GRILLE SHUTTER APPARATUS

A grille shutter apparatus includes: a plurality of movable fins that are arranged in parallel and are respectively rotatably supported; a first link mechanism that is independently provided between two adjacent movable fins and forms a series driving force transmission path of both movable fins; a driving section that is provided at one end of the series driving force transmission path and drives the plurality of movable fins to be rotated; a control unit configured to control the driving section and detecting an operation state of the driving section; and a second link mechanism that is connected to the one end and the other end of the series driving force transmission path and is moved in conjunction with the one end and the other end by being synchronized therewith.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority under 35 U.S.C. §119 to Japanese Patent Application 2015-089597, filed on Apr. 24, 2015, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

This disclosure relates to a grille shutter apparatus.

BACKGROUND DISCUSSION

A grille shutter apparatus configured to control a flow rate of air flowing from a grille opening portion into an engine room based on opening and closing operations of a shutter mechanism provided at the grille opening portion arranged at a front portion of a vehicle body is disclosed in the related art. For example, in a grille shutter apparatus described in JP2014-80071A (hereinafter referred to as Reference 1) a shutter mechanism is formed such that a plurality of movable fins are aligned within a frame provided on the inside of a grille opening portion. Then, a flow path formed on the inside of the frame may be opened and closed by rotating each of the movable fins about a rotary shaft by driving a motor. According to such a configuration, for example, in a case in which the vehicle is running at a high speed, an aerodynamic performance (for example, “Cd value” and the like) can be enhanced by limiting an inflow of the air flowing into the inside of the engine room by causing the shutter mechanism to be in a closed state. In addition, when an engine starts, warm-up time of an engine can be shortened by suppressing the flow rate of the air introduced into a radiator. Then, if an engine temperature has a tendency to increase, the engine temperature can be controlled at an appropriate temperature by increasing the flow rate flowing into the engine room by causing the shutter mechanism to be in the closed state.

In addition, in the grille shutter apparatus of the related art described above, a link mechanism independent for every two adjacent movable fins is provided to operate each of the movable fins in conjunction with each other and forms a series driving force transmission path. Then, a pressing section that is operated based on the operation of the movable fins is provided in the furthest end portion of the driving force transmission path and the pressing section is configured to press a detector (for example, a limit switch and the like) provided on a driving section side. The detector is operated and thereby it is possible to confirm whether each of the movable fins is normally operated.

However, according to the configuration described above, in order to confirm the operation state of each of the movable fins, the detector is necessarily required to be provided in the furthest end portion of the driving force transmission path. Therefore, if the detector fails for some reason, it becomes impossible to detect the operation state of each of the movable fins. In addition, the grille shutter apparatus becomes expensive and has a complicated structure by providing the detector and, in this regard, it leaves room for improvement.

SUMMARY

Thus, a need exists for a grille shutter apparatus which is not suspectable to the drawback mentioned above.

A first aspect of thus disclosure is directed to a grille shutter apparatus including a plurality of movable fins that are arranged in parallel and are respectively rotatably supported; a first link mechanism that is independently provided between two adjacent movable fins and forms a series driving force transmission path of both movable fins; a driving section that is provided at one end of the series driving force transmission path and drives the plurality of movable fins to be rotated; a control unit configured to control the driving section and detecting an operation state of the driving section; and a second link mechanism that is connected to the one end and the other end of the series driving force transmission path and is moved in conjunction with the one end and the other end by being synchronized therewith.

DETAILED DESCRIPTION

Hereinafter, embodiments embodying this disclosure will be described referring to drawings.

In a vehicle1illustrated inFIG. 1, a radiator5for cooling an engine4is accommodated in an engine room3formed on the inside of a vehicle body2. A grille opening portion7communicating an external space at the front of the vehicle and an internal space of the vehicle body2is formed at a front portion (left end portion in the view) of the vehicle body2. Then, the radiator5is arranged at the front of the engine4such that air that flows from the grille opening portion7into the engine room3is blowing against the radiator5.

In addition, a fan6is provided on a rear side (right side in the view) of the radiator5. As the fan6rotates, the air efficiently flows to the radiator5.

In the embodiment, the grille opening portion7is formed on a lower side of a bumper8. In addition, at an opening end7aof the grille opening portion7, front grilles9providing a design surface (lower grille) are attached. Then, a grille shutter apparatus10capable of controlling the flow rate of the air flowing from the grille opening portion7into the engine room3is provided in the vehicle1of the embodiment.

In further detail, the grille shutter apparatus10includes a shutter mechanism12having a plurality of movable fins11and an actuator13driving the shutter mechanism12to be opened and closed.

As illustrated inFIGS. 2 and 3, the shutter mechanism12of the embodiment includes a frame14formed in a substantially rectangular shape extending in a width direction of the vehicle body2. Then, each of the movable fins11is rotatably supported within a framework of the frame14.

In particular, each of the movable fins11includes a rotary shaft15stretched between sidewall portions14L and14R of the frame14and is rotatably supported by the rotary shaft15. In addition, each of the movable fins11includes a fin portion16which can close the framework of the frame14by rotating about the rotary shaft15. Moreover, the shutter mechanism12of the embodiment includes movable fins11A and11B, arranged in two rows parallel to each other in an up-down direction within the framework of the frame14. Then, as illustrated inFIG. 1, the shutter mechanism12of the embodiment is arranged on the inside of the grille opening portion7by fixing an upper end of the frame14to a bumper reinforce17.

That is, the shutter mechanism12of the embodiment is in an open state by rotating each of the movable fins11in a direction (clockwise direction inFIG. 1) to bring the fin portions16in parallel with respect to a flow direction of the air flowing from the grille opening portion7. In addition, the shutter mechanism12is in a closed state by rotating each of the movable fins11in a direction (counterclockwise direction inFIG. 1) to bring the fin portions16perpendicular with respect to the flow direction of the air. Then, if each of the movable fins11is in a rotational position corresponding to a fully-closed state, the framework of the frame14may be closed by overlapping respective ends (fin ends of the fin portions16) of each of the movable fins11adjacent to each other.

On the other hand, as illustrated inFIG. 4, the actuator13drives the shutter mechanism12to be opened and closed by rotating each of the movable fins11using a motor20as a driving source. Then, an operation of the actuator13is controlled by an ECU21which serves as a control unit.

That is, the ECU21controls opening and closing operations of the shutter mechanism12. Then, the grille shutter apparatus10of the embodiment can control the flow rate of the air flowing from the grille opening portion7into the engine room3based on the opening and closing operations of the shutter mechanism12by the rotation of each of the movable fins11.

In further detail, according to the embodiment, the ECU21receives vehicle information signals indicating various vehicle states such as a vehicle speed V and a cooling water temperature Tw of the engine4. Then, the ECU21performs opening and closing control of the shutter mechanism12based on the vehicle information signals.

Specifically, the ECU21recognizes that an ignition switch of the vehicle1is turned on (IG on), that is, the vehicle1is either in a driving state or in a state of preparation for driving by starting communication of each of the vehicle information signals via an in-vehicle network (not illustrated). Then, the ECU21executes known opening and closing control, for example, to maintain the shutter mechanism12in the closed state until the cooling water temperature Tw increases, or to bring the shutter mechanism12to the closed state due to an increase in the vehicle speed V.

In addition, according to the embodiment, the ECU21is connected to a pulse sensor22provided in the actuator13and the ECU21detects an operation amount of the shutter mechanism12based on a pulse signal Sp, which is synchronized with the rotation of the motor20, input from the pulse sensor22. In addition, the ECU21includes a determination section23that determines whether or not the actuator13is normally operated based on the operation amount.

In further detail, as illustrated in the flow chart ofFIG. 5, the ECU21executes the opening and closing operation control (step101) of the shutter mechanism12until the detected operation amount reaches a regulated operation amount corresponding to the fully-open state or the fully-closed state of the shutter mechanism12(step103: YES) while monitoring a time from starting of the opening operation or the closing operation by the shutter mechanism12and monitoring the operation amount of the shutter mechanism12detected based on the pulse signal Sp. Then, the determination section23determines that the opening and closing operations are normally performed (step104) if the time from starting of the opening operation or the closing operation by the shutter mechanism12is within a predetermined time and the operation amount reaches the regulated operation amount.

On the other hand, the determination section23determines that the opening and closing operation control is abnormally performed (step105) if the time from starting of the opening operation or the closing operation by the shutter mechanism12reaches a predetermined time but the operation amount does not reach the regulated operation amount, that is, the shutter mechanism12cannot be confirmed to be in the fully-open state or the fully-closed state (step102: NO). In order to cause the shutter mechanism12to be in the fully-open state or the fully-closed state, the opening and closing operation control is executed again. In addition, details of a so-called retry control will be omitted.

Operation State Confirming Structure

Next, an operation state confirming structure of the shutter mechanism of the embodiment will be described.

As illustrated inFIG. 6, according to the embodiment, both the sidewall portions14L and14R of the frame14include two supporting holes25aand25brespectively corresponding to each of the movable fins11(11A and11B) in positions separated from each other in an up-down direction (up-down direction in the view, seeFIG. 3). Then, as illustrated inFIG. 3, both end portions of the rotary shaft15of each of the movable fins11A and11B are inserted into the supporting holes25aand25b,respectively, so that the movable fins11A and11B are rotatably supported by the frame14in a state in which the fin portions16are arranged on the inside of the framework.

In addition, the shutter mechanism12of the embodiment includes a first link mechanism26connecting between shaft end portions11La and11Lb of each of the movable fins11A and11B. Then, similar to the first link mechanism26, the shutter mechanism12includes a second link mechanism36connecting between shaft end portions11Ra and11Rb of each of the movable fins11A and11B.

In particular, the first link mechanism26has a configuration including a pair of lever members26aand26bfixed to the shaft end portions11La and11Lb of each of the movable fins11A and11B protruding to the outside of the framework of the frame14in a manner of penetrating the sidewall portion14L and a link member26crotatably connected to the end of each of the shaft end portions11La and11Lb.

On the other hand, similar to the first link mechanism26, the second link mechanism36has a configuration including a pair of lever members36aand36bfixed to the shaft end portions11Ra and11Rb of each of the movable fins11A and11B protruding to the outside of the framework of the frame14in a manner of penetrating the sidewall portion14R and a second link member36crotatably connected to the end of each of the shaft end portions11Ra and11Rb.

Then, as illustrated inFIG. 2, the actuator13of the embodiment is configured to drive the shaft end portion11Ra in the movable fin11A disposed on a lower row on the outside of the framework by fixing to the sidewall portion14R of the frame14.

That is, as illustrated inFIG. 7, the shutter mechanism12of the embodiment is configured to form a series driving force transmission path from the movable fin11A arranged at the lower row to the movable fin11B arranged at an upper row via the first link mechanism26. Thus, the movable fins11A and11B are rotated in conjunction with each other based on the driving force transmitted from the shaft end portion11Ra on the right side of the movable fin11A arranged at the lower row to the shaft end portion11La on the left side and from the shaft end portion11Lb on the left side of the movable fin11B arranged at the upper row to the shaft end portion11Ra on the right side.

On the other hand, the second link mechanism36connects the shaft end portion11Ra and the shaft end portion11Rb not via the driving force transmission path formed by the first link mechanism26. Thus, the driving force of the actuator13is directly transmitted from the shaft end portion11Ra to the shaft end portion11Rb and the movable fins11A and11B are moved in conjunction with each other and also rotated by the second link mechanism36.

According to the embodiment described above, the following advantages can be attained.

(1) The shutter mechanism12has the movable fins11A and11B arranged in two rows parallel to one other in the up-down direction within the framework of the frame14. In addition, the shaft end portions11La and11Lb of the movable fins11A and11B adjacent to each other in the up-down direction are connected to each other via the first link mechanism26. Further, the driving force of the actuator13is input to the shaft end portion11Ra on a side opposite to the first link mechanism26of the movable fin11A arranged at the lower row and thereby the series driving force transmission path is formed in the shutter mechanism12. On the other hand, the second link mechanism36connects each of the shaft end portions11Ra and11Rb of the movable fins11A and11B. Thus, the second link mechanism36can be moved in conjunction with each of the shaft end portions11Ra and11Rb of the movable fins11A and11B by being synchronized therewith without abnormal influence on the operation state such as deflection of each movable fin occurring in the driving force transmission path or jamming of foreign matter between the movable fins. Here, the operation state of the shaft end portion11Ra of the movable fin11A can be detected by the ECU21controlling the actuator13. That is, if the rotation of the movable fins11A and11B is inhibited by jamming of the foreign matter, the rotation of at least one of the shaft end portion11Ra of the movable fin11A and the shaft end portion11Rb of the movable fin11B is inhibited. Then, since the operation of the actuator13is inhibited, the ECU21can detect rotation abnormality of each of the movable fins11A and11B. Therefore, it is possible to accurately confirm the operation state of each of the movable fins with a simple structure without a need to provide a detector such as a limit switch in the shaft end portion11Rb of the movable fin11B that is on the other end side of the driving force transmission path. In addition, since the second link mechanism36can transmit the driving force of the actuator13in a path different from the series driving force transmission path, it is possible to further reliably transmit the driving force to each of the movable fins11A and11B.

(2) In addition, the ECU21detects the operation amount of the actuator13by the pulse signal Sp, which is synchronized with the rotation of the motor20, input from the pulse sensor22provided in the actuator13. Then, the determination section23of the ECU21can determine abnormality of each of the movable fins11A and11B by the operation amount. Therefore, it is possible to accurately detect the operation state of each of the movable fins11A and11B with a simple structure.

(3) In addition, the determination section23of the ECU21determines whether the operation amount of the actuator13reaches an operation amount corresponding to the fully-open state and the fully-closed state within a predetermined time. Therefore, it is possible to determine whether each of the movable fins11A and11B fully opens and fully closes the grille opening portion7only by detecting the operation amount of the actuator13.

Moreover, the aforementioned embodiment may be changed as follows.

In the aforementioned embodiment, the air flowing from the grille opening portion7flows into the engine room3formed in the vehicle body2. However, the configuration is not limited to the embodiment and an intake destination of the air may not be the engine room3as long as the intake destination is an inner space of the vehicle body2in which the flow rate of the flowing-in air is controllable based on the opening and closing operations of the shutter mechanism12. That is, for example, it may be a space into which the air flows from the grille opening portion7such as a housing of a heat exchanger such as the radiator5. The grille shutter apparatus10of the embodiment may be applied to a vehicle in which an engine is not mounted to an inner space of a vehicle body on the front of a passenger compartment such as a vehicle in which an engine is disposed at a rear portion or a center of a vehicle body, or an electric vehicle.

In the aforementioned embodiment, the grille opening portion7is formed on the lower side of the bumper8. However, the configuration is not limited to the embodiment and this disclosure may be applied to the grille opening portion7formed on the upper side of the bumper8. That is, the front grille9may be an upper grille.

In the aforementioned embodiment, the first link mechanism26and the second link mechanism36are formed by the pair of the lever members26aand26b,and36aand36bfixed to the shaft end portions11La and11Lb of each of the movable fins11A and11B, and the link member26cand the second link member36crotatably connected to the end of each of the lever members26a,26b,36a,and36b.However, the configuration is not limited to the embodiment and forms of the first link mechanism26and the second link mechanism36configuring the link mechanism may be arbitrarily changed. Then, each of the movable fins11A and11B may be configured to be connected by using a link mechanism other than the first link mechanism26and the second link mechanism36, for example, a gear, a pulley, and the like.

In the aforementioned embodiment, two movable fins11(11A and11B) are arranged parallel to each other. However, the number of the movable fins is not necessarily limited to the embodiment. That is, the series driving force transmission path is formed as a configuration including three or more movable fins11with a configuration, in which the first link mechanism (link and the like) independent for every two adjacent movable fins is provided and the movable fins are moved in conjunction with each other and rotated, and then one end and the other end of the driving force transmission path may be further directly connected by the second link mechanism (link and the like).

For example, a shutter mechanism32illustrated inFIG. 8has three movable fins11A,11B, and11C arranged parallel to each other in the up-down direction within the framework of the frame14. In the shutter mechanism32, the shaft end portion11Ra of the movable fin11A and the shaft end portion11Rb of the movable fin11B, and the shaft end portion11Lb of the movable fin11B and a shaft end portion11Lc of the movable fin11C adjacent in the up-down direction are respectively connected via first link mechanisms26R and26L. Furthermore, the actuator13is fixed to the sidewall portion14R of the frame14and thereby drives the shaft end portion11Ra of the movable fin11A. Then, the shaft end portion11Ra of the movable fin11A and a shaft end portion11Rc of the movable fin11C are directly connected by the second link mechanism36.

In the configuration described above, a series driving force transmission path leading from the movable fin11A at the lower row to the movable fin11B at a middle row via the first link mechanism26R and further from the movable fin11B at the middle row to the movable fin11C at the upper row via the first link mechanism26L is also formed in the shutter mechanism32illustrated inFIG. 8. Then, the second link mechanism36directly connects the movable fin11A at the lower row and the movable fin11C at the upper row not via the series driving force transmission path. Therefore, it is possible to obtain the same advantages as those of the above-described embodiment.

In the aforementioned embodiment, the first link mechanism26connects the shaft end portions11La and11Lb of each of the movable fin11A and11B on the outside of the framework of the frame14. However, the configuration is not limited to the embodiment and as a shutter mechanism42illustrated inFIG. 9, the first link mechanism26may be disposed within the framework of the frame14, that is, the first link mechanism26may connect intermediate portions in the rotary shaft15of each of the movable fins11A and11B.

That is, as long as each of the movable fins is configured to rotate in conjunction with each of the movable fins by including the link mechanism independent for every two adjacent movable fins, the series driving force transmission path is formed irrespective to the arrangement of the link mechanism. However, in a case in which such a configuration is adopted, the rotary shafts15of the movable fins11A and11B are desired not to be divided into plural shaft bodies in the longitudinal direction and be in a state of being rotatable relative to each other. Accordingly, it is possible to obtain the same advantages as those of the above-described embodiment.

In the aforementioned embodiment, the actuator13is fixed to the sidewall portion14R of the frame14and drives the shaft end portion11Ra of the movable fin11A on the outside of the framework of the frame. However, the configuration is not limited to the embodiment and the actuator13may be specifically disposed within the framework of the frame14.

A first aspect of thus disclosure is directed to a grille shutter apparatus including a shutter mechanism including a plurality of movable fins that are arranged in parallel and are respectively rotatably supported; a first link mechanism that is independently provided between two adjacent movable fins and forms a series driving force transmission path of both movable fins; a driving section that is provided at one end of the series driving force transmission path and drives the plurality of movable fins to be rotated; a control unit configured to control the driving section and detecting an operation state of the driving section; and a second link mechanism that is connected to the one end and the other end of the series driving force transmission path and is moved in conjunction with the one end and the other end by being synchronized therewith.

According to the configuration described above, the first link mechanism connects the movable fins in series and forms the driving force transmission path. Therefore, it is possible to move the plurality of movable fins in conjunction with each other by driving one end of the driving force transmission path. On the other hand, one end and the other end of the driving force transmission path are connected by the second link mechanism. Therefore, the second link mechanism connects one end and the other end of the driving force transmission path in conjunction with each other by being synchronized therewith without abnormal influence on the operation state such as deflection of each of the movable fins occurring in the driving force transmission path or jamming of foreign matter between the movable fins. Here, since the operation state of one end can be detected by the control unit via the driving section, it is also possible to detect the operation state of the other end moved in conjunction with one end by being synchronized therewith. That is, if the rotation of the movable fins is inhibited by jamming of the foreign matter, the rotation of at least one of one end and the other end of the driving force transmission path is inhibited. Since the operation of the driving section is inhibited, it is possible to detect rotation abnormality of the movable fin. Therefore, it is possible to accurately confirm the operation state of each of the movable fins with a simple structure without a need to provide a detector such as a limit switch on the other end.

A second aspect of this disclosure is directed to the grille shutter apparatus described above, in which the control unit includes a determination section that detects the operation state of the driving section by an operation amount of the driving section and determines an operation of the shutter mechanism to be abnormal if the operation amount does not reach a predetermined amount.

According to the configuration described above, it is possible to detect abnormality of the operation state of each of the movable fins by detecting the operation amount of the driving section. Thus, it is possible to accurately detect the operation state of each of the movable fins with a simple structure.

A third aspect of this disclosure is directed to the grille shutter apparatus described above, in which the determination section determines the operation of the shutter mechanism to be abnormal if the operation amount of the driving section does not reach an operation amount corresponding to a fully-open state within a predetermined time from starting of an opening operation of the shutter mechanism and determines the operation of the shutter mechanism to be abnormal if the operation amount of the driving section does not reach an operation amount corresponding to a fully-closed state within a predetermined time from starting of a closing operation of the shutter mechanism.

According to the configuration described above, the determination section can detect fully open and fully close of each of the movable fins only by determining whether or not the operation amount of the driving section reaches the operation amount corresponding to the fully-open state and the fully-closed state.

As described above, according to the aspects of this disclosure, it is possible to accurately confirm the operation state of each of the movable fins with a simple structure.