REFRIGERATOR

Abstract

 Provided is a refrigerator including a gasket (22) which brings a housing (11) into close contact with a door (15a). The refrigerator also has: a first closed door mode in which the gasket (22) is strongly pressed on the housing (11) by the actuator (23a) and is thus compressed to improve heat insulating properties of a storage compartment; and a second closed door mode in which the compressed state of the gasket (22) is loosened to reduce a door-opening force. In the first closed door mode in which the gasket (22) is compressed to improve the heat insulating properties of the storage compartment, an energy saving property can improved; and in the second closed door mode in which the compressed state of the gasket (22) is loosened to reduce the door-opening force, the door can be opened with a small force.

Description

TECHNICAL FIELD

[0001] The present invention relates to a refrigerator having a configuration with which a heat insulating property of a storage compartment is improved.

BACKGROUND ART

[0002] Common refrigerators for home use are provided with gaskets made of resin materials to reduce leakage of cooled air through a gap between the housing and the door. As a refrigerator in which a heat insulating property is improved, there is proposed a refrigerator in which a gasket, and a protruding wall and a flange are used to doubly shield the leakage of cooled air through the gap between the housing and the door, for example, (for example, see PTL 1).

[0003] Fig. 10 and Fig. 11 are enlarged cross sectional views of a main part of a conventional refrigerator.

[0004] As shown in Fig. 10 and Fig. 11, doors 114, 115, and 116 each have outer face plate 124 made of a steel plate, inner face plate 125 which is made of resin and whose circumferential edge part is abutted on a rear flange of outer face plate 124, heat insulating member 126, and gasket 128 fixed in groove 127 formed in a circumferential edge part of inner face plate 125. The gaskets 128 are provided with a plurality of void parts 129 and further enclose magnet members 130 to improve contacts with front face flange 102a of outer case 102 shown in Fig. 10 and front face plate 131 of partition body 110 shown in Fig. 11. In addition to this configuration, to further improve the heat insulating property, protruding walls 132 are provided, as shown in Fig. 11, on partition body 110 on approximately the same plane as the surface of front face flange 103a of inner case 103 shown in Fig. 10. On the other hand, gaskets 128 are provided with hollow walls 133, which are abutted on front face flange 103a and a front face of protruding wall 132, on inner case 103 side and partition body 110 side, respectively. These hollow walls 133 and parts enclosing magnet members 130 doubly shield the leakage of cooled air from inside the refrigerator.

[0005] However, compared to the case of using heat insulation by multiple layers such as gasket 128, hollow wall 133, or the like, by reducing a heat exchange area between gasket 128 and external air by pressing gasket 128 against the housing (outer case 102, inner case 103) to compress gasket 128, the heat insulating property can be effectively improved. In addition, by pressing gasket 128 toward the housing (outer case 102, inner case 103), sealability is also improved, and leakage of cooled air can be reduced.

[0006] For this purpose, it is necessary to apply force to door 114 toward the housing (outer case 102, inner case 103), and it is common to provide a latch mechanism in which a spring, a magnet, or the like is used to pull in door 114 toward the housing (outer case 102, inner case 103).

[0007] However, if a pull-in force of the latch mechanism is too strong, a user needs to apply a large force to open the door, whereby children or aged people may not be able to open the door. As a result, the pull-in force of the latch mechanism needs to be designed slightly weak, and the heat insulating property has to be accordingly sacrificed. That is to say, the gasket cannot be sufficiently compressed, which means that there is room for further improving the heat insulating property. As described above, it is an object to achieve a balance between the further improvement of the heat insulating property and the improvement of door openability.

Citation List

Patent Literature

[0008] PTL 1: Japanese Patent No. 3,388,048

SUMMARY OF THE INVENTION

[0009] A refrigerator of the present invention includes: a housing constituted by a heat insulating wall; a storage compartment separated by a door which closes a storage opening of the housing; and a gasket which is provided on a circumferential edge of the door and brings the door into close contact with the housing. In addition, the door has a first closed door mode in which the gasket is pressed against the housing to be compressed, and a second closed door mode in which the compressed state of the gasket has been released from the first closed door mode.

[0010] With this arrangement, it is possible to improve the heat insulating property when the door is closed and at the same time to open the door without impairing operability when opening the door.

[0011] With a refrigerator of the present invention, because the heat insulating property of the storage compartment is improved in the first closed door mode when the door is closed, the power consumption can be reduced. In addition, because the compressed state of the gasket is released, when opening the door, in the second closed door mode, the door can be opened without impairing the operability, whereby the energy saving property is improved while the usability is maintained.

BRIEF DESCRIPTION OF DRAWINGS

[0012] 

Fig. 1 is a front view of a refrigerator of a first exemplary embodiment of the present invention.

Fig. 2 is a control block diagram of the refrigerator of the first exemplary embodiment of the present invention.

Fig. 3A is a planar sectional view in a normal closed door mode of a drawer storage compartment of the refrigerator of the first exemplary embodiment of the present invention.

Fig. 3B is a side sectional view of the drawer storage compartment of the refrigerator of the first exemplary embodiment of the present invention in the normal closed door mode.

Fig. 4A is a planar sectional view in a closed door mode in which the drawer storage compartment of the refrigerator of the first exemplary embodiment of the present invention is pulled in toward the housing.

Fig. 4B is a side sectional view in the closed door mode in which the drawer storage compartment of the refrigerator of the first exemplary embodiment of the present invention is pulled in toward the housing.

Fig. 5 is a flow chart of the refrigerator of the first exemplary embodiment of the present invention.

Fig. 6 is a control block diagram of a refrigerator of a second exemplary embodiment of the present invention.

Fig. 7A is a planar sectional view of a drawer storage compartment of the refrigerator of the second exemplary embodiment of the present invention in a normal closed door mode.

Fig. 7B is a side sectional view of the drawer storage compartment of the refrigerator of the second exemplary embodiment of the present invention in the normal closed door mode.

Fig. 8A is a planar sectional view in a closed door mode in which the drawer storage compartment of the second exemplary embodiment of the present invention is pushed out toward an open door direction.

Fig. 8B is a side sectional view in the closed door mode in which the drawer storage compartment of the second exemplary embodiment of the present invention is pushed out toward an open-door direction.

Fig. 9 is a flow chart of the refrigerator of the second exemplary embodiment of the present invention.

Fig. 10 is an enlarged sectional view of a main part of a conventional refrigerator.

Fig. 11 is an enlarged sectional view of a main part the conventional refrigerator.

DESCRIPTION OF EMBODIMENTS

[0013] Exemplary embodiments of the present invention will be described below with reference to the drawings. However, the exemplary embodiments do not limit the present invention.

<First exemplary embodiment>

[0014] A refrigerator of the first exemplary embodiment of the present invention will be described below with reference to the drawings.

[0015] Fig. 1 is a front view of the refrigerator of the first exemplary embodiment of the present invention, and Fig. 2 is a control block diagram of the refrigerator of the first exemplary embodiment of the present invention. Fig. 3A is a planar sectional view of a drawer storage compartment of the refrigerator of the first exemplary embodiment of the present invention in a normal closed door mode, and Fig. 3B is a side sectional view of the drawer storage compartment of the refrigerator of the first exemplary embodiment of the present invention in the normal closed door mode. Fig. 4A is a planar sectional view in a closed door mode in which the drawer storage compartment of the refrigerator of the first exemplary embodiment of the present invention is pulled in toward a housing, and Fig. 4B is a side sectional view in the closed door mode in which the drawer storage compartment of the refrigerator of the first exemplary embodiment of the present invention is pulled in toward the housing. Fig. 5 is a flow chart showing a control of a door of the refrigerator of the first exemplary embodiment of the present invention.

[0016] With reference to Fig. 1 to Fig. 4, a heat insulating case body as housing 11 is formed of an outer case in which a steel plate is mainly used, an inner case formed of resin such as ABS, and a heat insulating member injected between the outer case and the inner case.

[0017] The heat insulating case body as housing 11 is divided into a plurality of storage compartments in a heat insulating manner; on an uppermost part is provided refrigeration compartment 12; and under refrigeration compartment 12 are provided ice-making compartment 13 and selective compartment 14 in a side-by-side manner. Under ice-making compartment 13 and selective compartment 14 is provided freezing compartment 15, and on the lowermost part is disposed vegetable compartment 16. In front of each of the storage compartments (refrigeration compartment 12, ice-making compartment 13, selective compartment 14, freezing compartment 15, and vegetable compartment 16), a heat insulating door to separate the compartments from external air is provided in such a manner that an opening of each storage compartment is openable.

[0018] In the vicinity of a center of refrigeration compartment door 12a, which is a heat insulating double door, of refrigeration compartment 12, there is disposed operation unit 17 on which settings of inside temperatures for the storage compartments and settings of ice making and rapid cooling can be made, and detection result of the storage states and the operation conditions of the refrigerator can be displayed. Above this operation unit 17 is provided human detection sensor 18 to detect a motion of a surrounding human, and the possibility for the refrigerator to be used is estimated by operation controller 1 shown in Fig. 2. As human detection sensor 18, there is used an optical type sensor such as an infrared sensor or an ultrasonic sensor. Other than these sensors, there may be used a touch sensor which detects a touch of a human on the door or a door opening-and-closing detection sensor which detects the opening and closing of the door. An illuminance sensor may also be used to estimate that when it is dark in the surrounding area, the possibility for a human to be there is low, and that when it is bright in the surrounding area, the possibility for a human to be there is high. A combination of the above-described sensors may also be used for more accurate detection.

[0019] In a machine room (not shown) formed in a rear area and an uppermost part of refrigeration compartment 12, there are housed component parts for a freezing cycle such as compressor 30 and a dryer for water removal.

[0020] On a back surface of freezing compartment 15 there is provided a cooling compartment (not shown) for generating cooled air, and in the cooling compartment there are disposed a cooling device (not shown) and cooling fan 31 for distributing cooled air cooled by the cooling device to refrigeration compartment 12, selective compartment 14, ice-making compartment 13, vegetable compartment 16, and freezing compartment 15. In addition, in an air passage is disposed an air rate adjusting dumper 32 for adjusting the rate of air from cooling fan 31. Further, in order to defrost frost and ice built up on the cooling device and the surrounding area, there are configured a radiant heater (not shown), a drain pan (not shown), a drain tube evaporation tray (not shown), and the like.

[0021] The temperature for refrigeration compartment 12 is usually set at 1 °C to 5 °C with a nonfreezing temperature as a lower limit for refrigerating storage, and the temperature for vegetable compartment 16 on the lowermost part is set at 2 °C to 7 °C equal to or slightly higher than the temperature for refrigeration compartment 12. The temperature for freezing compartment 15 is set in a freezing temperature zone and is usually set at -22 °C to -15 °C for freezing storage, however, is sometimes set at lower temperatures of, for example, -30 °C or -25 °C for better freezing storage states.

[0022] In ice-making compartment 13, ice is made of water fed from a water storage tank in refrigeration compartment 12 by an automatic ice-making device provided on an upper part of the compartment, and the ice is stored in an ice storage container disposed on a lower part of the compartment.

[0023] The temperature for selective compartment 14 can be switched to a temperature zone having been preset between the refrigeration temperature zone and the freezing temperature zone in addition to the refrigeration temperature zone set at 1 °C to 5 °C, a vegetable storage temperature zone set at 2 °C to 7 °C, and the freezing temperature zone usually set at -22 °C to -15 °C. Selective compartment 14 is a storage compartment, which is provided alongside ice-making compartment 13 and is provided with an independent door, and is often provided with a drawer type door.

[0024] Note that in the present exemplary embodiment, selective compartment 14 is a storage compartment including a refrigeration temperature zone and a freezing temperature zone. However, the refrigeration temperature zone can be assigned to refrigeration compartment 12 and vegetable compartment 16, and the freezing temperature zone can be assigned to freezing compartment 15; thus, selective compartment 14 can be a storage compartment dedicated to switching the temperature only in the above-described temperature zone between the refrigeration temperature zone and the freezing temperature zone. Alternatively, with the growing demand for frozen foods in recent years, selective compartment 14 can be a storage compartment fixedly set at a specific temperature zone, for example, the freezing temperature zone.

[0025] On door 15a of freezing compartment 15, there is attached a storage case 20 held by frame 19. In addition, on a drawer rail part of door 15a, there is equipped latch mechanism 21a which pulls in door 15a toward housing 11 to surly close door 15a. Further, in order to prevent cooled air from leaking through the gap between door 15a and housing 11, there is provided gasket 22 made of resin material.

[0026] Because the gap dimension α between housing 11 and door 15a varies between refrigerators, depending on dimensional variation and assembly variation of the structural components, gasket 22 is made to have elasticity and have a size slightly larger than the gap dimension α. With this arrangement, gasket 22 is slightly compressed when door 15a is closed. If a pull-in force of latch mechanism 21a is made stronger to more strongly compress gasket 22, the housing 11 and gasket 22 are in closer contact with each other so that the heat insulating property of freezing compartment 15 are improved; however, the door-opening force needs to be accordingly strong, whereby a user not having a strong hand force such as aged people and children may not be able to open the door. To address this issue, the pull-in force of latch mechanism 21a is controlled so that door 15a can be opened with a slightly weak force, for example, less than 50 N, and there is room left for gasket 22 to be further compressed.

[0027] Actuator 23a is made up of motor 28a, a gear mechanism (not shown), and the like, and the driving force is transmitted to rotation axis 24a to rotationally move arm 25a. Instead of motor 28a, other power sources such as a solenoid can be used.

[0028] Frame 19 is provided with pull-in rod 26a, and arm 25a comes in contact with pull-in rod 26a when arm 25a rotationally moves. That is to say, the motion of arm 25a is transmitted to door 15a via pull-in rod 26a.

[0029] Operation of the refrigerator configured as described above will be described below with reference to Fig. 3A, Fig. 3B, Fig. 4A, Fig. 4B, and the flow chart of Fig. 5.

[0030] In the initial state, actuator 23a keeps arm 25a at a position shown in Fig. 3A and Fig. 3B, and this state is defined as a standard position of arm 25a. In this state, because arm 25a and pull-in rod 26a do not interfere with each other, door 15a can be freely opened and closed. Door 15a is subjected to the action of latch mechanism 21a pulling in toward housing 11; however, because the pull-in force of latch mechanism 21a is set at a predetermined value or less to control the door-opening force, there is room left for gasket 22 to be further compressed. This state shown in Fig. 3A and Fig. 3B is defined as a second closed door mode.

[0031] However, if a user is not in the vicinity of the refrigerator, there is no possibility for door 15a to be opened and closed; therefore, there is no need for controlling the door-opening force, whereby door 15a can be strongly pulled in toward housing 11 to sufficiently compress gasket 22 so as to improve a heat insulating property.

[0032] For this purpose, door opening-and-closing detector 2 shown in Fig. 2 detects that door 15a is in the closed door mode, and human detection sensor 18 detects whether no human is in the vicinity of the refrigerator. If no human is detected for a predetermined time or more (step S101; Y), it is determined that the refrigerator will not be used for a while, and actuator 23a is supplied with electricity to strongly pull in door 15a toward housing 11 (step S102). Although a pull-in force required at this time varies depending on the elasticity of the gasket, the friction of a drawer rail of door 15a, and the weight of foods in freezing compartment 15, and other factors, the gasket can be sufficiently compressed with a force of approximately 50 N to 300 N. This action is realized by a mechanism in which arm 25a is rotationally moved to be brought into contact with pull-in rod 26a as shown in Fig. 4A and Fig. 4B so that a force is applied to door 15a in the direction toward housing 11. By this operation, the gap ß between housing 11 and door 15a is made narrower than the gap α shown in Fig. 3A and Fig. 3B, and gasket 22 is thus compressed by 10% or more with respect to the original thickness. This state shown in Fig. 4A and Fig. 4B is defined as a first closed door mode.

[0033] In the state shown in Fig. 4A and Fig. 4B, actuator 23a, arm 25a, and pull-in rod 26a constitute a compression structure which brings gasket 22 in close contact with housing 11.

[0034] Gasket 22 can be further compressed by using a soft material and reducing a material thickness, and the contact area is thus reduced, the heat insulating property can be expected to be improved. At this time, the pull-in force required to compress gasket 22 of actuator 23a can be expected to be reduced.

[0035] A magnet is often built in gasket 22 to improve contact with housing 11. However, because in the present exemplary embodiment, the contact is already high due to the pull-in force of actuator 23a, there is no need for a magnet. This arrangement eliminates heat loss due to heat transfer through a magnet, and thus the heat insulating property can be further improved.

[0036] Note that, the cooler a cooled air is, the lower the cold air moves down; thus, the heat insulating property can be more effectively improved if gasket 22 is compressed on a lower part of door 15a. For this reason, in the present exemplary embodiment, actuator 23a is provided on a lower surface of freezing compartment 15 to pull mainly in the lower part of door 15a.

[0037] After gasket 22 is compressed and brought into sufficiently close contact with housing 11, supply of electricity to actuator 23a is stopped. However, since design is made such that a holding torque is generated by motor 28a and a gear mechanism in actuator 23a without supply of electricity, the pull-in state of Fig. 4A and Fig. 4B is held (step S103).

[0038] In this way, in the state that supply of electricity to actuator 23a is stopped, actuator 23a, arm 25a, and pull-in rod 26a constitute a compression holding structure which holds the compressed state of gasket 22 without supply of electricity.

[0039] Note that, a mechanism may be used in which a transmission mechanism from motor 28a to arm 25a is locked to hold the state of Fig. 4A and Fig. 4B without supply of electricity. For example, a mechanism can be used in which a spring mechanism or a second motor mechanism is interfered with a gear to lock.

[0040] When gasket 22 is in sufficiently close contact with housing 11, the heat insulating property of freezing compartment 15 is improved, whereby leakage of cooled air to outside can be reduced. Thus, electric power of a cooling system such as compressor 30 and cooling fan 31 can be reduced; and since actuator 23a is not supplied with electricity either, power consumption of the refrigerator can be reduced.

[0041] This state of improved a heat insulating property continues until a human comes in the vicinity of the refrigerator. If human detection sensor 18 detects a human to be present (step S104: Y), there is a possibility for door 15a to be opened and closed; therefore, arm 25a has to be quickly returned to the standard position shown in Fig. 3A and Fig. 3B so that the door can be opened with a weak force. At this time, actuator 23a makes arm 25a move in the direction opposite to that in step S102 to return arm 25a to the standard position (the second closed door mode) within the time (about 3 seconds) after the a human is detected and before door 15a is opened (step S105). This action from step S101 to step S105 is basic operation of the present exemplary embodiment.

[0042] In this way, in the state shown in Fig. 3A and Fig. 3B, actuator 23a, arm 25a, and pull-in rod 26a constitute a decompression structure which releases the compressed state of gasket 22.

[0043] If a human is detected to be present in step S101 (step S101: N), arm 25a holds the standard position of Fig. 3A and Fig. 3B. In this time, it is determined, by standard position detector 27a provided in actuator 23a, whether arm 25a is at the standard position (step S106). If arm 25a is determined to be at the standard position (step S106: Y), actuator 23a does not operate. However, if arm 25a is not at the standard position due to position shift or other reasons by any chance (step S106: N), an original point adjustment operation, which is operation of returning arm 25a to the standard position, is performed (step S107). By this alignment operation, a rotational error of arm 25a can be reduced, and it is preferable to perform the alignment operation also at the time of power-on and other timings.

[0044] As described above, in the present exemplary embodiment, when there is no possibility for a human to use the refrigerator, actuator 23a strongly pulls in door 15a to improve the heat insulating property. Alternatively, when there is a possibility for a human to use the refrigerator, the pull-in force of door 15a can reduced before the door is opened and closed, thereby reducing the door-opening force.

[0045] On the other hand, in the above-described configuration, even if a human comes in the vicinity of the refrigerator when arm 25a is in the state of Fig. 4A and Fig. 4B, for example, at a time of power failure, arm 25a cannot be returned to the standard position. That is to say, there may be a possibility that door 15a cannot be opened at a time of power failure. To address this issue, actuator 23a is designed such that when there is applied an external force slightly stronger than a force at the time of pulling in, arm 25a can be returned to the standard position. This mechanism is realized by, for example, using a clutch mechanism or a mechanism in which the mesh of the gears is releasable with a predetermined external force or more.

[0046] In this way, when a user performs door-opening operation of door 15a with a slightly strong force, the user can release the holding state even at a time of power failure and can use foods in freezing compartment 15. Alternatively, a mechanism may be provided in which arm 25a is returned to the standard position by manual lever operation in vegetable compartment 16 or from outside of housing 11 or by other operations.

[0047] In the description of the present exemplary embodiment, human detection sensor 18 is used to detect whether a human is not in the vicinity of the refrigerator; however, it is possible to use a touch sensor, a switch, or the like which detects a human's touch on the door.

[0048] In the present exemplary embodiment, the above description has been made on freezing compartment 15; however, the present system may be applied to the other storage compartments (refrigeration compartment 12, ice-making compartment 13, selective compartment 14, and vegetable compartment 16).

<Second exemplary embodiment>

[0049] A refrigerator of a second exemplary embodiment of the present invention will be described below with reference to the drawings. Note that, the same configurations as in the first exemplary embodiment of the present invention will be assigned the same reference marks and will not be described again.

[0050] Fig. 6 is a control block diagram of the refrigerator of the second exemplary embodiment of the present invention. Fig. 7A is a planar sectional view of a drawer storage compartment of the refrigerator of the second exemplary embodiment of the present invention in a normal closed door mode, and Fig. 7B is a side sectional view of the drawer storage compartment of the refrigerator of the second exemplary embodiment of the present invention in the normal closed door mode. Fig. 8A is a planar sectional view in a closed door mode in which the drawer storage compartment of the refrigerator of the second exemplary embodiment of the present invention is pushed out, and Fig. 8B is a side sectional view in the closed door mode in which the drawer storage compartment of the refrigerator of the second exemplary embodiment of the present invention is pushed out. Fig. 9 is a flow chart showing a control of a door of the refrigerator of the second exemplary embodiment of the present invention.

[0051] In a drawer rail part of door 15b is provided latch mechanism 21b which pulls in door 15b toward housing 11 to surely close door 15b. Further, in order to prevent cooled air from leaking through the gap between door 15b and housing 11, gasket 22 made of a resin material is provided.

[0052] Different from the first exemplary embodiment, a force with which latch mechanism 21b pulls in door 15b is set to slightly strong, for example, 50 N or more so that gasket 22 can be sufficiently compressed; thus, gasket 22 is in close contact with housing 11.

[0053] As described above, in the state shown in Fig. 7A and Fig. 7B, latch mechanism 21b constitutes a compression structure to bring gasket 22 into close contact with housing 11.

[0054] In addition, in the state shown in Fig. 7A and Fig. 7B, latch mechanism 21b also constitutes as a compression holding structure to hold the compressed state of gasket 22 without electric power.

[0055] In this state, a large door-opening force is required, and a user not having a strong hand force such as aged people and children may not be able to open the door. Therefore, when a human is in the vicinity of the refrigerator, actuator 23b applies a force in a door-opening direction so that door 15b can be opened even with a weak force.

[0056] Actuator 23b is made up of motor 28b, a gear mechanism (not shown), and the like, and the driving force is transmitted to rotation axis 24b to rotationally move arm 25b. Instead of motor 28b, other power sources such as a solenoid can be used.

[0057] Frame 19 is provided with push-out rod 26b, and arm 25b comes in contact with push out rod 26b when arm 25b rotationally moves. That is to say, the motion of arm 25b is transmitted to door 15b via push-out rod 26b.

[0058] Operation of the refrigerator configured as described above will be described below with reference to Fig. 7A, Fig. 7B, Fig. 8A, Fig. 8B, and the flow chart of Fig. 9.

[0059] In the initial state, actuator 23b keeps arm 25b at a position shown in Fig. 7A and Fig. 7B, and this state is defined as a standard position of arm 25b. At this time, door 15b is subjected to an action of being strongly pulled in toward housing 11 by latch mechanism 21b, and gasket 22 is sufficiently compressed, whereby the gap dimension between housing 11 and door 15b is narrowed to be β.

[0060] When a user is in the vicinity of the refrigerator, there is a possibility for door 15b to be opened and closed; therefore, there is a need for an action to reduce the door-opening force. For this purpose, door opening-and-closing detector 2 shown in Fig. 6 detects that door 15b is in a closed door mode, and human detection sensor 18 detects whether a human is in the vicinity of the refrigerator. If a human is detected (step S201: Y), it is determined that there is a possibility for door 15b to be opened, and actuator 23b is supplied with electricity to push out door 15b in the door-opening direction (step S202). At this time, a required push-out force varies depending on the elasticity of gasket 22, the friction of the drawer rail of door 15b, and the weight of foods in freezing compartment 15, and door 15b can be pushed out with a force of approximately 50N to 300N. This action is realized by a mechanism in which arm 25b is rotationally moved to be brought into contact with push-out shaft 26b as shown in Fig. 8A and Fig. 8B so that a force is applied to door 15b in the door-opening direction. By this operation, the gap α between housing 11 and door 15b is made wider than the gap β shown in Fig. 7A and Fig. 7B; thus, a pull-in force by latch mechanism 21b is reduced, and the thickness of gasket 22 returns to the original thickness.

[0061] As described above, in the state shown in Fig. 8A and Fig. 8B, actuator 23b, arm 25b, and push-out shaft 26b constitute a decompression structure which releases the compressed state of gasket 22.

[0062] Note that, when a part which pushes out door 15b is at the same level as the drawer rail of door 15b, the door tends to be pushed out with the minimum force. In the present exemplary embodiment, because the drawer rail is below door 15b, actuator 23b is provided on a lower surface of freezing compartment 15.

[0063] After the pull-in force of latch mechanism 21b is reduced, supply of electricity to actuator 23b is stopped. However, because design is made such that a holding torque is generated by motor 28b and a gear mechanism in actuator 23b without supply of electricity, the push-out state of Fig. 8A and Fig. 8B is held (step S203). Note that, a mechanism may be used in which a transmission mechanism from motor 28b to arm 25b is locked to hold the state of Fig. 8A and Fig. 8B without supply of electricity. For example, a mechanism can be used in which a spring mechanism or a second motor mechanism is interfered with a gear to lock.

[0064] When gasket 22 is being in sufficiently close contact with housing 11, the heat insulating property of freezing compartment 15 is improved, whereby leakage of cooled air to outside can be reduced. Thus, electric power of a cooling system including compressor 30, cooling fan 31, air rate adjusting dumper 32, and the like can be reduced, whereby power consumption of the refrigerator can be reduced. In addition, actuator 23b is also not supplied with electricity in the push-out state of Fig. 8A and Fig. 8B, the power consumption is not greater than usual.

[0065] The push-out state of Fig. 8A and Fig. 8B continues until the human disappears from the vicinity of the refrigerator. If human detection sensor 18 detects that no human is present (step S204: Y), because there is no possibility for door 15b to be opened, arm 25b needs to be returned to the standard position of Fig. 7A and Fig. 7B so that pull-in force of latch mechanism 21b improves the heat insulating property. At this time, actuator 23b makes arm 25b move in the direction opposite to that in step S202 to return arm 25b to the standard position (step S205). This action from step S201 to step S205 is basic operation of the present system.

[0066] If a human is not detected to be present in step S201 (step S201: N), arm 25b holds the standard position of Fig. 7A and Fig. 7B. At this time, standard position detector 27b provided in actuator 23b determines whether arm 25b is at the standard position (step S206). If arm 25b is determined to be at the standard position (step S206: Y), actuator 23b does not operate. However, arm 25b is not at the standard position due to position shift or other reasons by any chance (step S206: N), an operation for returning arm 25b to the standard position is performed (step S207). However, because a human is in the vicinity of the refrigerator just after power is supplied, it is preferably to rotationally move arm 25b to the position of Fig. 8A and Fig. 8B.

[0067] As describe above, in the present exemplary embodiment, when there is no possibility for a human to use the refrigerator, door 15b is strongly pulled in by latch mechanism 21b to improve the heat insulating property. Alternatively, when there is a possibility for a human to use the refrigerator, door 15b is pushed out by actuator 23b in the door-opening direction to reduce the door-opening force.

[0068] Door 15b is slightly pushed out in step S202; however, arm 25b can be largely rotationally moved to release door 15b when a user touches door 15b.

[0069] In the present exemplary embodiment, the above description has been made about freezing compartment 15; however, the present system may be applied to the other storage compartments (refrigeration compartment 12, ice-making compartment 13, selective compartment 14, and vegetable compartment 16).

[0070] As described above, the present invention includes: a housing formed of a heat insulating wall; a storage compartment separated by a door which closes a storage opening of the housing; and a gasket which is provided on a circumferential edge of the door and brings the door into close contact with the housing. In addition, the door has a first closed door mode in which the gasket is pressed toward the housing to be compressed, to improve heat insulating property of the storage compartment, and a second closed door mode in which the compressed state of the gasket is released from the first closed door mode.

[0071] With this arrangement, in the first closed door mode in which the gasket is compressed to improve the heat insulating property of the storage compartment, the energy saving property can be improved. In the second closed door mode in which the compressed state of the gasket is loosened to reduce the door-opening force, the door can be opened with a small force. As a result, the improvement of the heat insulating property and the door openability are both achieved at the same time.

[0072] Further, the present invention includes, in the first closed door mode: a compression structure which brings the gasket into close contact with the housing to improve the heat insulating property of the storage compartment; and a compression holding structure which holds the compressed state of the gasket without electric power, and the present invention includes, in the second closed door mode, a decompression structure which releases the compressed state of the gasket.

[0073] The above structures allow the first closed door mode and the second closed door mode to switchingly constitute each of the independent operations of the compression, the compression holding, and the release of compression; and the structures achieve both of the improvement of the heat insulating property and the improvement of the door openability while reducing the power required to the operation.

[0074] Further, the present invention includes a prediction unit which predicts the opening and closing of the door in advance, and when the prediction unit predicts that the door will not be opened and closed within a predetermined period of time, the first closed door mode is established, and when the prediction unit predicts that the door will be opened and closed within the predetermined period of time, the second closed door mode is established before the door is opened and closed.

[0075] With this arrangement, when there is no possibility for a human to open and close the door, the compressed state is surely established, whereby energy saving operation can be performed with no loss. Alternatively, when a human comes close and it is predicted that there is a possibility of a door opened and closed within a predetermined period of time, the compression can be loosened to increase the door openability, whereby the door can be opened with a weak force.

[0076] In the present invention, the compression structure, the compression holding structure, and the decompression structure are formed of an electric actuator using a motor or a solenoid as a driving source.

[0077] With this arrangement, it is possible for the door and the housing to be surely in close contact with each other with a strong force. In addition, the closed door modes can be changed by controlling the actuator; therefore, the system can be easily realized.

[0078] The present invention uses as the compression holding structure the retentive force of the electric actuator when power disconnected.

[0079] With this arrangement, any special mechanism for holding is not required, whereby the system can be realized by a simple configuration.

[0080] Alternatively, in the present invention, the compression holding structure is an electric lock mechanism which locks the driving source of the electric actuator or a transmission mechanism to an output unit when the gasket is brought into strongly close contact with the housing, and the compressed state of the gasket is thus held.

[0081] With this arrangement, since a mechanism dedicated to compression holding is used, the compressed state can be surely held with a strong force.

[0082] Alternatively, in the present invention, the compression holding structure is a lock mechanism which uses a spring and locks the driving source of the electric actuator or a transmission mechanism to an output unit when the gasket is brought into strongly close contact with the housing, and the compressed state of the gasket is thus held.

[0083] With this arrangement, a mechanism dedicated to compression holding is used, and in addition electric components such as a motor are not used; thus, the compressed state can be surely held with a simpler configuration.

[0084] Further, in the present invention, the decompression structure is configured to serve as the electric actuator and to perform reverse operation to compressing operation.

[0085] With this arrangement, a mechanism dedicated to releasing compression is not necessary, whereby a simple configuration can be realized.

[0086] Alternatively, in the present invention, the compression structure and the compression holding structure are configured to pull in the door toward the housing by a spring or a magnet.

[0087] With this arrangement, it is possible to realize compression of the gasket only by a simple modification in which a pull-in mechanism using a spring or a magnet provided in a conventional refrigerator is enhanced.

[0088] Further, in the present invention, the decompression structure is an electric actuator, for opening the door, using a motor or a solenoid as a driving source, and the decompression structure pushes out the door in the opening direction when the prediction unit predicts that the door will be opened and closed.

[0089] This arrangement can surely reduce the door-opening force. In addition, because the closed door modes can be changed by controlling the actuator, the system can be easily realized.

[0090] In the present invention, the prediction unit is a sensor which detects a human coming close to or moving in a predetermined area.

[0091] With this arrangement, it is possible to predict in advance the possibility for the door to be opened, whereby, just before the door is actually opened, the door is surely put in a state that the door openability is prioritized.

[0092] Alternatively, in the present invention, the prediction unit is a touch sensor or a switch which detects a human's touch on the door.

[0093] With this arrangement, because the door-opening force can be reduced only when the door is opened; thus, the compressed state is not released when a human is in the vicinity of the refrigerator but does not open the door.

[0094] In addition, in the present invention, the retentive force of the compression holding structure can be manually releasable with a predetermined force or more.

[0095] With this arrangement, the door can be opened even when the actuator does not operate at a time of power failure, failure of the actuator, or other cases.

INDUSTRIAL APPLICABILITY

[0096] A refrigerator of the present invention can be applied to or practiced in a door mechanism which needs to achieve a balance between the improvement of the heat insulating property of the door and the improvement of the door openability.

REFERENCE MARKS IN THE DRAWINGS

[0097] 

1

operation controller

2

door opening-and-closing detector

11

housing

12

refrigeration compartment

12a

refrigeration compartment door

13

ice-making compartment

14

selective compartment

15

freezing compartment

15a, 15b, 114, 115, 116

door

16

vegetable compartment

17

operation unit

18

human detection sensor

19

frame

20

storage case

21a, 21b

latch mechanism

22, 128

gasket

23a, 23b

actuator

24a, 24b

rotation axis

25a, 25b

arm

26a

pull-in rod

26b

push-out shaft

27a, 27b

standard position detector

28a, 28b

motor

102

outer case

102a, 103a

front face flange

103

inner case

110

partition body

124

outer face plate

125

inner face plate

126

heat insulating member

127

groove

129

void part

130

magnet member

131

front face plate

133

hollow wall

Claims

1. A refrigerator comprising:

a housing formed of a heat insulating wall;

a storage compartment separated by a door which closes a storage opening of the housing; and

a gasket which is provided on a circumferential edge of the door and brings the door into close contact with the housing,

wherein the door has:

a first closed door mode in which the gasket is pressed against the housing, and put into a compressed state to improve a heat insulating property of the storage compartment; and

a second closed door mode in which the compressed state of the gasket is released from the first closed door mode.

2. The refrigerator of claim 1, wherein
the first closed door mode includes:

a compression structure which brings the gasket into close contact with the housing to improve the heat insulating property of the storage compartment; and

a compression holding structure which holds the compressed state of the gasket without an electric power, and

the second closed door mode includes a decompression structure which releases the compressed state of the gasket.

3. The refrigerator of claim 2 further comprising a prediction structure which predicts opening and closing of the door, wherein, when the prediction structure predicts that the door will not be opened and closed within a predetermined period of time, the first closed door mode is established, and when the prediction structure predicts that the door will be opened and closed within the predetermined period of time, the second closed door mode is established before the door is opened and closed.

4. The refrigerator of claim 2, wherein the compression structure, the compression holding structure, and the decompression structure are formed of an electric actuator using a motor or a solenoid as a driving source.

5. The refrigerator of claim 4, wherein the compression holding structure uses a retentive force of the electric actuator when an electric power is disconnected.

6. The refrigerator of claim 4, wherein the compression holding structure is an electric lock mechanism which locks the driving source of the electric actuator or a transmission mechanism up to an output unit when the gasket is brought into strongly close contact with the housing, and the compression holding structure is configured to hold the compressed state of the gasket.

7. The refrigerator of claim 4, wherein the compression holding structure is a lock mechanism which uses a spring and locks the driving source of the electric actuator or a transmission mechanism up to an output unit when the gasket is brought into strongly close contact with the housing, and the compression holding structure is configured to hold the compressed state of the gasket.

8. The refrigerator of claim 4, wherein the decompression structure comprises a mechanism configured to serve as the electric actuator, and to perform reverse operation to compressing operation.

9. The refrigerator of claim 3, wherein the compression structure and the compression holding structure are configured to pull the door toward the housing by a spring or a magnet.

10. The refrigerator of claim 9, wherein the decompression structure is an electric actuator for opening the door by using a motor or a solenoid as a driving source, and the decompression structure pushes the door in an opening direction when the prediction unit predicts that the door will be opened and closed.

11. The refrigerator of claim 3, wherein the prediction unit is a sensor which detects a human coming close to or moving in a predetermined area.

12. The refrigerator of claim 3, wherein the prediction unit is a touch sensor or a switch which detects a touch of a human on the door.

13. The refrigerator of claim 2, wherein a retentive force of the compression holding structure is manually releasable with a predetermined force or more.

Drawing