JP2017181010A - Door opening/closing mechanism for refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a door opening/closing mechanism capable of reducing torque of a motor necessary for cancelling magnetization between a door and a housing.SOLUTION: A door opening/closing mechanism for a refrigerator includes: a motor M configured to output power for opening/closing the door; a power transmission mechanism 40 configured to transmit power of the motor M to a hinge by rotation of a plurality of drive gears 45; and an auxiliary mechanism 30 configured to generate auxiliary force for moving the door at a closed position toward an open direction. The door opening/closing mechanism is configured to generate the auxiliary force of the auxiliary mechanism 30 by power of the motor M, before transmitting the power of the motor M to the hinge Z through the power transmission mechanism 40.SELECTED DRAWING: Figure 34

Description

  The present invention relates to a refrigerator door opening / closing mechanism used for opening / closing a refrigerator door.

  As a device for automatically opening a refrigerator door, as shown in Patent Document 1, when a switch is operated with the door closed, a cam provided on the housing side is rotated by the driving force of the motor. However, there is a structure that protrudes toward the door and hits the door so that the door can be automatically opened.

  By the way, as a door opening / closing mechanism that not only automatically opens but also automatically closes, a plurality of gears are interposed between the motor output shaft and the door hinge, and the rotation of these gears causes the motor to rotate. It is possible to transmit power to the door and open and close the door.

  However, in the configuration described above, if a plurality of gears are engaged when opening the door in the closed position, the torque required to demagnetize the door and the case increases, and the size of the motor is reduced accordingly. Must be bigger.

JP 2002-257466 A

  Accordingly, the present invention is to solve the problem, and provides a door opening / closing mechanism for a refrigerator that can reduce the torque of a motor necessary to demagnetize the door and the casing. Is the main issue.

  That is, the refrigerator door opening and closing mechanism according to the present invention is in a closed position, a motor that outputs power for opening and closing the door, a power transmission mechanism that transmits the power of the motor to the hinges by rotation of a plurality of gears. An auxiliary mechanism for generating an auxiliary force for moving the door in the opening direction, and before the power of the motor is transmitted to the hinge via the power transmission mechanism, the auxiliary mechanism is driven by the power of the motor. Further, the auxiliary force is generated.

  In such a refrigerator door opening / closing mechanism, the door in the closed position is moved in the opening direction by the auxiliary force in a state where the motor power is not transmitted to the hinge, so that the door and the case are not magnetized. Therefore, the motor torque required can be reduced, and the motor can be reduced in size.

It is preferable to further include a power transmission state transition mechanism that changes between a power transmission state in which the power of the motor is transmitted to the hinge and a power non-transmission state in which the power of the motor is not transmitted to the hinge.
By using such a mechanism, the power transmission state can be changed mechanically without using an electrical connection such as a switching element.

  As a specific embodiment, the plurality of drive gears are connected to a door side gear that rotates in conjunction with opening and closing of the door, a motor side gear that rotates in conjunction with the motor, and the motor side gear. A center gear and a pair of idler gears that mesh with the center gear and maintain a predetermined relative position, and the power transmission state transition mechanism is interlocked with forward rotation or reverse rotation of the center gear. And a configuration having a swing mechanism that turns together with the pair of idle gears around the rotation axis of the center gear.

  As a specific operation, as the pair of idler gears rotate with the swing mechanism, one idler gear meshes with the door-side gear and moves the door in the opening direction. , Between the reverse rotation power transmission position where the other idle gear meshes with the door side gear and moves the door in the closing direction, and the power non-transmission position where none of the pair of idle gears mesh with the door side gear It is conceivable to move the

With the configuration described above, the pair of idle gears are moved between the power transmission position and the power non-transmission position by moving the pair of idle gears along a plane perpendicular to the rotation axis of the center gear by the swing mechanism. Since it can be moved, a clutch mechanism for moving the gear in the height direction is unnecessary, and the power transmission mechanism can be made compact in the height direction.
On the other hand, according to the power transmission mechanism according to the present invention described above, since the pair of idle gears move in conjunction with the rotation of the center gear, the pair of idle gears can be moved by the power of the motor. A dedicated actuator for switching between the non-transmission state can be eliminated.

Here, the principle of the pair of idle gears moving in conjunction with the rotation of the center gear will be described.
When the center gear is rotated by the power of the motor, a tangential force is applied to each of the idle gears through a portion engaged with the center gear. Due to this tangential force, a torque is generated in the pair of idler gears so that the pair of idler gears pivots around the center gear, so that the pair of idler gears move along a plane perpendicular to the rotation axis of the center gear. Become.

  Therefore, when moving the door in the closed position in the opening direction, in order to prevent the idle gear from meshing with the door side gear before the door and the case are demagnetized by the auxiliary force, the door for the refrigerator is used. It is preferable that the opening / closing mechanism further includes a power non-transmission state holding mechanism that regulates the swing of the swing mechanism and maintains the power non-transmission state without engaging each of the idle gears with the door-side gear. .

  As a specific embodiment, the power non-transmission state holding mechanism is provided on the mounting member and rotates with the mounting member, and the pair of idler gears are connected to the positive gear as the mounting member rotates. And a contacted portion for restricting the swinging mechanism of the swing mechanism by contacting the contact portion before the pair of idle gears reach the positive rotational power transmission position. The structure which is doing is mentioned.

The swing mechanism is attached to the floating gears, and is interposed between a mounting member that rotates around a rotation shaft of the center gear, and between the mounting member and the floating gears, and the rotation of each floating gear. It is preferable to have a rotational load member that applies a load to the motor.
If this is the case, the rotation load member makes it difficult for each idle gear to rotate, so that the torque generated in the pair of idle gears by the rotation of the center gear increases, and the pair of idle gears can be easily moved along the plane. Can do.

  As a specific embodiment of the auxiliary mechanism, a slide member that is provided at the upper portion of the door and is slidable in conjunction with rotation of the drive gear, and a predetermined rotation axis around the slide movement of the slide member And an auxiliary force applying member that contacts the housing by rotating around the rotation axis and applies the auxiliary force to the door.

  In order to generate the auxiliary force by transmitting the power of the motor to the auxiliary mechanism, the power in the rotational direction of the drive gear is moved between the auxiliary mechanism and the power transmission mechanism to move the auxiliary mechanism. It is preferable to provide a power conversion mechanism that converts power.

As a specific embodiment of the power conversion mechanism, when the motor rotates in the reverse direction and moves the door in the closing direction, the motor rotates forward without transmitting the power of the motor to the auxiliary mechanism. And when moving the said door to an opening direction, the structure provided with the ratchet mechanism which transmits the motive power of the said motor to the said auxiliary mechanism is mentioned.
In such a configuration, since the ratchet mechanism is used, when the door in the closed position is moved in the opening direction, an auxiliary force is generated while the door is moved in the closing direction. The movement of the door can be prevented from being hindered by the power conversion mechanism.

  As a specific embodiment of the ratchet mechanism, the ratchet mechanism includes a ratchet attached to the slide member, and a pressing portion that rotates in conjunction with the drive gear. When the motor rotates in the forward direction, the pressing portion When the slide member slides by contacting and pressing the ratchet and the motor rotates in the reverse direction, the ratchet escapes when the pressing portion comes into contact, and the slide member slides. The structure which does not move is mentioned.

When the ratchet has the abutted portion described above and the motor rotates forward in a state where the door is in the closed position, the abutting portion abuts on the abutted portion and the swing mechanism It is preferable that the turning is restricted, and then the pressing member presses the ratchet so that the sliding member slides and the door moves in the opening direction by the auxiliary force.
If this is the case, the above-described ratchet mechanism can be used as a configuration for generating an auxiliary force before the motor power is transmitted to the hinge, and it can be worn in a power non-transmission state without complicating the configuration. The magnet can be removed.

When the door is moved in the opening direction, if the slide member constituting the auxiliary mechanism is visible to the user, the appearance is poor.
Therefore, the auxiliary mechanism has a pull-back member that pulls back the slide member moved by the pressing portion pressing the ratchet, and when the ratchet is pulled back by the pull-back member, The pressed portion is pressed by the contact portion, and the contact portion presses the pressed surface, so that the ratchet moves in a direction away from the press portion, and then the press portion is It is preferable to rotate without interfering with the ratchet.
With such a configuration, the slide member can be returned to the original state after removing the magnetization of the door and the casing, and the pressing portion rotates without interfering with the returned slide portion. The slide member can be hidden from the user, and the appearance can be improved.

  The refrigerator door opening and closing mechanism according to the present invention is for opening and closing a refrigerator door, and supports a motor, a plurality of drive gears rotating in conjunction with the motor, and the door rotatably. A non-tooth gear that is attached to the hinge shaft of the hinge and rotates about the hinge shaft, and a contact position that contacts the drive gear and the drive gear in conjunction with the opening and closing movement of the door. And a non-contact gear rotation mechanism that rotates between the non-contact position and a non-contact position, and an auxiliary mechanism that generates an auxiliary force to move the door in the closed position in the opening direction, By the mechanism, when the door is in the closed position, the toothless gear is held in the non-contact position, and when the door in the closed position is moved in the opening direction by the auxiliary force, in conjunction with this movement, Said toothless gear Is characterized in that the rotating movement to the contact position from the non-contact position.

In the refrigerator door opening / closing mechanism configured as described above, when the auxiliary mechanism generates the auxiliary force, the missing tooth gear rotating mechanism holds the missing tooth gear at the non-contact position. Thus, the door and the case can be demagnetized in a state where the toothless gear is not meshed with the gear and the torque required to demagnetize can be reduced.
In addition, when the door in the closed position moves in the opening direction, the missing tooth gear rotation mechanism rotates the missing tooth gear from the non-contact position to the contact position. Therefore, the drive gear and the missing gear can be reliably meshed with each other. Accordingly, it is possible to prevent problems that may be caused by manually opening the door and complication of control, as compared with a configuration that uses missing teeth as a drive gear, and provide a more practical refrigerator door opening / closing mechanism. be able to.

  As an embodiment in which the effect of the present invention is more remarkably exhibited, there is a configuration in which the drive gear meshing with the missing tooth gear has teeth on the entire circumference.

By the way, when the motor is provided in the upper part of the housing, in order to transmit the power of the motor to the door, for example, a link member that spans from the housing side to the door side is provided, and the appearance of the refrigerator deteriorates. The problem arises. Further, when the link member is used, there is a risk that the user may pinch his / her hand on the link member.
Therefore, in order to solve such a problem, it is preferable that the motor is provided on an upper portion of the door.

  As a specific embodiment of the toothless gear rotation mechanism, a toothless gear biasing member that biases the toothless gear from the non-contact position toward the contact position, and a rotation around a rotation axis are provided. And a rotation member that is pressed against the missing tooth gear by rotating around the rotation shaft and rotates the missing tooth gear from the contact position to the non-contact position.

  As another specific embodiment of the toothless gear rotating mechanism, a contact position that is connected to the toothless gear and is in contact with a contacted part fixed to the housing side, and the contacted part A link member that moves by magnetic force between a separation position and a separation position that is separated from the door, and is provided on the door side, and contacts the link member in a state where the door is in the closed position to restrict the movement of the link member. A regulating member, and when the door is in the closed position, the regulating member keeps the link member at one of the contact position or the separated position, and the door moves in the opening direction by the auxiliary force. The regulating member moves in a direction away from the link member, the link member moves to the other of the contact position or the separation position by a magnetic force, and the toothless gear moves from the non-contact position to the contact position. Configured to move location and the like.

  In order to use magnetic force with a simple configuration, the contacted portion is a hinge plate attached to the housing, and the link member contacts the hinge plate in the state of the contact position. It has a magnet, It is preferable that the said partial gear moves from the said non-contact position to the said contact position when the said link member moves from the said separation | spacing position to the said contact position.

  The drive gear includes a door-side gear that rotates in conjunction with opening and closing of the door, a motor-side gear that rotates in conjunction with the motor, a center gear connected to the motor-side gear, and the center gear And a pair of idler gears that maintain a predetermined relative position together with the pair of idler gears about the rotation axis of the center gear in conjunction with forward rotation or reverse rotation of the center gear. The swing mechanism further includes a swing mechanism, and as the swing mechanism swings, the pair of idle gears has a positive rotational power transmission position where one idle gear meshes with the door side gear, and the other idle gear has the idle gear. A configuration in which the counter-rotating power transmission position that meshes with the door-side gear and the power non-transmission position where none of the pair of idle gears mesh with the door-side gear is preferable.

In such a refrigerator door opening / closing mechanism, the pair of idler gears are moved along the plane perpendicular to the rotation axis of the center gear by the swing mechanism, so that the pair of idler gears are transmitted to the power transmission position and the power non-transmission. Since it can be moved between positions, a clutch mechanism for moving the gear in the height direction is unnecessary, and the power transmission mechanism can be made compact in the height direction.
Further, according to the power transmission mechanism according to the present invention described above, since the pair of idle gears move in conjunction with the rotation of the center gear, the pair of idle gears can be moved by the power of the motor. A dedicated actuator for switching between the non-transmission state is not required.

The principle of the pair of idle gears moving in conjunction with the rotation of the center gear is as described above.
Therefore, the refrigerator door opening / closing mechanism restricts the movement of the pair of idle gears by the swing mechanism in order to keep the pair of idle gears at positions where they do not mesh with the door side gear. It is preferable to further include a power non-transmission state holding mechanism that makes a power non-transmission state in which none of the gears meshes with the door side gear.

As a specific embodiment, the swing mechanism includes an attachment member to which the idle gear is attached and which rotates about a rotation shaft of the motor side gear, and the power non-transmission state holding mechanism is the attachment mechanism. An idler gear biasing member for biasing the member to an intermediate position where the pair of idler gears are maintained in the power non-transmission position; and when the motor stops, the idler gear biasing member holds the mounting member When the pair of idler gears are biased to an intermediate position and moved to the power non-transmission position and the motor is driven, the pair of idler gears rotate against the biasing force of the idler gear biasing member, It is preferable that the pair of idle gears move to a forward rotation power transmission position or a reverse rotation power transmission position.
With the power non-transmission state holding mechanism configured as described above, the power non-transmission state can be held with a lightweight and inexpensive configuration.
On the other hand, when switching from the power non-transmission state to the power transmission state, when one or the other idler gear meshes with the door-side gear, the idler gear receives from the center gear and the door-side gear via the meshed portion. , A tangential force is applied. For this reason, when the power non-transmission state is switched to the power transmission state, the torque applied to the idle gear increases, and this torque resists the urging force of the idle gear urging member and the power transmission state is maintained.

It is preferable that the swing mechanism includes a rotation load member that is interposed between the attachment member and the idle gear and that applies a load to the rotation of each idle gear.
If this is the case, the rotation load member makes it difficult for each idle gear to rotate, so that the torque generated in the pair of idle gears by the rotation of the center gear increases, and the pair of idle gears can be easily moved along the plane. Can do.

  In order for one or the other idle gear to mesh with the door-side gear reliably by moving the pair of idle gears around the center gear, the door-side gear and the idle gear engaged with the door-side gear; The angle formed by the center gear is preferably 90 degrees or more and 130 degrees or less.

  As a specific embodiment of the auxiliary mechanism, the auxiliary mechanism is provided from one end side to the other end side in the upper part of the door, and a slide member that can slide in conjunction with rotation of the drive gear; An auxiliary force applying member that is provided so as to be rotatable around a predetermined rotation axis in conjunction with the slide movement of the slide member, and that contacts the housing by rotating around the rotation axis and applies the auxiliary force to the door. The structure which has these.

Here, some recent refrigerators are configured to open the door large (for example, 160 °) in consideration of maintainability and the like.
In such a refrigerator, when the above-mentioned missing gear is provided on the hinge shaft, the appearance of the missing gear is inferior when the teeth of the missing gear are visible when the door is opened wide. The area where the teeth are provided is limited (for example, up to the 130 ° position).
However, in such a configuration, when the door moves in the opening direction with the drive gear meshing with the missing gear, for example, when the door is stored in a large amount, the door opens greatly due to inertia, and the drive gear moves away from the missing gear. It may come off. Then, there arises a problem that the door cannot be closed automatically after the engagement is released.

  Therefore, the refrigerator door opening and closing mechanism according to the present invention is disengaged when the drive gear meshed with the missing gear disengages from the missing gear due to movement of the door in the opening direction. A return mechanism is further provided for moving the door in the closing direction so that the drive gear meshes with the toothless gear again.

If it is comprised in this way, since a return mechanism will mesh | engage the drive gear which mesh | engaged again with the missing gear, after a mesh | engagement, it will be able to open and close a door automatically again.
As a result, for example, even when the user opens the door when the storage is taken in or out, there is a large amount of storage of the door while ensuring the design so that the teeth of the missing gear do not protrude from the product exterior surface Even if the door opens more than necessary, the door can be automatically closed by meshing the drive gear with the missing gear.

  As a specific embodiment of the return mechanism, it comprises a flexible member having elasticity and a contact member that contacts and bends the flexible member, and one of the flexible member and the contact member is integrated with the door. And the other is fixed, the movement of the door in the opening direction causes the bending member and the contact member to come into contact with each other and the bending member bends, and the restoring force causes the door to close. Are configured to be moved.

The bending member is drawn in accordance with a tangent line that is in contact with the rotation locus of the contact point of the bending member and the contact member and passes through the rotation center of the bending member, and a degree of bending of the bending member that is predetermined around the bending member. It is preferable that the angle formed by the imaginary circle and the straight line passing through the intersection of the tangent line is 30 degrees or more and 60 degrees or less.
If it is such a structure, if the bending member is contacting the contact surface, the restoring force of a bending member can be decomposed | disassembled into the rotational force of a door. In other words, since the door can be rotated in the closing direction by the restoring force of the deflecting member after the deflecting member starts to contact the contact surface, it is not necessary to generate the restoring force instantaneously. Accordingly, for example, a cam attached to the hinge shaft as the contact member can be used without increasing the return mechanism, and the contact member or the like can be prevented from being exposed.

  In order not to deteriorate the appearance, one of the flexible member or the contact member is attached to the lower side of the door, and the other is fixed to the lower side of the hinge shaft or the lower side of the housing. It is preferable.

Here, in the refrigerator door control device configured to automatically open and close the door, conventionally, the applied voltage of the motor is controlled to be a predetermined value in order to control the moving speed of the door to a desired speed. It was like that.
However, in the control method described above, even if a voltage of the same magnitude is applied to the motor, the load on the motor varies depending on the amount of food stored in the door. The desired speed cannot be controlled.

  Under these circumstances, the inventor of the present application solves the problem of controlling the movement of the door with high accuracy and uniformity as compared with the conventional case, and the counter electromotive voltage generated when the motor is rotated is inversely proportional to the moving speed of the door. Focused on doing.

  That is, the refrigerator door opening and closing mechanism according to the present invention further includes a refrigerator door control device that controls a motor for moving the refrigerator door and automatically moves the door, and the refrigerator door control device includes: An induced voltage detector that detects an induced voltage that is generated when the motor is rotating, and a detection value that is detected by the induced voltage detector is a target value that is predetermined according to the opening angle of the door. As described above, an applied voltage control unit for controlling the applied voltage of the motor is provided.

  In such a case, since the induced voltage of the motor is controlled to be a target value of the induced voltage that is predetermined according to the opening angle of the door, the moving speed of the door is set according to the target value. The speed can be set, and the desired speed can be controlled regardless of the storage amount of the door.

  As a more specific embodiment, the moving range of the door is divided into a plurality of continuous divided ranges, and the target value is determined for each divided range.

Here, in order to detect the opening angle of the door, it is necessary to set a state where the opening angle is zero. Specifically, for example, when the motor starts to move or when the user presses the door open switch A mode in which the door is opened and the angle is zero is conceivable.
However, the time from when the motor starts to move or when the user presses the switch until the door starts to open is not always constant, and in the above-described aspect, the detected opening angle varies. End up.

Therefore, in order to accurately detect the opening angle of the door, when the applied voltage for moving the door in the opening direction becomes a predetermined threshold value when the door is closed, the opening is performed. It is preferable to further include a zero setting unit that sets the angle to zero and an opening angle detection unit that detects the opening angle from the opening angle zero set by the zero setting unit.
With such a configuration, the opening angle is set to zero when the applied voltage reaches a predetermined threshold value, so even if the amount of movement occurs after the motor starts to move and the door starts to open, it can be detected. The opening angle does not vary, and the opening angle can be detected with high accuracy.

  As an embodiment for detecting the opening angle of the door with a simple and inexpensive configuration, an encoder or a rotary switch is provided in a drive gear that is interposed between the motor and the door and rotates in conjunction with the motor. And a configuration in which the opening angle detection unit detects the opening angle based on an output from the encoder or the rotary switch.

  According to the present invention configured as described above, it is possible to reduce the motor torque by reducing the torque of the motor necessary for demagnetizing the door and the casing.

The figure which shows typically the structure of the refrigerator in 1st Embodiment. The figure which looked at the door opening and closing mechanism for refrigerators of a 1st embodiment from the upper part. The figure which looked at the door opening / closing mechanism for refrigerators of 1st Embodiment from the downward direction. The figure which shows typically the power transmission state and power non-transmission state of 1st Embodiment. The figure which shows typically the swing mechanism of 1st Embodiment. The figure which shows typically the power conversion mechanism of 1st Embodiment. The figure which shows typically the missing-tooth gear rotation mechanism of 1st Embodiment. The figure which shows typically the return mechanism of 1st Embodiment. The figure explaining the motion of the return mechanism of 1st Embodiment. The figure explaining the design method of the contact surface of a 1st embodiment. The figure explaining the design method of the contact surface of a 1st embodiment. The circuit diagram which shows typically the door control apparatus for refrigerators of 1st Embodiment. The functional block diagram which shows the function of the door control apparatus for refrigerators of 1st Embodiment. The figure which shows typically the missing-tooth gear rotation mechanism in the modification of 1st Embodiment. The figure explaining operation | movement of the missing-tooth gear rotation mechanism in the modification of 1st Embodiment. The figure which shows typically the missing-tooth gear rotation mechanism of 2nd Embodiment. The figure explaining operation | movement of the missing-tooth gear rotation mechanism of 2nd Embodiment. The figure which shows typically the missing-tooth gear rotation mechanism in the modification of 2nd Embodiment. The figure which shows typically the swing mechanism of 3rd Embodiment. The figure which shows typically the swing mechanism of 3rd Embodiment. The figure which shows typically the structure of the power non-transmission state holding mechanism of 3rd Embodiment. The figure which shows typically the structure of the refrigerator of 4th Embodiment. The figure which shows typically the structure of the door opening / closing mechanism for refrigerators of 4th Embodiment. The figure which shows typically the power transmission state of 4th Embodiment. The figure which shows typically the power transmission mechanism of 4th Embodiment. The figure which shows typically the swing mechanism of 4th Embodiment. The figure which shows typically the power non-transmission state of 4th Embodiment. The figure which shows typically the power non-transmission state holding mechanism of 4th Embodiment. The figure which shows typically the link mechanism of 4th Embodiment. The figure which shows the auxiliary mechanism of 4th Embodiment typically. The functional block diagram which shows the function of the control part of 4th Embodiment. The electric circuit diagram which shows the control circuit for controlling the motor of 4th Embodiment. The figure which looked at the door opening and shutting mechanism for refrigerators of 5th Embodiment from upper direction. The figure which looked at the door opening / closing mechanism for refrigerators of 5th Embodiment from the downward direction. The figure which shows typically the power transmission state transition mechanism of 5th Embodiment. The figure which shows typically the power transmission state transition mechanism of 5th Embodiment. The figure which shows typically the power non-transmission state holding mechanism and power conversion mechanism of 5th Embodiment. The figure which shows the ratchet of 5th Embodiment typically. The figure explaining operation | movement of the ratchet of 5th Embodiment. The figure explaining operation | movement in the case of moving the door of 5th Embodiment to an opening direction. The figure explaining operation | movement in the case of moving the door of 5th Embodiment to an opening direction. The figure explaining operation | movement in the case of moving the door of 5th Embodiment to a close direction. The figure which shows the ratchet of 5th Embodiment typically. The figure explaining operation | movement of the ratchet of 5th Embodiment. The figure which looked at the door opening / closing mechanism for refrigerators in the modification of 5th Embodiment from the bottom.

<First Embodiment>
A first embodiment of a refrigerator door opening / closing mechanism 100 according to the present invention will be described below with reference to the drawings.

  First, the refrigerator R according to the present embodiment will be described.

  As shown in FIG. 1, the refrigerator R includes a housing H whose front surface is open and left and right doors D provided in the opening of the housing H, and each door D rotates about a hinge axis Z of a hinge. It is supported as possible.

The refrigerator door opening / closing mechanism 100 is for independently opening and closing each door D of the refrigerator R described above, and is provided in each of the upper portions of the left and right doors D here.
In the present embodiment, each refrigerator door opening / closing mechanism 100 has a bilaterally symmetrical configuration, and the refrigerator door opening / closing mechanism 100 for opening / closing the right door D in FIG. 1 will be described as a representative.

The refrigerator door opening / closing mechanism 100 opens the casing C provided on the upper surface of the door D, the drive mechanism 10 accommodated in the casing C, and the door D in the closed position, as shown in FIGS. And an auxiliary mechanism 30 for assisting the time.
Each configuration will be described below.

<Casing>
In order to prevent the appearance of the refrigerator R from being deteriorated, the casing C accommodates almost all of the drive mechanism 10 and the auxiliary mechanism 30 as shown in FIG. It has a long shape provided over the other end side.

<Drive mechanism>
The drive mechanism 10 outputs power for opening and closing the door D and transmits the power to the door D.
Specifically, as shown in FIGS. 2 and 3, this has a motor M and a power transmission mechanism 40 that transmits the power of the motor M to the door D via the hinge shaft Z.
2 is a view of the drive mechanism 10 as viewed from above, and FIG. 3 is a view of the drive mechanism 10 as viewed from below.

The motor M is provided in the upper part of the door D and is accommodated in the casing C, and receives a control signal from a control unit (not shown) and rotates forward or backward.
In this embodiment, the motor M is configured to open and close the door D based on a predetermined speed pattern based on a control signal from the control unit.

The power transmission mechanism 40 is interposed between the motor M and the hinge shaft Z, and is attached to the hinge shaft Z and a plurality of drive gears 45 that rotate in conjunction with the motor M, as shown in FIG. And a missing tooth gear 46.
The plurality of drive gears 45 have teeth on the entire circumference.

  Here, the power transmission mechanism 40 of the present embodiment has a power transmission state in which the power of the motor M is transmitted to the hinge shaft Z and the power is hinged so that the opening and closing of the door D can be switched between automatic and manual. It is configured to switch to a power non-transmission state that is not transmitted to the shaft Z.

  More specifically, as shown in FIGS. 2 to 4, the power transmission mechanism 40 includes a motor side gear 41 that rotates in conjunction with the motor M as a part of the plurality of drive gears 45, and a door. A door-side gear 42 that rotates in conjunction with opening and closing of D, a center gear 43 connected to the motor-side gear 41, and a pair of idle gears 44 that mesh with the center gear 43 (hereinafter referred to as one An idle gear 44a and the other idle gear 44b).

In the present embodiment, a plurality of motor side gears 41 and door side gears 42 are connected in series.
Of these motor side gears 41, the motor side gear 41 located closest to the motor side is connected to the rotation shaft of the motor M, and the motor side gear 41 located closest to the door side is connected to the rotation shaft of the center gear 43. Has been.
Of the plurality of door-side gears 42, the door-side gear 42 positioned closest to the motor side meshes with the idle gear 44, and the door-side gear 42 positioned closest to the door side meshes with the toothless gear 46.

  As shown in FIGS. 4 and 5, the pair of idle gears 44 that mesh with the center gear 43 are arranged so as to sandwich a straight line that connects the rotation shaft of the center gear 43 and the rotation shaft of the door side gear 42 closest to the motor. It rotates in conjunction with the center gear 43.

  As shown in FIGS. 4 and 5, the power transmission mechanism 40 according to the present embodiment rotates the center gear 43 to rotate the pair of idle gears 44 around the center gear 43. And a power non-transmission state holding mechanism 60 that maintains a power non-transmission state in which none of the idle gears 44 meshes with the door-side gear 42. .

  As shown in FIG. 4, the swing mechanism 50 includes a pair of idle gears 44, a positive rotational power transmission position (FIG. 4a) where one idle gear 44a meshes with the door side gear 42, and the other idle gear 44b. It is moved between the reverse rotation power transmission position (FIG. 4c) meshed with the door side gear 42 and the power non-transmission position (FIG. 4b) where none of the pair of idle gears 44 meshes with the door side gear 42.

  The swing mechanism 50 according to the present embodiment turns a pair of idle gears 44 around the rotation axis of the center gear 43 along the rotation direction of the center gear 43, whereby one idle gear 44 a becomes the door side gear 42. The other idler gear 44b is separated from the door side gear 42, or the other idler gear 44b is engaged with the door side gear 42 and the one idler gear 44a is separated from the door side gear 42. .

  More specifically, as shown in FIG. 4 (a), when the center gear 43 rotates forward in conjunction with the rotation of the motor M (in this case, counterclockwise when viewed from above), the pair of idle gears 44 is centered. Turning around the rotation axis of the gear 43 as viewed from above, it turns counterclockwise, and one free gear 44 a meshes with the door side gear 42. Thereby, the door opening / closing mechanism 100 for refrigerators of this embodiment will be in the automatic opening mode which the door D opens automatically with the motive power of the motor M. FIG.

  On the other hand, as shown in FIG. 4C, when the center gear 43 rotates in reverse in conjunction with the rotation of the motor M (in this case, clockwise when viewed from above), the pair of idle gears 44 rotate the center gear 43. The other idler gear 44b meshes with the door-side gear 42 by turning clockwise around the shaft as viewed from above. Thereby, the door opening / closing mechanism 100 for refrigerators of this embodiment will be in the automatic closing mode which the door D closes automatically with the motive power of the motor M. FIG.

  In the automatic opening mode and the automatic closing mode described above, the door-side gear 42, one or the other idler gear 44 meshing with the door-side gear 42, and the center gear 43 have an angle α of 90 degrees or more and In this embodiment, the angle α is designed to be not less than 110 degrees and not more than 120 degrees.

Next, a specific configuration of the swing mechanism 50 will be described.
As shown in FIG. 5, the swing mechanism 50 rotates around the rotation shaft of the center gear 43 and is interposed between the attachment member 51 to which the idle gear is attached, and the attachment member 51 and the idle gear 44. In addition, a rotation load member 52 that applies a load to the rotation of each idle gear 44 is provided.

The mounting member 51 includes a flat plate member 511 on which both the center gear 43 and the pair of idle gears 44 are provided, and a pair of idle gear mounting shafts 512 that stand up from the flat plate member 511 and to which the idle gear 44 is attached. Yes.
The mounting member 51 is formed with a through hole (not shown) through which the center gear mounting shaft 7 to which the center gear 43 is mounted passes. By passing the attachment member 51 through the center gear attachment shaft 7 through the through hole, the attachment member 51 can rotate around the center gear attachment shaft 7.

  The rotation load member 52 applies a load to the rotation of the idle gear 44 and generates a torque for turning the pair of idle gears 44 around the rotation axis of the center gear 43. Here, the rotation gear 52 is applied to the idle gear mounting shaft 512. It is an elastic member such as a spring that passes through and applies an upward force along the rotation axis to the idle gear 44.

In this embodiment, as shown in FIG. 5, the rotary load member 52 is passed through the floating gear mounting shaft 512, the idle gear 44 is passed from above, and the pressing member 53 that presses the idle gear 44 is passed from above. Thus, an upward force is applied from the rotary load member 52 to the idle gear.
The pressing member 53 is configured to engage with a concave groove 513 formed along the circumferential direction on the outer peripheral surface of the floating gear mounting shaft 512.

  Next, the power non-transmission state holding mechanism 60 will be described.

As shown in FIGS. 4 and 5, the power non-transmission state holding mechanism 60 urges the mounting member 51 to an intermediate position M where a pair of idle gears 44 are maintained in a power non-transmission position. A member 61 is provided.
The floating gear urging member 61 has one end attached to the attachment member 51 and the other end attached to a fixing member (not shown) fixed to the casing, for example, so that the attachment member 51 is positioned closest to the motor. It is an elastic member such as a spring that urges toward the door-side gear 42.
More specifically, the idle gear biasing member 61 connects the center of the center gear 43 and the center of the door side gear 42 in a state where the mounting member 51 is at the intermediate position M as shown in FIG. One end and the other end are arranged on a straight line, in other words, on a straight line orthogonal to a straight line connecting the centers of the pair of idle gears 44.

According to the power transmission mechanism 40 configured as described above, the door D can be opened or closed automatically or manually by switching to a power transmission state or a power non-transmission state.
Hereinafter, the operation when the power transmission mechanism 40 is switched to the power transmission state or the power non-transmission state will be described.

First, in the power non-transmission state, as shown in FIG. 4B, the mounting member 51 is biased to the intermediate position M by the above-described floating gear biasing member 61, and both the pair of floating gears 44 are doors. It does not mesh with the side gear 42.
Here, when a predetermined voltage is applied to the motor M to drive the motor M, the center gear 43 rotates, and the pair of idle gears 44 are tangentially connected to the pair of idler gears 44 through the portions engaged with the center gear 43. Power is added.
Then, as shown in FIGS. 4A and 4C, the tangential force resists the biasing force of the floating gear biasing member 61 so that the pair of floating gears 44 are rotated around the rotation axis of the center gear 43. The one or the other idle gear 44 moves to the forward rotation power transmission position or the reverse rotation power transmission position and meshes with the door side gear 42 to switch from the power non-transmission state to the power transmission state.

  On the other hand, when the motor M is stopped in the power transmission state, the attachment member 51 is again urged to the intermediate position M by the idle gear urging member 61, so that the pair of idle gears 44 move to the power non-transmission position. The power transmission state is switched to the power non-transmission state.

<Auxiliary mechanism>
Next, the auxiliary mechanism 30 will be described.

The auxiliary mechanism 30 generates an auxiliary force for opening the door D. Here, the auxiliary mechanism 30 is provided from one end side to the other end side of the upper portion of the door D and is accommodated in the casing C.
Specifically, as shown in FIGS. 2 and 3, the slide member 34 is slidable in conjunction with the rotation of the drive gear 45, and the predetermined rotation axis T <b> 2 is interlocked with the slide movement of the slide member 34. An auxiliary force applying member 32 that is provided so as to be rotatable around and rotates around the rotation axis T <b> 2 to contact the housing H and applies the auxiliary force to the door D is provided.

The slide member 34 has a long shape and is configured to be slidable in the extending direction thereof. The auxiliary force applying member 32 is provided at one end 341, and power is transmitted from the power transmission mechanism 40 to the other end 342. Is transmitted.
In the present embodiment, as shown in FIG. 6, the rotational power in the drive gear 45 (door side gear 42) is converted into the power in the extending direction in the slide member 34 between the slide member 34 and the power transmission mechanism 40. A power conversion mechanism 70 for conversion is interposed.
The power conversion mechanism 70 uses a so-called ratchet mechanism, and includes a claw portion 71 provided at the other end 342 of the slide member 34 and a drive gear 45 (door) disposed in the vicinity of the other end 342. The side gear 42) is composed of, for example, a plurality of protrusions 72 (three in this case) provided on the back surface.
With this configuration, when the drive gear 45 rotates, any one of the protrusions 72 presses the claw 71, and the power in the rotation direction of the drive gear 45 extends in the slide member 34 via the claw 71. Is transmitted to the slide member 34, and the slide member 34 slides in the extending direction.

As shown in FIGS. 2 and 3, the auxiliary force applying member 32 has a penetrating member 322 that penetrates through a through hole 31 a formed in one end 341 of the slide member 34. It is configured to be attached to the slide member 34 by being inserted into the through hole 31a.
The auxiliary force applying member 32 further includes a collision portion 321 that collides with the front surface of the housing H by rotating around the rotation axis T2.
With this configuration, the slide member 34 slides from the other end portion 342 toward the one end portion 341, so that the penetrating member 322 serves as a force point, the collision portion 321 serves as an action point, and the auxiliary force is applied to the door D. By acting, the magnetization of the door D and the housing H can be removed.

<No-tooth gear rotation mechanism>
Here, as shown in FIG. 7, the missing gear 46 of the present embodiment is provided so as to be rotatable about the axis X <b> 1 of the hinge axis Z.
The refrigerator door opening / closing mechanism 100 according to the present embodiment further includes a partial gear rotation mechanism 80 that rotates and moves the partial gear 46, as shown in FIG.

First, the missing gear 46 will be described.
The cut-out gear 46 has a shape in which a portion of the gear in which teeth are formed on the entire circumference is cut out in the circumferential direction (here, a shape in which approximately 3/4 along the circumferential direction is cut out). And teeth are formed on a part or all of the outer periphery thereof.

  The missing tooth gear 46 of the present embodiment has one or a plurality of through holes 46a formed so as to penetrate in the thickness direction, and a step for holding the missing gear 46 is provided in the through hole 46a. A holding member B such as a screw is provided.

  With the configuration described above, the toothless gear 46 can rotate within a predetermined range about the axis X1 of the hinge axis Z without moving in the vertical direction.

Next, the missing gear rotation mechanism 80 will be described.
As shown in FIG. 7, the missing gear rotating mechanism 80 is configured such that the missing gear 46 is interlocked with the opening / closing movement of the door D to drive the gear 45 (here, the door side gear 42 located closest to the door). Between the contact position P that is in contact with the drive gear 45 and the non-contact position Q that is not in contact with the drive gear 45.

  Here, the contact position P is a position where the missing gear 46 first contacts the drive gear 45 when the door D in the closed position moves in the opening direction, as shown in FIG. As shown in FIG. 7B, the non-contact position Q is a position where the missing gear 46 is the furthest away from the drive gear 45, and in this embodiment, the missing gear in a state where the door D is in the closed position. 46 position.

  Specifically, as shown in FIG. 7, the partial gear rotation mechanism 80 includes a partial gear biasing member 81 that biases the partial gear 46 from the non-contact position Q toward the contact position P, and a rotation shaft T3. A rotating member 82 which is provided so as to be rotatable around and rotates around the rotation axis T3 and presses the missing gear 46 to rotate the missing gear 46 from the contact position P to the non-contact position Q. It is correct.

The missing gear biasing member 81 is an elastic member such as a spring having one end attached to, for example, the back surface of the missing gear 46 and the other end attached to the rotation shaft T <b> 3 of the rotating member 82.
Note that the other end of the toothless gear biasing member 81 is not necessarily attached to the rotation shaft T3, and an attachment portion for attaching the other end of the toothless gear biasing member 81 is provided separately from the rotation shaft T3. You may provide in upper part.

As shown in FIG. 7, the rotating member 82 is fixed to, for example, a hinge plate (not shown) that connects the door D and the housing H, and one end 821 abuts on the toothless gear 46 and the other end. 822 contacts the casing C.
Here, the one end 821 is in contact with, for example, a notched end surface of the toothless gear 46, and the other end 822 is in contact with a side surface of the casing C.

In this embodiment, at least the other end 822 of the side surface is in contact with the other end 822 so that the other end 822 moves smoothly along the side surface of the casing C in conjunction with the opening and closing movement of the door D. The guide surface C1 is curved outward.
Note that the other end portion 822 of the rotating member 82 does not necessarily need to be in contact with the side surface of the casing C, and a guide surface for smoothly moving the other end portion 822 of the rotating member 82 is separate from the side surface of the casing C. You may provide in the upper part of the door D.

  With the configuration described above, when the door D in the open state starts to rotate about the axis X1 of the hinge shaft Z toward the closed position, the other end 822 of the rotating member 82 is pressed against the guide surface C1 of the casing C. Then, it rotates around the axis X2 of the rotation axis T3 while sliding along the guide surface C1. At this time, the one end portion 821 of the rotating member 82 presses the end surface of the missing gear 46, and this pressing force resists the biasing force of the missing gear biasing member 81 so that the missing gear 46 is not contacted from the contact position P. Rotate and move toward position Q.

  On the other hand, when the door D in the closed position starts to rotate about the axis X1 of the hinge shaft Z in the opening direction, the missing gear 46 is moved from the non-contact position Q to the contact position by the missing gear biasing member 81. The toothless gear 46 comes into contact with the drive gear 45 by rotating toward P. At this time, the rotating member 82 rotates around the axis X2 of the rotation axis T3 in a direction in which the one end 821 is away from the toothless gear 46, and the other end 822 is in contact with the guide surface C1 along with this rotation. Slide along the guide surface C1.

  Hereinafter, the operation of the refrigerator door opening and closing mechanism 100 of the present embodiment will be described.

First, the case where the door D in the closed position is moved in the opening direction will be described.
In this case, first, the motor M is driven by receiving a control signal from a control unit (not shown), and the drive gears 45 start to rotate in conjunction with each other. At this time, the swing mechanism 50 causes the pair of idle gears 44 to move from the power non-transmission position to the power transmission position. Further, the missing tooth gear rotation mechanism 80 holds the missing tooth gear 46 at the non-contact position Q.
Next, the rotational power of the drive gear 45 is transmitted to the slide member 34 via the power conversion mechanism 70 interposed between the power transmission mechanism 40 and the auxiliary mechanism 30, and the slide member 34 slides in the extending direction. . More specifically, a protrusion 72 provided on the back surface of the drive gear 45 is provided on the other end 342 of the slide member 34 by the rotation of the drive gear 45 located near the other end 342 of the slide member 34. By pressing the claw portion 71, the slide member 34 slides.
By this sliding movement of the slide member 34, the auxiliary force applying member 32 rotates around the rotation axis T2 and is pressed against the front surface of the housing H, and by the reaction, the door D and the housing H are demagnetized, The door D rotates around the hinge axis Z in the opening direction from the closed position.
When the door D is rotated in the opening direction, the missing gear rotating mechanism 80 rotates the missing gear 46 from the non-contact position Q to the contact position P around the axis X1 of the hinge shaft Z. More specifically, the casing C is rotated together with the door D about the axis X1 of the hinge axis Z, and in conjunction with this, the missing gear 46 is non-rotated by the biasing force of the missing gear biasing member 81. It rotates from the contact position Q to the contact position P. At this time, the rotating member 82 rotates around the axis X2 of the rotation axis T3 in a direction in which the one end 821 is away from the toothless gear 46, and the other end 822 is in contact with the guide surface C1 along with this rotation. Slide along the guide surface C1.
Thereafter, when the drive gear 45 further rotates, the drive gear 45 and the toothless gear 46 mesh with each other, and the door rotates in the opening direction.

Then, the case where the door D stopped in the open state is rotationally moved toward the closed position will be described.
When the motor M receives a control signal from a control unit (not shown) and is driven while the door D is stopped, the drive gears 45 start to rotate in conjunction with each other, and the swing mechanism 50 causes a pair of idle gears. 44 moves from a power non-transmission position to a power transmission position.
At this time, since the missing gear 46 is in the contact position P, the power of the motor M is transmitted to the hinge shaft Z, and the door D rotates and moves toward the closed position.
Thereafter, when the door D reaches a predetermined opening angle, the guide surface C <b> 1 of the casing C comes into contact with the other end 822 of the rotating member 82.
When the door D further rotates from here toward the closing position, the rotating member 82 rotates around the rotation axis T3, and the one end 821 of the rotating member 82 presses the missing gear 46. The pressing force counteracts the biasing force of the missing gear biasing member 81 to rotate the missing gear 46 from the contact position P toward the non-contact position Q.
As a result, the power of the motor M is not transmitted to the hinge axis Z, but then the door D further rotates and reaches the closed position by the inertia and the magnetic force of the housing H.

By the way, as described above, the toothless gear 46 of the present embodiment has a shape in which a part of the circumferential direction in the gear having teeth formed on the entire circumference is cut out.
For this reason, when the door D is moved in the opening direction with the drive gear 45 meshing with the toothless gear 46, for example, when the door D is opened large due to inertia, such as when the door D is stored in a large amount, the drive gear 45 May come off from the missing gear 46. If it does so, it will become impossible to close the door D automatically, after meshing | releasing.

Therefore, in the refrigerator door opening / closing mechanism 100 of the present embodiment, when the drive gear 45 that has meshed with the missing gear 46 is detached from the missing gear 46 due to the movement of the door D in the opening direction, this meshing is disengaged. Further, a return mechanism 200 for moving the door D in the closing direction so as to mesh the drive gear 45 with the toothless gear 46 again is further provided.
Hereinafter, the return mechanism 200 will be described with reference to FIGS.

<Return mechanism>
The return mechanism 200 moves the door D in a state where the engagement between the missing gear 46 and the drive gear 45 is disengaged in a closing direction to a position where the missing gear 46 and the drive gear 45 are engaged. Specifically, as shown in FIG. 8, the bending member 201 is provided on the lower side of the refrigerator R and has an elastic force, and a contact member 202 that contacts the bending member 201 and bends the bending member 201. It has.

In the present embodiment, as shown in FIG. 9, the door D is moved in the opening direction, and the maximum opening position K at which the opening angle of the door D is maximized from the disengagement position J where the drive gear 45 is disengaged from the missing gear 46. The bending member 201 and the contact member 202 are configured to come into contact with each other in a state where there is a door.
That is, when the door D moving in the opening direction reaches the meshing disengagement position J, the bending member 201 and the contact member 202 come into contact with each other from a non-contact state, and the meshing disengagement position J to the maximum opening position K. While the door D moves, the bending member 201 and the contact member 202 are kept in contact with each other. The opening angle of the door D at the meshing disengagement position J is 90 degrees or more, and is designed to be 130 degrees here, and the opening angle of the door D at the maximum opening position K is designed to be 160 degrees or more, for example. doing.
Note that the bending member 201 and the contact member 202 in FIG. 9 are schematically illustrated for convenience of explanation.

The bending member 201 is attached to the door D and rotates integrally with the door D. Here, the bending member 201 is provided on the lower surface of the door D and is provided at the rotation center of the door D (that is, the axis of the hinge axis Z). X1) rotate around.
Specifically, this is, for example, a plate made of resin or the like, and here, the long plate member has a shape bent one or more times in plan view.
For example, the bending member 201 is provided with a fixing portion 201a with the door D at one end portion, and with a contact portion 201b with a contact member 202 to be described later on the other end portion. It is configured to bend while being elastically deformed as a bending center α in the fixed portion 201a.

The contact member 202 is arranged so that the contact portion 201b (here, the other end portion) of the flexible member 201 comes into contact with the door D when the door D moves in the opening direction. It is fixed to the lower side and the bottom surface of the housing H so as not to rotate.
The contact member 202 of this embodiment has a contact surface 202a that moves while the bending member 201 is in contact with the movement of the door D in the opening direction. Here, as shown in FIG. 8, the contact surface 202 a is formed by using, for example, an existing half-opening prevention cam 203. More specifically, a protrusion F that protrudes outward is provided on the side surface of the half-opening prevention cam 203, and an inclined surface from the side surface of the protrusion F is defined as the contact surface 202a.

A specific design method of the contact surface 202a will be briefly described with reference to FIGS.
First, as shown in FIG. 10A, the locus of the design contact point with the contact surface 202 of the bending member 201 is drawn, and a rotation locus CH about the bending center α is drawn.
Next, a tangent line LO that touches the rotation locus CH and passes through the rotation center β of the bending member 201 (that is, the axis X1 of the hinge axis Z) is drawn. The tangent line LO is on the above-described design contact point side with respect to the deflection center α.
Then, a straight line LC is drawn which passes through the intersection γ between the virtual circle CT centered on the rotation center β and the tangent line LO, and an angle δθ formed with the tangent line LO becomes a predetermined angle. Note that the radius of the virtual circle CT is determined by a preset degree of bending of the bending member 201.

Next, as shown in FIG. 10B, the door D is in a different position between the position where the bending member 201 starts to contact the contact member 202 and the position where the door D is most open. A straight line LC is drawn by the above method.
Finally, as shown in FIG. 11, the outer edge of the contact surface 202a described above is designed by drawing an arc passing through an intersection C where a plurality of straight lines LC intersect. The design accuracy can be improved as the number of straight lines LC increases.

  The contact surface 202a of the present embodiment is formed such that an angle δθ formed by the tangent line LO and the straight line LC is 30 degrees or more and 60 degrees or less, and δθ is 45 degrees here.

  Next, the refrigerator door control device 110 that controls the movement of the door D by the refrigerator door opening / closing mechanism 100 described above, that is, the moving speed of the door D will be described.

<Fridge door control device>
As shown in FIG. 12, the refrigerator door control device 110 according to the present embodiment is connected to the motor drive circuit L that drives the motor M described above and controls the motor M. Physically, the CPU , A memory, an A / D converter, and the like. Then, by cooperation of the CPU and peripheral devices according to the program stored in the predetermined area of the memory, as shown in FIG. 13, the zero setting unit 91, the opening angle detection unit 92, the induced voltage detection unit 93, the target induction, The voltage storage unit 94 and the applied voltage control unit 95 are configured to exhibit functions.
In the following, the operation of the refrigerator door control device 110 will be described with the explanation of each part.

First, when a voltage is applied to the motor M via the motor drive circuit L in a state where the door D is in the closed position, the drive gear 45 rotates in conjunction with the motor M as described above, and either The two protrusions 72 press the claw 71 and the auxiliary mechanism 30 is activated.
At this time, since the load applied to the motor M increases from when the auxiliary mechanism 30 starts to operate until the door D and the housing H are demagnetized, the operation speed of the motor decreases, and this is compensated. Therefore, the voltage applied to the motor gradually increases.

  The zero setting unit 91 sets the door opening angle to zero when the applied voltage for moving the door D in the opening direction reaches a predetermined threshold in a state where the door D is closed. In other words, the zero setting unit 91 sets a detection start point of the opening angle when the applied voltage becomes a predetermined threshold value.

The opening angle detection unit 92 detects the opening angle from the opening angle zero set by the zero setting unit 91. In other words, the opening angle detection unit 92 detects the opening angle from the detection start point set by the zero setting unit 91. start.
In this embodiment, as shown in FIGS. 3 and 6, the drive gear 45 is provided with a rotary switch RS, and the opening angle detection unit 92 acquires a signal output from the rotary switch RS, and Calculate the opening angle. As for the rotary switch RS, here is a so-called absolute type rotary encoder that outputs, for example, a 4-bit signal in accordance with the rotation of the drive gear 45, and the opening angle detector 92 is based on this signal. The opening / closing direction and opening angle of D can be calculated.

The induced voltage detector 93 detects an induced voltage generated when the motor M is rotating, and transmits an induced voltage signal indicating the induced voltage to an applied voltage controller 95 described later.
In the present embodiment, as shown in FIG. 12, the induced voltage signal is analogly input to the induced voltage detector 93 using a voltage dividing resistor r provided in the motor drive circuit L.

The target induced voltage storage unit 94 is formed in a predetermined area of the memory, and stores a target value of an induced voltage that is predetermined according to the opening angle of the door D.
This target value is set so that the moving speed of the door D becomes a predetermined speed according to the opening angle. For example, as the closed door D moves in the opening direction, the moving speed gradually increases. It is set to decrease.
In the present embodiment, the movement angle range of the door D (hereinafter also simply referred to as the movement range) is divided into a plurality of continuous divided ranges, and the target value is stored for each divided range. Each divided range may be, for example, a range obtained by dividing the moving range by a certain angle, or may be a range obtained by dividing the moving range so that the angles of the divided ranges are different from each other.

The applied voltage control unit 95 acquires the induced voltage signal from the induced voltage detection unit 93, compares the detected value of the induced voltage with the target value stored in the target induced voltage storage unit 94, and The voltage applied to the motor M is controlled so that the detected value becomes the target value.
As shown in FIGS. 12 and 13, the applied voltage control unit 95 of the present embodiment outputs an ON / OFF signal to a switching element SW such as a MOSFET constituting the motor drive circuit L and performs PWM control on the applied voltage. The duty ratio is changed so that the detected value becomes the target value.

  According to the refrigerator door opening / closing mechanism 100 according to the present embodiment configured as described above, when the auxiliary mechanism 30 generates the auxiliary force, the missing gear rotation mechanism 80 causes the missing gear 46 to move to the non-contact position Q. Therefore, the door D and the housing H can be demagnetized in a state where the drive gear 45 and the toothless gear 46 are not engaged with each other, and the torque of the motor M necessary for demagnetizing. Thus, the motor can be reduced in size.

In addition, since the drive gear 45 is a gear having teeth on the entire periphery, the missing gear 46 can be reliably meshed with the drive gear 45 regardless of the posture (rotation angle) of the drive gear 45.
Thus, problems that may occur in the past, that is, problems that can be caused by manually opening the door D, and complicated control can be prevented, and the refrigerator door opening / closing mechanism 100 is more practical than the conventional one. Can be.

  Further, since the motor M is provided at the upper part of the door D, a link member required when the motor M is provided at the upper part of the housing H can be eliminated, and the user puts his / her hand in the link member. Can be prevented and the appearance of the appearance can be improved.

  In addition, the swing mechanism 50 can switch between a power transmission state and a power non-transmission state by moving the pair of idle gears 44 along a plane perpendicular to the rotation axis of the center gear 43, and the conventional clutch mechanism Thus, a mechanism for moving the gear in the height direction can be eliminated, and the power transmission mechanism 40 can be made compact in the height direction.

  In addition, since the pair of idle gears 44 moves along a plane perpendicular to the rotation axis of the center gear 43 in conjunction with the rotation of the center gear 43, the idle gear 44 can be moved using the power of the motor M. Thus, a dedicated actuator for moving the idle gear 44 can be eliminated.

  Further, since the power non-transmission state holding mechanism 60 is configured using the idle gear biasing member 61, the power non-transmission state holding mechanism can be simplified, and the entire mechanism is inexpensive and lightweight. Can be.

Further, when the door D is moved in the opening direction, for example, when the door D is stored in a large amount, even if the door D is largely opened due to inertia and the drive gear 45 is disengaged from the toothless gear 46, the return mechanism 200 However, since the drive gear 45 is meshed with the missing gear 46 again, the door D can be automatically closed again after meshing.
Of course, even when the user manually opens the door D largely, the return mechanism 200 can re-engage the disengaged drive gear 45 with the toothless gear 46 and automatically close the door D again.

  Furthermore, since the angle δθ formed between the tangent line LO and the straight line LC is set to 45 degrees, the restoring force of the bending member 201 can be used as the force for rotating the door D in the closing direction most efficiently.

  In addition, while the door D moves from the meshing disengagement position J to the maximum opening position K, the bending member 201 and the contact member 202 are configured to keep in contact with each other. After that, the drive gear 45 can be reliably meshed with the toothless gear 46 even when the door D opens more or less.

  In addition, since the bending member 201 is provided on the lower surface of the door D and the contact member 202 is provided on the lower side of the hinge axis Z or the bottom surface of the housing H, these members 201 and 202 are exposed. Therefore, the appearance can be prevented from deteriorating.

  In addition, since the contact member 202 is configured using a part of the existing half-door prevention cam 203, the return mechanism 200 can be configured without unnecessarily increasing the number of components.

Moreover, according to the refrigerator door control device 110 according to the present embodiment configured as described above, the induced voltage of the motor M is controlled so as to become a predetermined target value according to the opening angle of the door D. Therefore, the moving speed of the door D can be set to a speed corresponding to the target value, and can be controlled to a desired speed regardless of the storage amount of the door D.
In addition, since the moving speed of the door D is set to a desired speed by controlling the induced voltage to the target value, a dedicated sensor for detecting the moving speed of the door D is not necessary.

By the way, when the door opening / closing mechanism 100 for refrigerator mentioned above moves the door D in an obstruction | occlusion position to an opening direction, the protrusion part 72 presses the nail | claw part 71 by moving the motor M, and act | operates the auxiliary mechanism 30. The standby position of the protrusion 72 in a state where the door D is in the closed position is not the same position every time. For this reason, the time from when the motor M starts to move until the door D starts to open is not always constant.
In such a configuration, according to the refrigerator door control device 110 according to the present embodiment, the zero setting unit 91 sets the opening angle to zero when the applied voltage for opening the door D reaches a predetermined threshold. Therefore, the opening angle can be set to zero at substantially the same timing each time. Therefore, even if there is a time difference between when the motor M starts to move and when the door D starts to open, the opening angle detected from the opening angle zero does not vary, and the opening angle can be detected with high accuracy.

  Furthermore, since the opening angle detection unit 92 detects the opening angle based on the signal output from the rotary switch RS, the apparatus configuration can be simplified and inexpensive, and the moving direction (opening / closing direction) of the door D can be changed. I can know.

<Modification of First Embodiment>
The present invention is not limited to the above embodiment.

  In the embodiment, the guide surface that guides the movement of the other end of the rotating member is a curved surface that bulges outward, but may be a curved surface or a flat surface that is recessed inward.

  In the embodiment, a plurality of motor-side gears and door-side gears are provided, but the number thereof is not limited, and any gear may be used.

  Furthermore, in the above-described embodiment, the rotational load member is an elastic member. However, for example, it may be one that causes friction between the idler gear and the mounting member. Examples thereof include a sheet member and a magnetic resistance such as a magnet.

  In addition, in the return mechanism of the above embodiment, the bending member rotates integrally with the door and the contact member is fixed to the hinge shaft or the housing. However, the bending member is fixed to the hinge shaft or the housing. The contact member may be configured to rotate integrally with the door.

  The return mechanism may be provided on the upper side of the refrigerator. Specifically, for example, the bending member may be provided on the upper side of the door, and the contact member may be provided on the upper side of the hinge shaft or the upper surface of the housing.

  Furthermore, the shape of the bending member is not limited to a plate shape, and may be changed as appropriate, such as a rod shape or a block body shape.

  In addition, the contact surface is not limited to the shape designed by the design method of the above embodiment, and may be, for example, an inclined surface that is inclined at a predetermined angle with respect to the rotation direction of the contact portion of the flexible member, or a curved surface. It may be a plane or a plane.

  Regarding the refrigerator door control device, the opening angle detection unit of the above embodiment detects the opening angle based on the signal output from the rotary switch, but the drive gear is provided with an incremental rotary encoder. Then, based on the signal output from this encoder, the opening angle detection unit may detect the opening angle.

  In the above embodiment, the target value of the induced voltage is set so that the moving speed gradually decreases as the door moves in the opening direction. For example, the door moves in the opening direction. Accordingly, it may be set so as to gradually decrease after initially increasing, or may be changed as appropriate.

  In addition, the toothless gear rotation mechanism 80 is configured to rotate the toothless gear 46 by the rotational movement of the rotation member 82 in the above embodiment, but as shown in FIG. Instead, the missing gear 46 may be configured to rotate using the slide member 83.

  More specifically, the toothless gear rotating mechanism 80 interlocks with the opening / closing movement of the door D to move the toothless gear 46 to the drive gear 45 (here, the door side gear 42 located closest to the door). A non-contact gear that rotates between the contact position P and the non-contact position Q that is not in contact with the drive gear 45 and biases the non-tooth gear 46 from the non-contact position Q toward the contact position P. An urging member 81 and a slide member 83 that slides in conjunction with the rotational movement of the door D are provided.

  The missing gear biasing member 81 has the same configuration as that of the above embodiment, and the description thereof is omitted here.

When the door D in the open state moves to the closed position, the slide member 83 presses the toothless gear 46 to rotate from the contact position P to the non-contact position Q, and the door D is in the closed position. In this state, the one end portion 831 is in contact with the toothless gear 46 and the other end portion 832 is in contact with the casing C.
Specifically, this is a flat plate here, and slides in one end 831 and the other end 832 in a long hole HPa provided in, for example, a hinge plate HP connecting the door D and the housing H. A sliding portion 833 is provided. In addition, the structure which provided the long hole in the one end part 831 and the other end part 832 of the slide member 83, and provided the sliding part in the hinge plate HP may be sufficient.

  The slide member 83 of the present embodiment is formed with a long hole 83a through which a mounting portion T3 for attaching the missing gear biasing member 81 is slidably inserted. However, the shape of the slide member 83 is changed as appropriate. It doesn't matter.

  With the configuration described above, as shown in FIG. 15, when the door D in the open state starts to rotate about the axis X1 of the hinge shaft Z toward the closed position, the other end portion 832 of the slide member 83 is moved to the casing C. Each of the sliding portions 833 slides in the long hole HPa. At this time, the one end portion 831 of the slide member 83 presses the end surface of the missing gear 46, and this pressing force resists the biasing force of the missing gear biasing member 81 so that the missing gear 46 is not contacted from the contact position P. Rotate and move toward position Q.

  On the other hand, when the door D in the closed position starts to rotate about the axis X1 of the hinge shaft Z in the opening direction, the missing gear 46 is moved by the missing gear biasing member 81 as shown in FIG. The toothless gear 46 contacts the drive gear 45 by rotating from the non-contact position Q toward the contact position P. At this time, the slide member 83 slides in a direction in which the one end portion 831 is separated from the toothless gear 46, and the other end portion 832 slides along the guide surface C1 while coming into contact with the guide surface C1 along with the slide movement. To do.

  The present invention is not limited to the above embodiment.

Second Embodiment
Below, the door opening and closing mechanism for refrigerators in 2nd Embodiment is demonstrated with reference to FIG.16 and FIG.17. The refrigerator door opening / closing mechanism in the second embodiment is different from the first embodiment in the configuration of the toothless gear rotating mechanism 80, and uses the magnetic force of the magnet instead of the elastic force such as the spring in the first embodiment. It is composed. Hereinafter, the missing gear rotation mechanism 80 will be described. The movement of the missing gear 46 is the same as in the first embodiment.

  As shown in FIGS. 16 and 17, the missing gear rotation mechanism 80 of the present embodiment is connected to the missing gear 46 and abuts against a contacted portion 804 fixed to the housing side. A link member 801 that is moved by a magnetic force between a position P1 and a separation position Q1 that is separated from the contacted portion 804, and provided on the door side, contacts the link member 801 when the door is in the closed position. And a regulating member 802 that regulates the movement of the link member 801.

The link member 801 is attached to a hinge plate HP that connects, for example, a door and a housing so as to be rotatable around a predetermined rotation axis 80X, and a missing gear 46 is attached to one end 801a.
The link member 801 according to the present embodiment is attracted by a magnetic force to the metal contacted portion 804 provided on the hinge plate HP, and thus rotates and moves from the separated position Q1 to the contact position P1. 46, and specifically includes a magnet 803 positioned in the vicinity of the contacted portion 804 without contacting the contacted portion 804 when the door is in the closed position.

  The restriction member 802 is provided in the casing C, for example, and moves together with the door. When the door is in the closed position, the restriction member 802 comes into contact with the other end 801b of the link member 801, and the magnet 803 comes into contact. This prevents the portion 804 from being drawn.

  With the configuration described above, as shown in FIG. 17, when the door in the open state starts to rotate about the axis X1 of the hinge axis Z toward the closed position, the other end 801b of the link member 801 is moved to the casing C. It is pressed against the guide surface C1 and rotates around the rotation axis 80X while sliding along the guide surface C1. At this time, the one end 801a of the link member 801 presses the end face of the missing gear 46, and rotates the missing gear 46 from the contact position P toward the non-contact position Q.

  On the other hand, when the door in the closed position starts to rotate about the axis X1 of the hinge axis Z in the opening direction, the regulating member 802 moves in a direction away from the other end 801b of the link member 801. As a result, the magnet 803 is attracted to the contacted portion 804 by the magnetic force, and the link member 801 rotates and moves from the separation position Q1 to the contact position P1. To the contact position P and mesh with the drive gear 45.

<Modification of Second Embodiment>
The missing gear rotating mechanism 80 of the above embodiment is configured to rotate the missing gear 46 when the magnet 803 is attracted to the contacted portion 804. However, as shown in FIG. By providing the second magnet 805 that repels the magnet 803 in the abutted portion 804, both the magnets 801 and 803 may repel so that the toothless gear 46 is rotated.

<Third Embodiment>
Below, regarding the refrigerator door opening / closing mechanism 100 in the third embodiment, the swing mechanism 50 and the power non-transmission holding mechanism 60 which are different from the above embodiment will be described.

Although the swing mechanism in the above embodiment has a single mounting member, the swing mechanism in the second embodiment has a pair of mounting members 51 (hereinafter referred to as these) as shown in FIGS. Are also referred to as a first attachment member 51a and a second attachment member 51b).
Note that the rotation load member 52 and the pressing member 53 have the same configuration as that of the above embodiment, and a description thereof will be omitted.

Specifically, as shown in FIG. 20, the mounting member 51 includes a flat plate member 511 having a through-hole 51h formed so as to penetrate in the thickness direction, and an idle gear that stands up from the flat plate member 511 and to which an idle gear is attached. And a mounting shaft 512 for use.
The through hole 51h has a substantially circular shape and is formed larger than the diameter of the center gear mounting shaft 7 to which the center gear 43 is mounted. Accordingly, the attachment member 51 can be passed through the center gear attachment shaft 7 through the through hole 51h, and the attachment member 51 can rotate around the center gear attachment shaft 7.

  In the assembled state as described above, the swing mechanism 50 of the present embodiment is configured so that the first mounting member 51a and the second mounting member 51b are directed toward the door side gear 42 as shown in FIG. The opening angle θ1 is configured. In other words, the opening angle θ <b> 1 is an angle formed by the rotation axes of the idle gears 44 a and 44 b around the rotation axis of the center gear 43.

  In the second embodiment, the step portion 514 formed on the flat plate member 511 of each attachment member 51 is located within the opening angle θ1. Each attachment member 51 is provided with an angle restricting portion 515 that is formed on the opposite side of the step portion 514 with respect to the center gear attachment shaft 7 and restricts the opening angle θ1.

Specifically, as shown in FIGS. 19 and 20, the angle restricting portion 515 is a protruding portion that protrudes outward from the outer surface of the flat plate member 511. When the opening angle θ1 is reduced, the distance between the angle restricting portions 515 is reduced. When the opening angle θ1 reaches a predetermined angle, the angle restricting portions 515 come into contact with each other.
With the configuration described above, each of the idle gears 44a and 44b is not closer than a predetermined distance, and both of the idle gears 44a and 44b can be prevented from meshing with the door-side gear 42.

  Next, the power non-transmission state holding mechanism 60 in the second embodiment will be described.

  As shown in FIG. 19, the power non-transmission state holding mechanism 60 regulates the movement of the pair of idle gears 44 by the above-described swing mechanism 50 so that each idle gear 44 meshes with the door side gear 42. In this state, the power of the motor M is not transmitted to the door side gear 42 and the power is not transmitted. In the power non-transmission state, the refrigerator door opening / closing mechanism 100 is in a manual mode in which the door D can be manually opened / closed.

  Specifically, as shown in FIG. 21 (a), this includes a restriction position X for restricting the movement of the pair of idle gears 44 by the swing mechanism 50, and a restriction position X as shown in FIG. 21 (b). A restriction member 61 that moves between the release position Y for releasing the restriction at the position, a biasing member 62 that biases the restriction member 61 to the restriction position X, and a restriction member 61 that moves from the restriction position X to the release position Y And a restriction release mechanism 63 to be operated.

The restricting member 61 is configured to be capable of moving forward and backward with respect to the door-side gear mounting shaft 8 to which the door-side gear 42 is attached. Specifically, one end portion has a semicircular shape and the other end portion has a thickness. A through hole 61h penetrating in the direction is formed.
The through hole 61h has a substantially elongated hole shape and is formed larger than the diameter of the door-side gear mounting shaft 8. As a result, the restricting member 61 can be passed through the door-side gear mounting shaft 8 through the through hole 61h, and the restricting member 61 can be moved forward and backward with respect to the door-side gear mounting shaft 8.

The restriction member 61 moves between the restriction position X and the release position Y by the above-described advance / retreat movement, and at the restriction position X, one end portion is interposed between the first attachment member 51a and the second attachment member 51b. Thus, the turning of the pair of idle gears 44 is restricted, and at the release position Y, the one end does not contact any of the first mounting member 51a and the second mounting member 51b, and the turning is permitted.
Here, at the restricting position X, one end portion of the restricting member 61 is configured to fit into a gap formed between the step portions 514 of the flat plate members 511 described above.

  The urging member 62 applies a urging force from the release position Y to the restriction position X with respect to the restriction member 61. In this embodiment, one end is attached to the restriction member 61 and the other end is, for example, a case. It is an elastic member such as a spring attached to the fixed member 9 that is fixed.

The restriction release mechanism 63 moves the restriction member 61 from the restriction position X to the release position Y. Here, the restriction release mechanism 63 is attached to the restriction member 61 and receives a control signal from a control unit (not shown), for example. A release force in a direction opposite to the biasing force is applied to the member 61.
More specifically, when the control signal is received, the restriction release mechanism 63 of the present embodiment is configured to instantaneously energize a solenoid (not shown), and to apply the release force to the restriction member 61 by this instantaneous energization. .

According to the above-described configuration, the pair of idle gears 44 rotate around the center gear 43 by the restriction release mechanism 63 moving the restriction member 61 from the restriction position X to the release position Y by instantaneous energization of a solenoid (not shown). It turns by the torque which it is going to make, and one or the other idle gears 44a and 44b mesh with the door side gear 42, and it switches from a power non-transmission state to a power transmission state.
At this time, when one or the other idler gear 44a, 44b meshes with the door side gear 42, the tangential force is applied to the idler gear 44 from the center gear 43 and the door side gear 42 via the meshed portions. Will be added. Thereby, when the power non-transmission state is switched to the power transmission state, the torque applied to the idle gear 44 increases, and the restriction member 61 remains at the release position Y against the urging force applied to the restriction member 61. At the same time, the power transmission state is maintained.

<Fourth embodiment>
Below, the door opening / closing mechanism 100 for refrigerators in 4th Embodiment is demonstrated with reference to FIGS.
In addition, the symbol attached | subjected to FIGS. 22-32 is used in description of 4th Embodiment.

  First, the refrigerator R according to the present embodiment will be described.

As shown in FIG. 22, the refrigerator R includes a housing H whose front surface is open and left and right doors D provided in the opening of the housing H, and the left and right doors D are centered on a predetermined rotation axis. It is comprised so that it may rotate.
Each door D is connected to the housing H by a hinge Z, for example.

The refrigerator door opening / closing mechanism 100 is for opening and closing each door D of the refrigerator R described above, and is provided on the upper surface of the refrigerator R for each of the left and right doors D.
In the present embodiment, each of the refrigerator door opening / closing mechanisms 100 has the same configuration, and hereinafter, the refrigerator door opening / closing mechanism 100 for opening and closing the right door D will be described as a representative.

Specifically, as shown in FIG. 23, the refrigerator door opening / closing mechanism 100 includes a drive mechanism 10 provided on the upper surface of the housing H, a link mechanism 20 that transmits power of the drive mechanism 10 to the door D, and a link. The mechanism 20 includes an auxiliary mechanism 30 that assists when the door D is opened.
Hereinafter, each mechanism will be described.

<Drive mechanism>
The drive mechanism 10 outputs power for opening and closing the door D. Here, the drive mechanism 10 is accommodated in the casing C and attached to the upper surface of the housing H as shown in FIG.
Specifically, as shown in FIGS. 24 and 25, this has a motor M and a power transmission mechanism 40 that transmits the power of the motor M to the link mechanism 20.

  The motor M receives a control signal from a control unit (not shown) and rotates forward or backward. Here, for example, the motor M is configured to rotate at a predetermined rotational speed based on the control signal. Yes.

  The power transmission mechanism 40 is configured to switch between a power transmission state in which the power of the motor M is transmitted to the link mechanism 20 and a power non-transmission state in which the power is not transmitted to the link mechanism 20. The motor-side gear 41 that rotates in conjunction with the motor M, the door-side gear 42 that rotates in conjunction with the opening and closing of the door D, that is, the link mechanism 20, the center gear 43 that meshes with the motor-side gear 41, and the center gear 43 And a pair of idler gears 44 (hereinafter referred to as one idler gear 44a and the other idler gear 44b).

  In the present embodiment, a plurality of motor side gears 41 are connected in series, and among these, the motor side gear 41 located closest to the door is connected to the center gear 43. The pair of idle gears 44 that mesh with the center gear 43 are arranged so as to sandwich a straight line connecting the rotation shaft of the center gear 43 and the rotation shaft of the door side gear 42, and rotate in conjunction with the center gear 43.

As shown in FIGS. 24 and 25, the power transmission mechanism 40 according to the present embodiment rotates the center gear 43 to move the pair of idle gears 44 around the center gear 43 and the rotation shaft of the center gear 43. And a power non-transmission state holding mechanism 60 that makes a power non-transmission state in which none of the idle gears meshes with the door-side gear 42.
Note that the power transmission mechanism 40 shown in FIG. 25 is in a state in which the center gear 43, the pair of idle gears 44, and the door side gear 42 are removed in the automatic opening mode described above.

  The swing mechanism 50 includes a pair of idle gears 44, a forward rotation power transmission position where one idle gear 44 a meshes with the door side gear 42, and a reverse rotation power transmission position where the other idle gear 44 b meshes with the door side gear 42. And the pair of idle gears 44 are moved between the power non-transmission positions where the door-side gears 42 are not meshed with each other.

  The swing mechanism 50 according to the present embodiment turns a pair of idle gears 44 around the rotation axis of the center gear 43 along the rotation direction of the center gear 43, whereby one idle gear 44 a becomes the door side gear 42. The other idler gear 44b is separated from the door side gear 42, or the other idler gear 44b is engaged with the door side gear 42 and the one idler gear 44a is separated from the door side gear 42. .

  More specifically, as shown in the upper part of FIG. 24, when the center gear 43 rotates forward in conjunction with the rotation of the motor M (in this embodiment, counterclockwise when viewed from above), the pair of idle gears 44 is Turning around the rotation axis of the center gear 43 as viewed from above, it turns counterclockwise, and one free gear 44 a meshes with the door side gear 42. Thereby, the door opening / closing mechanism 100 for refrigerators of this embodiment will be in the automatic opening mode which the door D opens automatically with the motive power of the motor M. FIG.

  On the other hand, as shown in the lower part of FIG. 24, when the center gear 43 rotates reversely in conjunction with the rotation of the motor M (clockwise as viewed from above in this embodiment), a pair of idle gears 44 are connected to the center gear 43. The other idler gear 44b meshes with the door-side gear 42 by turning clockwise around the rotation axis as viewed from above. Thereby, the door opening / closing mechanism 100 for refrigerators of this embodiment will be in the automatic closing mode which the door D closes automatically with the motive power of the motor M. FIG.

  In the automatic opening mode and the automatic closing mode described above, the door-side gear 42, one or the other idler gear 44 meshing with the door-side gear 42, and the center gear 43 have an angle α of 90 degrees or more and In this embodiment, the angle α is designed to be not less than 110 degrees and not more than 120 degrees.

Next, a specific configuration of the swing mechanism 50 will be described.
As shown in FIG. 25 and FIG. 26, this rotates around the rotation shaft of the center gear 43, and is interposed between the mounting member 51 to which the idle gear is attached, and between the attachment member 51 and the idle gear. And a rotation load member 52 that applies a load to the rotation of each idle gear.

As shown in FIG. 26, the mounting member 51 has a flat plate member 511 having a through hole 51h formed so as to penetrate in the thickness direction, and a floating gear mounting shaft 512 that stands up from the flat plate member 511 and has a free gear mounted thereon. It consists of and.
The through hole 51h has a substantially circular shape and is formed larger than the diameter of the center gear mounting shaft 7 to which the center gear 43 is mounted. Accordingly, the attachment member 51 can be passed through the center gear attachment shaft 7 through the through hole 51h, and the attachment member 51 can rotate around the center gear attachment shaft 7.

  The rotational load member 52 applies a load to the rotation of the idle gear and generates torque for turning the pair of idle gears 44 around the rotation axis of the center gear 43. Here, the rotary load member 52 is attached to the idle gear attachment shaft 512. And an elastic member such as a spring that applies an upward force along the rotation axis to the idle gear 44.

In this embodiment, as shown in FIG. 26, the rotary load member 52 is passed through the idler gear mounting shaft 512, the idler gear 44 is passed from above, and the pressing member 53 that presses the idler gear is passed from above. Thus, an upward force is applied from the rotary load member 52 to the idle gear.
The pressing member 53 is configured to engage with a concave groove 513 formed along the circumferential direction on the outer peripheral surface of the floating gear mounting shaft 512.

  Here, as shown in FIGS. 24 and 25, the power transmission mechanism 40 of the present embodiment passes the first attachment member 51 a to which one idle gear 44 a is attached to the center gear attachment shaft 7, and the other from above. The floating gear 44b is assembled through the center gear 43 from above the second mounting member 51b to which the idle gear 44b is attached.

  In the assembled state as described above, the swing mechanism 50 of the present embodiment has a first mounting member 51a and a second mounting member 51b with a predetermined direction toward the door-side gear 42, as particularly shown in FIG. The opening angle θ1 is configured. In other words, the opening angle θ <b> 1 is an angle formed by the rotation axes of the idle gears 44 a and 44 b around the rotation axis of the center gear 43.

  In the present embodiment, the step portion 514 formed on the flat plate member 511 of each attachment member 51 is located within the opening angle θ1 and is formed on the opposite side of the step portion 514 with respect to the center gear attachment shaft 7. In addition, an angle restricting portion 515 for restricting the opening angle θ1 is provided.

Specifically, as shown in FIGS. 25 and 26, the angle restricting portion 515 is a protruding portion that protrudes outward from the outer surface of the flat plate member 511. When the opening angle θ1 decreases, the angle restricting portion 515 When the distance decreases and the opening angle θ1 reaches a predetermined angle, each angle restricting portion 515 is configured to come into contact.
With the configuration described above, each of the idle gears 44a and 44b is not closer than a predetermined distance, and both of the idle gears 44a and 44b can be prevented from meshing with the door-side gear 42.

  Next, the power non-transmission state holding mechanism 60 will be described.

  As shown in FIG. 28, the power non-transmission state holding mechanism 60 regulates the movement of the pair of idle gears 44 by the above-described swing mechanism 50 so that each idle gear 44 meshes with the door side gear 42. In other words, the power of the motor M is not transmitted to the door side gear 42, and the power is not transmitted. In this embodiment, in the power non-transmission state, the refrigerator door opening / closing mechanism 100 is in a manual mode in which the door D can be manually opened / closed.

  Specifically, as shown in the upper part of FIG. 28, this is a restriction position X that restricts the movement of the pair of idle gears 44 by the swing mechanism 50, and a restriction position X as shown in the lower part of FIG. A restriction member 61 that moves between the release position Y for releasing the restriction, a biasing member 62 that biases the restriction member 61 to the restriction position X, and a restriction that moves the restriction member 61 from the restriction position X to the release position Y. And a release mechanism 63.

The restricting member 61 is configured to be capable of moving forward and backward with respect to the door-side gear mounting shaft 8 to which the door-side gear 42 is attached. Specifically, one end portion has a semicircular shape and the other end portion has a thickness. A through hole 61h penetrating in the direction is formed.
The through hole 61h has a substantially elongated hole shape and is formed larger than the diameter of the door-side gear mounting shaft 8. As a result, the restricting member 61 can be passed through the door-side gear mounting shaft 8 through the through hole 61h, and the restricting member 61 can be moved forward and backward with respect to the door-side gear mounting shaft 8.

The restriction member 61 moves between the restriction position X and the release position Y by the above-described advance / retreat movement, and at the restriction position X, one end portion is interposed between the first attachment member 51a and the second attachment member 51b. Thus, the turning of the pair of idle gears 44 is restricted, and at the release position Y, the one end does not contact any of the first mounting member 51a and the second mounting member 51b, and the turning is permitted.
More specifically, at the restriction position X, one end portion of the restriction member 61 is configured to fit in a gap formed between the step portions 514 of the flat plate members 511 described above.

  The urging member 62 applies a urging force from the release position Y to the restriction position X with respect to the restriction member 61. In this embodiment, one end is attached to the restriction member 61 and the other end is, for example, a case. It is an elastic member such as a spring attached to the fixed member 9 that is fixed.

The restriction release mechanism 63 moves the restriction member 61 from the restriction position X to the release position Y. Here, the restriction release mechanism 63 is attached to the restriction member 61 and receives a control signal from a control unit (not shown), for example. A release force in a direction opposite to the biasing force is applied to the member 61.
More specifically, when the control signal is received, the restriction release mechanism 63 of the present embodiment is configured to instantaneously energize a solenoid (not shown), and to apply the release force to the restriction member 61 by this instantaneous energization. .

According to the power transmission mechanism 40 configured as described above, the door D can be opened and closed automatically or manually by switching to a power transmission state or a power non-transmission state.
Hereinafter, the operation when the power transmission mechanism 40 is switched to the power transmission state or the power non-transmission state will be described.

First, an operation for switching from the power non-transmission state to the power transmission state will be described.
Note that when switching to the power transmission state, which one of the idle gears 44 meshes with the door-side gear 42 is determined by the rotation direction of the motor M, and in either case, the operating principle is the same. Then, the case where one idle gear 44a meshes with the door side gear 42 as a representative and switches to a power transmission state is demonstrated.

In the power non-transmission state, as shown in FIG. 27, the restricting member 61 is biased to the restricting position X, and neither of the pair of idle gears 44 is engaged with the door side gear 42.
Here, when a predetermined voltage is applied to the motor M and the center gear 43 is rotated in the forward direction, a tangential force is applied to the pair of idle gears 44 through the portions engaged with the center gear 43.
Due to this tangential force, each idle gear 44 starts to rotate about the rotation axis. However, since the rotation load member 52 applies a load to the rotation of the idle gear, the force in the tangential direction causes the rotation torque to rotate the idle gear around the rotation axis and the idle gear to turn around the center gear 43. It is distributed to the swing torque.
At this time, in this embodiment, the urging force applied from the urging member 62 to the restricting member 61 resists the swing torque, and the restricting member 61 restricts the movement of the pair of idle gears 44 by the swing mechanism 50. To maintain the state (that is, the power non-transmission state).

In this state, for example, when a switching signal for switching from the power non-transmission state to the power transmission state is transmitted to a control unit (not shown), the control unit controls the voltage applied to the solenoid of the restriction release mechanism 63. The power is instantaneously applied, and an instantaneous release force is applied to the regulating member 61.
As a result, the restricting member 61 moves from the restricting position X to the release position Y, and the pair of idle gears 44 pivots around the center gear 43 due to the swing torque, and one idle gear 44a moves to the door side gear 42. To switch from the power non-transmission state to the power transmission state.

Thus, when one idle gear 44a meshes with the door side gear 42 and switches to the power transmission state, a force in the tangential direction is exerted on the one idle gear 44a via the meshed portion with the door side gear 42. Join.
As a result, the swing torque described above increases, and in this embodiment, the swing torque resists the urging force, and the regulating member 61 can remain in the release position Y without energizing the solenoid. .

Next, an operation for switching from the power transmission state to the power non-transmission state will be described.
In the power transmission state, as described above, the swinging torque resists the urging force and the power transmission state is maintained.
In this state, for example, when a switching signal for switching from the power non-transmission state to the power transmission state is transmitted to a control unit (not shown), the control unit controls the voltage applied to the motor M, and the motor M Stop or momentarily reverse the rotation.
As a result, the rotation of the center gear 43 stops or instantaneously reverses in conjunction with the motor M, and the swing torque described above decreases.
As a result, the urging force resists the swing torque, the restricting member 61 moves from the release position Y to the restricting position X, the meshing between the idle gear and the door side gear 42 is disengaged, and the power is transmitted from the power transmission state. Switch to non-transmission state.

<Link mechanism>
Then, the link mechanism 20 which transmits the motive power output from the drive mechanism 10 mentioned above to the door D is demonstrated.

  The link mechanism 20 has one end connected to the output shaft of the drive mechanism 10 (in this embodiment, the output shaft of the door side gear 42) and the other end connected to the door D. Specifically, as shown in FIGS. 29 and 30, the first arm 21 is rotated by the power of the drive mechanism 10 and the second arm 22 is moved in conjunction with the rotation of the first arm 21. .

One end of the first arm 21 is fixed to the door side gear 42 with, for example, a screw, and the other end is connected to the second arm 22, and the rotation axis of the door side gear 42 is interlocked with the door side gear 42. It is comprised so that it may rotate around.
In the present embodiment, the first extending direction L <b> 1 from the one end portion of the first arm 21 toward the other end portion is set to face the rear of the housing H in a state where the door D is closed.

One end portion of the second arm 22 is connected to the first arm 21, and the second arm 22 rotates around the connection portion 23 and moves forward and backward along the second extending direction L <b> 2 from the one end portion toward the other end portion. It is configured as follows.
More specifically, the second arm 22 has a force point for receiving a force from the first arm 21 and an action point for applying a force to the door D, and opens and closes the door D while rotating and moving back and forth.
In the present embodiment, the second extending direction L2 is set to face the front of the housing H when the door D is closed in FIG.

  Here, in the present embodiment, the first extending direction L1 is a direction from the rotation axis of the door side gear 42 toward the rotation axis of the second arm 22 provided at the other end of the first arm 21. Further, the second extending direction L2 is a direction from the force point toward the action point, and specifically, from the rotation axis of the second arm 22 provided at the other end of the first arm 21 to the second arm. It is a direction which goes to the connection part connected to the door D provided in the other end part.

  As shown in FIG. 30, the link mechanism 20 of the present embodiment rotates the door D more than the direction in which the action point is perpendicular to the door D when viewed from the power point when the door D is closed. It is comprised so that it may be located in the axial side (in this embodiment, the hinge Z side).

  In the link mechanism 20 of the present embodiment, the angle formed by the first arm 21 and the second arm 22, that is, the angle θ2 formed by the first extending direction L1 and the second extending direction L2 is 180 degrees in a state where the door D is open. It is comprised so that it may become the following.

<Auxiliary mechanism>
The refrigerator door opening / closing mechanism 100 of the present embodiment further includes an auxiliary mechanism 30 that assists when the above-described link mechanism 20 opens the door D.

The auxiliary mechanism 30 generates an auxiliary force for opening the door D. Here, the auxiliary mechanism 30 is accommodated in a casing (not shown) and attached to the upper surface of the door D.
Specifically, as shown in FIG. 30, this is a rotating member 31 that rotates about a predetermined rotation axis T <b> 1 and an auxiliary force that applies the auxiliary force to the door D by applying a force to the housing H. The applying member 32 includes a connecting member 33 that connects the rotating member 31 and the auxiliary force applying member 32.

The rotating member 31 includes a rotating body 311 and a protruding portion 312 that protrudes upward from the rotating body 311. In this embodiment, the second arm 22 described above contacts the protruding portion 312. The rotating body 311 is configured to rotate around the rotation axis T1.
More specifically, as shown in FIGS. 29 and 30, the second arm 22 of the present embodiment has a long hole 22h penetrating in the thickness direction at the other end, and the long hole 22h has a door. A protruding pin P standing from the upper surface of D is configured to pass through. The second arm 22 has an extending portion 221 that is formed on one end side from the elongated hole 22h and extends in a direction intersecting the second extending direction L2.
With the above-described configuration, the second arm 22 of the present embodiment moves forward and backward along the second extending direction L2 so that the long hole 22h slides along the protruding pin P, and moves from one end to the other end. When moving forward and backward, the extending portion 221 collides with the protrusion 312 of the rotating body 311 to rotate the rotating body 311.

The auxiliary force applying member 32 rotates around the rotation axis T2 in conjunction with the rotating member 31, and has a collision portion 321 that collides with the front surface of the housing H by this rotation.
In the auxiliary force applying member 32 of the present embodiment, the collision portion 321 is provided at a position away from the rotation axis T3 of the door D by a predetermined distance, and the auxiliary force having a magnitude corresponding to the predetermined distance is applied to the door D. It is comprised so that it may act.

  The connecting member 33 connects the rotating member 31 and the auxiliary force applying member 32 and rotates them in conjunction with each other, and has a long shape extending along the longitudinal direction of the door D.

<Control unit>
Next, the control part which controls operation | movement of the door opening / closing mechanism 100 for refrigerators is demonstrated.

  The control unit controls the opening / closing movement of the door D and the operation of the power transmission mechanism 40, and physically includes a CPU, a memory, a timer, an A / D converter, a D / A converter, and the like. Functionally, as shown in FIG. 31, a switching unit 71 that switches the power transmission mechanism 40 to a power transmission state or a power non-transmission state, a speed calculation unit 72 that calculates the moving speed of the door D, and a motor M And a motor control unit 73 for controlling the output.

  Hereinafter, each part will be described.

  The switching unit 71 acquires a switching signal input by the user using, for example, an input unit provided on the door D. Specifically, the voltage applied to the motor M based on the switching signal. Or the voltage applied to the solenoid of the restriction release mechanism 63 is controlled to switch the power transmission mechanism 40 to a power transmission state or a power non-transmission state.

The speed calculation unit 72 calculates the moving speed of the door D based on the moving amount and moving time of the door D.
The speed calculation unit 72 of the present embodiment acquires an opening signal indicating the opening degree of the door from the door opening degree detection mechanism E that detects the opening degree of the door D, and calculates the movement time of the door D from a timer built in the CPU. The time signal shown is acquired, and the moving speed calculated based on each of these signals is output to the motor control unit 73 described later as the calculated speed.

In the present embodiment, as shown in FIG. 28, the door opening degree detection mechanism E is attached to the door side gear 42 via a gear, and the pulse signal corresponding to the rotation amount of the door side gear 42 is opened. This is output to the speed calculation unit 72 as a degree signal. Specifically, an encoder that rotates in synchronization with the door-side gear 42 is used.
The timer measures the time during which the pulse signal is output from the door opening degree detection mechanism E, and outputs the time signal to the speed calculation unit 72 with this time as the movement time of the door D.

  The motor control unit 73 obtains the calculated speed output from the speed calculating unit 72 and a target speed stored in advance in a predetermined area of the memory, for example, and compares the calculated speed with the target speed, The motor speed is variably controlled by PWM control or the like of the output to the motor M so that the calculated speed of the door D approaches the target speed.

  In this embodiment, the speed calculation unit 72 calculates the movement speed for each of a plurality of steps obtained by dividing the movement range of the door D, and the motor control unit 73 is calculated by the speed calculation unit 72 in one step. Based on the calculated speed, the output of the motor M in the next step is controlled.

Here, the movement range of the door D is set to a range from the state in which the door D is closed to the opening degree of the door D reaching a predetermined target angle. The degree is in the range of 0 to 110 degrees.
In addition, each step is set to each range obtained by dividing the above-described movement range for each fixed opening, and in this embodiment, the movement range of 0 to 110 degrees is divided, for example, every 10 degrees. Each range.

  Hereinafter, specific control contents of the control unit in the above-described setting will be described.

  In this embodiment, after the energization of the motor M is started, the door opening detection mechanism E detects the opening of the door D, and the timer determines the time until the opening of the door D increases by 10 degrees. taking measurement.

  Then, based on the opening signal from the door opening detection mechanism E and the time signal from the timer, the speed calculation unit 72 calculates the moving speed while the opening of the door D increases by 10 degrees, that is, the moving speed of each step. The calculation result is output to the motor control unit 73 as a calculation speed.

The motor control unit 73 compares the calculated speed calculated in each step with the target speed set in each step, and outputs the output to the motor M in the next step according to the difference between them. Control is performed by changing the energization ratio (duty ratio) of the control.
More specifically, the motor control unit 73 controls the operation of the motor M to the normal rotation state, the brake state, the OFF state, and the reverse rotation state by switching the four switches SW as shown in FIG. For example, the motor M can be decelerated by switching the forward rotation state or reverse rotation state and the brake state or OFF state in a short time by PWM control. Each switch SW is constituted by a transistor, for example.

According to the control described above, in this embodiment, after the door D starts to open, the door D is moved at a target speed of, for example, 20 to 40 [degrees / second], and then decelerated toward the target angle of 110 degrees. Can be made.
Thereby, regardless of the load applied to the door D, the door D can be automatically opened and closed stably, and the moving speed and the opening degree of the door D can be made uniform.

  According to the refrigerator door opening / closing mechanism 100 according to the present embodiment configured as described above, the swing mechanism 50 moves the pair of idle gears 44 along a plane perpendicular to the rotation axis of the center gear 43, thereby The transmission state and the power non-transmission state can be switched, and a mechanism for moving the gear in the height direction as in the conventional clutch mechanism can be eliminated, and the power transmission mechanism 40 is compact in the height direction. Can be.

  Further, since the pair of idle gears 44 move along a plane perpendicular to the rotation axis of the center gear 43 in conjunction with the rotation of the center gear 43, the idle gear 44 can be moved using the power of the motor M. Thus, a dedicated actuator for moving the idle gear 44 can be eliminated.

  Furthermore, since the solenoid is instantaneously energized to switch from the power non-transmission state to the power transmission state, the configuration of the restriction release mechanism 63 can be simplified and less energy is required for the above-described switching.

  In addition, in the state where the door D is closed, the operating point of the second arm 22 is located closer to the rotation axis of the door D than the direction perpendicular to the door D when viewed from the power point. Without increasing the length of the arms 21 and 22, the door D can be opened and closed by 90 degrees or more.

  In addition, when the door D and the housing H are magnetized with a magnet or the like, when the door D is opened, a force to remove the magnetism is required. However, the auxiliary mechanism 30 has an auxiliary force to open the door D. Since it is generated, magnetization can be removed by this auxiliary force, and thus the power of the motor M required to open the door D can be further reduced. Also, by providing the second arm 22 with the elongated hole 22h, the starting torque that is most loaded on the motor M can be reduced by removing the magnetization while the elongated hole 22h moves along the protruding pin P. The load on the motor M can be reduced.

  The gears are arranged so that the angle between the door gear 42, one or the other idler gear 44 meshing with the door gear 42, and the center gear 43 is 110 degrees or more and 120 degrees or less. Therefore, power can be reliably transmitted without causing hunting or the like.

In addition, since the control unit (not shown) controls the operation speed of the door D to a predetermined speed, the opening / closing speed of the door D is too high even when the weight of the door D varies due to the weight of the contents. Or it is not too late and the operability is good for the user.
More specifically, regardless of the load applied to the door D, the door D can be moved at 20 to 40 [degrees / second], which is an ideal moving speed in terms of user operability, and the opening degree of the door D Can be decelerated aiming at the target angle of 110 degrees, and the moving speed and opening degree of the door D can be made uniform.

  Furthermore, since the angle restricting portion 515 restricts the angle formed by the rotation shafts of the respective idle gears around the rotation axis of the center gear 43 to a predetermined angle or less, both the pair of idle gears 44 are the door side gear 42. Can be prevented from meshing with each other.

<Modification of Fourth Embodiment>
The present invention is not limited to the above embodiment.

  For example, in the above embodiment, the rotational load member is an elastic member. However, for example, the rotational load member may be one that causes friction between the idle gear and the mounting member. Examples thereof include a sheet member and a magnetic resistance such as a magnet.

  Moreover, in the said embodiment, although each idle gear was attached to another attachment member, a pair of idle gear may be attached to the common attachment member.

  Furthermore, in the said embodiment, although the door side gear was one, you may have a some door side gear.

  In addition, although the power transmission mechanism of the embodiment has been used to open and close the refrigerator door, it is not necessarily limited to the refrigerator door.

  In addition, in the control of the embodiment, the door movement range is 0 to 110 degrees, and each step is a range obtained by dividing the movement range every 10 degrees. However, the movement range and the setting of each step are appropriately changed. It doesn't matter.

  In addition, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

<Fifth Embodiment>
Below, the door opening / closing mechanism 100 for refrigerators in 5th Embodiment is demonstrated with reference to FIGS. In addition, the same code | symbol shall be attached | subjected to the same member as the said 1st Embodiment.

  The refrigerator door opening / closing mechanism 100 of the present embodiment moves the power transmission mechanism 40 that transmits the power of the motor M to the hinge Z of the door only by the rotation of the plurality of drive gears 45 and the door D at the closed position in the opening direction. And an auxiliary mechanism 30 that generates an auxiliary force for the purpose.

  Further, the refrigerator door opening / closing mechanism 100 is a power transmission that changes (switches) between a power transmission state in which the power of the motor M is transmitted to the hinge Z and a power non-transmission state in which the power of the motor M is not transmitted to the hinge Z. A state transition mechanism (power transmission state / non-transmission state switching mechanism) 101 is provided.

  The power transmission state transition mechanism 101 is interposed between the motor M and the hinge Z as shown in FIGS. Here, a plurality of door-side gears 42 are interposed between the toothless gear 46 connected to the hinge Z and the power transmission state transition mechanism 101, but one door-side gear 42 is interposed between them. It may be interposed. Further, the missing tooth gear 46 connected to the hinge Z may have teeth on the entire circumference. The missing gear 46 in this embodiment does not rotate as in the first embodiment, but is fixed to the hinge Z and is a part of the drive gear 45.

  Specifically, as shown in FIGS. 35 and 36, the power transmission state transition mechanism 101 includes a center gear 43 connected to the motor side gear 41, a pair of idle gears 44 that mesh with the center gear 43, and a pair of idle gears. And a swing mechanism 50 that rotates the shaft 44 around the rotation axis of the center gear.

  As in the first embodiment, the swing mechanism 50 rotates around the rotation shaft of the center gear 43 and has a first attachment member 51 to which the idle gear 44 is attached, and the first attachment member 51 and the idle gear 44. And a rotation load member 52 that applies a load to the rotation of each idle gear 44, and in this embodiment, further includes a second attachment member 54 to which the center gear 43 is attached.

  The first mounting member 51 has a pair of idle gear mounting shafts 512 and has a flat plate shape in which a through hole 516 is formed.

  The rotation load member 52 applies a load to the rotation of the idle gear 44 and generates a torque for turning the pair of idle gears 44 around the rotation axis of the center gear 43. Here, the rotation gear 52 is applied to the idle gear mounting shaft 512. An elastic member such as a spring to be passed.

The second mounting member 54 has a flat plate shape on which the center gear mounting shaft 7 is provided, and is disposed below the first mounting member 51.
The second mounting member 54 rotates in conjunction with the center gear 43 and rotates independently of the first mounting member 51.

  In the present embodiment, as shown in FIG. 36, after the first mounting member 51 is placed on the upper surface of the second mounting member 54 by passing the center gear mounting shaft 7 through the through hole 516, the floating gear mounting shaft is mounted. The floating gear 44 is attached to 512 and the center gear 43 is attached to the center gear attachment shaft 7.

In attaching the idle gear 44 to the idle gear mounting shaft 512, the rotary load member 52 is passed through the idle gear mounting shaft 512, the idle gear 44 is passed from above, and a pressing member that presses the idle gear 44 from above. By passing 53, an upward force is applied from the rotary load member 52 to the idle gear.
The pressing member 53 is configured to engage with a concave groove 513 formed along the circumferential direction on the outer peripheral surface of the floating gear mounting shaft 512.

  With the configuration described above, the idle gear 44 moves in conjunction with the motor M between the forward rotation power transmission position, the reverse rotation power transmission position, and the power non-transmission position. Each position and specific operation of the idle gear 44 are the same as those in the first embodiment (see FIG. 4), and are omitted here.

  In this way, the power transmission state transition mechanism 101 changes between the power transmission state and the power non-transmission state by the power while receiving the power of the motor M. More specifically, the swing mechanism 50 turns the pair of idle gears 44 so that one or the other idle gear 44a meshes with the door side gear 42 to enter a power transmission state, and the pair of idle gears 44 and the door By disengaging the side gear 42, the power is not transmitted. That is, the state where the idle gear 44 is in the forward rotation power transmission position or the reverse rotation power transmission position is the power transmission state, and the state where the idle gear 44 is in the power non-transmission position is the power non-transmission state.

  The refrigerator door opening / closing mechanism 100 of the present embodiment is closed by causing the auxiliary mechanism 30 to generate an auxiliary force when the power transmission state transition mechanism 101 is in a power non-transmission state and the power of the motor M is not transmitted to the hinge. The door D in the position is configured to move in the opening direction. As shown in FIG. 34, the auxiliary mechanism 30 includes a slide member 34 and an auxiliary force applying member 32. Since the operation and the like are the same as those in the first embodiment, detailed description thereof is omitted here. To do.

  The refrigerator door opening / closing mechanism 100 of the present embodiment further includes a power non-transmission state holding mechanism 60 and a power conversion mechanism 70 as in the first embodiment. In the present embodiment, these mechanisms 60 and 70 and the configuration related to them are different from the above-described embodiments and are characteristic, and will be described in detail below.

First, the power conversion mechanism 70 will be described.
As shown in FIG. 37, the power conversion mechanism 70 is interposed between the slide member 34 and the drive gear 45, and converts the rotational power of the drive gear 45 into the slide power of the slide member 34. It is.

  When the motor M rotates in the reverse direction and moves the door D in the closing direction, the power conversion mechanism 70 does not transmit the power of the motor M to the auxiliary mechanism 30 and the motor M rotates in the forward direction. When moving in the opening direction, a ratchet mechanism 102 for transmitting the power of the motor M to the auxiliary mechanism 30 is provided.

  The ratchet mechanism 102 includes a ratchet 71 (claw portion 71 in the first embodiment) attached to the slide member 34, and a pressing portion 72 (projection portion 72 in the first embodiment) that rotates in conjunction with the drive gear 45. And have.

  As shown in FIGS. 38 and 39, the ratchet 71 is provided at the other end 342 of the slide member 34, and a pressed end surface 711 that is pressed by the pressing portion 72 when the motor M rotates forward. The guide surface 712 guides the movement of the pressing portion 72 when the motor M rotates in the reverse direction.

  As shown in FIG. 39, the ratchet 71 is configured to be able to move between a normal posture N in a state where no external force is applied and a rotation posture R rotated from the normal posture N around the rotation shaft 7T. And has an elastic portion 713 that generates an urging force toward the normal posture N in the rotational posture R. Here, the rotation posture R is a state in which the rotation posture R is rotated from the normal posture N in a direction away from the rotation shaft of the center gear 43.

  The ratchet 71 of the present embodiment is located below the second mounting member 54 described above, and the pressed end surface 711 and the guide surface 712 are positioned on the rotation track of the pressing portion 72 in the normal posture N state. Are arranged as follows.

  As shown in FIG. 37, the pressing portion 72 rotates in conjunction with the center gear 43 and applies power in the sliding direction of the sliding member 34 to the ratchet 71. Specifically, the pressing portion 72 has a plurality of protrusions provided on the second mounting member 54. In this embodiment, the two pressing portions 72 are provided on the back surface of the second mounting member 54. Note that the number of the pressing portions 72 may be changed as appropriate, for example, one.

Next, the power non-transmission state holding mechanism 60 will be described.
The power non-transmission state holding mechanism 60 regulates the turning of the swing mechanism 50 and holds the power non-transmission state without engaging each of the idle gears 44 with the door side gear 42. 37, a contact portion 64 provided on the first mounting member 51 and rotating together with the first mounting member 51, and a target to which the contact portion 64 contacts to regulate the turning of the swing mechanism 50. A contact portion 65.

  As shown in FIG. 40, the abutting portions 64 are protrusions provided on the back surface of the first mounting member 51, and here, the pair of abutting portions 64 are on the respective rotation axes of the idle gears 44. Is provided. The protruding lengths of the contact portions 64 are set to dimensions that do not contact the pressed end surface 711 of the ratchet 71, that is, dimensions that do not allow the tip of the contact portion 64 to reach the upper surface 714 of the ratchet 71. That is, the contact portion 64 is located above the upper surface 714 of the ratchet 71.

  The power non-transmission state needs to be maintained until the door D and the housing H are demagnetized when the door D in the closed position is moved in the opening direction. When the door D is moved in the opening direction, it may be provided on the side of the idle gear 44 (the upper idle gear 44 in FIG. 37) that does not mesh with the door side gear 42. On the other hand, in the present embodiment, the pair of contact portions 64 is provided on the first mounting member 51 without worrying about the direction of the first mounting member 51 when assembling the members. This is because the work can be advanced and the manufacture can be easily performed.

The contacted portion 65 is configured such that when the motor M rotates in the forward direction and the pair of idler gears 44 moves toward the positive rotation power transmission position as the first mounting member 51 rotates, the pair of idler gears 44 move in the normal rotation power. The contact portion 64 is provided at a position where the contact portion 64 contacts before reaching the transmission position.
Specifically, as shown in FIGS. 38 and 39, the abutted portion 65 is located above the upper surface 714 of the ratchet 71, and here, a rib provided upright from the upper surface 714 of the ratchet 71. It is of shape. The contacted portion 651 has a contacted surface 651 with which the contact portion 64 contacts.

  Next, operations of the power non-transmission state holding mechanism 60 and the power conversion mechanism 70 configured as described above will be described with reference to FIGS.

First, the case where the door D in the closed position is moved in the opening direction will be described.
When the motor M is rotated forward with the door D in the closed position, as shown in FIG. 41 (a), the swing mechanism 50 causes the pair of idle gears 44 to be powered off in conjunction with the rotation of the center gear 43. Turn from the transmission position to the forward rotational power transmission position. Since the first mounting member 51 rotates in conjunction with the turning, the contact portion 64 provided on the first member 51 rotates toward the contacted portion 65.

  As shown in FIG. 41 (b), when the contact portion 64 contacts the contacted portion 65 (specifically, the contacted surface 651), the rotation of the first mounting member 51, that is, the idle gear. 44 is restricted from turning and the power non-transmission state is maintained. The reason why the turning of the idle gear 44 is restricted is that the idle gear 44 is turned by a relatively small torque due to the load of the rotary load member 52.

  From this state, when the motor M further rotates forward, the second mounting member 54 rotates independently of the first mounting member 51. Therefore, as shown in FIG. 2 The pressing part 72 provided on the attachment member 54 rotates, and any one pressing part 72 hits the ratchet 71 (specifically, the pressed end surface 711).

  Further, when the motor M rotates forward, the pressing portion 72 presses the ratchet 71 via the pressed end surface 711 and the power in the rotation direction of the center gear 43 is transmitted via the ratchet 71 as shown in FIG. Then, it is transmitted to the slide member 34 as power in the sliding direction, and the slide member 34 slides.

  As a result, the door D and the housing H are demagnetized by the auxiliary force of the auxiliary mechanism 30, and the door D in the closed position starts to move in the opening direction.

Next, the case where the door D in the open state is moved in the closing direction will be described.
When the motor M is rotated in the reverse direction with the door D opened, the second mounting member 54 rotates in conjunction with the center gear 43 as shown in FIG. It rotates toward the ratchet 71 (specifically, the guide surface 712).

  When the motor M further rotates reversely after the pressing portion 72 hits the guide surface 712, as shown in FIG. 43 (f), the pressing portion 72 rotates while pressing the guide surface 712, and the ratchet 71 is rotated around the rotation axis 7T. Rotate. As a result, the ratchet 71 rotates from the normal posture N to the rotational posture R and moves so as to retract from the pressing portion 72.

  As a result, when the motor M rotates in the reverse direction, the pressing portion 72 continues to rotate without being disturbed by the ratchet 71, and the door D moves in the closing direction.

Incidentally, when the door D is moved in the opening direction, the ratchet 71 moves from the standby position A to the pushing position B as the slide member 34 slides as shown in FIG.
Here, the standby position A is a position of the ratchet 71 immediately before the pressing portion 72 presses the pressed end surface 711 when the motor M rotates forward. The pushing position B is the position of the ratchet 71 immediately before the pressing portion 72 that presses the pressed end surface 711 by the motor M rotating forward is separated from the pressed end surface 711.

  From this, when the ratchet 71 is pressed by the pressing portion 72, that is, when the ratchet 71 remains in the push-in position B, the slide member 34 and the like are moved from the user when the door D is moved in the opening direction. It looks and looks bad.

  Therefore, the auxiliary mechanism 30 according to the present embodiment includes a pull-back member (not shown) that pulls back the slide member 34 that has been slid and moved by the pressing portion 72 pressing the ratchet 71. Specifically, the pull-back member is for pulling back the ratchet 71 from the push-in position B to the standby position A by urging the slide member 34 in the direction opposite to the slide direction. It is an elastic member.

  However, if the pullback member is simply provided, when the pullback member pulls back the slide member 34, the ratchet 71 moves from the push-in position B to the standby position A while maintaining the normal posture N. The ratchet 71 is pressed, and the slide member 34 slides again. In other words, the provision of the pull-back member only repeats that the slide member 34 is slid and moved back when the door D is moved in the opening direction, and the appearance can be sufficiently improved. That's not true.

  Therefore, in the present embodiment, as shown in FIGS. 38 to 40, when the slide member 34 is pulled back by the pullback member to the ratchet 71 described above, the pressed surface 652 (hereinafter referred to as “pressed surface”) pressed by the contact portion 72. (Also referred to as a pressed slide surface 652).

  The pressed slide surface 652 is provided in the contacted portion 65 described above, and specifically, is formed continuously from the side of the pressed end surface 651 on the first mounting member 51 side. In this embodiment, the pressed slide surface 652 is curved in a direction away from the rotation axis of the center gear 43, and the contact portion 64 slides on the pressed slide surface 652 so that the contact portion 64 is covered. The ratchet 71 is pressed via the pressing slide surface 652 to move from the normal posture N to the rotational posture R.

  44 (a) and 44 (b), the slide member 34 is pulled back by a pull-back member (not shown) to move the ratchet 71 from the push-in position B to the standby position A, as shown in FIGS. The pressed slide surface 652 hits the contact portion 64.

  Then, as shown in FIGS. 44B and 44C, the ratchet 71 further moves toward the standby position A, so that the pressed slide surface 652 moves so as to slide with respect to the contact portion 64. The abutting portion 64 presses the ratchet 71 via the pressed slide surface 652. Accordingly, the ratchet 71 rotates from the normal posture N to the rotation posture R while moving from the push-in position B to the standby position A.

  As a result, the rotation posture R is maintained after the ratchet 71 moves to the standby position A, so that the ratchet 71 does not interfere with the pressing portion 72 and is not pressed by the pressing portion 72. Thereby, after the slide member 34 is pulled back, it can be prevented from sliding again, and the appearance can be improved.

  As described above, according to the refrigerator door opening / closing mechanism 100 according to the present embodiment, the power transmission state transition mechanism 101 is in the power non-transmission state, and the motor M is closed in a state where the power of the motor M is not transmitted to the hinge Z. Since the door D at the position is moved in the opening direction by the assisting force, the torque of the motor M required to demagnetize the door D and the housing H can be reduced, and the motor M can be downsized. .

  Furthermore, since the power of the motor M is transmitted to the hinge Z and the auxiliary mechanism 30 only by mechanical parts such as gears, the door D can be automatically opened and closed without using electric parts such as switching elements.

  In addition, since the power conversion mechanism 70 includes the ratchet mechanism 102, when the door D in the closed position is moved in the opening direction, an auxiliary force is generated and the door D is moved in the closing direction. The power conversion mechanism 70 can prevent the movement of the door D from being hindered.

  In addition, since the slide member 34 that has been slid when the magnetization is removed is pulled back by the pull-back member, the slide member 34 can be hidden from the user while the door is moved in the opening direction. Does not cause any deterioration.

  In addition, when the slide member 34 is pulled back, the ratchet 71 is rotated from the normal posture N to the rotary posture R to avoid interference between the ratchet 71 and the pressing portion 72. It is possible to prevent 34 from sliding again.

<Modification of Fifth Embodiment>
As another embodiment for moving the door in the closed position in the opening direction by the auxiliary force in a state where the power of the motor is not transmitted to the hinge, as shown in FIG. 45, a pressing portion constituting the power conversion mechanism 70 The structure which increased the number of 72 can be considered (here, the five press parts 72 are illustrated).

  With such a configuration, it is possible to shorten the time until one of the pressing portions 72 hits the ratchet 71 as compared to the case where there are two or one pressing portion 72 as in the fifth embodiment. . Thus, when the motor M is rotated forward, the ratchet 71 is moved by the pressing portion 72 before the idle gear 44 in the power non-transmission position moves to the positive rotation power transmission position, that is, before meshing with the door side gear 42. It is possible to generate an auxiliary force in a state where the possibility of pressing is high and the power of the motor M is not transmitted to the hinge Z.

  However, even if the number of the pressing portions 72 is increased in this way, the idle gear 44 may mesh with the door side gear 42 before the pressing portion 72 presses the ratchet 71, and the power of the motor M is hinged. In order to generate the auxiliary force more reliably in a state where it is not transmitted to Z, a configuration including the power non-transmission state holding mechanism 60 as in the fifth embodiment is preferable.

  Further, when the number of the pressing portions 72 is increased, the probability that the ratchet 71 that moves from the pushing position B to the standby position A hits the pressing portion 72 when the slide member 34 that has been slid back is pulled back increases. It is not possible to pull back. Even in view of this point, the configuration of the fifth embodiment is preferable.

  In addition, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 100 ... Refrigerator door opening / closing mechanism R ... Refrigerator D ... Door Z ... Hinge axis | shaft M ... Motor 10 ... Drive mechanism 30 ... Auxiliary mechanism 40 ... Power transmission mechanism 41・ ・ ・ Motor side gear 42 ・ ・ ・ Door side gear 43 ・ ・ ・ Center gear 44 ・ ・ ・ idle gear 45 ・ ・ ・ drive gear 46 ・ ・ ・ missing gear 50 ・ ・ ・ head swing mechanism 60 ・ ・ ・ power Non-transmission state holding mechanism 80... Missing gear rotation mechanism

Claims (33)

A motor that outputs power to open and close the door;
A power transmission mechanism for transmitting the power of the motor to the hinge by rotation of a plurality of drive gears;
An auxiliary mechanism for generating an auxiliary force for moving the door in the closed position in the opening direction,
The refrigerator door characterized in that the auxiliary force is generated in the auxiliary mechanism by the power of the motor before the power of the motor is transmitted to the hinge through the power transmission mechanism. Opening and closing mechanism.   The power transmission state transition mechanism that changes between a power transmission state in which the power of the motor is transmitted to the hinge and a power non-transmission state in which the power of the motor is not transmitted to the hinge is further provided. The door opening / closing mechanism for refrigerators according to 1. The drive gear includes a door-side gear that rotates in conjunction with opening and closing of the door, a motor-side gear that rotates in conjunction with the motor, a center gear connected to the motor-side gear, and the center gear And a pair of idler gears that maintain a predetermined relative position.
The power transmission state transition mechanism has a swing mechanism that rotates together with the pair of idle gears around a rotation axis of the center gear in conjunction with forward rotation or reverse rotation of the center gear. The door opening / closing mechanism for a refrigerator according to claim 2.   As the pair of idle gears pivots the swing mechanism, a positive rotational power transmission position where one idle gear meshes with the door side gear and moves the door in the opening direction, and the other idle gear is the It moves between a reverse rotation power transmission position that meshes with the door side gear and moves the door in the closing direction, and a power non-transmission position where none of the pair of idle gears meshes with the door side gear. The door opening and closing mechanism for a refrigerator according to claim 3. The swing mechanism is
The floating gear is attached, and an attachment member that rotates around a rotation axis of the center gear;
5. The refrigerator door opening and closing according to claim 3, further comprising a rotation load member that is interposed between the attachment member and the idle gear and that applies a load to the rotation of each idle gear. mechanism.   2. A power non-transmission state holding mechanism that restricts the swing of the swing mechanism and maintains the power non-transmission state without engaging each of the idle gears with the door-side gear. The door opening / closing mechanism for refrigerators as described in any one of 3 thru | or 5. The power non-transmission state holding mechanism is
A contact portion provided on the mounting member and rotating together with the mounting member;
When the pair of idler gears move toward the positive rotational power transmission position as the mounting member rotates, the contact portion abuts before the pair of idler gears reaches the positive rotational power transmission position. The door opening / closing mechanism for a refrigerator according to claim 6, further comprising a contacted portion that restricts turning of the swing mechanism. The auxiliary mechanism is
A slide member provided at an upper portion of the door and slidable in conjunction with rotation of the drive gear;
An auxiliary force applying member that is provided so as to be rotatable around a predetermined rotation axis in conjunction with the sliding movement of the slide member, and that contacts the housing by rotating around the rotation axis and applies the auxiliary force to the door. The door opening and closing mechanism for a refrigerator according to any one of claims 1 to 7, characterized by comprising:   9. A power conversion mechanism that is interposed between the slide member and the drive gear and converts power in the rotational direction of the drive gear into power in the slide direction of the slide member. The door opening / closing mechanism for refrigerators as described. The power conversion mechanism is
When the motor rotates in the reverse direction and moves the door in the closing direction, when the motor rotates in the forward direction and moves the door in the opening direction without transmitting the power of the motor to the auxiliary mechanism. The refrigerator door opening / closing mechanism according to claim 9, further comprising a ratchet mechanism that transmits power of the motor to the auxiliary mechanism. The ratchet mechanism is
A ratchet attached to the slide member;
A pressing portion that rotates in conjunction with the drive gear;
When the motor rotates in the forward direction, the slide member slides by the pressing portion contacting and pressing the ratchet, and when the motor rotates in the reverse direction, the pressing portion comes into contact. The door opening / closing mechanism for a refrigerator according to claim 10, wherein the sliding member does not slide by the escape of the ratchet. The ratchet according to claim 11 has the abutted portion according to claim 7,
When the motor rotates forward in a state where the door is in the closed position, the abutting portion according to claim 7 abuts against the abutted portion and the swinging mechanism is restricted from turning, and then the claim 11. When the pressing part presses the ratchet, the sliding member slides and the door moves in the opening direction by the auxiliary force. The auxiliary mechanism has a pull-back member that pulls back the slide member moved by the pressing portion pressing the ratchet,
The ratchet has a pressed surface that is pressed by the contact portion when the slide member is pulled back by the pull-back member;
The contact portion presses the pressed surface, so that the ratchet moves away from the pressing portion, and then the pressing portion rotates without interfering with the ratchet. 12. The refrigerator door opening and closing mechanism according to 12. A toothless gear that is attached to a hinge shaft of a hinge that rotatably supports the door and rotates about the hinge shaft;
A non-tooth gear rotation mechanism for rotating the non-tooth gear between a contact position in contact with the drive gear and a non-contact position not in contact with the drive gear in conjunction with the opening and closing movement of the door; ,
When the toothless gear rotation mechanism holds the toothless gear in the non-contact position in a state where the door is in the closed position, and the door in the closed position moves in the opening direction by the auxiliary force, this movement The refrigerator door opening / closing mechanism according to claim 1, wherein the toothless gear is rotated and moved from the non-contact position to the contact position in conjunction with the movement of the refrigerator.   The door opening / closing mechanism for a refrigerator according to claim 14, wherein the drive gear that meshes with the toothless gear has teeth on the entire circumference.   The refrigerator door opening / closing mechanism according to claim 14 or 15, wherein the motor is provided on an upper portion of the door. The toothless gear rotation mechanism,
A missing gear biasing member that biases the missing gear from the non-contact position toward the contact position;
A rotating member that is rotatably provided around a rotation axis, and is rotated against the non-tooth gear by rotating around the rotation axis to rotate the non-tooth gear from the contact position to the non-contact position; The refrigerator door opening / closing mechanism according to any one of claims 14 to 16, wherein the refrigerator door opening / closing mechanism is provided. The toothless gear rotation mechanism,
A link member connected to the toothless gear and moving between a contact position contacting a contacted portion fixed to the housing side and a separated position spaced apart from the contacted portion by a magnetic force; ,
A regulating member that is provided on the door side and that contacts the link member and regulates the movement of the link member in a state where the door is in the closed position;
When the door is in the closed position, the restriction member keeps the link member at one of the contact position or the separation position, and the door moves in the opening direction by the auxiliary force, the restriction member is moved to the link. The link member is moved in a direction away from the member, and the link member is moved to the other of the contact position or the separation position by a magnetic force, and the missing gear is moved from the non-contact position to the contact position. The door opening / closing mechanism for refrigerators as described in any one of Claims 14 thru | or 16. The contacted portion is a hinge plate attached to the housing;
The link member has a magnet that contacts the hinge plate in the state of the contact position,
19. The refrigerator door opening / closing mechanism according to claim 18, wherein the toothless gear moves from the non-contact position to the contact position when the link member moves from the separated position to the contact position. The drive gear includes a door-side gear that rotates in conjunction with opening and closing of the door, a motor-side gear that rotates in conjunction with the motor, a center gear connected to the motor-side gear, and the center gear And a pair of idler gears that maintain a predetermined relative position.
In conjunction with forward rotation or reverse rotation of the center gear, further comprising a swing mechanism that pivots with the pair of idle gears around the rotation axis of the center gear,
As the swing mechanism swings, the pair of idle gears has a positive rotational power transmission position where one idle gear meshes with the door side gear, and a reverse rotational power transmission position where the other idle gear meshes with the door side gear. The door opening and closing for the refrigerator according to any one of claims 14 to 19, wherein both of the pair of idle gears move between a power non-transmission position where the pair of idle gears do not mesh with the door side gear. mechanism.   A power non-transmission state holding mechanism that restricts the movement of the pair of idle gears by the swing mechanism so that none of the idle gears meshes with the door side gear. The door opening and closing mechanism for a refrigerator according to claim 20. The swing mechanism has an attachment member to which the idle gear is attached and which rotates around a rotation shaft of the motor side gear,
The power non-transmission state holding mechanism has an idle gear biasing member that biases the mounting member to an intermediate position where the pair of idle gears are held at the power non-transmission position,
When the motor stops, the idle gear biasing member biases the attachment member to the intermediate position, and the pair of idle gears moves to the power non-transmission position,
When the motor is driven, the pair of idle gears rotate against the urging force of the idle gear urging member, and the pair of idle gears move to the normal rotation power transmission position or the reverse rotation power transmission position. The refrigerator door opening and closing mechanism according to claim 21. The swing mechanism is
23. The refrigerator door opening / closing mechanism according to claim 22, further comprising a rotation load member that is interposed between the attachment member and the idle gear and that applies a load to the rotation of each idle gear.   24. The angle formed by the door-side gear, the idler gear meshing with the door-side gear, and the motor-side gear is 90 degrees or more and 130 degrees or less. The door opening / closing mechanism for refrigerators as described in the item. The auxiliary mechanism is
A slide member provided from one end side to the other end side in the upper part of the door, and slidable in conjunction with rotation of the drive gear;
An auxiliary force applying member that is provided so as to be rotatable around a predetermined rotation axis in conjunction with the sliding movement of the slide member, and that contacts the housing by rotating around the rotation axis and applies the auxiliary force to the door. The door opening / closing mechanism for a refrigerator according to any one of claims 14 to 24, wherein:   When the drive gear that has meshed with the missing gear disengages from the missing gear due to movement of the door in the opening direction, the disengaged drive gear is re-engaged with the missing gear. The refrigerator door opening / closing mechanism according to any one of claims 14 to 25, further comprising a return mechanism for moving the door in the closing direction. The return mechanism is
A flexible member having an elastic force; and a contact member that is bent in contact with the flexible member;
One of the bending member and the contact member rotates integrally with the door, and the other is fixed.
The bending member and the contact member come into contact with each other when the door moves in the opening direction, the bending member bends, and the door is moved in the closing direction by its restoring force. The refrigerator door opening and closing mechanism according to claim 26. The flexible member is provided to move along a contact surface formed on the contact member;
The contact surface is in contact with a rotation locus of a contact point of the bending member with the contact member and passes through a tangent passing through the rotation center of the bending member, and a degree of bending of the bending member determined in advance around the bending member. 28. The refrigerator door opening / closing mechanism according to claim 27, wherein an angle formed between a virtual circle drawn in a straight line and a straight line passing through an intersection of the tangent is 30 degrees or more and 60 degrees or less.   29. The one of the bending member and the contact member is attached to the lower side of the door, and the other is fixed to the lower side of the hinge shaft or the lower side of the casing. Door opening and closing mechanism for refrigerators. Further comprising a refrigerator door control device for controlling a motor for moving the door of the refrigerator to automatically move the door;
The refrigerator door control device,
An induced voltage detector for detecting an induced voltage generated when the motor is rotating;
An applied voltage control unit that controls an applied voltage of the motor so that a detected value detected by the induced voltage detecting unit becomes a predetermined target value according to an opening angle of the door; 30. The refrigerator door opening / closing mechanism according to any one of claims 1 to 29. The movement range of the door is divided into a plurality of continuous division ranges,
31. The refrigerator door opening / closing mechanism according to claim 30, wherein the target value is determined for each of the divided ranges. In the state where the door is closed, when the applied voltage for moving the door in the opening direction becomes a predetermined threshold, a zero setting unit that sets the opening angle to zero,
32. The refrigerator door opening / closing mechanism according to claim 30 or 31, further comprising an opening angle detection unit that detects the opening angle from zero opening angle set by the zero setting unit. An encoder or a rotary switch is provided on a drive gear that is interposed between the motor and the door and rotates in conjunction with the motor,
The door opening / closing mechanism for a refrigerator according to claim 32, wherein the opening angle detection unit detects the opening angle based on an output from the encoder or the rotary switch.