combined unless there is a problem in the combination. It is also possible.

(First Embodiment)
The first embodiment will be described with reference to FIGS. 1 to 5. The flow rate adjusting device is used in the evaporative fuel processing device 1 which is an evaporative fuel purging system mounted on a vehicle. As shown in FIG. 1, the evaporative fuel processing device 1 supplies HC gas or the like in the fuel adsorbed on the canister 13 to the intake passage of the engine 2, and the evaporative fuel from the fuel tank 10 is released to the atmosphere. To prevent. The evaporative fuel processing device 1 includes an intake system of the engine 2 that constitutes an intake passage of the engine 2 that is an internal combustion engine, and an evaporative fuel purge system that supplies the evaporative fuel to the intake system of the engine 2.

The evaporated fuel introduced into the intake passage by the intake pressure of the engine 2 is mixed with the combustion fuel supplied to the engine 2 from the injector or the like and burned in the combustion chamber of the engine 2. The engine 2 mixes and burns at least the evaporated fuel desorbed from the canister 13 and the combustion fuel. The intake system of the engine 2 is configured such that an intake pipe 21 constituting an intake passage is connected to an intake manifold 20 and a throttle valve 25, an air filter 24 and the like are provided in the middle of the intake pipe 21.

In the evaporated fuel purge system, the fuel tank 10 and the canister 13 are connected by a pipe 11 forming a vapor passage, and the canister 13 and the intake pipe 21 are connected via a pipe 14 forming a purge passage and a purge valve 15. A purge pump may be provided in the middle of the purge passage. The air filter 24 is provided in the upstream portion of the intake pipe 21 and captures dust, dust, etc. in the intake pipe. The throttle valve 25 is an intake air amount adjusting valve that adjusts the opening degree of the inlet portion of the intake manifold 20 to adjust the intake air amount flowing into the intake manifold 20. The intake air passes through the intake air passage, flows into the intake manifold 20, is mixed with the combustion fuel injected from the injector or the like so as to have a predetermined air-fuel ratio, and is burned in the combustion chamber.

The fuel tank 10 is a container for storing fuel such as gasoline. The fuel tank 10 is connected to the inflow portion of the canister 13 by a pipe 11 forming a vapor passage. The canister 13 is a container in which an adsorbent such as activated carbon is sealed, and the evaporated fuel generated in the fuel tank 10 is taken in through the vapor passage and temporarily adsorbed on the adsorbent.

A valve module 12 is integrally provided on the canister 13. The valve module 12 includes a canister closed valve that opens and closes a suction unit for sucking in fresh air from the outside, and an internal pump that can release gas to the atmosphere and suck in the atmosphere. It is built-in. When the canister 13 is provided with the canister close valve, atmospheric pressure can be applied to the inside of the canister 13. The canister 13 can easily desorb, that is, purge the evaporated fuel adsorbed on the adsorbent by the sucked fresh air.

The purge valve 15 is a switchgear having a purge passage, that is, a valve body 152 for opening and closing the fuel passage 153 provided inside the housing 150, and permits and blocks the supply of the evaporated fuel from the canister 13 to the engine 2. can. The purge valve 15 is a valve device that keeps the fuel passage 153 closed during normal times when no voltage is supplied. The purge valve 15 is a normally closed type valve device controlled to be in a closed state in which the fuel passage 153 is closed when no voltage is applied and in an open state in which the fuel passage 153 is opened when a voltage is applied. By switching between the open state and the closed state in this way, the purge valve 15 can adjust the purge amount of the evaporated fuel in the evaporated fuel processing apparatus 1.

In recent years, the negative pressure of the engine has tended to decrease due to the fuel efficiency of the engine, and the purge valve is required to have a performance capable of adjusting a large flow rate. On the other hand, it is known that the fluctuation range of the pressure when the valve body of the purge valve 15 moves from the valve open state to the valve closed state increases as the maximum adjustable flow rate of the purge valve 15 increases. Therefore, the larger the adjustable flow rate value of the purge valve 15, the larger the fluctuation range of the pressure between the purge valve 15 and the canister 13, and this phenomenon causes noise in the vehicle. Since the piping connecting the purge valve 15 and the canister 13 is provided under the floor in the vehicle interior, for example, noise due to vibration of the piping is easily transmitted to the vehicle interior. Therefore, the evaporative fuel processing device 1 of this embodiment has a function of suppressing the pressure fluctuation range.

As shown in FIG. 2, the purge valve 15 includes a valve seat 155, a valve body 152, an electromagnetic solenoid unit 151, and the like. The electromagnetic solenoid unit 151 includes a yoke, a bobbin, a coil 1510, a fixed core, a movable core 1511, a connector for power supply, and the like. The yoke, fixed core, movable core 1511 and the like are made of a magnetic material. The electromagnetic solenoid unit 151 is configured so that the current energizing the coil 1510 can be controlled by electrically connecting the terminal terminal to the control device 50 or the like that controls the supply voltage with a connector.

The electromagnetic solenoid unit 151 is used to switch between an open state in which the valve body 152 is separated from the valve seat 155 to allow fluid flow and a closed state in which the valve body 152 contacts the valve seat 155 to prevent fluid flow. A driving force is generated to drive the movable core 1511 that is integrally displaced with the movable core 1511 in the axial direction. When the coil 1510 of the electromagnetic solenoid unit 151 is energized from the closed state, magnetic flux is generated in the magnetic circuit formed by the yoke, the movable core 1511, the fixed core, and the like. Due to the magnetic force associated with this magnetic flux, the movable core 1511 is attracted axially toward the fixed core side and moves toward the fixed core side against the urging force of the spring, and the valve body 152 is separated from the valve seat 155. Then, the fuel passage 153 is opened and opened.

For example, the control device 50 controls the ratio of the on-time to the time of one cycle formed by the on-time and the off-time of energization, that is, the duty ratio, and energizes the coil 1510. The purge valve 15 is also referred to as a duty control valve. The purge valve 15 can continuously control the valve opening amount by changing the duty ratio controlled by the duty signal. By this energization control, the flow rate (purge amount) of the evaporated fuel flowing through the fuel passage 153 can be adjusted.

The housing 150 of the purge valve 15 is provided with an input port 154 that receives a fluid supply from the canister 13 side and an output port 156 that allows the fluid to flow out to the engine 2 side. The housing 150 houses the electromagnetic solenoid unit 151, the valve body 152, and the like. The inflow side passage 154a provided inside the input port 154 communicates with the canister 13 via a pipe 14 connected to the canister 13. The inflow side passage 154a is a passage located on the canister 13 side of the fuel passage 153 and the valve body 152. The inflow side passage 154a is configured so that the flow rate of the evaporated fuel flowing in from the canister 13 side can be adjusted by the flow rate adjusting valve 161. The flow rate adjusting valve 161 is a flow rate adjusting unit that can adjust the opening degree of the inflow side passage 154a, that is, the cross-sectional area of the flow path in the inflow side passage 154a. The flow rate adjusting valve 161 is driven by the actuator 16 to adjust the opening degree of the inflow side passage 154a.

Similar to the electromagnetic solenoid portion 151 of the purge valve 15, the actuator 16 moves the movable core 162 integrated with the flow rate adjusting valve 161 in the axial direction by the electromagnetic force generated by the supply voltage. The actuator 16 maintains a normal state (fully open state) in which the fuel passage 153 is not narrowed in a non-energized state in which no voltage is supplied. When the coil 163 is energized by the control device 50, the actuator 16 is brought into a throttled state in which the generated electromagnetic force overcomes the elastic force of the spring and the flow rate adjusting valve 161 narrows the inflow side passage 154a.

The control device 50 has at least one arithmetic processing unit (CPU) and at least one memory device as a storage medium for storing programs and data. The control device 50 is provided by a microcomputer having a storage medium that can be read by a computer, for example. A storage medium is a non-transitional substantive storage medium that stores a computer-readable program non-temporarily. The storage medium may be provided by a semiconductor memory, a magnetic disk, or the like. The control device 50 may be provided by a single computer, or a set of computer resources linked by a data communication device. By being executed by the control device 50, the program causes the control device 50 to function as the device described herein, and the control device 50 to perform the methods described herein.

The means and / or functions provided by the control device 50 can be provided by software recorded in a substantive memory device and a computer, software only, hardware only, or a combination thereof that executes the software. For example, if the control device 50 is provided by an electronic circuit that is hardware, it can be provided by a digital circuit or an analog circuit that includes a large number of logic circuits.

The actuator 16 can switch the inflow side passage 154a between a fully open state and a throttled state. The fully open state is when the actuator 16 is in a non-energized state, and as shown in FIG. 3, the flow rate adjusting valve 161 is located closest to the actuator 16 and is above the inflow side passage 154a. In the fully open state, the pressure fluctuation propagating from the valve body 152 to the inflow side passage 154a is transmitted to the canister 13 side passage in the inflow side passage 154a without reducing the amplitude, as shown by the broken line in FIG.

The throttle state is a state in which a voltage is supplied to the actuator 16, and as shown in FIG. 4, the flow rate adjusting valve 161 is located at the position farthest from the actuator 16, and the flow path cross-sectional area in the inflow side passage 154a is throttled. It is in a state of being. In the throttled state, the pressure fluctuation propagating from the valve body 152 to the inflow side passage 154a has a small amplitude when passing through the narrowed inflow side passage 154a as shown by the broken line in FIG. 4, and the passage on the canister 13 side. Will be transmitted to. Compared to the fully open state, the pressure fluctuation transmitted to the passage on the canister 13 side is suppressed in the throttle state, so when noise can be expected, the pulsation in the passage on the canister 13 side is reduced by controlling the throttle state. Noise can be prevented in advance.

The operation of the flow rate adjusting device will be described with reference to the flowchart of FIG. The control device 50 executes the process according to the flowchart of FIG. This flowchart operates regardless of whether the engine 2 is running, stopped, or parked.

When this flowchart is started, the control device 50 determines whether or not the vehicle state condition predetermined in step S100 is satisfied. The vehicle condition is a preset condition that can be assumed to generate noise due to pressure fluctuation in the passage through which the evaporated fuel flows. The vehicle state condition can be set to a condition in which the vehicle is stopped and the engine 2 is in operation. That is, if the current vehicle state corresponds to a signal waiting, a stopped vehicle, an idling state before departure, or the like, the control device 50 determines that the vehicle state condition is satisfied in step S100. .. If it is determined in step S100 that the vehicle state condition is not satisfied, the process of step S100 is repeatedly executed.

When the vehicle state condition is satisfied when the vehicle is stopped and the engine 2 is operating, the road noise or the like due to running is not generated, so that the noise due to the pressure fluctuation is running. Compared to the above, it is more easily transmitted to the occupants in the passenger compartment and may cause noise. In order to suppress this noise, when the vehicle state condition is satisfied in step S100, the control device 50 executes a process of controlling the actuator 16 so that the flow rate adjusting valve 161 is operated in the throttle state in step S110. The control device 50 then returns to step S100 and continuously executes the process of step S100.

Further, the control device 50 may execute a process of determining that the vehicle state condition is satisfied when the current vehicle speed is lower than the predetermined speed in step S100. The control device 50 acquires the current vehicle speed based on the vehicle speed information detected by the vehicle speed sensor 61. The vehicle speed sensor 61 outputs vehicle speed information to the vehicle ECU 60 that controls the running of the vehicle and the cooling system necessary for running the vehicle, and the vehicle speed information is output from the vehicle ECU 60 to the control ECU. The predetermined speed is preferably set based on experimental results or empirical rules, and is set to a vehicle speed that makes it difficult for the occupants in the vehicle interior to recognize the sound caused by the pressure fluctuation because the running noise drowns out the sound. By setting the vehicle condition to a condition where the current vehicle speed is lower than the predetermined speed, when the vehicle speed is low and there is not much running noise, the noise caused by the pressure fluctuation becomes noise to the occupants in the vehicle interior. It can be suppressed.

Further, the control device 50 may execute a process of determining in step S100 that the vehicle state condition is satisfied when the current rotation speed of the engine 2 is lower than the predetermined rotation speed. When this determination process is adopted, the predetermined rotation speed is preferably set based on experimental results or empirical rules, and the rotation speed is set so that the sound accompanying the pressure fluctuation is drowned out by the engine sound and is difficult for the occupant to recognize. It shall be set. By setting the vehicle condition to a condition where the current engine speed is lower than the predetermined engine speed, the noise caused by the pressure fluctuation makes noise to the occupants in the vehicle interior when the engine speed is low and quiet. Can be suppressed.

Further, it is preferable that the control device 50 controls the actuator 16 so as to expand the flow path cross-sectional area in the inflow side passage 154a when the acceleration of the vehicle exceeds a predetermined acceleration. The control device 50 acquires the acceleration information of the vehicle from the vehicle ECU 60. The vehicle ECU 60 can acquire acceleration information detected by an acceleration detection device such as an automobile gyro sensor. When this determination process is adopted, the predetermined acceleration is preferably set based on experimental results or empirical rules, and the sound due to pressure fluctuation is drowned out by the running sound and engine sound due to acceleration and recognized by the occupants in the vehicle interior. It is assumed that the acceleration is set so that it is difficult to do. By setting the vehicle condition to a condition where the current acceleration of the vehicle exceeds the predetermined acceleration, the purge flow rate can be increased when the noise caused by pressure fluctuations is not felt by the occupants due to the engine noise and running noise caused by the acceleration. Purge performance can be demonstrated without squeezing.

The action and effect brought about by the flow rate adjusting device of the first embodiment will be described. The flow rate adjusting device operates the purge valve 15, the actuator 16 for driving the flow rate adjusting valve 161 for adjusting the flow path cross-sectional area in the inflow side passage 154a located on the canister 13 side of the valve body 152, and the actuator 16. A control device 50 for controlling is provided. The control device 50 controls the actuator 16 so as to narrow the passage cross-sectional area in the inflow side passage 154a when a predetermined vehicle state condition in which noise due to pressure fluctuation can be assumed is satisfied.

According to this flow rate adjusting device, the flow path cross-sectional area in the inflow side passage 154a located on the canister 13 side of the valve body 152 when a predetermined vehicle condition condition in which noise due to pressure fluctuation can be assumed is satisfied. Squeeze. As a result, the fluctuation range of the pressure propagating from the fuel passage 153 in the housing 150 to the canister 13 side through the inflow side passage 154a can be suppressed. In this way, the flow rate adjusting device can reduce noise and the like due to pressure fluctuations.

Further, since the flow rate adjusting device has a configuration in which the fluctuation range of the pressure can be suppressed without having a large chamber, it is possible to suppress the increase in size of the device and improve the vehicle mountability. Further, since the flow rate adjusting device has a configuration for limiting the evaporated fuel flowing into the purge valve 15, it can be applied to the purge valve 15 having a controllable range of a large flow rate. That is, the flow rate adjusting device can provide the evaporated fuel processing device 1 that can control a large flow rate and suppress the pressure fluctuation width in the pipe on the canister 13 side. In other words, the flow rate adjusting device can realize a device having a two-stage flow rate characteristic capable of controlling a low flow rate and controlling a large flow rate.

(Second Embodiment)
The flow rate adjusting device of the second embodiment will be described with reference to FIG. In the second embodiment, the operation of the flow rate adjusting device is different from that in the first embodiment. The configuration, action, and effect not particularly described in the second embodiment are the same as those in the first embodiment.

The control device 50 executes the process according to the flowchart of FIG. Step S220 in FIG. 6 is the same process as step S100 in FIG.

The control device 50 determines in step S200 whether or not the concentration is high based on the canister concentration learning. If it is determined in step S200 that the concentration is lower than the reference value, a process of controlling the actuator 16 so as to operate the flow rate adjusting valve 161 in the throttled state is executed in step S205. By this process, the flow rate regulator performs a small flow rate purging. If it is determined in step S200 that the concentration is higher than the reference value, a process of controlling the actuator 16 so as to operate the flow rate adjusting valve 161 in the fully open state is executed in step S210.

After executing step S205 or step S210, it is determined in step S220 whether or not the predetermined vehicle state condition is satisfied. When it is determined in step S220 that the vehicle state condition is satisfied, a process of operating the flow rate adjusting valve 161 in the throttled state or controlling the actuator 16 so as to maintain the throttled state is executed in step S230. When it is determined in step S220 that the vehicle state condition is not satisfied, a process of operating the flow rate adjusting valve 161 in the fully open state or controlling the actuator 16 so as to maintain the fully open state is executed in step S225.

When learning the canister concentration, the evaporative fuel processing device 1 controls the purge valve 15 so as to gradually increase the duty ratio from the low duty ratio. The evaporative fuel processing device 1 learns the canister concentration while detecting the amount of change in the air-fuel ratio while gradually increasing the purge flow rate by controlling the purge valve 15 in this way. Compared to valves with low flow rate specifications, purge valves with large flow rate specifications have a larger amount of change in flow rate with respect to changes in duty ratio, so depending on the engine used, there is a possibility that the air-fuel ratio will exceed the permissible value and stall. be. In other words, as the flow rate increases, the flow rate fluctuates with respect to the duty ratio, and there is a problem that the air-fuel ratio of the vehicle does not follow and the vehicle stalls.

Therefore, the control device 50 controls the actuator 16 so that the flow rate adjusting valve 161 operates in the throttled state during the canister concentration learning, thereby controlling the valve specifications to have a low flow rate with a small flow rate change during the canister concentration learning, and the engine. Reduce troubles.

Further, after learning the canister concentration, the control device 50 determines in step S210 that it is not the time for learning the canister concentration, and does not execute step S220. As a result, the flow rate adjusting valve 161 is set to the fully open state, so that a large flow rate of purging can be performed and a desired purging function can be exhibited. That is, when the flow rate adjusting device knows the canister concentration and wants to purge a large amount during traveling, the flow path is widened by an actuator and used as a large flow rate valve.

Further, since the flow rate adjusting device can use the function as a large flow rate valve during traveling and when the canister concentration is known, it is effective as a countermeasure against pulsating noise.

(Third Embodiment)
The flow rate adjusting device of the third embodiment will be described with reference to FIGS. 7 and 8. The third embodiment is different from the first embodiment in that the operating voltage of the actuator 16 is suppressed by the low-pass filter 17 to control the throttle state. The configurations, actions, and effects that are not particularly described in the third embodiment are the same as those in the first embodiment, and only the points different from the above-described embodiments will be described below.

As illustrated in FIG. 7, the flow rate regulator of the third embodiment includes a module 18 including a purge valve 15, a low-pass filter 17, and an actuator 16. The voltage of the duty ratio value controlled by the control device 50 is applied to the purge valve 15 and the low-pass filter 17, respectively, and when a predetermined condition is satisfied, the voltage is cut by the low-pass filter 17 and set to a predetermined duty ratio value. A voltage is supplied to the actuator 16. That is, the operating voltage of the actuator 16 is not controlled by the control device 50. The duty ratio supplied to the low-pass filter 17 is supplied to the actuator 16 as a value automatically lowered by the low-pass filter 17.

As shown in FIG. 8, when the increased duty ratio value controlled by the control device 50 exceeds a predetermined value, the low-pass filter 17 lowers the voltage output to the actuator 16 below the supply voltage to the purge valve 15. As a result, the operating voltage applied to the actuator 16 becomes higher than the supply voltage before the duty ratio value is increased. By controlling the supply voltage in this way, the actuator 16 controls the flow rate adjusting valve 161 so as to narrow the flow path cross-sectional area of the inflow side passage 154a. As described above, in the flow rate adjusting device of the third embodiment, the low-pass filter 17 automatically operates the actuator 16 at a certain duty ratio value to change the flow rate. In the flow rate adjusting device of the third embodiment, when the duty ratio value controlled by the control device 50 exceeds the set value, the low-pass filter 17 controls the operating voltage of the actuator 16 so as to suppress the increase in the pressure fluctuation width due to the large flow rate control. Demonstrate the function of cutting. As a result, when the flow rate controlled by the purge valve 15 becomes large, the automatic pressure fluctuation range can be suppressed and noise can be prevented without performing the determination process by the control device 50.

The flow rate adjusting device of the third embodiment is a low-pass filter 17 provided in the middle of an energization path connecting the control device 50 for controlling the duty ratio of the voltage applied to the electromagnetic solenoid unit 151 and the electromagnetic solenoid unit 151 and the actuator 16. And. The low-pass filter 17 is a flow control valve by lowering the voltage output to the actuator 16 when the duty ratio of the voltage applied to the electromagnetic solenoid unit 151 exceeds a predetermined duty ratio value to be lower than the voltage applied to the low-pass filter 17. 161 narrows the flow path cross-sectional area in the inflow side passage 154a.

According to this flow rate adjusting device, when the duty ratio value of the voltage applied to the electromagnetic solenoid unit 151 exceeds the predetermined duty ratio value, the output voltage to the actuator 16 by the low-pass filter 17 is lower than the supply voltage to the purge valve 15. .. As a result, the voltage output to the actuator 16 increases from the supply voltage before the increase in the duty ratio value, so that the cross-sectional area of the flow path in the inflow side passage 154a is narrowed. As a result, the inflow side passage 154a located on the canister 13 side of the valve body 152 is narrowed, so that the fluctuation range of the pressure propagating from the fuel passage 153 to the canister 13 side through the inflow side passage 154a can be suppressed. Therefore, it is possible to provide a flow rate adjusting device capable of reducing noise and the like due to pressure fluctuation without providing the control device 50 with a function of determining a vehicle state condition and performing processing according to the determination result.

(Other embodiments)
Disclosure of this specification is not limited to the illustrated embodiments. The disclosure includes exemplary embodiments and modifications by those skilled in the art based on them. For example, the disclosure is not limited to the combination of parts and elements shown in the embodiment, and can be implemented in various modifications. Disclosure can be carried out in various combinations. The disclosure can have additional parts that can be added to the embodiment. The disclosure includes parts and elements of the embodiment omitted. Disclosures include replacements or combinations of parts, elements between one embodiment and another. The technical scope disclosed is not limited to the description of the embodiments. The technical scope disclosed is indicated by the description of the scope of claims, and should be understood to include all modifications within the meaning and scope equivalent to the description of the scope of claims.

In the above-described embodiment, the control device 50 controls the ratio of the on-time to the time of one cycle formed by the on-time and the off-time of energization, that is, the duty ratio, and supplies electric power to the purge valve 15. However, it is not limited to such a power supply. For example, the purge valve 15 may be controlled by an on / off control that selects either an on state in which a predetermined voltage value is supplied or an off state in which power is not supplied according to a measured value.

In the above-described embodiment, the pressure fluctuation propagating from the fuel passage 153 to the inflow side passage 154a described with reference to FIGS. 3 and 4 occurs only when the purge valve 15 controls the fuel passage 153 in the closed state. It's not something to do. The propagation of the pressure fluctuation shown by the broken line in FIGS. 3 and 4 is a phenomenon that can occur even when the purge valve 15 controls the fuel passage 153 in the open state.

2 ... Engine, 13 ... Canister, 16 ... Actuator 17 ... Low-pass filter, 50 ... Control device, 150 ... Housing 151 ... Electromagnetic solenoid part, 152 ... Valve body, 153 ... Fuel passage 154a ... Inflow side passage, 155 ... Valve seat 161 … Flow rate adjustment valve (flow rate adjustment unit), 1511… Movable core

Claims (7)

A housing (150) having a fuel passage (153) through which evaporative fuel flowing out of the canister (13) due to the intake pressure of the engine (2) flows, and a housing (150).
A valve body that opens and closes the fuel passage so as to switch between an open state that allows the flow of the evaporated fuel away from the valve seat (155) and a closed state that contacts the valve seat and blocks the flow of the evaporated fuel. (152) and
An electromagnetic solenoid unit (151) that generates a driving force that drives a movable core (1511) that is displaced together with the valve body in the axial direction in order to switch between the open state and the closed state.
An actuator (16) for driving a flow rate adjusting unit (161) capable of adjusting the flow path cross-sectional area in the inflow side passage (154a) located on the canister side of the valve body.
A control device (50) that controls the operation of the actuator and
With
The control device is a flow rate adjusting device that controls the actuator so as to narrow the cross-sectional area of the flow path in the inflow side passage when a predetermined vehicle state condition in which noise due to pressure fluctuation can be assumed is satisfied. The flow rate adjusting device according to claim 1, wherein the control device controls the actuator so as to reduce the cross-sectional area of the flow path in the inflow side passage when the vehicle is stopped and the engine is operating. The flow rate adjusting device according to claim 1, wherein the control device controls the actuator so as to reduce the cross-sectional area of the flow path in the inflow side passage when the vehicle speed is lower than a predetermined speed. The flow rate adjusting device according to claim 1, wherein the control device controls the actuator so as to reduce the cross-sectional area of the flow path in the inflow side passage when the rotation speed of the engine is lower than the predetermined rotation speed. The control device according to any one of claims 2 to 4, wherein the control device controls the actuator so as to expand the flow path cross-sectional area in the inflow side passage when the acceleration of the vehicle exceeds a predetermined acceleration. Flow control device. The control device further controls the actuator so as to narrow the cross-sectional area of the flow path in the inflow side passage at the time of learning the concentration of the evaporated fuel in the canister. Any one of claims 1 to 5. The flow rate adjusting device according to the section. A housing (150) having a fuel passage (153) through which evaporative fuel flowing out of the canister (13) due to the intake pressure of the engine (2) flows, and a housing (150).
A valve body that opens and closes the fuel passage so as to switch between an open state that allows the flow of the evaporated fuel away from the valve seat (155) and a closed state that contacts the valve seat and blocks the flow of the evaporated fuel. (152) and
An electromagnetic solenoid unit (151) that generates a driving force that drives a movable core (1511) that is displaced together with the valve body in the axial direction in order to switch between the open state and the closed state.
An actuator (16) for driving a flow rate adjusting unit (161) capable of adjusting the flow path cross-sectional area in the inflow side passage (154a) located on the canister side of the valve body.
A control device (50) that controls the duty ratio of the voltage applied to the electromagnetic solenoid unit, and
A low-pass filter (17) provided in the middle of the energization path connecting the electromagnetic solenoid unit and the actuator,
With
The low-pass filter reduces the voltage output to the actuator with respect to the voltage applied to the electromagnetic solenoid unit when the duty ratio value of the voltage applied to the electromagnetic solenoid unit exceeds a predetermined duty ratio value. As a result, the output voltage to the actuator increases more than before, and the flow rate adjusting unit is a flow rate adjusting device that narrows the cross-sectional area of the flow path in the inflow side passage.

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