Patent Application
20050138950
This invention relates to a drive device of an automatic ice machine mounted in a domestic electric refrigerator, and automatically making ice and storing the same.
A drive device of an automatic ice machine mounted in a domestic electric refrigerator disclosed in Patent Laid Open 2001-272146 automatically supplies water on an ice tray disposed in a refrigeration room, and after frozen, discharges ice from the ice tray by the drive device.
Ice tray 1 includes a thermister and a heater. When water in ice tray 1 is frozen, and the thermister detects completion of making ice, the heater is electrically conducted. When ice begins melting at an ice surface contacting ice tray 1, the electric conduction to heater 1 is finished, and subsequently the conduction to the motor begins. When moving paw 13 is rotated 360° by rotation of the motor, ice in ice tray 1 is discharged. The discharged ice is sent to the ice box. After moving pawls 3 are rotated 360°, ice tray 1 is supplied with water, and again the ice making work is started. The above work is repeated until stop arm 4 detects predetermined amount of ice.
However, in the drive device of the existing automatic ice machine, since ice is easily removed from the ice tray, ice shapes are uniformly rounded. Less round and rock like ice cannot be made, which is demanded by consumers.
In view of the above problem, the invention is to provide the drive device of the automatic ice machine which makes rocky ice.
For solving the existing problem, the drive device of the automatic ice machine of the invention is composed of a motor, a first output shaft and a second output shaft having a positional relation of mutually crossing, and a reduction gear which reduces rotation of the motor and transmits respectively different driving forces to the first output shaft and the second output shaft, and crushes ice with the second output shaft, rotates the ice tray by the first output shaft, and separates crushed ice from the ice tray. Since ice is crushed by the second output shaft, ice will be less round and rocky.
In the following description, explanation will be made to the embodiment of the drive device of the automatic ice machine according to the invention in reference to the drawings. The invention is not limited to this embodiment.
In
First output shaft 14 projects horizontally from vertical wall 11a of case 11. Second output shaft 15 projects vertically from horizontal wall 11b of case 1. Both of first output shaft 14 and second output shaft 15 are driven by gear train 13. Second output shaft 15 is formed at a front end in cross (+) shape. Gear train 13 includes pinion gear 131, first output gear 132, gear 133, worm gear 134, worm wheel gear 135, gear 136, and second output gear 137. Motor 12 drives pinion gear 131. First output gear 132 is provided as one body with first output shaft 14, while second output gear 137 is provided as one body with second output shaft 15.
Since first output shaft 14 and second output shaft 15 have a positional relation of mutually crossing, reduction gear 13 transmits rotation running around an axis of a horizontal direction to first output shaft 14, and transmits rotation around the axis of a vertical direction to second output shaft 15. The gear train is so composed as to change the rotating direction by 90°. In the embodiment, gear 133 and worm gear 134 are coaxially formed as one body, and compose double reduction gear 13a. Since gear 133 is disposed inside of vertical wall 11a of case 11, and worm gear 134 is disposed inside of horizontal wall 11b of case 11, the rotating directions of gear train 13 are different by 90° with respect to the side of vertical wall 11a and the side of horizontal wall 11b of case 11.
In gear train 13, reduction gear ratio until a first output gear and reduction gear ratio until a second output gear are different. Specifically, the second output gear is set to be sufficiently slow in rotating in comparison with the first output gear. In the embodiment, while the first output gear rotates 180°, the second output gear rotates about 5°.
Ice tray 16 is disposed on the horizontal surface of case 11 to encircle second output shaft 15. When supplying water into ice tray 16, second output shaft 15 is buried in water, leaving a little part of a front end thereof.
As shown in
In regard to the drive device of the automatic ice machine structured as above, the actuation thereof will be explained.
When ice tray 16 is supplied with a proper quantity of water and the ice-making is completed, a controller (not shown) rotates motor 12. The rotation of motor 12 is transmitted to first output shaft 14 and second output shaft 15 through gear train 13. Since first output shaft 14 is secured to the wall within the refrigerator, by driving first output shaft 14, drive device 10 and ice tray 16 start rotation. Reduction gear ratio from the motor 12 until the second output gear 137 is larger than reduction gear ratio from the motor 12 until the first output gear 132. Specifically, when first output gear 132 rotates 180°, that is, when drive device 10 and ice tray 16 turn over 180°, second output gear 137 rotates about 50.
Second output shaft 15 is blocked from rotation by ice, but the second output gear rotates at torque exceeding this blocking, so that ice is crushed by second output gear 137. Ice is then broken into irregularly polygons, becomes so-called rocky, and is stored in the ice box under ice tray 16.
It has been confirmed by applicant's experiments that by making a shape of second output shaft 15 cross (+), ice is broken into four pieces.
The cross sectional shape of second output shaft 15 is not limited to the cross (+), but shapes sufficient to break ice by rotation, for example, a Y shape will do.
In
First output shaft 14 projects horizontally from vertical wall 21a of case 21. Second output shaft 15 and third output shaft 24 project vertically upward from horizontal wall 21b of case 21. First output shaft 14, second output shaft 15 and third output shaft 24 are all driven by reduction gear train 23. Second output shaft 15 and third output shaft 24 are formed at front ends in cross (+) shape. Reduction gear train 23 includes pinion gear 131, first output gear 132, gear 133, worm gear 134, worm wheel gear 135, gear 136, second output gear 137, gear 138, transmission gear 139, and third output gear 140. Motor 12 drives pinion gear 131.
First output gear 132 is provided as one body with first output shaft 14, second output gear 137 is provided as one body with second output shaft 15, and third output gear 140 is provided as one body with third output shaft 24.
Ice tray 16 is disposed on the horizontal surface of case 21 to encircle second output shaft 15 and third output shaft 24. When supplying water into ice tray 16, second output shaft 15 and third output shaft 24 are buried in water leaving a little part of each of their front ends.
In regard to the drive device of the automatic ice machine structured as above, the actuation thereof will be explained.
When water supplied in ice tray 16 is frozen and the ice-making is completed, the controller (not shown) rotates motor 12. Rotation of motor 12 is transmitted to first output shaft 14, second output shaft 15 and third output shaft 24 through reduction gear train 23. Since first output shaft 14 is secured to the wall within the refrigerator, by driving first output shaft 14, drive device 20 and ice tray 16 rotate.
Reduction gear ratios from motor 12 until second output gear 137 and third output gear 138 are larger than reduction gear ratio from motor 12 until first output gear 132. When first output gear 132 rotates 1800, that is, when drive device 20 and ice tray 16 rotate 1800, second output gear 137 and third output gear 138 rotate about 50.
Second output shaft 15 and third output shaft 24 are blocked from rotation by ice, but second output shaft 15 and third output shaft 24 rotate at torque exceeding this blocking, so that ice is crushed. Ice is then broken into irregular polygons, becomes so-called rocky, and is stored in the ice box under ice tray 16.
In this embodiment, two output shafts for breaking ice are provided, so that shearing force efficiently exerts on ice interposed between shafts, and ice is easily cracked. Accordingly, with more output shafts, ice is more easily broken.
It has been confirmed by the applicant's experiments that by making the shapes of second output shaft 15 and third output shaft 24 cross (+), and rotating second output gear 137 and third output gear 138 in the same direction, ice is broken into six pieces.
The cross sectional shape of second output shaft 15 and third output shaft 24 are not limited to the cross (+), but shapes sufficient to break ice by rotation, for example, a Y shape will do. Rotation is not always performed in the same direction.
As having mentioned above, the drive device of the automatic ice machine according to the invention has the structure of turning over the ice tray in which ice has been made by the first output shaft and crushing ice by the second output shaft, so that it is possible to offer less round and rock like ice, which satisfies needs of consumers.
The drive device may be structured to drive at least two output shafts with one motor, and is at low cost.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2003-424168 | Dec 2003 | JP | national |
