Refrigerator

Abstract

To provide a refrigerator having a structure capable of reducing the number of components and manufacturing cost, and performing automatic closing and free stop.SOLUTION: In the refrigerator 1, the plurality of recessed portions 532, 533 are formed in the circumferential surface of less than half the circumference of the cam 53, the heat insulating door 16 is maintained in a state of being opened at a predetermined angle when the leaf spring 55 is engaged with one recessed portion 533, and the heat insulating door 16 is rotated to a state of closing the front opening of the storage compartment when the leaf spring 55 is rotated along the circumferential surface of the cam 53 and the leaf spring 55 is engaged with the other recessed portion 532.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to refrigerators. [Background technology]

[0002] There is known a refrigerator having an insulated door that rotates around a rotation axis supported on an insulated box in which a storage compartment is formed, to open and close the front opening of the storage compartment (see, for example, Patent Documents 1 to 3). The insulated door of the refrigerator has a so-called auto-close structure that automatically closes the door from a state where it is open at an angle smaller than a predetermined angle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4264838 [Patent Document 2] Patent No. 5169706 [Patent Document 3] Japanese Patent Application Laid-Open No. 2008-134002 [Patent Document 4] Patent No. 6145697 Summary of the Invention [Problem to be solved by the invention]

[0004] The refrigerators described in Patent Documents 1 to 3 above are equipped with a structure that performs what is called an auto-close function, but are not capable of performing what is called a free stop, which allows the door to be temporarily maintained open at a predetermined angle. On the other hand, Patent Document 4 above describes a refrigerator equipped with a structure that performs a free stop. If the structure for performing a free stop described in Patent Document 4 is added to the refrigerators described in Patent Documents 1 to 3 above, the configuration becomes complicated, making it difficult to reduce the number of parts and the manufacturing cost.

[0005] The present disclosure aims to provide a refrigerator that has a structure capable of performing auto-close and free stop, while reducing the number of parts and manufacturing costs. [Means for solving the problem]

[0006] (1) The present disclosure relates to a refrigerator comprising an insulated box body having a storage compartment formed therein; an insulated door rotatably supported around a rotation axis supported on the insulated box body and capable of opening and closing a front opening of the storage compartment by rotating around the rotation axis; a hinge attached to the insulated box body and supporting the insulated door; a cam non-rotatably fixed to the hinge and having a recess formed on its circumferential surface; and a leaf spring that rotates along the circumferential surface of the cam while pressing the circumferential surface of the cam so as to be engageable with the recess of the cam, wherein a plurality of the recesses are formed on the circumferential surface of less than half the circumference of the cam, and the insulated door is maintained open at a predetermined angle by engaging one of the recesses with the leaf spring, and the insulated door is rotated to a position that closes the front opening of the storage compartment by rotating the leaf spring along the circumferential surface of the cam and engaging the other of the recesses with the leaf spring.

[0007] According to the refrigerator of (1), a simple configuration using one cam and a leaf spring that moves along the circumferential surface of the cam can achieve not only the auto-close function of the insulated door but also the free stop function. As a result, the refrigerator can be made compact with a reduced number of parts and reduced manufacturing costs.

[0008] (2) The leaf spring is composed of a single C-shaped metal plate with a rectangular central portion, and the one recess and the other recess are formed in pairs at symmetrical positions around the axis of the cam, as described in (1).

[0009] According to the refrigerator of (2), the cam is sandwiched between the leaf springs in the diameter direction of the cam, and the leaf springs can be reliably engaged with the recesses on one side and the recesses on the other side. This allows the auto-close and free-stop functions to be reliably performed.

[0010] (3) The refrigerator described in (2) is provided with a metal leaf spring retaining member that abuts against and surrounds each of a pair of side portions in the center of the leaf spring and a rear wall portion connecting the pair of side portions.

[0011] According to the refrigerator (3), the C-shaped leaf spring can reinforce the force clamping the cam, and the leaf spring can be securely engaged with each of the recesses on one side and the other side.

[0012] (4) The refrigerator described in (3), wherein the cam is supported by being sandwiched between the leaf spring holding member and a metal support member.

[0013] According to the refrigerator (4), the cam is supported by being sandwiched between metal members, which makes it possible to prevent damage to the structure supporting the cam and improve reliability.

[0014] (5) The cam penetrates a through-hole formed in a base member disposed above the support member, thereby engaging with the base member.

[0015] According to the refrigerator (5), the cam engages with the base member, and by making the cam and the base member out of resin or the like, it is possible to suppress abnormal noises when the insulated door is opened and closed.

[0016] (6) The refrigerator according to (4), wherein the support member is a stopper that prevents the insulating door from rotating at a predetermined position.

[0017] According to the refrigerator (6), the cam can be supported by being sandwiched between a high-strength stopper and a leaf spring holding member, which reliably prevents the structure supporting the cam from becoming easily damaged, thereby enabling greater reliability.

[0018] (7) The refrigerator described in (1) in which the depths of the recesses of the cam are different.

[0019] According to the refrigerator (7), the depths of one recess and the other recess of the cam are different. This makes it possible to make it more difficult for the engaging portion of the leaf spring to come off the recess when the leaf spring engages with the deeper recess than when the leaf spring engages with the shallower recess.

[0020] (8) A refrigerator according to (1), wherein the plurality of recesses of the cam in a cross section perpendicular to the axis of the cam each have a different curvature.

[0021] According to the refrigerator of (8), it is possible to configure the recessed portion having an arc shape with a large radius of curvature so that the leaf spring can more easily engage with the recessed portion having an arc shape with a small radius of curvature. [Effects of the Invention]

[0022] According to the present disclosure, it is possible to provide a refrigerator having a structure capable of performing auto-close and free stop, while reducing the number of parts and manufacturing costs. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a perspective view illustrating a refrigerator according to an embodiment of the present disclosure. [Figure 2] 1 is a side cross-sectional view showing an auto-close device of a refrigerator according to an embodiment of the present disclosure. [Figure 3] 1 is a plan view cross-sectional view showing an auto-close device of a refrigerator according to an embodiment of the present disclosure. [Figure 4]1 is an exploded perspective view showing an auto-close device of a refrigerator according to an embodiment of the present disclosure and a portion to which the auto-close device is attached. FIG. [Figure 5] 1 is an exploded perspective view showing an auto-close device of a refrigerator according to an embodiment of the present disclosure. FIG. [Figure 6] FIG. 2 is a plan view showing a cam of an auto-close device of a refrigerator according to an embodiment of the present disclosure. [Figure 7] 10A and 10B are diagrams illustrating a free-stop state in which the insulation door of the refrigerator according to the embodiment of the present disclosure is open. [Figure 8] 1 is a diagram illustrating a state in which an insulating door of a refrigerator according to an embodiment of the present disclosure is closed by auto-close. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0024] A refrigerator according to an embodiment of the present disclosure will be described below with reference to the drawings. In the following description, the widthwise direction of the refrigerator 1, from the lower right to the upper left as shown in FIG. 1, is defined as the leftward direction, and the opposite direction is defined as the rightward direction. The depthwise direction of the refrigerator 1 (from the lower left to the upper right as shown in FIG. 1) is defined as the rearward direction, and the opposite direction is defined as the frontward direction. The heightwise direction of the refrigerator 1, from the upper side as shown in FIG. 1, is defined as the upward direction, and the opposite direction is defined as the downward direction.

[0025] As shown in Figure 1, refrigerator 1 has an insulated box body 11 formed inside with a storage compartment that opens to the front and has a refrigerator compartment 12 located on the upper side and a freezer compartment 13 located on the lower side, an upper left insulated door 16, an upper right insulated door 17, a first middle insulated door 18, a second middle insulated door 19, and a lower insulated door 20.

[0026] The refrigerator 1 is divided into four sections: an upper section that can be opened and closed by an upper left insulated door 16 and an upper right insulated door 17; a first middle section that can be opened and closed by a first middle insulated door 18; a second middle section that can be opened and closed by a second middle insulated door 19; and a lower section that can be opened and closed by a lower insulated door 20.

[0027] The upper left insulated door 16 is a revolving door that can rotate around an axis located at the upper front end of the left side of the insulated box 11 so as to open from the center to the left. The upper right insulated door 17 is a revolving door that can rotate around an axis located at the upper front end of the right side of the insulated box 11 so as to open from the center to the right. The first middle insulated door 18, the second middle insulated door 19, and the lower insulated door 20 are drawer-type doors that can be pulled out and pushed in by moving back and forth to open forward. The upper left insulated door 16, the upper right insulated door 17, the first middle insulated door 18, the second middle insulated door 19, and the lower insulated door 20 can close the front opening of the storage compartment of the insulated box 11.

[0028] The insulated box 11 is configured to have a frame made of, for example, steel plate and a vacuum insulation material housed inside the frame. The vacuum insulation material does not have to be provided. A machine room housing a compressor (not shown) is provided between the frame of the insulated box 11 that forms the lower part of the refrigerator 1 and the vacuum insulation material, and a cooling chamber housing an evaporator (not shown) is formed in the part of the insulated box 11 that forms the back side of the refrigerator 1.

[0029] The evaporator and compressor are connected to an expansion means and a condenser (not shown) via refrigerant piping to form a vapor compression refrigeration cycle. A blower is provided above the cooling compartment, and blows the cool air from inside the cooling compartment cooled by the evaporator to the upper and lower sections of the refrigerator 1. A defrost heater (not shown) is provided below the evaporator to melt frost on the evaporator.

[0030] A pair of upper and lower hinges (lower hinge 31 shown in FIG. 4 and upper hinge not shown) curved leftward are provided on the left side of the insulating box 11. A lower rotation shaft 32 is provided at the tip of the lower hinge 31 as shown in FIG. 4. An upper rotation shaft not shown is provided at the tip of the upper hinge not shown. The top and bottom of the upper left insulating door 16 are rotatably supported relative to the insulating box 11 by the upper rotation shaft and lower rotation shaft 32 not shown, respectively.

[0031] Similarly, a pair of upper and lower hinges (shown) that curve rightward are provided on the right side of the insulated box 11. A rotation shaft (not shown) is provided at the tip of the hinge (not shown). The upper and lower parts of the upper right insulated door 17 are supported by the rotation shaft (not shown) so as to be rotatable relative to the insulated box 11.

[0032] In the following description, the configuration in which the upper right insulated door 17 is rotatably supported by the insulated box body 11 is a configuration that is bilaterally symmetrical in the refrigerator 1 with the configuration in which the upper left insulated door 16 is rotatably supported by the insulated box body 11. For this reason, only the configuration in which the upper left insulated door 16 is rotatably supported by the insulated box body 11 will be described, and the configuration in which the upper right insulated door 17 is rotatably supported by the insulated box body 11 will not be described.

[0033] As shown in FIG. 4 , the lower hinge 31 has a vertical plate-shaped portion 311 fixed to the insulated box 11 and a horizontal portion 312. The horizontal portion 312 is formed of a metal plate that is integrally molded with the vertical plate-shaped portion 311 and bent at a right angle relative to the horizontal portion 312. A lower rotating shaft 32 extending upward is fixed to the extending end of the horizontal portion 312. The base of the lower rotating shaft 32 connected to the horizontal portion 312 passes through an annular hinge spacer 33, which is disposed on the upper surface of the horizontal portion 312. A two-face width cut 321 that forms a pair of parallel flat surfaces is formed on the upper portion of the lower rotating shaft 32. The lower rotating shaft 32 passes through a stopper 35 serving as a support member and a cam 53 of the auto-close device 50.

[0034] The stopper 35 has a metal plate-shaped portion 351, and through holes 352 and 353 are formed in the plate-shaped portion 351. The cam 53 of the auto-closing device 50 and the lower rotation shaft 32 that penetrates the cam 53 pass through the through hole 352, and the stopper 35 supports the lower end of the cam 53. The stopper 35 is rotatable around the axis of the lower rotation shaft 32, and this rotation causes a part of the stopper 35 to abut against a part of the lower hinge 31, thereby preventing the rotation of the upper left insulated door 16 at a predetermined position.

[0035] The auto-closing device 50 is accommodated in the accommodation section 36 and abuts against the stopper 35. The accommodation section 36 is configured as a hollow section that protrudes upward in the vertical direction so that a portion of the door bottom cap attached to the underside of the upper left-side insulated door 16 protrudes into an insulation material accommodation space formed inside the upper left-side insulated door 16 and into which insulation material is injected. The auto-closing device 50 is accommodated in this hollow section. Specifically, as shown in FIG. 5 , the auto-closing device 50 includes a resin base member 51, a resin cam 53, a metal spring holding member 54, and a metal leaf spring 55. The cam 53 is fixed to the insulated box 11, the lower hinge 31, and the lower rotation shaft 32 so as not to rotate. The components that make up the auto-close device 50 other than the cam 53, the stopper 35, and the door lower cap having the storage section 36 are fixed to the upper left insulated door 16, and these rotate around the axis of the lower rotation shaft 32 relative to the insulated box body 11.

[0036] 5, base member 51 is formed in a rectangular parallelepiped shape with a plurality of ribs, and has through holes 512, 513, and 514 formed therein. A recess is formed in the lower surface of base member 51, and stopper 35 is housed in this recess, as shown in FIG. 2. Stopper 35 has through hole 353 formed therein, and stopper 35 is fixed to the lower surface of base member 51 by threading screw 34 through through hole 353 and through hole 513.

[0037] 5, the spring holding member 54 has a bottom plate portion 5411, a back plate portion 542, side plate portions 543, and an upper plate portion 5441, which are formed by bending a metal plate. The bottom plate portion 5411 is formed in a rectangular plate shape. A through hole 5412 is formed in the bottom plate portion 5411. A screw 52 passing through the through hole 514 from the underside of the base member 51 passes through the through hole 5412 and threadedly engages with the through hole 5412, thereby fixing the bottom plate portion 5411 of the spring holding member 54 to the base member 51.

[0038] The back plate portion 542 is formed in a rectangular shape extending upward from one short side of the rectangular bottom plate portion 5411. The side plate portions 543 are formed in a rectangular shape extending upward from the back plate portion 542 on a pair of long sides of the rectangular bottom plate portion 5411. The back plate portion 542 and the pair of side plate portions 543 form a U-shaped wall, as shown in FIG.

[0039] The upper plate portion 5441 (see FIG. 5) is formed in the shape of a rectangular plate extending from the upper end of the back plate portion 542 in parallel to the bottom plate portion 5411. A through-hole 5442 is formed in the extending end of the upper plate portion 5441. The upper end of the cam 53 and the upper end of the lower rotation shaft 32 pass through the through-hole 5442, and the upper end of the cam 53 is supported by the upper plate portion 5441 of the spring holding member 54. As described above, the lower end of the cam 53 is supported by the stopper 35, and therefore the cam 53 is supported by being sandwiched between the upper plate portion 5441 of the metal spring holding member 54 and the stopper 35, which serves as a metal support member.

[0040] Leaf spring 55 has a rear wall portion 5511, a pair of side portions 552, and an engaging protrusion 553, which are formed from a bent metal plate and connected together. Rear wall portion 5511 is formed in a rectangular plate shape. Screws 56 pass through through holes 5512 formed in rear wall portion 5511 and through holes formed in back plate portion 542 and threadably engage with each other, so that rear wall portion 5511 is fixed in a state where its surface abuts against back plate portion 542.

[0041] The pair of side portions 552 extend from a pair of long sides of the rectangular rear wall portion 5511 in a direction perpendicular to the rear wall portion 5511 (toward the lower right in FIG. 5 ), and are each formed as an identical rectangular plate. The pair of side portions 552 abut on the surfaces of the pair of side plates 543 of the spring holding member 54. As a result, the rear wall portion 5511 and the pair of side portions 552 abut on the surfaces of the back plate portion 542 and the pair of side plates 543 of the spring holding member 54, and are surrounded by these. The pair of side plates 543 prevent the pair of side portions 552 and the engagement protrusion 553 from elastically deforming in directions separating them from each other.

[0042] Engagement protrusions 553, which are bent in a V shape and protrude toward each other, are integrally connected to the extending ends of the pair of side portions 552. The protruding portions of the pair of engagement protrusions 553 protrude close to each other and face each other. With this configuration, leaf spring 55 is formed into a C-shape by the rear wall portion 5511, the pair of side portions 552, and the engagement protrusions 553, with the central portion (the portion formed by the rear wall portion 5511 and the pair of side portions 552) being rectangular, and this rectangular central portion is supported by being surrounded by a U-shaped wall formed by the back plate portion 542 and the pair of side plate portions 543 of spring holding member 54, as described above.

[0043] As shown in Fig. 6, the cam 53 includes a cylindrical cam body 531. On the inner peripheral surface of the cam body 531, thick-walled portions 534 having a pair of parallel inner surfaces that increase the thickness of the cam body 531 in the radial direction are formed integrally with the cam body 531. A pair of thick-walled portions 534 are provided at positions in the diameter direction of the cam body 531. The lower rotation shaft 32 is inserted into the internal space formed by the inner peripheral surface of the cam body 531, and the thick-walled portions 534 engage with the two-flat cut 321 formed on the peripheral surface of the lower rotation shaft 32, thereby fixing the cam 53 to the lower hinge 31 and the lower rotation shaft 32 so as not to rotate.

[0044] 6, a plurality of recesses 532 and recesses 533, each having a different depth, are formed on the peripheral surface of cam body 531, specifically two recesses, for a total of four recesses, on less than half the circumference of cam body 531. Recesses 532 and recesses 533 in a cross section perpendicular to the axis of cam body 531 each have an arc shape with a different curvature, and are formed in pairs at symmetrical positions around the axis of cam body 531.

[0045] More specifically, recesses 532 are formed as a pair at positions in the diameter direction of cam body 531, at positions where thick-walled portion 534 is provided. This makes it possible to reinforce the portion of cam body 531 that becomes thin due to the formation of recesses 532, with thick-walled portion 534, which becomes thicker.

[0046] Recess 532 has a radius of curvature r1, and a depth d1 from the circumferential surface of cam body 531. Recess 533 is formed as a pair at a position rotated 90 degrees in the circumferential direction of cam body 531 around the axis of cam body 531 relative to recess 532. Recess 533 has a radius of curvature r2, which is shorter than radius of curvature r1 of recess 532. Recess 533 has a depth d2 from the circumferential surface of cam body 531, which is shallower than d1.

[0047] 7 and 8, a pair of engaging protrusions 553 abuts against and presses against the peripheral surface of cam body 531 so as to sandwich cam body 531 in the diameter direction of cam body 531. As upper left insulated door 16 rotates relative to insulated box body 11, the pair of engaging protrusions 553 move along the peripheral surface of cam body 531 while pressing against the peripheral surface of cam body 531, causing leaf spring 55 to rotate about the axis of lower rotation shaft 32.

[0048] 4, the accommodation portion 36 has a leaf spring accommodation portion 3611 and a base portion accommodation portion 3621. The leaf spring accommodation portion 3611 is formed in a rectangular parallelepiped shape and accommodates a portion of the base member 51 and the auto-closing device 50 by covering them from above. A cylindrical protrusion 3612 is provided on the top surface of the leaf spring accommodation portion 3611 and protrudes upward. The upper end portion of the lower rotation shaft 32 is inserted into the protrusion 3612.

[0049] The base portion accommodating portion 3621 is connected to the leaf spring accommodating portion 3611 and accommodates the remainder of the base member 51 other than the portion accommodated in the leaf spring accommodating portion 3611. A plate-shaped portion 363 protrudes horizontally from the portion of the base portion accommodating portion 3621 opposite to the portion connected to the leaf spring accommodating portion 3611.

[0050] A pair of rectangular plate-like portions 3622 protrude upward from the upper surface of the base portion accommodating portion 3621. A reinforcing plate 37 is provided between the pair of plate-like portions 3622. Each reinforcing plate 37 has a rectangular plate-like bottom portion 371 and a pair of plate-like side portions 372. The pair of plate-like side portions 372 extend upward from a pair of long sides of the rectangular plate-like bottom portion 371, which is a direction perpendicular to the plate-like bottom portion 371, and are integrally molded and connected to the plate-like bottom portion 371.

[0051] A through hole is formed in the plate-shaped bottom portion 371, and a screw 38 passes through the through hole. The screw 38 passes through the through hole of the plate-shaped bottom portion 371 and a through hole 3623 on the upper surface of the base portion accommodating portion 3621 and threads into the through hole, thereby fixing the reinforcing plate 37 to the upper surface of the base portion accommodating portion 3621.

[0052] Next, we will explain the auto-closing and free-stopping functions of the auto-closing device 50. When the upper left-side insulated door 16 is rotated relative to the insulated box 11 to open it from a state in which the upper left-side insulated door 16 closes the front opening of the storage chamber of the insulated box 11, the pair of engaging protrusions 553 of the leaf spring 55 move circumferentially on the peripheral surface along the portion of the peripheral surface of the cam body 531 where the recesses 532 and 533 are not formed while pressing against that portion.

[0053] Then, when the pair of engaging protrusions 553 each begin to enter the recess 533, they are guided to the deepest part of the recess 533 so as to fall into the recess 533, resulting in a so-called free stop state as shown in Figure 7, in which the front opening of the storage compartment of the insulated box body 11 can be temporarily maintained open at a predetermined angle of about 90 degrees relative to the state in which the upper left insulated door 16 is closed.

[0054] Next, when the upper left insulated door 16, which is in the free stop state shown in Fig. 7, is rotated relative to the insulated box body 11 in the direction in which the front opening of the storage compartment of the insulated box body 11 closes, the pair of engaging protrusions 553 of the leaf spring 55 moves from the recessed portion 533 onto the portion of the circumferential surface of the cam body 531 where the recessed portion 533 is not formed. Then, the pair of engaging protrusions 553 move circumferentially on the circumferential surface along the portion of the circumferential surface of the cam body 531 where the recessed portion 532 and the recessed portion 533 are not formed, while pressing against this portion.

[0055] When the pair of engaging protrusions 553 begin to enter the recess 532, they are guided toward the deepest part of the recess 532 so as to fall into the recess 532, thereby achieving an auto-close function in which the upper left-hand insulated door 16 is rotated to a state in which it closes the front opening of the storage compartment of the insulated box 11, as shown in Fig. 8. The deepest part of the recess 532 is located at a position where it is assumed that the engaging protrusions 553 will be located when the upper left-hand insulated door 16 is virtually rotated by a further predetermined angle from the state in which the upper left-hand insulated door 16 closes the front opening of the storage compartment of the insulated box 11, as shown in Fig. 8. This prevents the upper left-hand insulated door 16 from being slightly open at the front opening of the storage compartment of the insulated box 11 and not being closed.

[0056] The refrigerator 1 according to the present embodiment having the above-described configuration can achieve the following effects. In this embodiment, multiple recesses 532 and 533 are formed on less than half of the circumferential surface of cam 53. A leaf spring engages with recess 533, which serves as one of the recesses, to maintain upper-left insulated door 16 open at a predetermined angle. Leaf spring 55 rotates along the circumferential surface of cam 53, and engages with recess 532, which serves as the other recess, to rotate upper-left insulated door 16 to a position that closes the front opening of the storage compartment. This simple configuration, consisting of one cam 53 and leaf spring 55 moving along the circumferential surface of cam 53, can achieve not only the auto-close function of upper-left insulated door 16 but also the free-stop function. This reduces the number of parts and manufacturing costs, enabling a compact refrigerator configuration.

[0057] Furthermore, in this embodiment, leaf spring 55 is made of a single C-shaped metal plate with a rectangular central portion, and recesses 532 and 533 are formed in pairs at diametrically symmetrical positions about the axis of cam 53. This allows leaf spring 55 to sandwich cam 53 in the diametrical direction of cam 53, and leaf spring 55 can be engaged with recesses 532 and 533. This ensures that the auto-close and free-stop functions can be performed reliably.

[0058] Furthermore, because the central portion of leaf spring 55 is rectangular, leaf spring 55 can be manufactured with high precision, thereby reducing manufacturing costs. Furthermore, leaf spring 55 can be made elongated in the direction in which pair of side portions 552 extend from rear wall portion 5511, and the distance between pair of side portions 552 can be shortened to make the shape compact. This allows a larger insulation material storage space to be formed inside upper left-side insulated door 16 and into which insulation material is injected, and a larger amount of insulation material can be secured in the thickness direction of upper left-side insulated door 16, making it possible to suppress increased power consumption and the effects of condensation due to deterioration of insulation.

[0059] Furthermore, in this embodiment, a metal leaf spring holding member 54 is provided that abuts against and surrounds a pair of side portions 552 in the center of leaf spring 55 and a rear wall portion 5511 that connects the pair of side portions 552. This makes it possible to reinforce the force that clamps cam 53 by C-shaped leaf spring 55, and to reliably engage leaf spring 55 with recesses 532 and 533. Furthermore, since there is no need to increase the thickness of leaf spring 55, processing related to the manufacture of leaf spring 55 can be facilitated.

[0060] In this embodiment, cam 53 is supported by being sandwiched between leaf spring holding member 54 and stopper 35, which serves as a metal support member. As a result, cam 53 is supported by being sandwiched between metal members, which makes it possible to prevent the structure supporting cam 53 from becoming easily damaged, thereby improving reliability.

[0061] In this embodiment, the support member is configured by a stopper 35 that stops the rotation of the upper left insulating door 16 at a predetermined position. As a result, the cam 53 can be supported by being sandwiched between the strong stopper 35 and the leaf spring holding member 54, which reliably prevents the structure supporting the cam 53 from becoming easily damaged, thereby enabling further improvement in reliability.

[0062] In this embodiment, the depths of recess 532 and recess 533 of cam 53 are different. As shown in Fig. 8, recess 532, which is deeper than recess 533, is positioned so that engaging protrusion 553 of leaf spring 55 engages with recess 532 when upper left insulating door 16 closes the front opening of the storage chamber of insulating box 11. As shown in Fig. 7, recess 533, which is shallower than recess 532, is positioned so that engaging protrusion 553 of leaf spring 55 engages with recess 532 when upper left insulating door 16 is in a free stop state in which the front opening of the storage chamber of insulating box 11 can temporarily be maintained open at a predetermined angle of about 90 degrees from the closed state.

[0063] As a result, when the engaging protrusion 553 of the leaf spring 55 engages with the recess 532 having a deep depth, the engaging protrusion 553 of the leaf spring 55 is less likely to come off the recess 532 than when the engaging protrusion 553 of the leaf spring 55 engages with the recess 533 having a shallow depth. This reliably encourages the engaging protrusion 553 of the leaf spring 55 to engage with the recess 532, preventing the upper left insulated door 16 from being ajar. On the other hand, because the recess 533 is shallow, the user of the refrigerator 1 can easily transition to the free stop state, and does not place a large load on the user when releasing the free stop state. Furthermore, when the user wants to open or close the upper left insulated door 16 to an angle (e.g., fully open) of the upper left insulated door 16 that exceeds the free stop position, the user is not placed under a large load when the engaging protrusion 553 of the leaf spring 55 passes through the recess 533.

[0064] In this embodiment, recesses 532 and 533 of cam 53 in a cross section perpendicular to the axis of cam 53 have arc shapes with different curvatures. As shown in Fig. 8, recess 532, which has a larger radius of curvature than recess 533, is positioned at a position where engaging protrusion 553 of leaf spring 55 engages with recess 532 when upper left-hand insulating door 16 closes the front opening of the storage compartment of thermally insulated box 11. As shown in Fig. 7, recess 533, which has a smaller radius of curvature than recess 532, is positioned at a position where engaging protrusion 553 of leaf spring 55 engages with recess 532 when upper left-hand insulating door 16 is in a free-stop state where the front opening of the storage compartment of thermally insulated box 11 can temporarily be kept open at a predetermined angle of about 90 degrees from the closed state.

[0065] This allows the engaging protrusion 553 of the leaf spring 55 to fit more easily into the recess 532 having an arc shape with a large radius of curvature than into the recess 533 having an arc shape with a small radius of curvature. This allows the upper left insulating door 16 to be reliably brought into auto-close mode even if the user does not close the door with enough force.

[0066] The present invention is not limited to the above-described embodiment and can be modified within the technical scope described in the claims. For example, the shape and configuration of the auto-close device and the members supporting the auto-close device are not limited to the shape and configuration of the auto-close device 50 and the members supporting the auto-close device 50 in this embodiment. For example, while the stopper 35 is used as a metal support member, this is not limiting and other metal members can be used. Furthermore, while a total of four recesses 532, 533 are formed, this number is not limited and more than one may be formed, as long as multiple recesses are formed on less than half of the circumferential surface of the cam.

[0067] In addition, in this embodiment, the auto-close device 50 is provided at the bottom of the upper left insulated door 16, but this is not limiting. The auto-close device may also be provided at the top of the upper left insulated door or the top of the upper right insulated door.

[0068] In addition, in this embodiment, the two-face width cut 321 is formed on the lower rotating shaft 32, and the pair of thick portions 534 having a pair of parallel inner surfaces is provided on the cam 53, but this is not limiting. For example, the cam may be provided with only one of the pair of thick portions 534, and the lower rotating shaft may be formed with a D-cut shape that is cut on one face instead of two faces so as to be engageable with this. [Explanation of symbols]

[0069] 1...refrigerator 11...insulating box body 16...upper left insulated door 31...lower hinge 32...lower rotating shaft 35...stopper (supporting member) 53...cam 54...leaf spring holding member 55...leaf spring 532, 533...recess 552...side portion 5511...rear wall portion d1, d2...depth r1, r2...radius of curvature

Claims

1. a heat-insulating box having a storage chamber formed therein; an insulating door that is rotatably supported around a rotation axis supported on the insulating box body and that can open and close a front opening of the storage chamber by rotating around the rotation axis; a hinge attached to the insulating box body to support the insulating door; a cam fixed to the hinge so as not to rotate and having a recess formed on its circumferential surface; a leaf spring that rotates along the peripheral surface of the cam while pressing the peripheral surface of the cam so as to be engageable with the recessed portion of the cam, a plurality of recesses are formed on a peripheral surface of the cam that is less than halfway around the cam, The refrigerator has a structure in which the leaf spring is engaged with one of the recesses, thereby maintaining the insulated door open at a predetermined angle, and the leaf spring rotates along the circumferential surface of the cam and engages with the other recess, thereby rotating the insulated door to a position that closes the front opening of the storage compartment.

2. The leaf spring is made of a single C-shaped metal plate with a rectangular central portion, The refrigerator according to claim 1, wherein the one recess and the other recess are formed in pairs at symmetrical positions with respect to the axis of the cam.

3. The refrigerator according to claim 2, further comprising a metal leaf spring holding member that abuts against and surrounds a pair of side portions of the center of the leaf spring and a rear wall portion connecting the pair of side portions.

4. The refrigerator according to claim 3, wherein the cam is supported by being sandwiched between the leaf spring holding member and a metal support member.

5. 5. The refrigerator according to claim 4, wherein the cam engages with a base member disposed above the support member by passing through a through hole formed in the base member.

6. 5. The refrigerator according to claim 4, wherein the support member is a stopper that stops the rotation of the heat-insulating door at a predetermined position.

7. The refrigerator according to claim 1 , wherein the depths of the recesses of the cam are different.

8. The refrigerator according to claim 1, wherein the plurality of recesses of the cam in a cross section perpendicular to the axis of the cam have arc shapes with different curvatures.

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