Refrigerator having a cool air distributing device

Abstract: A refrigerator has cool air distributing blades (33, 57). The blades (33, 57) are rotatably disposed near cool air discharge ports (16) opening into a cooling compartment (3). The discharge direction of the cool air is determined by angular positions of the blades (33, 57). The blades (33, 57) are driven intermittantly so that air is supplied in a first direction for a period and then supplied in a different direction.

Description: The present invention relates to a refrigerator comprising a cooling compartment, an aperture opening into the compartment, a heat pump and cool air distributing means for supplying cool air generated by the heat pump to the compartment through the aperture, the cool air distributing means including a vertical blade, pivotable about a vertical axis when the refrigerator is in its operational orientation, for directing cool air being supplied to the compartment through the aperture and drive means for pivoting the blade. Generally, a refrigerator has a cabinet in which there are a freezing compartment and a fresh food compartment. These compartments are separated by a partition wall. Doors are provided at the front of the freezing and cooling compartments. A cooling system supplies the freezing compartment and the fresh food compartment with cool air and comprises a compressor, a condenser and an evaporator. The cool air generated by the evaporator flows along a supply duct formed at the back of each compartment, and is then supplied into each cooling compartment through cool air discharge ports opening thereinto by a fan. In such a conventional refrigerator, however, cool air tends to be supplied into a particular area of the cooling compartment and other areas tend to be less well served. Consequently, a uniform temperature is not maintained throughout the cooling compartment. This problem has been addressed by providing cool air discharge ports in the side walls of the cooling compartment as well as in its rear wall. However, there may be still a dead-zone at an edge area which is not supplied with the cool air sufficiently. Furthermore, the ducting required to supply cool air from the sides of the cooling compartment reduces the space available for food and increases the cost of manufacture. The problem of adequately distributing cool air in a refrigerator is worse for larger refrigerators. Figures 1 through 3 are a side view, a partial enlarged sectional view, and an exploded perspective view of the main elements of a refrigerator having a device for dispersing cool air as disclosed in WO-A-95/27178. Referring to Figures 1 to 3, a refrigerator comprises freezing and fresh food compartments 2, 3 in a cabinet 1, which are separated from each other by a partition 5. Respective doors 6, 7 are provided for closing the compartments 2, 3. A cooling system, comprising a compressor 11, a condenser (not shown), a freezing compartment evaporator 12a, and a fresh food compartment evaporator 12b, is installed in the cabinet 1. Cool air generated by the evaporators 12a, 12b is supplied to the corresponding compartments 2, 3 by a freezing compartment fan 13a and a fresh food compartment fan 13b respectively. A partially cylindrical duct plate 9 is attached to an inner wall plate 23 forming the rear inner wall surface of the fresh food compartment 3. The duct plate 9 has cool air discharge ports 16, opening into the fresh food compartment 3, formed in it. A supply duct 15 and a return duct 17, separated from each other by a seal plate 25, are provided between the duct plate 9 and the rear wall 4 of the cabinet 1. A duct member 21, for guiding downwards cool air blown by the fresh food compartment fan 13b, is installed in the supply duct 15. Cool air generated by the fresh food compartment evaporator 12b is blown by the fresh food compartment fan 13b and then supplied to the fresh food compartment 3 via the supply duct 15 and the cool air discharge ports 16. A cool air dispersing device 130 is installed in the supply duct 15. The cool air dispersing device 130 comprises a rotational shaft 131 having a vertical axis, cool air dispersing blades 132 assembled with the rotational shaft 131 in correspondence with respective cool air discharge ports 16, and a driving motor 135 for rotating the rotational shaft 131. Each of the cool air dispersing blades 132 comprises three discs 136, 137, 138 disposed in parallel with each other along the shaft 131, and first and second blade parts 133, 134 disposed between pairs of the discs 136, 137, 138. Each of the blade parts 133, 134 is curved so that its cross-section is loosely S-shaped. The blade parts 133, 134 are bent in opposite directions to each other. In a refrigerator having the above-described constitution, when the driving motor 131 rotates the rotational shaft 131 at a low speed, cool air flowing along the supply duct 15 changes its direction along the curved surfaces of the cool air dispersing blades 132, and is directed into the fresh food compartment 3 so as to disperse horizontally. When concentrated cooling in a specific area is needed, the driving motor 135 stops the rotational shaft 131 so that the cool air dispersing blades 132 direct cool air to the specific area. However, since the blade parts 133, 134 of the cool air dispersing device 130 are S-shaped, the left or right sides of the fresh food compartment 3 may not be supplied with the cool air sufficiently and the smooth flow of cool air may be impeded by a vortices in the cool air formed about the cool air discharge ports 16. The present invention has been proposed to overcome the above- described problems in the prior art, and accordingly it is the object of the present invention to provide a refrigerator having a cool air dispersing device capable of preventing vortex of cool air and distributing the cool air effectively. A refrigerator according to the present invention is characterised by control means for controlling the drive means such that the blade moves intermittently between a plurality of angular positions, the control means being responsive to the output of the temperature sensor to control the time during which the blade stops at a particular angular position. Preferably, the cool air distributing means includes a further blade which is pivotable about a horizontal axis when the refrigerator is in its operational orientation. More preferably, the further blade is driven intermittently by said drive means. Still more preferably, , pivoting means is included for pivoting said further blade and said pivoting means comprises a link member having a hinge assembly part assembled with said further blade at a position distanced from said horizontal axis, said link member being capable of moving up and down, and a means for raising and lowering said link member. Yet more preferably, said raising and lowering means comprises a cam installed on and rotating with a rotational shaft, on which the vertical blade is mounted, and an operation part formed in a body with said link member, said operation part interacting with said cam so that rotational movement of said cam is transmitted to said link member as a vertical reciprocal motion thereof. Optionally, a means is provided for guiding said link member so as to be capable of moving up and down vertically while preventing rotation of said link member. Preferably, a temperature sensor is included and the control means is responsive to the output of the temperature sensor to control the time during which the further blade stops at a particular angular position. Preferably, a duct is provided in a side wall of said cooling compartment to form a cool air passage and said aperture connects said duct to said cooling compartment. A refrigerator according to any preceding claim, wherein said driving motor is a stepping motor. An embodiment of the present invention will now be described, by way of example, with reference to Figures 4 to 14 of the accompanying drawings, in which:- Figure 1 is a side sectional view of a conventional refrigerator having cool air dispersing blades; Figure 2 is a partial enlarged sectional view of Figure 1; Figure 3 is an enlarged exploded perspective view of the main elements of Figure 2; Figure 4 is a front view of a first refrigerator according to the present invention; Figure 5 is a side sectional view of Figure 4; Figure 6 is an enlarged exploded perspective view of the cool air dispersing device shown in Figure 5; Figure 7 is a block diagram illustrating the control of the cool air dispersing device; Figures 8 through 10 are enlarged transverse sectional views showing the cool air dispersing process performed by the horizontally dispersing blades; Figures 11 through 13 are enlarged side sectional views showing the cool air dispersing process performed by the vertically dispersing blades; and Figure 14 is a flow chart illustrating the control process of the refrigerator not according to the invention. Hereinafter, an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings. Parts that are the same as or similar to parts shown in Figures 1 through 3 will be identified with the same reference numerals. The description of the parts which are substantially the same as those of the prior art will be omitted. Referring to Figures 4 and 5, a refrigerator according to the present invention comprises a freezing compartment 2 and a cooling compartment 3 in a cabinet 1. The compartments 2, 3 are separated by a horizontal partition. Doors 6, 7 are provided respectively for the compartments 2, 3. Shelves 8 for supporting food are provided in the fresh food compartment 3 and divide it into three areas one above another. A special fresh chamber 18 for storing food that requires a specific temperature range is formed at the top of the fresh food compartment 3 and a vegetable chamber 19 for storing vegetables is formed at the bottom of the fresh food compartment 3. A heat pump, comprising a compressor 11, a condenser (not shown), a freezing compartment evaporator 12a, and a fresh food compartment evaporator 12b, is installed in the cabinet 1. Cool air generated by the evaporators 12a, 12b is supplied into the corresponding cooling compartments 2, 3 by the freezing compartment fan 13a and the fresh food compartment fan 13b. A supply duct 15 and a return duct 17 are provided at the back of the fresh food compartment 3. The cool air generated by the fresh food compartment evaporator 12b is driven by the fresh food compartment fan 13b into the fresh food compartment 3 via the supply duct 15 and the cool air discharge ports 16. A device for dispersing the cool air horizontally is installed in the supply duct 15. A pair of temperature sensors 9a, 9b are installed in the fresh food compartment 3. The first temperature sensor 9a is installed in the upper left portion of the fresh food compartment 3 and the second temperature sensor 9b is installed in the lower right portion of the fresh food compartment 3. The refrigerator has a device 30 for dispersing cool air horizontally and a device 40 for dispersing the cool air vertically. The horizontally-dispersing device 30 has a verical shaft 31, three horizontal-dispersing blades 33 having the shape of a planar plate, and a driving motor 35 for rotating the rotational shaft 31. Three horizontally-dispersing blades 33 are spaced along the shaft 31 near respective cool air discharge ports 16. A coupling part 39 at the upper end of the rotational shaft 31 is coupled to a drive shaft 36 of the driving motor 35 and a journal part 32 at the bottom of the rotational shaft 31 is rotatably received in a bearing hole 9g at the bottom of the duct plate 9. It is preferable that the driving motor 35 be a stepping motor whose angular stop position can be controlled. Thus, when the driving motor 35 operates, the horizontally-dispersing blades 33 are rotated by the rotational shaft 31, and cool air is discharged through the cool air discharge ports 16 and dispersed horizontally. The vertically-dispersing device 40 comprises a plurality of vertically-dispersing blades 57 which are disposed near the cool air discharge ports 16 and which are capable of pivoting about respective horizontal axes, a vertically reciprocable link member 61 in the supply duct 15, and a raising and lowering cam 63 for raising and lowering the link member 61. The vertically-dispersing blades 57 are arcute so as to accommodate the horizontally-dispersing blades 33, and a horizontal stub shaft 53 extend horizontally from the left and right ends thereof. The duct plate 9 has two opposed flange parts 9e which extend backward from its side margins. The flange parts 9e have a plurality of shaft holes 9f for receiving and rotatably supporting the stub shafts 53. The link member 61 is disposed parallel to the rotational shaft 31. The link member 61 is rod-shaped and has a plurality of partially ring-shaped hinge assembly parts 62 which protrude towards respective vertical- dispersing blades 57. Each of the vertically-dispersing blades 57 has a horizontal, cylindrical hinge part 55 at the middle of its front edge. The hinge assembly parts 62 are engaged by the hinge parts 73 so as to be capable of rotating relatively thereto. The raising and lowering cam 63 is installed on the rotational shaft 31. The raising and lowering cam 63 comprises a cylindrical cam body 66 and a cam groove 65 formed on the outer surface of the cam body 66. The cam groove 65 is a closed loop having a raising and lowering profile. On the link member 61 is provided an operation part 67 protruding transversely to the longitudinal direction of the link member and the free end of the operation part 67 is received in the cam groove 65. Furthermore, the link member 61 has a guiding piece 69 protruding toward the duct plate 9. The guiding piece 69 is accommodated in the raising and lowering guiding part 49 formed on the inner wall of the duct plate 9. The raising and lowering guiding part 49 accommodates the guiding piece 69 so as to guide it up and down and prevent the link member 61 from rotating. Referring to Figure 7, a microprocessor 90 receives signals from the first and second temperature sensors 9a, 9b. If the sensed temperatures are higher than a temperature that a user has set using a control unit 92, the microprocessor 90 operates the compressor 11 and the fans 13a, 13b to generate the cool air and drives the driving motor 35 to control the cool air dispersing device. A power supply 91 is provided for supplying electrical power to the microprocessor 90, and a timer 95 is provided for providing the microprocessor 90 with time information. Referring to Figure 8, when the horizontally-dispersing blades 33 are directed to the front, cool air in the supply duct 15 is discharged directly to the front along both sides of the horizontally-dispersing blades 33. When the horizontally-dispersing blades 33 are rotated to the left or the right, as shown in Figures 9 and 10, cool air is discharged toward the left or the right. While the horizontally-dispersing device 30 is operating, the rotation of the rotational shaft 31 causes the raising and lowering cam 63 to rotate and the link member 61 is raised andlowered by the operation part 67 by the raising and lowering cam 63. The rising and falling movement of the link member 61 causes pivoting of the vertically-dispersing blades 57 by means the hinge assembly part 62 and the hinge part 55 of the vertically-dispersing blades 57. The up and down motion of the link member 61 is guided by the guiding piece 69 and the raising and lowering guiding part 49. Therefore, the link member 61 does not rotate but reciprocates in the vertical direction while the raising and lowering cam 63 rotates. Referring to Figure 11, while the vertically-dispersing blades 71 are kept horizontal, the cool air is discharged horizontally. When the rotational shaft 31 rotates right, the vertically-dispersing blades 57 are tilted upward as shown in Figure 12, and in this situation, the cool air is discharged upward into the upper area of the fresh food compartment 3. Also, as the rotational shaft 31 rotates left, the vertically-dispersing blades 57 are tilted downward as shown in Figure 13. In this situation, the cool air is discharged downward. The operation of a refrigerator which is not part of the invention will now be described with reference to Figure 14. The microprocessor 90 checks (step S1) whether the fans 13a, 13b are running or not. If the fans 13a, 13b are running, the microprocessor 90 sets (step S2) the timer 95 to zero, and then stops (step S3) the horizontally-dispersing blades 33 as shown in Figure 8 so that cool air is discharged directly forward. In this situation, the vertically-dispersing blades 57 are in the horizontal state as shown in Figure 11. Therefore, cool air is discharged horizontally. The microprocessor 90 monitors the passage of time by means of the timer 95 and, when the elapsed time reaches sixty seconds (step S4), drives the driving motor 35 to rotate (step S5) the horizontally-dispersing blades 33 left as shown in Figure 9. In this situation, the vertically-dispersing blades 57 are rotated downward as shown in Figure 13. Therefore, cool air is discharged downwards to the left. The microprocessor 90 monitors the passage of time by means of the timer 95 again, and when the elapsed time reaches one hundred and twenty seconds (steps S6), drives the driving motor 35 to rotate (step S7) the horizontally-dispersing blades 33 to their original position. Accordingly, the horizontally-dispersing blades 33 and the vertically-dispersing blades 57 are positioned as shown in Figure 8 and 11 respectively and cool air is discharged directly forward and horizontally again. When the elapsed time reaches one hundred and eighty seconds (step S8), the microprocessor 90 drives the driving motor 35 again to rotate (step S9) the horizontally-dispersing blades 33 to the right as shown in Figure 10. In this situation, the vertical-dispersing blades 57 are rotated upward as shown in Figure 12. Therefore, cool air is discharged upwardly to the right. As the elapsed time monitored by the timer 95 reaches two hundred forty seconds (step S10), the microprocessor 90 returns to its initial state to check whether the fans 13a, 13b running or not and to reset the timer 95. According to such a process, cool air is supplied to the left lower part, the central part, and the right upper part for sixty seconds each. Therefore, cool air is supplied more effectively distributed in the fresh food compartment 3 when comparison with a conventional refrigerator which supplies cool air by means of continuously rotating cool air dispersing blades. Furthermore, since the horizontally-dispersing blades 33 and the vertically-dispersing blades 57 are planar, vortices are not formed in the cool air flow during the cool air dispersing operation. In the example of figure 11, horizontally-dispersing blades 33 are disposed in correspondence to the cool air discharge ports 16. However, one could use one horizontally-dispersing blade extending passed all of the cool air discharge ports 16. Furthermore, in the present embodiment, the vertically-dispersing blades 57 operate together with the horizontally-dispersing blades 33. However, these could be driven independently by a separate driving means. That is, if an additional driving motor controlled by the microprocessor 90 is provided and the link member 61 is operated not by the raising and lowering cam 63 but by the additional driving motor, it is possible to control the stop positions of the vertically-dispersing blades 57. Then, the vertically-dispersing blades 57 are controlled so that they are stopped at upper, central, and lower angular positions successively during predetermined times respectively, whereby the vertically-dispersing blades 57 can independently supply the cool air at vertical positions in the fresh food compartment 3. In this situation, it is preferable that the time interval for changing the angular position of the vertically-dispersing blades 57 is different from that of the horizontal-dispersing blades 33. For example, if the horizontally-dispersing blades 33 are driven with the time interval of sixty seconds as described above, the vertically-dispersing blades 57 are preferably driven with the time interval of forty seconds. Then, the cool air is supplied to more areas of the fresh food compartment 3. Furthermore, in the example of figure 11, the time durations that the blades 33 and 57 are stopped at respective angular positions are the same with each other, however, in the present invention they are controlled on the basis of the outputs of the temperature sensors 9a, 9b so that a greater amount of cool air is discharged to less cool areas. In other words, if the temperature of the area, in which the first temperature sensor 9a is installed, is higher than that of the other areas, the driving motor 35 is controlled so that the time that the blades 33, 57 are stopped so as to direct cool air toward the first area is longer than the time during which cooling air is directed toward the other areas. Consequently, the uniform distribution of the temperature in the fresh food compartment 3 can be achieved more effectively. In this case, it is possible that the temperatures at a plurality of positions are sensed by a plurality of temperature sensors. If the horizontally-dispersing blades 33 and the vertically-dispersing blades 57 are driven independently of each other as illustrated above-described modified embodiment, it is easy to supply a greater amount of cool air to the least cool area.

Claims: A refrigerator comprising a cooling compartment (3), an aperture (16) opening into the compartment (3), a heat pump (11,12b), a temperature sensor (9a, 9b) and cool air distributing means (13b, 30) for supplying cool air generated by the heat pump (11, 12b) to the compartment (3) through the aperture (16), the cool air distributing means including a vertical blade (33), pivotable about a vertical axis when the refrigerator is in its operational orientation, for directing cool air being supplied to the compartment (3) through the aperture (16) and drive means (31, 35, 63, 61) for pivoting the blade (33, 57), characterised by control means (90) for controlling the drive means (31, 35, 63, 61) such that the blade (33) moves intermittently between a plurality of angular positions, the control means (90) being responsive to the output of the temperature sensor (9a, 9b) to control the time during which the blade (33) stops at a particular angular position. A refrigerator according to claim 1, wherein the cool air distributing means includes a further blade (57) which is pivotable about a horizontal axis when the refrigerator is in its operational orientation. A refrigerator according to claim 2, wherein the further blade (57) is driven intermittently by said drive means (31, 35, 63, 61). A refrigerator according to claim 3, wherein the control means (90) is responsive to the output of the temperature sensor (9a, 9b) to control the time during which the further blade (57) stops at a particular angular position.. A refrigerator according to any preceding claim, including a duct (15) provided in a side wall of said cooling compartment (3) to form a cool air passage, wherein said aperture (16) connects said duct (15) to said cooling compartment (3). A refrigerator according to claim 2 or 3, including pivoting means for pivoting said further blade (57), wherein said pivoting means comprises a link member (62) having a hinge assembly part assembled with said further blade at a position distanced from said horizontal axis, said link member being capable of moving up and down, and a means (65, 67) for raising and lowering said link member (62). A refrigerator according to claim 6, wherein said raising and lowering means (65, 67) comprises a cam (65) installed on and rotating with a rotational shaft (31), on which the vertical blade (33) is mounted, and an operation part (67) formed in a body with said link member (62), said operation part interacting with said cam (65) so that rotational movement of said cam (65) is transmitted to said link member (62) as a vertical reciprocal motion thereof. A refrigerator according to claim 7, further comprising a means (49, 69) for guiding said link member (62) so as to be capable of moving up and down vertically while preventing rotation of said link member (62). A refrigerator according to any preceding claim, wherein said driving motor is a stepping motor. A refrigerator according to any preceding claim, wherein the or each blade is planar.

Inventors: KIM JAE IN, PARK HAE JIN, KIM, JAE IN, PARK, HAE JIN
Applicants: SAMSUNG ELECTRONICS CO LTD, SAMSUNG ELECTRONICS CO., LTD.
Application year: 1998
Main classification: F25D11
IPC codes: F24F13, F25D17, F25D23