Opening / closing device for opening part of vehicle

Abstract

To provide an opening / closing device for an opening part of a vehicle, which has a simple configuration and is advantageous in terms of improving driving stability and riding comfort while suppressing costs.SOLUTION: In the opening / closing device for the opening part of the vehicle, a shape memory alloy 14 that recovers a memorized shape when heated is provided in a gap between a vehicle body hinge 18 and a door hinge 20, a control unit 16 that heats and controls the shape memory alloy 14 is provided, the shape memory alloy 14 is heated by the control unit 16, and the gap between the vehicle body hinge 18 and the door hinge 20 in a state where a getting-on / off opening part is closed by the door is blocked by the shape memory alloy 14 that has recovered the memorized shape, so that the door is restrained in a vehicle body side and the rattling of the door in traveling is suppressed.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an opening and closing device for an opening in a vehicle. [Background technology]

[0002] 2. Description of the Related Art With the aim of improving driving stability and ride comfort, technology has been proposed that suppresses resonance between a door and an opening in a vehicle body by restraining the door, which opens and closes the opening in the vehicle body, with a predetermined restraining force. One such technology disclosed is one in which an engagement pin is provided on the door, an engagement recess is provided on the vehicle body into which the engagement pin is inserted and removed, a shape memory alloy coil is provided in the engagement recess to restrict movement of the engagement pin, and the current supplied to the shape memory alloy coil is controlled based on the acceleration of the vehicle, thereby controlling the restricting force used by the shape memory alloy coil to restrict the engagement pin (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-286344 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-mentioned conventional technology, holes for providing the engagement recesses are formed in the vehicle body, which leads to a decrease in vehicle body rigidity and is disadvantageous in terms of improving handling stability and ride comfort. In addition, there is the disadvantage that the labor costs for forming holes in the vehicle body are high. The present invention has been made in consideration of the above circumstances, and has an object to provide an opening and closing device for an opening in a vehicle that is advantageous in terms of improving driving stability and riding comfort while reducing costs. [Means for solving the problem]

[0005] In order to achieve the above-mentioned object, one embodiment of the present invention is a device for opening and closing an opening in a vehicle, which opens and closes the opening with a door using a hinge mechanism including a vehicle body hinge fixed to the vehicle body, and a door hinge fixed to a door that opens and closes the opening and is swingably connected to the vehicle body hinge, the device comprising: a shape memory alloy that recovers to a memorized shape when heated, provided in the gap between the vehicle body hinge and the door hinge; a heating means for controlling the heating of the shape memory alloy; and a control unit for controlling the heating means, the control unit heats the shape memory alloy, and the vehicle body hinge and the door hinge, which are in a state in which the door is blocking the opening, are closed by the shape memory alloy that has returned to the memorized shape. In addition, one embodiment of the present invention is characterized in that the heating means is provided in contact with the shape memory alloy. In one embodiment of the present invention, at least one of the vehicle body hinge and the door hinge that are adjacent to the heating means is provided with a heat dissipation fin. Moreover, one embodiment of the present invention is characterized in that the hinge mechanism comprises a hinge pin, the vehicle body hinge comprises a pair of vehicle body side connecting plate portions facing each other and through which the hinge pin is inserted, and the door hinge comprises door side connecting plate portions arranged inside or outside the pair of vehicle body side connecting plate portions facing each other and through which the hinge pin is inserted, and the shape memory alloy is arranged in the vehicle body side connecting plate portion facing the door side connecting plate portion around the hinge pin, or in the door side connecting plate portion facing the vehicle body side connecting plate portion around the hinge pin. In addition, one embodiment of the present invention is characterized in that the control unit is configured to include a temperature sensor, the temperature sensor is provided in contact with the shape memory alloy, and the heating control of the shape memory alloy by the control unit is performed based on the temperature of the shape memory alloy detected by the temperature sensor and the vehicle speed. In addition, one embodiment of the present invention is characterized in that the control unit is configured to include a cooling unit that cools the shape memory alloy, and the control unit controls the cooling of the shape memory alloy by the cooling unit based on the temperature of the shape memory alloy detected by the temperature sensor and the vehicle speed. Effect of the Invention

[0006] According to one embodiment of the present invention, a shape memory alloy that recovers to a memorized shape when heated is provided in the gap between the vehicle body hinge and the door hinge, and the shape memory alloy is heated by a heating means that controls the heating of the shape memory alloy. When the vehicle body hinge and the door hinge are in a state in which the door is blocking the entry / exit opening, the gap is filled with the shape memory alloy that has returned to its memorized shape, thereby restraining the door against the vehicle body and suppressing door rattle while driving, which is advantageous in improving the vehicle's handling stability and ride comfort. In addition, since the shape memory alloy is provided in the gap between the vehicle body hinge and the door hinge, there is no need to drill holes in the vehicle body to place the shape memory alloy as in the conventional method, which is advantageous in reducing manufacturing costs. Furthermore, by providing a heating means in contact with the shape memory alloy, the shape memory alloy can be efficiently heated by activating the heating means, allowing the door to be quickly restrained against the vehicle body, which is advantageous in quickly suppressing door rattling while driving and improving handling stability and ride comfort. In addition, by providing heat dissipation fins on at least one of the vehicle body hinge and the door hinge close to the heating means, the heat from the shape memory alloy can be efficiently dissipated through the heat dissipation fins, which quickly releases the state in which the gap between the vehicle body hinge and the door hinge is blocked by the shape memory alloy, which is advantageous for smooth opening and closing of the door. Furthermore, if a shape memory alloy is arranged on the car body side connecting plate portion that faces the door side connecting plate portion around the hinge pin, or on the door side connecting plate portion that faces the car body side connecting plate portion around the hinge pin, the shape memory alloy can be arranged using the car body side connecting plate portion or the door side connecting plate portion around the hinge pin.This eliminates the need for large-scale work such as drilling holes on the car body side, which is advantageous not only for reducing costs but also for making the opening and closing device for the vehicle's entry and exit openings more compact. In addition, if a temperature sensor is provided in contact with the shape memory alloy and the control unit controls the heating of the shape memory alloy based on the temperature of the shape memory alloy detected by the temperature sensor and the vehicle speed, this is advantageous in saving energy by preventing unnecessary heating of the shape memory alloy, and is also advantageous in quickly restraining the door to the vehicle body or releasing the restraint of the door to the vehicle body based on the vehicle speed, which is advantageous in reliably improving handling stability and ride comfort, and in allowing the door to be opened and closed smoothly. In addition, by providing a cooling section for cooling the shape memory alloy and controlling the cooling of the shape memory alloy by the cooling section based on the temperature of the shape memory alloy detected by a temperature sensor by a control section and the vehicle speed, the shape memory alloy can be cooled early and accurately based on the vehicle speed, and the door can be released from its restraint against the vehicle body early, which is advantageous for smooth opening and closing of the door. [Brief description of the drawings]

[0007] [Figure 1] 1 is an explanatory diagram of an opening and closing device for a vehicle opening according to an embodiment, showing a state before the shape memory alloy restores its shape and in which the gap between the vehicle body hinge and the door hinge is not filled with the shape memory alloy. FIG. [Diagram 2] 1 is an explanatory diagram of a device for opening and closing an opening of a vehicle according to an embodiment, showing a state in which a gap between a vehicle body hinge and a door hinge is filled by a shape memory alloy due to a shape recovery action of the shape memory alloy. FIG. [Diagram 3] FIG. 2 is a cross-sectional view of a vehicle body hinge, a door hinge, and a shape memory alloy corresponding to FIG. 1. [Figure 4] 3 is a cross-sectional view of a vehicle body hinge, a door hinge, and a shape memory alloy corresponding to FIG. 2. [Diagram 5] 1 is a cross-sectional view of a vehicle body hinge, a door hinge, and a shape memory alloy, showing a state in which the temperature of the shape memory alloy has fallen below the shape recovery temperature after the shape memory alloy has performed a shape recovery operation. [Figure 6] FIG. 2 is a perspective view of a main portion of a vehicle body hinge to which a shape memory alloy is assembled. [Figure 7]2 is a block diagram showing the configuration of a control system of the opening and closing device for an opening of a vehicle in the embodiment; FIG. [Figure 8] 5 is an explanatory diagram showing the relationship between vehicle speed and temperature and the operation of a heating means and a cooling unit. FIG. [Figure 9] 4 is an operation flowchart of the opening / closing device for an opening of a vehicle according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, a case will be described in which the opening and closing device for an opening in a vehicle of the present invention is applied to a side door of the vehicle. As shown in Figs. 1, 3 and 7, the opening and closing device 10 for a vehicle opening includes a hinge mechanism 12, a shape memory alloy 14, a control unit 16 and a heat generating unit 24 constituting a heating means. The hinge mechanism 12 is provided to pivotally connect the vehicle body and the door so that the entrance / exit opening can be opened and closed by the door. The hinge mechanism 12 includes a vehicle body hinge 18 attached to the vehicle body, a door hinge 20 attached to the door, and a hinge pin 22, all of which are made of steel.

[0009] As shown in FIG. 1, the vehicle body hinge 18 comprises a pair of vehicle body side mounting plate portions 1802 spaced apart vertically, a pair of vehicle body side connecting plate portions 1804 standing up from opposing ends of the vehicle body side mounting plate portions 1802, and a connecting plate portion 1806 connecting the pair of vehicle body side connecting plate portions 1804. The pair of vehicle body side connecting plate portions 1804 have outer surfaces 1804A facing in directions away from each other. Bolt insertion holes 1808 for mounting to the vehicle body are formed through the pair of vehicle body side mounting plate portions 1802, and as shown in Fig. 3, hinge pin insertion holes 1810 are formed through the pair of vehicle body side connecting plate portions 1804, and as shown in Figs. 1 and 6, a plurality of heat dissipation fins 1812 extending in the vertical direction are provided at intervals from each other at the vehicle body side connecting plate portion 1804 location of the hinge pin insertion holes 1810. The heat dissipation fins 1812 are provided at a location of the vehicle body hinge 18 close to the heat generating portion 24.

[0010] As shown in FIG. 3, at opposing positions of a pair of vehicle body side connecting plate portions 1804, an accommodating recess 1814 is provided in an outer surface 1804A in an open manner, the accommodating recess 1814 being coaxial with the hinge pin insertion hole 1810 and having an inner diameter larger than that of the hinge pin insertion hole 1810. In addition, the heating portion 24 and the temperature sensor 26 are arranged at locations spaced apart circumferentially from the hinge pin insertion holes 1810 of the pair of vehicle body side connecting plate portions 1804, spanning from mutually spaced apart locations of the pair of vehicle body side connecting plate portions 1804 to the accommodating recess 1814.

[0011] As shown in FIG. 1, the door hinge 20 includes a door-side mounting plate portion 2002 that is elongated in the width direction of the door to be attached to the door, and a pair of door-side connecting plate portions 2004 that stand up from both the top and bottom sides of the door-side mounting plate portion 2002 and are positioned outside a pair of vehicle-side connecting plate portions 1804. The pair of door side connecting plate portions 2004 have inner surfaces 2004A facing each other. The door side mounting plate portion 2002 is provided with a bolt insertion hole 2006 for mounting to the door, and as shown in FIG. 3, the pair of door side connecting plate portions 2004 are provided with hinge pin insertion holes 2008. As shown in Figures 1 and 3, the hinge pin 22 is inserted into the hinge pin insertion holes 1810, 2008 of a pair of vehicle body side connecting plate portions 1804 and a pair of door side connecting plate portions 2004, and is positioned in the hinge pin insertion holes 1810, 2008 via the large diameter portions 2202 at both ends of the hinge pin 22 so that it cannot fall out, thereby forming the hinge mechanism 12 and allowing the entry / exit opening to be opened and closed by the door.

[0012] As shown in FIG. 3, the shape memory alloy 14 is accommodated in the accommodation recesses 1814 of the pair of vehicle body side connecting plate portions 1804 around the hinge pin 22, and a pair of shape memory alloys 14 are provided. That is, the pair of shape memory alloys 14 are disposed around the hinge pin 22 at a location of the vehicle body side connecting plate portion 1804 that faces the door side connecting plate portion 2004 . As shown in Figures 3 and 6, when the shape memory alloy 14 is placed in the accommodating recess 1814, the portion of the shape memory alloy 14 located on the inner surface 2004A of the door side connecting plate portion 2004 is located approximately on the same plane as the outer surface 1804A of the vehicle body side connecting plate portion 1804. The shape memory alloy 14 performs a shape recovery operation in which it recovers to a previously memorized shape when the temperature of the shape memory alloy 14 reaches or exceeds a predetermined shape recovery temperature Ts. Furthermore, at a temperature below the shape recovery temperature Ts, the shape memory alloy 14 maintains its previous shape unless a pressing force is applied thereto, and can be deformed by the application of a pressing force. In this embodiment, the upper and lower shape memory alloys 14 are arranged in contact with the heating portion 24 and the temperature sensor 26, respectively, and perform shape recovery operation when heated by the heating portion 24 to a temperature equal to or higher than the shape recovery temperature Ts, while at temperatures below the shape recovery temperature Ts, the shape memory alloy 14 can be deformed by a pressing force applied thereto. As such a shape memory alloy 14, various conventionally known shape memory alloys such as Ti-Ni based shape memory alloys can be used.

[0013] On the other hand, when the pair of shape memory alloys 14 are heated by the heating element 24 with the boarding / alighting opening blocked by the door and the pair of shape memory alloys 14 reach or exceed their shape recovery temperature Ts, as shown in Figure 4, the pair of shape memory alloys 14 perform a shape recovery operation, causing the pair of shape memory alloys 14 to deform in an elongating direction along the longitudinal direction of the hinge pin 22 between the outer surfaces 1804A of the pair of vehicle body side connecting plate portions 1804 and the inner surfaces 2004A of the pair of door side connecting plate portions 2004, and the deformation of the pair of shape memory alloys 14 acts in a direction separating the vehicle body side connecting plate portion 1804 and the door side connecting plate portion 2004. 2, the pair of vehicle body side connecting plate portions 1804 are sandwiched by the pair of door side connecting plate portions 2004 via the pair of shape memory alloys 14, and the pair of vehicle body side connecting plate portions 1804 and the pair of door side connecting plate portions 2004 are integrated together. In other words, the gap between the pair of vehicle body side connecting plate portions 1804 and the pair of door side connecting plate portions 2004 is filled by the shape memory alloys 14. In this way, the gap between the pair of vehicle body side connecting plate portions 1804 and the pair of door side connecting plate portions 2004 is filled with the shape memory alloy 14, thereby restraining the doors to the vehicle body side, thereby suppressing rattling of the doors while driving.

[0014] Next, the configuration of the control system will be described. As shown in FIG. 7, the opening and closing device 10 for a vehicle entrance / exit opening portion includes a cooling portion 28, a power source 30, a changeover switch 32, and a control device 34 in addition to the heat generating portion 24 and temperature sensor 26 described above. The heat generating portion 24 is provided on the vehicle body side connecting plate portion 1804 as described above, and in the present invention, is configured as a heater that heats the shape memory alloy 14 when an electric current is supplied thereto. The temperature sensor 26 is provided on the vehicle body side connecting plate portion 1804 as described above, detects the temperature T of the shape memory alloy 14, and supplies the generated temperature signal ST to the control device . The cooling section 28 cools the shape memory alloy 14 . In this embodiment, the cooling section 28 is arranged in a location on the vehicle body near the shape memory alloy 14, and is configured as a fan that, when an electric current is supplied, blows cooling air onto the shape memory alloy 14 and the location of the vehicle body side connecting plate section 1804 where the shape memory alloy 14 is arranged, i.e., the location of the heat dissipation fin 1812 of the vehicle body side connecting plate section 1804. As such a fan, a fan constituting an air conditioner may be used, or a dedicated fan may be provided. The power supply 30 supplies current to the heat generating section 24 and the cooling section 28 via a changeover switch 32. Any power supply may be used as the power supply 30, such as an auxiliary battery mounted on the vehicle. The changeover switch 32 can be switched between the following three states under the control of the control device . First state: A current is supplied from the power supply 30 to the heating portion 24 . Second state: current from the power supply 30 is supplied to the cooling section 28 . Third state: The supply of current from the power supply 30 to the heating section 24 and the cooling section 28 is stopped. Therefore, it is prohibited for the current from the power supply 30 to be supplied to both the heat generating portion 24 and the cooling portion 28 . The control device 34 controls the shape recovery operation of the shape memory alloy 14 by controlling the changeover switch 32 based on a vehicle speed signal SV indicating the vehicle speed supplied from a vehicle speed sensor not shown and a temperature signal ST supplied from the temperature sensor 26, thereby controlling the temperature T of the shape memory alloy 14. In this embodiment, the control unit 16 includes a temperature sensor 26, a cooling unit 28, a power source 30, a changeover switch 32, and a control device 34, and the control unit 16 is provided on the vehicle body side.

[0015] Next, the control of the control device 34 will be specifically described with reference to FIG. 8, the horizontal axis indicates the vehicle speed V, and the vertical axis indicates the temperature T of the shape memory alloy 14, and the vehicle speed V and the temperature T are supplied to the control device 34 by the above-mentioned vehicle speed signal SV and temperature signal ST. In FIG. 8, the symbol VL on the horizontal axis indicates a low-speed threshold value on the low side of the vehicle speed V, and the symbol VH indicates a high-speed threshold value on the high side of the vehicle speed V, and they are set so that the low-speed threshold value VL<the high-speed threshold value VH. Also, the symbol Ts on the vertical axis is the shape recovery temperature of the shape memory alloy 14, the symbol TL is the lower limit temperature, and the symbol TH is the upper limit temperature, which are set so that the lower limit temperature TL<shape recovery temperature Ts<upper limit temperature TH. Moreover, the range of vehicle speed V between the low speed threshold value VL and the high speed threshold value VH (shown by hatching in FIG. 8) is a threshold region ΔV. The threshold region ΔV indicates the range of vehicle speeds V at which the control device 34 maintains the state of the change-over switch 32 in the previous state, in other words, the range at which the on / off operation of the heating section 24 and the cooling section 28 is maintained in the previous state.

[0016] The control device 34 controls the changeover of the changeover switch 32 according to the vehicle speed V and the temperature T of the shape memory alloy 14 as follows. 1) Vehicle speed V>high-speed threshold VH, and temperature T of shape memory alloy 14<upper limit temperature TH The control device 34 switches the change-over switch 32 so that current is supplied to the heating portion 24 , whereby the gap between the body side connecting plate portion 1804 and the door side connecting plate portion 2004 is blocked by the shape memory alloy 14 . Therefore, when the vehicle is traveling at a speed equal to or higher than the high speed threshold value VH, the door is restrained toward the vehicle body, thereby improving the driving stability and the riding comfort.

[0017] 2) Vehicle speed V>high-speed threshold value VH, and temperature T of shape memory alloy 14 ≧upper limit temperature TH The control device 34 switches the changeover switch 32 so that no current is supplied to the heating portion 24 . As a result, the gap between the vehicle body side connecting plate portion 1804 and the door side connecting plate portion 2004 is kept sealed by the shape memory alloy 14, and unnecessary current consumption by the heating portion 24 is suppressed. Therefore, in this case as well, as in the case of 1), when the vehicle is traveling at a speed equal to or higher than the high speed threshold value VH, the door is restrained against the vehicle body, thereby improving the driving stability and ride comfort.

[0018] 3) Vehicle speed V<low speed threshold VL and temperature T of shape memory alloy 14>lower limit temperature TL The control device 34 switches the change-over switch 32 so that current is supplied to the cooling section 28, thereby cooling the shape memory alloy 14. Eventually, when the shape memory alloy 14 falls below its shape recovery temperature Ts, the shape memory alloy 14 becomes deformable, the state in which the gap between the vehicle body side connecting plate section 1804 and the door side connecting plate section 2004 is no longer blocked by the shape memory alloy 14, and the state in which the door is no longer restrained by the vehicle body side. Therefore, when the vehicle speed V falls below the low speed threshold VL and stopping is expected, the state in which the gap between the vehicle body side connecting plate portion 1804 and the door side connecting plate portion 2004 is blocked by the shape memory alloy 14 is released early prior to the vehicle stopping, thereby enabling the door to be opened and closed smoothly after the vehicle stops.

[0019] 4) Vehicle speed V<low-speed threshold VL, and temperature T of shape memory alloy 14≦lower limit temperature TL The control device 34 switches the changeover switch 32 so that no current is supplied to the cooling unit 28 . This helps to reduce unnecessary current consumption by the cooling unit 28. Therefore, in this case as well, as in case 2), when the vehicle speed V falls below the low speed threshold VL and stopping is expected, the state in which the gap between the vehicle body side connecting plate portion 1804 and the door side connecting plate portion 2004 is blocked by the shape memory alloy 14 is released early prior to the vehicle stopping, thereby enabling the door to be opened and closed smoothly after the vehicle stops.

[0020] 5) Low speed threshold value VL ≦ vehicle speed V ≦ high speed threshold value VH (Vehicle speed V is within the threshold range ΔV) If there were a single threshold value for the vehicle speed V for switching the changeover switch 32, when the vehicle speed V increases or decreases around the threshold value, the control device 34 would frequently control the changeover switch 32, which would be disadvantageous in stabilizing the control of the temperature T of the shape memory alloy 14. Therefore, in this embodiment, the changeover switch 32 is switched over using two thresholds, a low-speed threshold VL and a high-speed threshold VH. Therefore, even if the vehicle speed V fluctuates within the range between the low speed threshold VL and the high speed threshold VH (within the threshold region ΔV), the control device 34 maintains the state of the change-over switch 32 in the immediately previous state, thereby stabilizing the control of the change-over switch 32 and being advantageous in stabilizing the control of the temperature T of the shape memory alloy 14.

[0021] Next, the operation of the control device 34 will be described with reference to the operation flowchart of FIG. In the following, we will explain the operation of the changeover switch 32 when the vehicle speed V falls below the threshold region ΔV, i.e., when it is determined that the vehicle speed V is less than the low-speed threshold value VL, and when the vehicle speed V exceeds the threshold region ΔV, i.e., when it is determined that the vehicle speed V is greater than the high-speed threshold value VH. On the other hand, as described above, when it is determined that the vehicle speed V is within the threshold region ΔV, the state of the changeover switch 32 is not changed but is maintained as it was immediately before. Therefore, for the sake of simplicity, the operation when the vehicle speed V is within the threshold region ΔV is omitted from the operation flowchart in FIG. 9 and the following description.

[0022] First, the control device 34 judges whether or not the temperature T of the shape memory alloy 14 is equal to or lower than the lower limit temperature TL (step S10). If the determination in step S10 is negative, that is, if the temperature T of the shape memory alloy 14 is higher than the lower limit temperature TL, it is determined whether or not the temperature T of the shape memory alloy 14 is equal to or higher than the upper limit temperature TH (step S12). If the determination in step S12 is negative, that is, if the temperature T of the shape memory alloy 14 is higher than the lower limit temperature TL and lower than the upper limit temperature TH, the control device 34 determines whether or not the vehicle speed V is less than the low speed threshold value VL (step S14). If the determination in step S14 is negative, that is, if the vehicle speed V is greater than the low speed threshold VL, the control device 34 controls the changeover switch 32 to supply current to the heat generating portion (heating means) 24 to activate it (step S16), and then returns to step S10. As a result, when the shape memory alloy 14 reaches the shape recovery temperature Ts, the gap between the vehicle body side connecting plate portion 1804 and the door side connecting plate portion 2004 is filled by the shape memory alloy 14, and the door is restrained to the vehicle body side.

[0023] On the other hand, if the determination in step S14 is positive, that is, if the vehicle speed V is below the low speed threshold VL, the control device 34 controls the change-over switch 32 to supply current to the cooling unit 28 to activate it (step S18), and then returns to step S10. As a result, when the temperature T of the shape memory alloy 14 falls below the shape recovery temperature Ts, the state in which the gap between the vehicle body side connecting plate portion 1804 and the door side connecting plate portion 2004 is no longer blocked by the shape memory alloy 14, and the door is released from the constraint on the vehicle body.

[0024] Moreover, if the determination in step S12 is positive, that is, if the temperature T of the shape memory alloy 14 is equal to or higher than the upper limit temperature TH, the control device 34 controls the changeover switch 32 to stop the supply of current to the heating portion 24 (step S20). Next, the control device 34 determines whether or not the vehicle speed V is less than the low speed threshold value VL (step S22). If the determination in step S22 is positive, that is, if the vehicle speed V is lower than the low speed threshold value VL, the process proceeds to step S18 and then returns to step S10. If the determination in step S22 is negative, that is, if the vehicle speed V is higher than the low speed threshold VL, the process returns to step S10.

[0025] Moreover, if the determination in step S10 is positive, that is, if the temperature T of the shape memory alloy 14 is equal to or lower than the lower limit temperature TL, the control device 34 controls the changeover switch 32 to stop the supply of current to the cooling unit 28 (step S24). Next, the control device 34 determines whether or not the vehicle speed V is less than the high speed threshold value VH (step S26). If the determination in step S26 is positive, that is, if the vehicle speed V is lower than the high speed threshold value VH, the process returns to step S10. If the determination in step S26 is negative, that is, if the vehicle speed V is greater than the high speed threshold value VH, the control device 34 controls the changeover switch 32 to supply current to the heating portion 24 (step S28), and the process returns to step S10. As a result, when the shape memory alloy 14 reaches the shape recovery temperature Ts, the gap between the vehicle body side connecting plate portion 1804 and the door side connecting plate portion 2004 is filled by the shape memory alloy 14, and the door is restrained to the vehicle body side.

[0026] Next, the function and effect of the opening and closing device 10 will be described. As shown in Figures 1 and 3, when both of the pair of shape memory alloys 14 are below their shape recovery temperatures Ts, when the boarding and alighting opening is blocked by the door, the weight of the door causes the upper door side connecting plate portion 2004 to be placed on the upper vehicle body side connecting plate portion 1804, and a gap S is formed between the lower door side connecting plate portion 2004 and the lower vehicle body side connecting plate portion 1804. On the other hand, when the vehicle is traveling and the vehicle speed V exceeds the threshold region ΔV, the pair of shape memory alloys 14 is heated by the heating section (heating means) 24, and when the pair of shape memory alloys 14 reaches or exceeds the shape recovery temperature Ts, as shown in Figures 2 and 4, the pair of shape memory alloys 14 performs a shape recovery operation, the pair of shape memory alloys 14 extends along the longitudinal direction of the hinge pin 22, and the pair of vehicle body side connecting plate portions 1804 are clamped by the pair of door side connecting plate portions 2004 via the pair of shape memory alloys 14, and the gap S between the pair of vehicle body side connecting plate portions 1804 and the pair of door side connecting plate portions 2004 is sealed. Therefore, by restraining the door against the vehicle body, rattling of the door while driving is suppressed, improving handling stability and ride comfort.

[0027] Furthermore, when the vehicle speed V falls below the threshold region ΔV while the vehicle is traveling, the heating portion 24 stops generating heat and the pair of shape memory alloys 14 falls below the shape recovery temperature Ts, whereby the pair of shape memory alloys 14 become deformable, the gap S between the pair of vehicle body side connecting plate portions 1804 and the pair of door side connecting plate portions 2004 is released from its blocked state, the door becomes openable and closable via the hinge mechanism 12, and the door is released from its constraint on the vehicle body side. When the gap S between the pair of vehicle body side connecting plate portions 1804 and the pair of door side connecting plate portions 2004 is released from the blocked state, as shown in Figure 1, the weight of the door causes the inner surface 2004A of the upper door side connecting plate portion 2004 to abut against the outer surface 1804A of the upper vehicle body side connecting plate portion 1804, and the force from the inner surface 2004A of the upper door side connecting plate portion 2004 acts on the shape memory alloy 14 arranged above, so that the shape memory alloy 14 arranged above is accommodated in the accommodating recess 1814. Furthermore, as shown in FIG. 5, a gap S is formed between the inner surface 2004A of the lower door side connecting plate portion 2004 and the outer surface 1804A of the lower vehicle body side connecting plate portion 1804, so that no external force acts on the shape memory alloy 14 arranged below, and the shape memory alloy 14 arranged below is maintained in its previous stretched shape (the shape that was previously memorized).

[0028] According to this embodiment, a shape memory alloy 14 that recovers to a memorized shape when heated is provided in the gap S between the vehicle body hinge 18 and the door hinge 20, and the shape memory alloy 14 is heated by a heating unit 24 that controls the heating of the shape memory alloy 14. The gap S between the vehicle body hinge 18 and the door hinge 20 when the door is blocking the boarding and alighting opening is blocked by the shape memory alloy 14 that has returned to its memorized shape, thereby restraining the door against the vehicle body and suppressing rattling of the door while driving, which is advantageous in improving the vehicle's handling stability and ride comfort. In addition, since the shape memory alloy 14 is provided in the gap between the vehicle body hinge 18 and the door hinge 20, there is no need to drill holes in the vehicle body to place the shape memory alloy 14 as in the conventional method, which is advantageous in reducing labor costs.

[0029] In addition, in this embodiment, since the heating portion 24 is provided in contact with the shape memory alloy 14, the shape memory alloy 14 can be efficiently heated by operating the control portion 16 (control device 34), and the gap S between the vehicle body hinge 18 and the door hinge 20 can be quickly filled by the shape memory alloy 14 which has returned to its memorized shape. Therefore, the door can be restrained against the vehicle body at an early stage, which is advantageous in preventing rattling of the door while driving and improving driving stability and ride comfort.

[0030] In addition, in this embodiment, heat dissipation fins 1812 are provided on at least one of the vehicle body hinge 18 and the door hinge 20, which are adjacent to the heat-generating portion 24, which is advantageous in efficiently dissipating heat from the shape memory alloy 14 through the heat dissipation fins 1812. Therefore, the shape memory alloy 14 can be efficiently cooled to a temperature below the shape recovery temperature Ts, which quickly releases the state in which the gap S between the vehicle body hinge 18 and the door hinge 20 is blocked by the shape memory alloy 14, which is advantageous for smooth opening and closing of the door.

[0031] Furthermore, in this embodiment, the shape memory alloy 14 is arranged in the gap S between the door side connecting plate portion 2004 and the vehicle body side connecting plate portion 1804 around the hinge pin 22. Therefore, the shape memory alloy 14 can be arranged by utilizing the vehicle body side connecting plate portion 1804 around the hinge pin 22. This not only eliminates the need for the work of forming holes on the vehicle body side, but is also advantageous in terms of reducing labor costs, and is advantageous in terms of making the opening and closing device 10 for the vehicle's boarding and alighting openings more compact.

[0032] In addition, in this embodiment, the control unit 16 is configured to include a temperature sensor 26, which is provided in contact with the shape memory alloy 14, and the heating control of the shape memory alloy 14 by the control unit 16 is performed based on the temperature T of the shape memory alloy 14 detected by the temperature sensor 26 and the vehicle speed V of the vehicle. Therefore, since heating control of shape memory alloy 14 is performed based on the temperature T of shape memory alloy 14 and the vehicle speed V of the vehicle, it is advantageous for saving energy by preventing unnecessary heating of shape memory alloy 14, and it is also advantageous for quickly restraining the door to the vehicle body or releasing the restraint of the door to the vehicle body based on the vehicle speed V, which is advantageous for quickly improving handling stability and ride comfort, and for smoothly opening and closing the door.

[0033] In addition, in this embodiment, the control unit 16 is configured to include a cooling unit 28 that cools the shape memory alloy 14, and the control unit 16 controls the cooling of the shape memory alloy 14 by the cooling unit 28 based on the temperature T of the shape memory alloy 14 detected by the temperature sensor 26 and the vehicle speed V of the vehicle. Therefore, the shape memory alloy 14 can be cooled early and accurately based on the temperature T of the shape memory alloy 14 and the vehicle speed V of the vehicle, and the door can be released from its restraint on the vehicle body early based on the vehicle speed V, which is advantageous for smooth opening and closing of the door.

[0034] In this embodiment, the shape memory alloy 14 is disposed on the vehicle body side connecting plate portion 1804 facing the door side connecting plate portion 2004 around the hinge pin 22. However, the shape memory alloy 14 may be disposed on the door side connecting plate portion 2004 at a location facing the vehicle body side connecting plate portion 1804 around the hinge pin 22. In this case, the heat dissipation fin 1812 may be provided on the door hinge 20 close to the heat generating portion 24. However, in the case of this embodiment, since it is sufficient to arrange the heating unit 24 and the temperature sensor 26 on the vehicle body side connecting plate portion 1804, there is no need to run the wiring connected to the heating unit 24 from the power source 30 and the changeover switch 32 arranged on the vehicle body side, and the wiring connected to the temperature sensor 26 from the control device 34 from the vehicle body side to the door side. It is sufficient to run the wiring on the vehicle body side, which is advantageous in terms of simplifying the wiring and improving workability. [Explanation of symbols]

[0035] 10 Switchgear 12 Hinge mechanism 14 Shape memory alloy 16 Control section 18 Body hinge 1802 Vehicle body side mounting plate 1804 Vehicle side connecting plate 1804A Exterior 1806 Connection plate 1808 Bolt insertion hole 1810 Hinge pin insertion hole 1812 Heat dissipation fin 1814 Recessed part 20 Door hinge 2002 Door side mounting plate 2004 Door side connecting plate 2004A Inside 2006 Bolt insertion hole 2008 Hinge pin insertion hole 22 Hinge pin 2202 Large diameter section 24 Heat generating unit (heating means) 26 Temperature Sensor 28 Cooling section 30 power supply 32 Changeover switch 34 Control device

Claims

1. A device for opening and closing an opening of a vehicle, the device comprising: a vehicle body hinge fixed to a vehicle body; and a door hinge fixed to a door that opens and closes an opening of the vehicle body and swingably connected to the vehicle body hinge, the device opening and closing the opening with the door using a hinge mechanism comprising: a shape memory alloy that recovers to a memorized shape by being heated is provided in a gap between the vehicle body hinge and the door hinge; A heating means for controlling heating of the shape memory alloy and a control unit for controlling the heating means are provided; The control unit heats the shape memory alloy, and the gap between the vehicle body hinge and the door hinge in a state where the opening is closed by the door is blocked by the shape memory alloy that has returned to the memorized shape. A device for opening and closing an opening in a vehicle.

2. The heating means is provided in contact with the shape memory alloy.

2. The opening and closing device for a vehicle opening according to claim 1.

3. a heat dissipation fin is provided on at least one of the vehicle body hinge and the door hinge adjacent to the heating means; 3. The opening and closing device for a vehicle opening according to claim 2.

4. the hinge mechanism includes a hinge pin; the vehicle body hinge includes a pair of vehicle body side connecting plate portions facing each other and having the hinge pin inserted therebetween, the door hinge includes door-side connecting plate portions that are arranged on the inner side or the outer side of the pair of vehicle body-side connecting plate portions and face each other, and through which the hinge pin is inserted, The shape memory alloy is disposed on a vehicle body side connecting plate portion facing the door side connecting plate portion around the hinge pin, or on a door side connecting plate portion facing the vehicle body side connecting plate portion around the hinge pin.

2. The opening and closing device for a vehicle opening according to claim 1.

5. The control unit includes a temperature sensor, The temperature sensor is provided in contact with the shape memory alloy, The control unit controls the heating of the shape memory alloy based on the temperature of the shape memory alloy detected by the temperature sensor and the vehicle speed of the vehicle.

2. The opening and closing device for a vehicle opening according to claim 1.

6. The control unit includes a cooling unit that cools the shape memory alloy, The control unit controls the cooling of the shape memory alloy by the cooling unit based on the temperature of the shape memory alloy detected by the temperature sensor and the vehicle speed of the vehicle.

2. The opening and closing device for a vehicle opening according to claim 1.

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