Leaf switch and ice making device using leaf switch

A leaf switch may include a cam body formed with a plurality of cam parts in a multistage shape and a plurality of leaf contact pieces which are extended toward the cam body and whose tip end sides of the plurality of leaf contact pieces are respectively abutted with the plurality of cam parts, and base end sides of the plurality of leaf contact pieces are held at the same height position. Further, an ice making device may include a water supply leaf switch for controlling water supply from a water-supply part to an ice tray, and a water supply amount adjust mechanism which includes an operation member that causes a leaf contact piece to deform to adjust a timing when the water supply switch is turned on or off. Further, an ice making device may include an ice detecting lever and a lever position detecting mechanism which detects ice amount in an ice storage part by detecting a position of the ice detecting lever.

CROSS REFERENCE TO RELATED APPLICATION

The present invention claims priority under 35 U.S.C. §119 to Japanese Application No. 2006-236882 filed Aug. 31, 2006, Japanese Application No. 2006-236888 filed Aug. 31, 2006, Japanese Application No. 2006-236901 filed Aug. 31, 2006, all of which are incorporated herein by reference.

FIELD OF THE INVENTION

An embodiment of the present invention may relate to a leaf switch in which a leaf contact piece is extended toward a cam body. Further, an embodiment of the present invention may relate to an ice making device which includes a water-supply switch for controlling water supply from a water-supply part to an ice tray. Further, an embodiment of the present invention may relate to an ice making device which includes an ice detecting lever for detecting ice amount in an ice storage part.

BACKGROUND OF THE INVENTION

In a leaf switch, a leaf contact piece which is extended toward a cam body is displaced by a cam part of the cam body to perform “ON” and “OFF” operation. In order to perform various switching operations by using the leaf switch, it is conceivable that a plurality of cam parts are formed in one piece of cam body in a multistage shape in a height direction which is perpendicular to its moving direction, and tip end sides of a plurality of leaf contact pieces which are linearly extended toward respective cam parts are abutted with the respective cam parts.

Further, an ice making device has adopted a structure in which a raking member is rotationally driven by a drive unit to discharge ice pieces from an ice tray. In this case, when an ice adhering force between the ice tray and ice pieces is large, ice pieces cannot be discharged. Therefore, an ice making unit provided with a heater at the vicinity of the ice tray has been adopted (see, for example, Japanese Patent Laid-Open No. 2003-143808).

Further, a detecting method for detecting ice amount in an ice storage part structured in an ice making device has been commonly known in which an ice detecting lever is driven in an approaching direction to the ice storage part to detect whether the ice detecting lever is disturbed by ice pieces in the ice storage part or not by using a lever position detecting mechanism. In order to structure the lever position detecting mechanism as described above, an operation of the ice detecting lever is required to be transmitted to a switch through a cam mechanism to detect a position of the ice detecting lever on the basis of “ON” and “OFF” operation of the switch. In this case, a cam face of the cam mechanism at a position corresponding to a timing when the switch performs the “ON” and “OFF” operation is formed in a slant face and thus a contact of the switch is gradually moved closer and moved away.

When a plurality of leaf contact pieces is linearly extended toward a plurality of cam parts formed in a multistage, height positions of the leaf contact pieces are different form each other and thus a structure of a contact piece holding part for holding the base end side of the leaf contact pieces becomes complicated. For example, in a case that a structure is to be adopted in which the contact piece holding part is formed with contact piece holding grooves and the leaf contact pieces are held in a state that the base end sides of the leaf contact pieces are inserted into the contact piece holding grooves, a plurality of contact piece holding grooves whose bottom parts are formed at different height positions is required. Further, when the base end sides of the leaf contact pieces which are inserted into the contact piece holding grooves are pressed in a height direction to be held, a pressure member in a complicated shape is required. Therefore, a lot of labor is required in assembling work of the leaf switch and a high degree of positional accuracy is difficult to be obtained for the leaf contact pieces.

In the above-mentioned ice making device, when a water-supply part is structured to the ice tray and a micro switch for controlling a water-supply time period from the water-supply part to the ice tray is provided, water supply can be also performed automatically. In addition, if a water-supply time period can be adjusted, amount of water supplied to the ice tray is adjusted. Therefore, size of ice can be changed arbitrarily. However, in order to adjust a timing of a micro switch which is turned on and off, mounting position of the micro switch is required to be changed and thus adjustment of water supply time period (amount of water supply) is not performed easily.

On the other hand, when a leaf switch is turned on and off by a cam face, a contact of the leaf switch gradually comes close or moves apart. Therefore, an unstable region is occurred which is not clearly distinguished between a state that contacts have come into contact with each other and a state that the contacts have moved apart from each other and thus various electric malfunctions may occur. Accordingly, when a leaf switch is used as a switch which is operated by a cam mechanism, electric malfunctions may be easily occurred. On the contrary, a micro switch is capable of turning immediate “ON” and “OFF”. However, a micro switch is expensive and largely affected by mounting error and operational position error and thus ice amount cannot be detected with a high degree of accuracy.

SUMMARY OF THE INVENTION

In view of the problems as described above, the present invention may provide a leaf switch which is capable of functioning and being mounted with a high degree of positional accuracy and that is easier to assemble.

Further, the present invention may provide an ice making device which is capable of easily adjusting a water-supply amount from a water-supply part to an ice tray.

Further, the present invention may provide an ice making device which is capable of preventing an unstable region from occurring which is not clearly distinguished between a state that contacts are contacted with each other and a state that the contacts are apart from each other even when a leaf switch is used for positional detection of an ice detecting lever.

Thus, according to a first embodiment of the present invention, there may be provided a leaf switch including a cam body which is formed with a plurality of cam parts in a multistage shape in a height direction perpendicular to a moving direction of the cam body, and a plurality of leaf contact pieces which are extended toward the cam body and whose tip end sides of the plurality of leaf contact pieces are respectively abutted with the plurality of cam parts. In the leaf switch, base end sides of the plurality of leaf contact pieces are held at the same height position.

In accordance with an embodiment of the present invention, a plurality of leaf contact pieces are extended toward the plurality of cam parts in a multistage shape of the cam body and are abutted with the plurality of cam parts. In addition, base end sides of the plurality of leaf contact pieces are held at the same height position. Therefore, the structure of a contact piece holding part for holding the base end sides of the leaf contact pieces can be simplified. Further, when a structure is to be adopted in which contact piece holding grooves are formed in a contact piece holding part and the leaf contact pieces are held in a state that their base end sides are inserted into the contact piece holding grooves, the contact piece holding grooves may be formed to have the same depth. Further, when the base end sides of the leaf contact pieces which are inserted into the contact piece holding grooves are to be held by being pressed in a height direction, the leaf contact pieces can be pressed with a flat plate and a pressure member in a complicated shape is not required. Therefore, assembling work of the leaf switch can be effectively performed and the leaf contact pieces can be disposed with a high degree of positional accuracy.

In accordance with an embodiment of the present invention, the plurality of leaf contact pieces include a leaf contact piece whose extending direction is bent at a middle position from its base end side to its tip end side.

In accordance with an embodiment of the present invention, the base end sides of the plurality of leaf contact pieces are formed in a strip shape and edges of the base end sides in a height direction facing each other are extended in parallel to each other.

In accordance with an embodiment of the present invention, the plurality of leaf contact pieces are held in a state that respective base end sides are respectively inserted into a plurality of contact piece holding grooves having a same depth.

In accordance with an embodiment of the present invention, the cam body and the plurality of leaf contact pieces are accommodated within a case body which is structured of a plurality of members superposed on each other in a height direction, and the base end sides of the plurality of leaf contact pieces are pressed in the height direction when the plurality of members of the case body is superposed on each other in the height direction.

In this case, it is preferable that a rigid circuit board, with which each of the plurality of the leaf contact pieces is electrically connected, is disposed to superpose on the base end sides of the plurality of the leaf contact pieces, and the base end sides of the plurality of leaf contact pieces are pressed in the height direction through the circuit board when the plurality of members of the case body is superposed on each other in the height direction. According to the structure as described above, the circuit board may directly contact with the leaf contact pieces and the circuit board is originally provided with a sufficient withstand voltage. Therefore, a separate pressure member having a high withstand voltage is not required.

Further, according to an embodiment of the present invention, there may be provided an ice making device including an ice tray, a water-supply part for supplying water to the ice tray, a water supply switch for controlling water supply from the water-supply part to the ice tray which is a leaf switch comprising a pair of leaf contact pieces and at least one of the pair of leaf contact pieces is driven by a cam member; and a water supply amount adjust mechanism which includes an operation member that causes at least one of the pair of leaf contact pieces to deform to adjust a timing when the water supply switch is turned on or off.

In accordance with an embodiment of the present invention, a leaf switch is used as a water supply switch. Therefore, even when the position of the entire leaf contact pieces is not changed, timings of turning on and off can be adjusted only by deforming the leaf contact piece. Accordingly, supply amount of water from the water-supply part to the ice tray can be adjusted easily.

In accordance with an embodiment of the present invention, one of the pair of leaf contact pieces is capable of being deformed by the water supply amount adjust mechanism and the other of the pair of leaf contact pieces is driven by the cam member, and a spaced distance of the pair of leaf contact pieces is adjusted by deforming the one of the pair of leaf contact pieces by the water supply amount adjust mechanism. According to the structure as described above, even when water-supply amount from the water-supply part to the ice tray is adjusted, a timing of the other of the leaf contact pieces which is driven by the cam member does not change and thus the water supply switch is surely operated.

In accordance with an embodiment of the present invention, a tip end side of the one of the pair of leaf contact pieces is deformed by the water supply amount adjust mechanism under a state that a base end side of the one of the pair of leaf contact pieces is fixed.

In accordance with an embodiment of the present invention, the water supply switch is disposed within an inside of the case body, and the operation part of the operation member is disposed at an outside of the case body. According to the structure as described above, water-supply amount can be adjusted from outside even when the case body is not disassembled.

In accordance with an embodiment of the present invention, a click mechanism for holding the operation member at an operated position is provided. According to the structure as described above, the operation member can be held at an operated position by the click mechanism and operating feeling can be enhanced.

In accordance with an embodiment of the present invention, the operation member includes a pinion member which is turnable around an axial line by an external operation, and a transmitting member having a teeth part which is capable of engaging with the pinion member. The transmitting member transmits the external operation for the pinion member to the leaf contact piece to deform the leaf contact piece.

In accordance with an embodiment of the present invention, a lock mechanism is provided for preventing the operation member from displacing during a period except when the external operation is performed. According to the structure as described above, the operation member is not mistakenly operated.

In accordance with an embodiment of the present invention, the lock mechanism permits turning of the pinion member when an external force is applied to displace the pinion member to one side in an axial line direction, and the lock mechanism prevents turning of the pinion member when the external force is released to displace the pinion member to the other side in the axial line direction.

In accordance with an embodiment of the present invention, a portion of the pinion member to which the external force is applied is structured as a movable part which is capable of being displaced to the one side in the axial line direction, and when the movable part is displaced to the one side in the axial line direction by an external pressing operation, engagement of the pinion member is released and, in this state, when an external turning operation is applied to the movable part, the entire pinion member is turned around the axial line and, when application of the external force to the movable part is released and the movable part is displaced to the other side in the axial line direction, the pinion member is locked. According to the structure as described above, the lock mechanism can be structured with a reduced number of parts.

In accordance with an embodiment of the present invention, the water supply switch and the operation member are disposed in an inside of the case body. According to the structure as described above, since the operation member is not protruded outside from the case body, the size of the ice making device can be reduced.

In accordance with an embodiment of the present invention, a contact piece holding part is formed in a member structuring the case body and the pair of leaf contact pieces are held by the contact piece holding part.

Further, according to an embodiment of the present invention, there may be provided an ice making device including an ice storage part, an ice detecting lever which is driven in directions moving close to and moving apart from the ice storage part, and a lever position detecting mechanism which detects ice amount in the ice storage part by detecting a position of the ice detecting lever. The lever position detecting mechanism includes a driving member which is connected with the ice detecting lever, a driven member which is driven by the driving member with a play, a transmitting member whose positions are changed by a cam face of the driven member, and a leaf switch including a leaf contact piece which is pressed by the transmitting member to be elastically deformed. When the driving member is moved in one direction, an abutting portion of the transmitting member to the driven member is changed from a low portion to a high portion through a slant face portion of the cam face to cause the transmitting member to elastically deform the leaf contact piece and, in a case that the driving member is moved to the other direction, when the transmitting member is urged by the leaf contact piece to be displaced, the transmitting member presses the slant face portion to cause the leaf switch to perform a switching operation at a timing earlier than that of the driven member which is driven by the driving member.

In accordance with the embodiment of the present invention, the driven member is driven with a play by the driving member. Therefore, after the driving member has moved in one direction, when the driving member is moved in the other direction, the driven member is not immediately driven. Instead, the leaf contact piece applies an urging force which is going to restore from an elastically deformed state to the transmitting member. Therefore, even before the driven member is driven by the driving member, the transmitting member presses the slant face portion formed on the driven member to displace the driven member. Accordingly, even before the driven member is driven by the driving member, the leaf contact piece can be restored from the elastically deformed state and thus a switching operation of the leaf switch is immediately performed. As a result, even when an operation is transmitted to the leaf switch through the cam mechanism, an unstable region does not occur which is not clearly distinguished between a state that contacts of the leaf switch are contacted with each other and a state that the contacts are apart from each other and thus electric malfunctions do not occur.

In accordance with an embodiment of the present invention, a position of the ice detecting lever where the transmitting member is abutted with the slant face portion of the cam face is set in a position for determining whether or not ice amount in the ice storage part is in a full state or in a shortage state.

In accordance with an embodiment of the present invention, the driving member is driven and turned by a drive source, and a transmission part for transmitting movement of the driving member to the driven member is formed between the driving member and the driven member with a prescribed space therebetween so as to have a play in a circumferential direction.

In accordance with an embodiment of the present invention, the driving member is provided with a rotation shaft, and the driven member is a driven ring which surrounds around the rotation shaft of the driving member, and the transmission part is structured of a projection, which is formed on an outer peripheral face of the rotation shaft, and a recessed part in the driven ring which is formed on an inner circumferential edge of a hole of the driven ring into which the rotation shaft is inserted, and the projection is located on an inner side of the recessed part of the driven ring.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An ice making device to which the present invention is applied will be described below with reference to the accompanying drawings.

FIG. 1is a perspective view showing an ice making device in accordance with an embodiment of the present invention.FIG. 2(A)is a perspective view showing a raking member,FIG. 2(B)is a perspective view showing an ice tray, andFIG. 2(C)is a perspective view showing a guide member, which are used in the ice making device shown inFIG. 1.FIG. 3(A)is a front view showing the ice making device shown inFIG. 1,FIG. 3(B)is a cross-sectional view showing a state where the raking member in the ice making device is located at a home position, andFIG. 3(C)is a cross-sectional view showing a state where the raking member has turned from the home position.

InFIG. 1,FIGS. 2(A) through 2(C)andFIGS. 3(A) through 3(C), an ice making device1in accordance with an embodiment is a device in which ice pieces are successively manufactured within a refrigerator or a freezer and manufactured ice pieces are automatically discharged to an ice storage part1awhich is disposed on a lower side. The ice making device1includes an ice making unit2for manufacturing ice pieces and a drive unit3(drive control part) for controlling a raking operation and the like of the ice pieces. An ice detecting lever60formed in a roughly L-shape is extended toward the lower ice storage part1afrom the drive unit3. The ice making unit2includes an ice tray21, a water-supply part22disposed on a side (rear side) of the ice tray21for supplying the ice tray21with water, a raking member23for raking out the ice pieces manufactured in the ice tray21, a guide member24for guiding the ice pieces which has been raked out by the raking member23to the ice storage part1alocated downward of the ice tray21, and an end plate25structuring a right side face of the ice tray21.

The ice tray21is made of aluminum on which surface treatment such as coating or alumite treatment is performed. A plurality of ice making grooves215(recessed part for ice making) is dividedly formed on an upper face of the ice tray21by partition plates218. Water supplied from the water-supply part22is respectively stored in the plurality of ice making grooves215to be frozen. A heater26for heating a bottom face of the ice tray21when the ice pieces are to be discharged from the ice tray21is disposed on a bottom face of the ice tray21. The heater26is integrated with the ice tray21by caulking or the like. Two terminal parts262made of rubber for the heater26are protruded from a left side face part of the ice tray21and a terminal261is protruded from a tip end face of the respective two terminal parts262. A temperature detecting part219is formed in an area between the two terminal parts262of the ice tray21and a thermostat is abutted with the temperature detecting part219to monitor temperature of the ice tray21.

The water-supply part22is disposed on an opposite side (rear side) to the side where the ice pieces are discharged (front side) with respect to the ice tray21and is provided with a water-supply port221which opens in a rear wall of the ice tray21. Water is supplied from a hose228to the water-supply part22and a water-supply valve220is provided at a midway position of the hose as schematically shown inFIG. 3(B).

The raking member23is provided with a rotation shaft231which is laterally extended at an upper position of the ice tray21and a plurality of raking parts232which are protruded from the rotation shaft231in a claw-like shape in the same direction. The respective raking parts232are provided so as to correspond to the respective ice making grooves215. A right side end part of the rotation shaft231is rotatably supported by a cutout part211which is formed at an edge part of a right side face part217of the ice tray21and is rotatably supported by a shaft hole251formed in the end plate25. Further, a flange part239formed at the right side end part of the rotation shaft231is abutted with an inner side face of the end plate25and thus movement of the rotation shaft231toward the right side is restricted. On the other hand, the other end of the rotation shaft231is formed in a D-cut (D-shaped) portion230and, as shown inFIG. 3(A), the D-cut portion230is connected with a rotary cam body55(cam body) disposed within the drive unit3.

In accordance with an embodiment, a position of the raking part232shown inFIG. 3(B)is set to be a home position. In the home position, the raking parts232are set in a state that the raking parts232are inclined on an opposite side to the water-supply port221with respect to the rotation shaft231. From this state, the rotation shaft231is turned in a direction shown by the arrow “A” to reach to a position shown inFIG. 3(C). During this movement, the raking parts232cause ice pieces in the ice making grooves215to move up from the ice tray21. The ice pieces moved up from the ice tray21by the raking parts232slide on the raking parts232and an upper face of the guide member24to fall to the ice storage part1afrom a front side of the ice tray21. In this case, the ice pieces moved up from the ice tray21may not fall to the ice storage part1aby only the raking parts232which have reached to the state shown inFIG. 3(C)from the state shown inFIG. 3(B). However, the ice pieces in the ice tray21has completely fallen to the ice storage part1abefore the raking parts232are returned to the home position shown inFIG. 3(B).

FIGS. 4(A) through 4(D)andFIGS. 5(A) through 5(D)are explanatory circuit diagrams showing a schematic electrical structure of a drive unit of the ice making device shown inFIG. 1.FIG. 6is a timing chart showing an operation of the ice making device shown inFIG. 1.

A mechanical structure of a drive unit3of the ice making device1in accordance with an embodiment will be described in detail below with reference toFIG. 7,FIG. 8(A)and the like. The drive unit3of the ice making device1in this embodiment includes, as shown inFIG. 4(A), a thermostat91for monitoring temperature of the ice tray21, a motor5for driving the rotation shaft231, a main switch72for performing open/close operation in conjunction with rotational operation of a rotary cam body55shown inFIG. 3(A), a water-supply switch73for controlling the water-supply valve220in conjunction with the rotational operation of the rotary cam body55, an ice detecting switch71for monitoring whether the ice storage part1ais in a shortage state or in a full state of ice pieces, and a fuse1g. Further, the ice making device1is provided with a transmission mechanism for transmitting a rotary output of the motor5to the rotary cam body55, a torque limiter disposed at a midway position of the transmission mechanism and the like as described below.

Next, a basic operation of the ice making device1will be described below based on the chart shown inFIG. 6. First, after water has been supplied to the ice tray21from the water-supply port221, an ice making operation is started in the ice tray21. During this time, power supply to the motor5and the heater26is stopped and the raking parts232are stopped at the home position where the raking parts232are inclined on an opposite side to the water-supply port221as shown inFIG. 3(B). In this state, as shown inFIG. 4(A), the main switch72is in a first state where the thermostat91and the water-supply switch73are in an “OFF” state. In addition, the ice detecting switch71is located at a position showing an ice shortage state (first state).

After that, at the time of “T0”, when a monitoring result of the thermostat91for the ice tray21indicates that a temperature of the ice tray21has become equal to a predetermined temperature or lower, as shown inFIG. 4(B), the thermostat91is turned to be in an “ON” state and energization to the motor5and the heater26is started. As a result, the rotary cam body55is turned and thus the raking member23is started to turn in a direction shown by the arrow “A” inFIG. 3(B)and the heater26starts to warm the ice tray21.

Next, at the time of “T1”, the main switch72is switched to a second state as shown inFIG. 4(C). However, even when the main switch72is switched to the second state, the energization to the motor5and the heater26is continued. Therefore, the raking member23is driven by the motor5and tip end portions of the raking parts232are abutted with upper faces of ice pieces manufactured in the ice tray21. However, at this time, the temperature of the ice tray21may be low and thus an ice adhering force of the ice piece in the ice tray21is large. Therefore, turning of the raking member23is prevented by the ice pieces in the ice tray21and the tip end portions of the raking parts232are stopped in a state where that the tip end portions of the raking parts232are abutted with the upper faces of the ice pieces in the ice tray21. In accordance with an embodiment, a torque limiter is disposed at a midway position of a power transmission route from the motor5to the raking member23. Therefore, the motor5is capable of continuing to rotate while turning of the raking member23is stopped, and thus a torque limited by the torque limiter8continues to act on the ice pieces.

When the ice pieces have been separated from the ice tray21by applying heat with the heater26, the raking member23connected with the rotary cam body55starts to turn in a direction where the ice pieces are raked out and then an ice detecting operation is performed. At the time of “T2”, a tip end portion of the ice detecting lever60firstly moves upward from the ice storage part1a. As a result, as shown inFIG. 4(D), the ice detecting switch71is temporarily switched from the first state to the second state. At approximately same time, discharge of the ice pieces is started and, after all of the ice pieces have fallen into the ice storage part1a, at a time of “T3”, the tip end portion of the ice detecting lever60moves down toward the ice storage part1aagain. At this time, when the ice storage part1ais in an ice shortage state, the tip end portion of the ice detecting lever60is capable of being moved downward and thus, as shown inFIG. 4(C), the ice detecting switch71is returned to the first state from the second state.

Next, at the time of “T4”, when a temperature of the ice tray21exceeds a predetermined temperature, a monitoring result of the thermostat91for the ice tray21is, as shown inFIG. 5(A), changed to an “OFF” state and energization to the heater26is stopped. However, energization to the motor5is continued.

Next, at the time of “T5”, as shown inFIG. 5(B), when the water-supply switch73is changed to an “ON” state, the water-supply valve220is changed to an open state to supply water to the ice tray21through the water-supply port221. In this case, since a resistance value of the heater26is small, the heater26is utilized as a part of electric wiring when the water-supply valve220is energized. At this time, the raking parts232have already passed near and an upper side of the water-supply port221and are located on a side in an inclined state which is opposite to the side where the water-supply port221is disposed.

Next, at the time of “T6”, as shown inFIG. 5(C), since the water-supply switch73is changed to an “OFF” state; the water-supply valve220is changed to a closed state and water-supply to the ice tray21through the water-supply port221is stopped. Next, at the time of “T7”, power supply to the motor5is stopped and the raking parts232are stopped at the home position where the raking parts232are inclined on the opposite side to the water-supply port221. In the meantime, the main switch72is returned to the first state as shown inFIG. 4(A). After that, manufacturing of ice pieces is performed in the ice tray21again and then the above-mentioned operation is repeated.

In the embodiment described above, after the tip end portion of the ice detecting lever60has been moved upward from the ice storage part1aat the time of “T2” and then, its tip end portion is going to move downward to the ice storage part1aagain at the time of “T3”. In this case, when the ice storage part1ais in an ice full state, the tip end portion of the ice detecting lever60cannot move downward and thus the ice detecting switch71remains to be in the second state as shown inFIG. 4(D). However, also in this state, energization to the heater26and the motor5is continued and thus operation for returning to the home position is performed. In subsequent operations, when the ice storage part1ais in the ice full state, as shown inFIG. 5(D), the ice detecting switch71remains to be in the second state. Therefore, even when a temperature of the ice tray21becomes equal to a predetermined temperature or lower to cause the thermostat91to be changed to an “ON” state, energization to the heater26and the motor6is not performed. Accordingly, after quantity of ice pieces in the ice storage part1ahas been reduced and the ice detecting switch71is changed to the first state from the second state, energization to the heater26and the motor6is started.

As described above, in the ice making device1in accordance with this embodiment, ice pieces can be successively manufactured and the ice pieces manufactured can be automatically discharged to the ice storage part1awhich is disposed downward. Further, ice quantity is detected in the ice storage part1aand, when the ice storage part1ais in an ice full state, discharging of ice pieces to the ice storage part1ais not performed and thus the ice pieces do not overflow from the ice storage part1a.

Further, in this embodiment, when the raking parts232are passed through near the water-supply port221and, in addition, passed through above the rotation shaft31and then reached to a position where the raking parts232are inclined on an opposite side to the water-supply port221, the drive unit3starts to supply water from the water-supply port221to the ice tray21. Therefore, a state is avoided where water is splashed on the raking parts232at the time of water-supply to cause the water to be frozen and, as a result, the ice tray21and the raking parts232are prevented to be frozen with each other.

Further, since the initial position, i.e., the home position of the raking parts232is set on an opposite side to the side where the water-supply port221is arranged with respect to the rotation shaft231, the water-supply part22is not disposed near the raking parts232which are stopped at the home position. Therefore, when confirmation of an operation of the raking member23is performed by manually pressing the raking parts232from an upper side to turn it in the direction shown by the arrow “A”, the operation is not disturbed by the water-supply part22and thus the operation can be easily confirmed.

Further, since the home position of the raking parts232is set on the opposite side to the side where the water-supply port221is arranged with respect to the rotation shaft231, when the raking parts232are depressed, the raking member23is turned so as to rake out in the direction shown by the arrow “A” and thus the operation can be easily confirmed. In other words, as a comparison example, when the home position of the raking parts232are set, for example, at a position shown inFIG. 3(C), in order to turn the raking member23in the direction as shown by the arrow “A”, it is required that a finger is inserted between the raking parts232to turn it up. However, according to the embodiment of the present invention, the troublesome operation as described above is not required.

FIG. 7is an explanatory view showing the inner case which is used in the drive unit and structural members disposed in the inner case in the ice making device in accordance with the embodiment.FIG. 8(A)is a side view showing a rotary cam body which is shown inFIG. 7.

As shown inFIG. 3(A), the drive unit3is provided with a case body4. The motor5, the main switch72structured of leaf switches, the water-supply switch73structured of leaf switches, the ice detecting switch71structured of leaf switches and the like which are described with reference toFIG. 4(A)are disposed in the inside of the case body4. In this embodiment, the case body4includes an inner case41formed in a rectangular measure shape, a base plate42(first partition wall) and an outer case43formed in a rectangular measure shape. The case body4is formed by superposing edge parts of the inner case41and the outer case43on each other from both the right and left sides so as to sandwich the base plate42. In this state, a first space46is partitioned and formed between the inner case41and the base plate42and a second space47is partitioned and formed between the outer case43and the base plate42. The first space46and the second space47are respectively used for disposing following mechanisms and the like.

As shown inFIG. 7, the thermostat91is fixed at a bottom part of the inner case41in the first space46between the inner case41and the base plate42. Further, in the ice making device1in this embodiment, as shown inFIG. 2(B), terminal parts262(engagement part for connection), which are made of an electrically insulator such as rubber, of the heater26are protruded from the ice tray21toward the drive unit3. Further, as shown inFIG. 7, the case body4of the drive unit3is formed with recessed parts411(engaged portion for connection) which open toward an outer side of the inner case41at the bottom part of the inner case41on both side positions of the thermostat91. A through hole412is formed in the back of the recessed part411. Further, a connection terminal92is disposed at the bottom part of the inner case41so as to expose in the through hole412. Therefore, after the drive unit3and the ice making unit2have been respectively assembled, the terminal parts262protruding from the ice tray21are fitted to the recessed parts411of the inner case41and, as a result, the ice making unit2and the drive unit3are connected with each other and the terminals261of the heater26are electrically connected with the connection terminals92at the fitting portions of the terminal parts262to the recessed parts411. Further, an earth (ground) member45is disposed on an outer side of the bottom part of the inner case41at a position which is capable of abutting with the ice tray21. When a portion where the earth member45is disposed is fixed to the ice tray21with a metal screw for earth (ground) connection in the inner case41, ground connection to the ice tray21can be performed. In this state, since the thermostat91is abutted with a temperature detecting part219of the ice tray21, the temperature of the ice tray21can be monitored. In addition, when the ice making unit2is connected with the drive unit3, the “D”-shaped portion230of the rotation shaft231is fitted into a hole formed in “D”-shape of the rotary cam body55which is disposed in the inside of the case body4. Therefore, the drive unit3and the ice making unit2are mechanically connected with each other.

As described above, in the ice making device1in accordance with this embodiment, when the ice making unit2is to be connected with the drive unit3, members required to be electrically connected are only the terminals261of the heater26and the connection terminals92. Therefore, the drive unit3and the ice making unit2are connected with each other only by fitting the terminal parts262(engagement part for connection) protruding from ice tray21to the recessed parts411(portion to be engaged for connection) of the inner case41, and the terminals261of the heater26and the connection terminals92are automatically connected with each other. Further, when the ice making unit2is to be connected with the drive unit3, members required to be mechanically connected are only the rotation shaft231and the rotary cam body55and, when the ice making unit2is connected with the drive unit3, the “D”-shaped portion230of the rotation shaft231is automatically fitted into the connection hole557of the rotary cam body55whose inlet portion is formed in a “D”-shape in cross-section.

Therefore, after the ice making unit2and the drive unit3have been separately assembled, the ice making device1can be assembled only by connecting the ice making unit2with the drive unit3. Accordingly, assembling steps can be simplified in comparison with a case that members for structuring the drive unit are successively and separately assembled to the ice making unit2.

Further, according to the embodiment of the present invention, the ice making unit2and the drive unit3are connected with each other after the ice making unit2and the drive unit3have been separately manufactured. Therefore, different from a comparison method in which, after respective members are successively mounted on the ice tray21to complete the drive unit, a heater is mounted on the ice tray, in the embodiment of the present invention, fragments and dirt sticking to the ice tray21which structures the ice making unit2can be reduced and thus sanitary quality in the ice making device1is improved.

In addition, after the drive unit3and the ice tray21have been connected, it is difficult that the ice tray21is integrated with the heater26by caulking or insert-molding. However, according to this embodiment, after the ice tray21and the heater26have been integrated with each other by caulking or insert-molding, the ice making unit2is assembled and, after that, the ice making unit2can be connected with the drive unit3.

Further, in the ice making device1in accordance with this embodiment, the earth (ground) member45is disposed on the outer side of the inner case41at the position where the earth member45is capable of abutting with the ice tray21. Therefore, when the portion of the inner case41where the earth member45is disposed is fixed to the ice tray21with a metal screw having electroconductivity, grounding treatment of the ice making device1can be performed easily.

As shown inFIG. 3(A), one side portion of the rotary cam body55is disposed at the bottom part of the inner case41in the first space46formed between the inner case41and the base plate42. An upper end side, i.e., the other side of the rotary cam body55is protruded into the second space47formed between the base plate42and the outer case43through the through hole421formed in the base plate42.

In the first space46formed between the inner case41and the base plate42, as shown inFIG. 7, the motor5is disposed at the bottom part of the inner case41on a side of the rotary cam body55. An AC synchronous motor is, for example, used as the motor5. A transmission mechanism50for transmitting rotation of the motor5to the rotation shaft231of the ice making unit2is formed in the first space46. The transmission mechanism50includes a rotor pinion51which is rotatably supported by a fixed shaft of the motor5, a torque limiter8provided with an outer teeth gear502(input part) having a large diameter which is engaged with the rotor pinion51, a chipped tooth gear503structuring an output part of the torque limiter8, a gear body52provided with an outer teeth gear504having a large diameter which is driven by the chipped tooth gear503, a gear body53provided with an outer teeth gear506having a large diameter which engages with an outer teeth gear (not shown) having a small diameter of the gear body52, and the rotary cam body55provided with an outer teeth gear54having a large diameter which is engaged with an outer teeth gear507having a small diameter of the gear body53. The tip end portion of the fixed shaft of the motor5is supported by the base plate42. Support shafts which rotatably support the torque limiter8, the gear body52and the gear body53are supported by an end plate5aof the motor5and the base plate42. The rotary cam body55is rotatably supported by the bottom part of the inner case41and the base plate42.

As shown inFIG. 8(A), the rotary cam body55is provided with a cylindrical part551extending downward, i.e., the ice making unit2side from the outer teeth gear54. The cylindrical part551is formed with a coupling hole557in a “D”-shape in cross section at its inlet portion. The “D”-shaped portion230of the rotation shaft231is fitted into the coupling hole557to transmit rotation of the rotary cam body55to the rotation shaft231.

FIG. 9(A)is a plan view showing the torque limiter which is provided in the ice making device in accordance with an embodiment of the present invention andFIG. 9(B)is its exploded perspective view.

In the ice making device1in this embodiment, when the raking parts232formed on the rotation shaft231of the ice making unit2is going to move to rake ice pieces formed in the ice tray21out, the ice pieces may not be separated from the ice tray21immediately after heating is started by the heater26. In this state, when the rotation shaft231is turned to going to rake the ice pieces in the ice tray21out by the raking parts232, a large load is applied to the raking parts232by unmoved ice pieces. Therefore, an excessive load is applied to the transmission mechanism50for transmitting a rotary force of the motor5to the rotation shaft231and thus a gear structuring the transmission mechanism50may be damaged. In order to prevent the problem described above, in this embodiment, as shown inFIG. 7, the torque limiter8which will be described below is structured on a motor side of the transmission mechanism50.

As shown inFIG. 7andFIGS. 9(A) and 9(B), the torque limiter8includes a gear body80(first member) made of resin, a cup-shaped sliding member84(second member) made of resin, and a coil spring85(ring-shaped urging member). The gear body80is provided with a large diameter circular plate part81formed with the outer teeth gear502. A small diameter cylindrical part82is formed upright at a center portion of an upper face of the large diameter circular plate part81and a large diameter cylindrical part83is formed so as to surround the small diameter cylindrical part82. The gear body80is formed with a shaft hole811so as to penetrate through the large diameter circular plate part81and the small diameter cylindrical part82. A support shaft (not shown) whose both ends are supported by the end plate5aof the motor5and the base plate42is fitted to the shaft hole811. Therefore, the gear body80is capable of being driven by the rotor pinion51to be rotated around the support shaft.

The sliding member84is formed in a cup shape which opens toward the gear body80. The sliding member84includes an upper base part847(bottom plate part) and a cylindrical drum part845extending perpendicularly downward from an outer peripheral edge of the upper base part847. Therefore, in a state where the sliding member84is assembled on the gear body80, the cylindrical drum part845of the sliding member84is fitted so as to surround a circumferential face of the large diameter cylindrical part83of the gear body80. The upper base part847of the sliding member84is formed in a multi-stage shape including a large diameter part841, a middle diameter part842and a small diameter part843which are formed in this order. A chipped tooth gear503is formed on a side face of the small diameter part843. A hole into which the small diameter cylindrical part82of the gear body80is fitted is formed in the inside of the large diameter part841and the middle diameter part842. The small diameter part843is formed with a shaft hole840into which a support shaft penetrating through the small diameter cylindrical part82is fitted. Therefore, the sliding member84is also rotatable around the support shaft. In this case, the sliding member84is supported by the small diameter cylindrical part82.

An inner diameter dimension of the cylindrical drum part845of the sliding member84is set to be a little larger than the outer diameter dimension of the large diameter cylindrical part83of the gear body80to have a specified clearance between them. The cylindrical drum part845of the sliding member84is formed with three cutout parts84awhich are extended in an axial direction from its tip end portion with an equal angular interval. Therefore, the cylindrical drum part845is divided into three elastic plate parts846in a tongue shape which are separated in a circumferential direction by the cutout parts84a. Accordingly, in a state that the sliding member84is assembled on the gear body80such that the cylindrical drum part845surrounds around the large diameter cylindrical part83of the gear body80, when the coil spring85is mounted around the cylindrical drum part845(elastic plate parts846), the elastic plate parts846are elastically deformed to an inner side or a center side to abut with the outer circumferential face of the large diameter cylindrical part83. As a result, when the gear body80is rotated and a large load is not applied to the sliding member84, the sliding member84is rotated together with the gear body80. On the contrary, when the gear body80is rotated but a large load is applied to the sliding member84, slip occurs between the elastic plate parts846and the large diameter cylindrical part83and thus rotation of the gear body80is not transmitted to the sliding member84.

The coil spring85is mounted only at a lower end portion of the cylindrical drum part845(tip end portions of the elastic plate parts846). The cutout part84ais extended to a root portion of the large diameter part841in the upper base part847of the sliding member84, and the upper base part847is also divided into three portions by the cutout parts84ato form base parts of the elastic plate part846. Therefore, the elastic plate part846of the sliding member84is formed in a perpendicularly bent shape from the upper base part847and, in addition, an axial dimension of the cylindrical drum part845is set to be longer than a dimension in a radial direction of the upper base part847. Accordingly, the elastic plate part846has a high rigidity in the circumferential direction but its rigidity in the radial direction is low and thus the elastic plate part846can be elastically deformed easily toward a center side. Further, in order to make the elastic plate parts846easily and elastically deformed on a center side, the cutout part84awhich is formed from the tip end of the cylindrical drum part845to a middle portion of the upper base part847is formed such that a length of the cutout part formed in the cylindrical drum part845is longer than a length of the cutout part formed in the upper base part847.

As described above, in the ice making device1in this embodiment, the torque limiter8is structured at a first stage of the transmission mechanism50(on the side nearer to a drive source in the transmission mechanism50) and thus a torque applied to the torque limiter8is small.

In the sliding member84of the torque limiter8, the cutout part84ais formed from the cylindrical drum part845to the upper base part847. Therefore, since the length of the elastic plate part846is long, the elastic plate part846has a high rigidity in the circumferential direction but has a low rigidity in the radial direction. Accordingly, the elastic plate parts846are easily bent resiliently when the coil spring85is mounted around the cylindrical drum part845. As a result, rigidity of the elastic plate part846does not exert large influence on the friction torque and the friction torque is roughly determined only by an urging force of the coil spring85. Therefore, when dimension of the gear body80made of resin and dimension of the cup-shaped sliding member84made of resin are varied, or even when rigidity of the elastic plate part846is varied with an elapse of time or due to ambient temperature, the variation of the friction torque is reduced. Especially, the ice making device1in this embodiment is used in a refrigerator or in a freezer and, on the other hand, the ice making device1is often warmed by the heater26. Therefore, the rigidity of the elastic plate part846made of resin is easily varied but, even in this case, the torque limiter8is operated surely.

In this embodiment, only the tip end portions of the elastic plate parts846are pressed by the coil spring85toward the outer circumferential face of the large diameter cylindrical part83and thus the elastic plate parts846are easily deformed. Moreover, the torque limiter8is simply structured and thus effect of accuracy of its structural parts is small. Further, when a spring having a small spring constant can be used as the coil spring85so as to be elastically deformed largely, the torque limiter8is surely operated even though part accuracy of the sliding member84is low. In addition, since the coil spring85can provide a stable urging force, a stable friction torque is obtained.

In this embodiment, it is structured that the large diameter part841, the middle diameter part842and the small diameter part843are superposed in this order on the upper base part847of the sliding member84. A hole into which the small diameter cylindrical part82of the gear body80is fitted is formed on an inner side of the large diameter part841and the middle diameter part842. Further, the small diameter part843is formed with a shaft hole840into which the support shaft penetrating through the small diameter cylindrical part82is fitted. Therefore, the sliding member84and the gear body80are supported by the common support shaft and the sliding member84is rotated in a state that the sliding member84is supported by the small diameter cylindrical part82of the gear body80. Accordingly, the sliding member84and the gear body80are rotated with surely maintaining a coaxial state.

FIG. 10is an explanatory view showing the base plate used in the drive unit and structural members which are disposed on the outer case side of the base plate in the ice making device in the embodiment.

In this embodiment, an ice detecting mechanism6for detecting ice quantity in the ice storage part1athrough the ice detecting lever60shown inFIG. 1is structured by utilizing the first space46between the inner case41and the base plate42and the second space47between the base plate42and the outer case43, which are shown inFIG. 3(A).

In this embodiment, the ice detecting mechanism6includes generally, an ice detecting lever drive mechanism65as shown inFIG. 7which is structured by utilizing the first space46between the inner case41and the base plate42, and an ice detecting lever position detecting mechanism75which is structured by utilizing the second space47between the base plate42and the outer case43, and an ice detecting switch71which is structured by utilizing the second space between the base plate42and the outer case43, which are shown inFIG. 10. “ON” and “OFF” operations of the ice detecting switch71are performed by the ice detecting lever position detecting mechanism75.

As shown inFIG. 7andFIG. 8(A), the lever drive mechanism65includes a cam part552formed around a cylindrical part551which is formed on a lower end side of the rotary cam body55, a first drive lever61which is driven by a cam face of the cam part552to move the ice detecting lever60, a coiled torsion spring66which urges the first drive lever61, and a second drive lever62which holds an end part of the ice detecting lever60.

The first drive lever61is provided with a pawl part611capable of abutting with the cam part552, a cylindrical support shaft612extending in an axial direction, and a transmitting part614which is located on an opposite side to the pawl part611with respect to the support shaft612. A “U”-shaped cutout part613is formed in the transmitting part614. Therefore, when the rotary cam body55is turned by rotation of the motor5to turn the cam part552, the pawl part611is pushed by the cam part552and the first drive lever61is turned around the support shaft612by a specified angle in a direction shown by the arrow “C1” inFIG. 7against an urging force of the coiled torsion spring66. Further, when a small diameter portion of the cam face abuts with the pawl part611, the first drive lever61is turned around the support shaft612in a reverse direction shown by the arrow “C2” by the urging force of the coiled torsion spring66to return to its original position.

The second drive lever62is provided with a cylindrical part621having a slit621afor holding an end part of the ice detecting lever60, a transmitting projection623which is protruded from a side face of the cylindrical part621, and a small projection622which is protruded from the side face of the cylindrical part621on an opposite side to the transmitting projection623. A pin623awhich is protruded from an under face of the transmitting projection623is fitted into a “U”-shaped cut-out part613which is formed in the first drive lever61. Therefore, when the first drive lever61is turned in the direction shown by the arrow “C1”, the second drive lever62is turned around the cylindrical part621in the direction shown by the arrow “D1”. On the other hand, when the first drive lever61is turned in the direction shown by the arrow “C2”, the second drive lever62is turned around the cylindrical part621in the direction shown by the arrow “D2”. As a result, the ice detecting lever60is driven. In accordance with this embodiment, the base plate42is formed with a stopper629a, which prevents the transmitting projection623of the second drive lever62from turning more than a prescribed position in the direction shown by the arrow “D2”, and a stopper629bwhich prevents the transmitting projection623from turning more in the direction shown by the arrow “D1”.

A flat spring63is disposed at a side position of the cylindrical part621and, when the ice detecting lever60is lifted upward with a manual operation, the small projection622of the second drive lever62goes over a projected part63aof the flat spring63to maintain a lifted state of the ice detecting lever60. As a result, the ice making device1becomes to be a similar state to the ice full state and thus an operation of the ice making device1is stopped.

As shown inFIG. 10, an upper half portion of the cylindrical part621of the second drive lever62is penetrated through the base plate42and located at a second space47between the base plate42and the outer case43. The ice detecting lever position detecting mechanism75includes a projection625(engagement part) that is formed on the outer peripheral face of an upper end portion of the cylindrical part621(rotation shaft) in the second drive lever62(driving member), a driven ring751(driven member) which is put on around the upper end of the cylindrical part621on the base plate42, and a pressing lever753(transmitting member) whose positions are changed by a protruded part752which is protruded from an outer peripheral face (cam face) of the driven ring751. The pressing lever753is provided with a cylindrical part753awhich is fitted to a protruded part that is formed in the base plate42, a connection part753bwhich is extended from the cylindrical part753a, a first protruded part753cwhich protrudes to the driven ring751side from a tip end portion of the connection part753b, and a second protruded part753dwhich protrudes to an opposite side to the first protruded part753cfrom the tip end part of the connection part753b.

In the ice detecting lever position detecting mechanism75, a cut-out part755(recessed part) which is extended in a peripheral direction is formed on a rear face side of the protruded part752of the driven ring751and on an inner peripheral side of a hole through which the cylindrical part621is penetrated. The projection625that is formed on the cylindrical part621of the second drive lever62is located within the inside of the cut-out part755with a constant play to end parts755aand755bin the peripheral direction of the cut-out part755. Therefore, a transmission part through which movement of the second drive lever62is transmitted to the driven ring751is formed between the second drive lever62and the driven ring751so as to be apart from each other in the peripheral direction by a prescribed dimension.

In the ice detecting lever position detecting mechanism75structured as described above, when the second drive lever62is turned in the direction of the arrow “D1” (when the ice detecting lever60is lifted), the movement of the second drive lever62is transmitted to the driven ring751by the projection625which abuts with the end part755blocated on the side shown by the arrow “D1” in the peripheral direction of the cut-out part755. As a result, the driven ring751is turned in the direction shown by the arrow “D1” in conjunction with the second drive lever62. Accordingly, the first protruded part753cof the pressing lever753is moved from a state, that the first protruded part753cabuts with a peripheral face (low portion of the driven member) of the driven ring751where the protruded part752is not formed, to a state that the first protruded part753cabuts with a slant face752dof the protruded part752, which is just before abutting with an outer peripheral face of the protruded part752(high portion of the driven member). As a result, the pressing lever753is turned around the cylindrical part753ain a direction shown by the arrow “E1” and the second protruded part753dcauses the ice detecting switch71to perform “ON” and “OFF” operation.

In this embodiment, the ice detecting switch71is a leaf switch which is comprised of three leaf contact pieces711,712and713. The pressing lever753abuts with only the leaf contact piece711among three leaf contact pieces711,712and713to cause it to move. More specifically, when the second protruded part753dof the pressing lever753is in a non-abutting state, the leaf contact piece711is abutted with an end part713aof the leaf contact piece713which is extended to an opposite side to the leaf contact piece711with respect to the leaf contact piece712so as to face the leaf contact piece711and thus the leaf contact piece711and the leaf contact piece713are in a contact state with each other. On the other hand, when the leaf contact piece711is pressed by the second protruded part753dof the pressing lever753, the leaf contact piece711is deformed to a side of the leaf contact piece712and thus the leaf contact piece711is moved apart from the end part713aof the leaf contact piece713to be in a contact state with the leaf contact piece712.

In the ice detecting mechanism6structured as described above, the leaf contact piece711is abutted with the end part713aof the leaf contact piece713before the motor5is started and rotated. In order to detect an ice quantity in the ice storage part1a, when the rotary cam body55is turned by the motor5to turn the first drive lever61in the direction shown by the arrow “C1”, the second drive lever62is turned around the cylindrical part621in the direction shown by the arrow “D1”. As a result, the ice detecting lever60is turned as shown by the arrow “F1” inFIGS. 3(A) and 3(B), and its end part goes up. In this case, the second drive lever62is turned in the direction shown by the arrow “D1” and the driven ring751is also turned in the direction shown by the arrow “D1”. Therefore, the protruded part752of the driven ring751is abutted with the first protruded part753cof the pressing lever753to cause the pressing lever753to turn in the direction shown by the arrow “E1” and a state is obtained where the leaf contact piece711is contacted with the leaf contact piece712. Further, in a state that the pressing lever753is abutted with the protruded part752of the driven ring751, the leaf contact pieces711and712are stably contacted with each other.

When the rotary cam body55is further turned by the rotation of the motor5, the first drive lever61is turned in a reverse direction shown by the arrow “C2” and the second drive lever62is going to turn around the cylindrical part621in a direction shown by the arrow “D2”. As a result, the ice detecting lever60is going to turn and go down as shown by the arrow “F2” inFIGS. 3(A) and 3(B).

In this case, when ice pieces are insufficient, or in a shortage state in the ice storage part1a, moving of the ice detecting lever60downward is permitted and thus the second drive lever62is capable of turning in the direction shown by the arrow “D2” to cause the protruded part625to press the end part755aof the cutout part755and thus the driven ring751is turned in the direction shown by the arrow “D2”. Accordingly, when a timing at which the first protruded part753cof the pressing lever753starts to abut with the slant face752aof the protruded part752of the driven ring751is set to be a boundary position between a shortage state and a full state of ice pieces in the ice storage part1a, ice quantity in the ice storage part1acan be detected on the basis of an “ON” or “OFF” operation by using the ice detecting switch71.

In this embodiment, the driven ring751is moved with a play with respect to the second drive lever62. Therefore, even when the second drive lever62starts to turn in a reverse direction shown by the arrow “D2” after the second drive lever62has been turned in the direction shown by the arrow “D1”, the protruded part625moves only in the inside of the cutout part755and thus the driven ring751is not moved. However, since the leaf contact piece711applies an urging force, which is going to cause the leaf contact piece711to return from its elastically deformed state, to the pressing lever753, when the second drive lever62is turned in the direction shown by the arrow “D2”, the pressing lever753presses the slant face752aformed in the protruded part752of the driven ring751to move the driven ring751in the direction shown by the arrow “D2”. Therefore, the driven ring751is moved before the driven ring751is driven by the second drive lever62. Accordingly, the leaf contact piece711can be quickly returned from the elastically deformed state even before the driven ring751is driven by the second drive lever62. As a result, in the ice detecting switch71, the leaf contact piece711quickly returns to a state where the leaf contact piece711contacts with the end part713aof the leaf contact piece713. Therefore, even when an operation is transmitted to the ice detecting switch71through the cam mechanism, an unstable region is not occurred in the ice detecting switch71where a state that the leaf contact pieces711,712,713are contacted is not clearly different from a state that they are separated. Accordingly, an electric obstacle does not occur.

When ice pieces are in a full state in the ice storage part1a, moving of the ice detecting lever60downward is prevented by the ice pieces. Therefore, turning of the second drive lever62in the direction shown by the arrow “D2” is prevented and thus the leaf contact piece711maintains to have contacted with the leaf contact piece712. After the ice detecting lever60is prevented from moving down by the ice pieces, the first drive lever61is prevented from turning in the direction shown by the arrow “C2”. Therefore, the pawl part611of the first drive lever61does not follow the cam part552of the rotary cam body55in the “C2” direction and thus the ice detecting lever60does not go down from a position restricted by the ice pieces even when the rotary cam body55is turned.

FIG. 8(B)is an explanatory perspective view showing three leaf contact pieces which structure the main switch72for the ice making device. In this embodiment, the main switch72is structured by utilizing the second space47formed between the base plate42and the outer case43shown inFIG. 3(A). In order to structure the main switch72, an upper half portion of the rotary cam body55is utilized which protrudes from the first space46to the second space47through the through hole421of the base plate42. In other words, the rotary cam body55includes a large diameter part553formed in a cylindrical shape, a middle diameter part554having a smaller diameter than the large diameter part553, a first cam part558having a smaller diameter than the middle diameter part554, a second cam part559having a smaller diameter than the first cam part558, and a small diameter part555having a smaller diameter than the second cam part559, which are formed upward in this order to be in a multistage shape from the outer teeth gear54. This multistage portion is disposed in the second space47. Both of side faces of the first cam part558and the second cam part559are formed to be cam faces provided with stepped parts558band559bwhose diameters are sharply varied in their circumferential direction. The diameters of these cam faces increase in a direction shown by the arrow “B” from the stepped parts558band559b. Further, positions of the stepped parts558band559bof the first cam part558and the second cam part559are shifted from each other in a circumferential direction and the stepped part559bis located backward to the stepped part558bin the direction shown by the arrow “B”. In this embodiment, the middle diameter part554is formed with a protruded part556for operating a leaf contact piece of a water-supply switch73described below.

As shown inFIGS. 8(A) and 8(B), three leaf contact pieces721,722and723which structure the main switch72(leaf switch) for the ice making device are disposed on the base plate42so as to extend toward the rotary cam body55. The leaf contact piece723is disposed at a position nearest to a center axial line of the rotary cam body55, the leaf contact piece722is disposed on its outer side, and the leaf contact piece721is disposed on its further outer side. A tip end part723cof the leaf contact piece723is elastically abutted with a side face of the second cam part559. Further, in an initial state, a tip end part722cof the leaf contact piece722is dropped in a low portion of the stepped part558bto elastically contact with the leaf contact piece723. On the other hand, a tip end part721cof the leaf contact piece721is elastically abutted with a side face of the first cam part558.

The leaf contact piece723is straightly and horizontally extended from its base end side and then perpendicularly turned upward, i.e., its extending direction is bent and, after that, the leaf contact piece723is extended horizontally again. A lower edge of the tip end part723cslides on an upper face of the first cam part558.

The leaf contact pieces721and222are formed in a shape such that their base end portions are straightly extended at the same height position as that of the base end portion of the leaf contact piece723and the widths of the tip end parts721cand722care enlarged in an upward direction. Upper edge portions of the tip end parts721cand722care set at the same height position as that of the upper edge portion of the tip end part723cof the leaf contact piece723. Further, a front edge of the leaf contact piece721is slightly extended and protruded to a front end side from a front edge of the leaf contact piece722. When the rotary cam body55is turned in the direction as shown by the arrow “B”, the tip end parts721cand722cof the leaf contact pieces721and222structured as described above move along the side face of the first cam part558and the underside edges of the tip end parts721cand722cslide on the upper face of the middle diameter part554.

In an initial state, i.e., the home position of the main switch72structured as described above, the leaf contact piece723is located at a higher portion of the stepped part559band the leaf contact piece722is located at a lower portion of the stepped part558band thus the leaf contact piece722contacts with the leaf contact piece723. When the rotary cam body55is turned in the direction shown by the arrow “B” from this state, the tip end part723cof the leaf contact piece723drops on a lower portion of the stepped part559band thus the leaf contact piece722is separated from the leaf contact piece723. Further, immediately before the tip end part723cof the leaf contact piece723drops on the lower portion of the stepped part559b, the tip end part721cof the leaf contact piece721drops on a lower portion of the stepped part558band thus the leaf contact piece721is connected to the leaf contact piece722. When the rotary cam body55is further turned in the direction as shown by the arrow “B”, the leaf contact pieces721,722and723will be shifted to a state that they are located at higher portions of the stepped parts559band558band then return to the initial state.

In this embodiment, a water supply switch73shown inFIG. 10(leaf switch) is structured by utilizing a second space47between the base plate42and the outer case43shown inFIG. 3(A). Similarly to the main switch72, the water supply switch73is also structured by utilizing the upper half portion of the rotary cam body55which protrudes into the second space47from the first space46through the through hole421of the base plate42. In other words, a projection556is formed on a side face of the middle diameter part554and, on the other hand, two leaf contact pieces731and732are extended toward the middle diameter part554of the rotary cam body55.

In the water supply switch73structured as described above, the leaf contact piece731is separated from the leaf contact piece732in the initial state, which is in an “OFF” state. From this state, when the rotary cam body55is turned in the direction shown by the arrow B and the leaf contact piece731is pressed by the projection556toward the leaf contact piece732, the leaf contact piece731and the leaf contact piece732come into contact with each other to be in an “ON” state. When the rotary cam body55is further turned in the direction shown by the arrow “B” and the leaf contact piece731returns to its original position, the leaf contact piece731is separated from the leaf contact piece732to return to an “OFF” state.

In this embodiment, a water supply amount adjust mechanism79for adjusting “ON”/“OFF” timing with the water supply switch73is structured on the base plate42. The water supply amount adjust mechanism79is provided with an arch-shaped input lever790(operation member) for adjusting a position of the leaf contact piece732. The input lever790includes a cylindrical part791into which a support shaft protruding from the base plate42is fitted, a pawl part792abutting with the tip end part of the leaf contact piece732at its tip end side, and an operation part793protruding outside of the case body4on an opposite side to the pawl part792with respect to the cylindrical part791. When the operation part793is moved along an edge of the base plate42, as shown by the arrows “G1” and “G2”, the input lever790is turned around the cylindrical part791to change the position of the pawl part792. Therefore, when the input lever790is turned in the direction shown by the arrow “G1”, the tip end side of the leaf contact piece732is resiliently bent in a direction which is separated from the leaf contact piece731and thus a timing when the water supply switch73is changed from an “OFF” state to an “ON” state becomes late and a timing changed from the “ON” state to the “OFF” state becomes early. Accordingly, a water supply time period from the water-supply part22to the ice tray21which is described with reference toFIG. 1is shortened and thus an amount of water supply to the ice tray21is decreased to be capable of making smaller ice pieces. On the other hand, when the input lever790is turned in a direction shown by the arrow “G2”, the tip end side of the leaf contact piece732is resiliently bent in a direction coming close to the leaf contact piece731and thus a timing when the water supply switch73is changed from an “OFF” state to an “ON” state becomes early and a timing changed from the “ON” state to the “OFF” state becomes late. As a result, a water supply time period from the water-supply part22to the ice tray21becomes longer and thus an amount of water supply to the ice tray21is increased to be capable of making larger ice pieces.

An end portion of the input lever790near the operation part793is fitted into a “U”-shaped groove795aof the support plate795. The support plate795is structured so as to slide along an edge portion of the base plate42. Further, the support plate795is formed with a protruded part795bon its inner side face and, on the other hand, a plate part420which is formed along the edge portion of the base plate42is formed with a plurality of grooves420awhich is capable of engaging with the protruded part795b. A click mechanism79ais structured by the protruded part795band the grooves420a. Therefore, when the input lever790is operated, the support plate795slides along the edge portion of the base plate42and the protruded part795bof the support plate795is moved over a portion between the grooves420aof the plate part420and thus a click feeling can be obtained. In addition, the input lever790is held at a prescribed position by the protruded part795bengaging with the groove420a.

According to the water supply amount adjust mechanism79as described above, a spaced distance between the leaf contact pieces731and732can be adjusted only by deforming the tip end side of the leaf contact piece732to change its position and thus timings when the water-supply switch73is turned “ON” or “OFF” can be adjusted. Therefore, when an amount of water (size of an ice piece) supplied to the ice tray21is to be adjusted, the amount of water can be easily adjusted from the outside, which is different from a case that a micro switch is used for the water-supply switch73. In addition, since both the water-supply switch73and the water supply amount adjust mechanism79are mounted on the base plate42, assembling is easily performed with a high degree of positional accuracy. Further, as described below, both the leaf contact pieces731and732are held with the contact piece holding part48which is structured on the base plate42and thus assembling is easily performed.

In accordance with an embodiment, both of the leaf contact pieces731and732may be deformed as the water supply amount adjust mechanism79and, alternatively, the leaf contact piece731which is driven by the rotary cam body55may be deformed as the water supply amount adjust mechanism79. However, in this embodiment, the leaf contact piece732which is not moved by the rotary cam body55is deformed by the input lever790. Therefore, a timing of the leaf contact piece731which is driven by the rotary cam body55is not varied and thus the water-supply switch73is surely operated.

Next, an operation of the drive unit will be briefly described below with reference toFIGS. 11(A) through 11(F)while related to a total operation described with reference toFIG. 3(A)throughFIG. 5(D).FIGS. 11(A) through 11(F)are explanatory views showing operations of the drive unit.

In the initial state, positions of the rotary cam body55, the first drive lever61, the second drive lever62, the pressing lever753, the leaf contact piece723, and the leaf contact piece731are set as shown inFIG. 11(A). In this state, a position of the ice detecting lever60is located at the lowest position. Further, the raking parts232of the raking member23are located at an angle of about 20° with respect to a horizontal direction.

At the time point of “T0” shown inFIG. 6, i.e., in the initial home position, when the thermostat91becomes to an “ON” state, energization to the motor5and the heater26is started and the rotary cam body55is turned. As a result, the raking member23starts to turn in the direction shown by the arrow “A” inFIG. 11(A).

Next, at the time point of “T1” shown inFIG. 6, as shown inFIG. 11(B), the leaf contact piece721is dropped from the step558bimmediately after the raking parts232have been located at an angle of about 10° with respect to the horizontal direction and thus the main switch72is changed to the second state from the first state.

Next, at the time point of “T2” shown inFIG. 6, the turning of the rotary cam body55is transmitted to the ice detecting lever60through the first drive lever61and the second drive lever62and, as shown by the arrow “F1” inFIG. 11(C), the ice detecting lever60goes up.

Next, at the time period of “T3” shown inFIG. 6, the turning of the rotary cam body55is transmitted to the ice detecting lever60through the first drive lever61and the second drive lever62and, when the ice storage part1ais in a shortage state of ice pieces, the ice detecting lever60goes down as shown by the arrow “F2” inFIG. 11(D).

Next, at the time point of “T5” shown inFIG. 6, in other words, at a final stage of one turning of the rotary cam body55, the turning of the rotary cam body55is transmitted to the leaf contact piece731and water is supplied to the ice tray21during the time periods shown inFIGS. 11(E) and 11(F). Then, the rotary cam body55, the first drive lever61, the second drive lever62, the pressing lever753, the leaf contact piece723, the leaf contact piece731and the like return to their original positions.

As described above, in accordance with an embodiment of the present invention, ice pieces are raked out from the ice tray21by the raking parts232of the raking member23while the rotary cam body55is rotated by one turning. In addition, the projection556which serves as a cam face for water supply is formed on the rotary cam body55for operating the water-supply switch at a position just before the rotary cam body55has returned to the initial state shown inFIG. 11(A), in other words, at a final position where the rotary cam body55has been rotated by one turning. Therefore, a timing for supplying water to the ice tray21can be easily realized when the raking parts23have passed the water-supply port and reached to an opposite side to the water-supply port221with respect to the rotation shaft231. However, the projection556may be formed at an end position instead of forming at a final position so that the raking parts are located on an opposite side to the water-supply port with respect to the rotation shaft.

FIG. 12is an explanatory view showing the outer case used in the ice making device in accordance with an embodiment which is viewed from an outer side. In this embodiment, the ice detecting switch71, the main switch72and the water-supply switch73is structured by using a strip-shaped leaf contact pieces711,712,721,722,723,731and732which are formed of a metal plate that is worked in a predetermined shape. The base end sides of the leaf contact pieces are formed, as shown by the leaf contact pieces721,722and723inFIG. 8(B), in a strip shape such that their facing sides to each other are parallel to each other in a widthwise direction and their width dimensions of the base end sides of the leaf contact pieces are equal to each other. Therefore, in this embodiment, all of the leaf contact pieces711,712,721,722,723,731and732are held by utilizing the contact piece holding part48which is formed like a platform on the base plate42in a “V”-shape in plan view. More specifically, a plurality of holding grooves48ais formed in the contact piece holding part48so as to have the same depth and the same shape and the base end sides of the leaf contact pieces711,712,721,722,723,731and732are fitted into and fixed to the holding grooves48a. In this embodiment, since all the depths of the plurality of holding grooves48aare the same, the leaf contact pieces711,712,721,722,723,731and732are held on the base plate42at the same height positions.

In accordance with an embodiment, the tip end parts721cand722cof the leaf contact pieces721and722and the tip end part723cof the leaf contact piece723are abutted with the side faces, of the cam parts558and559of the rotary cam body55whose height positions from the base plate42are different from each other. Therefore, in this embodiment, as described with reference toFIG. 8(B), the leaf contact piece723is straightly and horizontally extended from its base end side and then its extending direction is perpendicularly bent upward and, after that, the leaf contact piece723is extended horizontally again. On the other hand, the leaf contact pieces721and222are formed in a shape such that their base end portions are straightly extended at the same height position as that of the base end portion of the leaf contact piece723and the widths of the tip end parts721cand722care enlarged upward. Therefore, even when the base end sides of the leaf contact pieces721,722and723are held at the same height positions on the base plate42, the tip end parts721c,722cand723cof the leaf contact pieces721,722and723can be preferably abutted with the side faces of the cam parts558and559of the rotary cam body55whose height positions from the base plate42are different from each other.

Further, in this embodiment, a circuit board70which is disposed to face the base plate42is superposed on the base end sides of the leaf contact pieces711,712,721,722,723,731and732. The circuit board70is a PWB (Printed Wiring Board) provided with lands to which terminal parts711e,712e,721e,722e,723e,731eand732eformed upright on the base end sides of the leaf contact pieces711,712,721,722,723,731and732are soldered. The circuit board70is provided with a high rigidity. In addition, the base plate42is covered by the outer case43shown inFIG. 12. The inner bottom face of the outer case43is formed with a rib432corresponding to an outer shape of the contact piece holding part48. Therefore, in a state that the inner case41, the base plate42and the outer case43are superposed to structure the case body4, the base end sides of the leaf contact pieces711,712,721,722,723,731and732are pressed in the widthwise direction, i.e., toward the base plate42by the circuit board70.

In this embodiment as described above, when the leaf contact pieces711,712,721,722,723,731and732are to be mounted on the base plate42, the base end sides of the leaf contact pieces711,712,721,722,723,731and732are fitted into the holding grooves48a. As a result, the leaf contact pieces711,712,721,722,723,731and732are mounted on the base plate42with a high degree of positional accuracy so as to set in a prescribed direction at a predetermined height position and thus a superior workability can be obtained. Further, it is not required to perform positional adjustment after the leaf contact pieces711,712,721,722,723,731and732have been mounted on the base plate42.

Further, the leaf contact pieces711,712,721,722,723,731and732are pressed by the rib432of the outer case43through the circuit board70. Therefore, positional displacement of the leaf contact piece from its initial position or disengagement of the leaf contact piece from the holding groove48adoes not occur. Further, the circuit board70is provided with a high rigidity, which is different from a case that a flexible circuit board is used. Therefore, the leaf contact pieces711,712,721,722,723,731and732are surely fixed by the circuit board70.

In addition, the circuit board70is a single-side circuit board and thus wiring patterns are not formed on its under face. Therefore, insulation to the leaf contact pieces711,712,721,722,723,731and732can be surely secured.

In addition, in a case that the leaf contact pieces711,712,721,722,723,731and732are directly pressed by the outer case43, a metal outer case43cannot be used and, moreover, the outer case43is required to have a high degree of rigidity and a high degree of resistance against electricity. Therefore, material of the outer case43is restricted. However, according to the embodiment of the present invention, the leaf contact pieces711,712,721,722,723,731and732are pressed through the circuit board70and thus restriction in material of the outer case43can be prevented.

In the ice making device1in accordance with the embodiment, cooling for making ice pieces in the ice tray21and heating for raking the ice pieces are performed. The cooling and heating cause the inside of the case body4to occur a rapid temperature change, which may cause dew formation. Further, in a refrigerator or a freezer which is provided with the ice making device1, when a door is opened and closed, a temperature change occurs to cause dew formation. Therefore, in the ice making device1in accordance with an embodiment, a following dew formation countermeasure is adopted.

In other words, in the ice making device1in accordance with the embodiment, as shown inFIG. 3(A), the motor5, the transmission mechanism50, the lever drive mechanism65, the thermostat91and the like are disposed in the first space46which is structured with the inner case41and the base plate42. On the other hand, the upper half portion of the rotary cam body55(cam face for the leaf switches), the ice detecting switch71, the main switch72, the water-supply switch73, the circuit board70and the like are disposed in the second space47which is structured with the outer case43and the base plate42. Further, the base plate42is formed with the through hole421. However, the large diameter part553formed in a cylindrical shape of the rotary cam body55is fitted to the through hole421and thus a space formed with the through hole421is substantially closed. The base plate42is formed with slits425but flat plate-shaped terminals5b(power supply member) which are extended toward the outer case43from the upper face of the motor5are fitted in the slits425. Therefore, the first space46and the second space47are substantially separated form each other by the base plate42. Accordingly, even when the ice tray21(ice making unit2) is abutted with a side face of the first space46(side face of the inner case41), a rapid temperature variation is not occurred in the second space47and thus dew formation does not occur.

A bottom plate part of the outer case43shown inFIG. 12is formed with a rib431(second partition wall) whose height is slightly lower than that of the outer wall435. Therefore, when the base plate42and the outer case43are superposed on each other, the inside of the second space47is further partitioned into two spaces (first inner side small space471and second outer side small space472) and the first inner side small space471is separated from a surrounding portion by the rib431and the outer wall435. Further, the rib431includes a facing portion431awhich faces the outer wall435of the outer case43to doubly surround the first inner side small space471.

In accordance with this embodiment, the upper half portion of the rotary cam body55, the ice detecting switch71, the main switch72, the water-supply switch73, the circuit board70and the like are disposed in the first inner side small space471and, on the contrary, the input lever790whose operation part793is required to be extended outside and the like are disposed in the second outer side small space472. In addition, when the ice tray21is abutted with the side face of the inner case41, the ice tray21is located at a position corresponding to the side of the second outer side small space472and the first inner side small space471is located at a position corresponding to a portion apart from the ice tray21(heater26) than the second outer side small space472. Accordingly, dew formation in the first inner side small space471in the inside of the second space47, where the ice detecting switch71, the main switch72, the water-supply switch73, the circuit board70and the like are disposed, can be surely prevented.

In accordance with the embodiment as described above, above-mentioned double dew formation countermeasures are provided in the first inner small space471where the ice detecting switch71, the main switch72, the water-supply switch73and the circuit board70are disposed. Therefore, even when variation of temperature occurs outside, dew is not formed in the first inner side small space471and thus malfunction due to freezing does not occur even when an inexpensive leaf switch is used for the ice detecting switch71, the main switch72and the water-supply switch73.

A water supply amount adjust mechanism for adjusting “ON” and “OFF” timing of the water supply switch73may be structured as described below with reference toFIG. 13(A)throughFIG. 16(C). A basic structure of this embodiment is similar to the ice making device which is described with reference toFIG. 1throughFIG. 12. Therefore, the same notational symbols are used in common portions and their descriptions are omitted.

FIG. 13(A)is an explanatory view showing an ice making device in accordance with another embodiment of the present invention which is viewed from a case body side.FIG. 13(B)is an explanatory view showing the ice making device in which an outer case is detached.FIG. 14(A)is an explanatory view showing a water supply amount adjust mechanism which is structured in the ice making device shown inFIG. 13(B)in a state that an external operation is not performed, andFIG. 14(B)is an explanatory view showing the water supply amount adjust mechanism when an external operation is performed.FIG. 15(A)is an explanatory perspective view showing a support structure of a pinion member of an operation member which is used in the water supply amount adjust mechanism structured in the ice making device shown inFIG. 13(B), andFIG. 15(B)is a perspective view showing the pinion member which is viewed from an obliquely lower side.FIG. 16(A)is a plan view showing a pinion member of an operation member used in a water supply amount adjust mechanism in accordance with the embodiment of the present invention,FIG. 16(B)is its side view andFIG. 16(C)is its cross-sectional view.

As shown inFIGS. 13(A),13(B),14(A) and15(A), in an ice making device in this embodiment, a water supply amount adjust mechanism79for adjusting “ON” and “OFF” timing of the water supply switch73is structured in the inside of the case body4by utilizing a space between the outer case43and the base plate42. In the water supply amount adjust mechanism79in this embodiment, an operation member78for adjusting a position of the leaf contact piece732includes a pinion member76, which is rotatably supported by a support shaft426stood up from the base plate42, and a lever-shaped transmitting member77which is provided with a rack-shaped teeth part770engaging with outer teeth760of the pinion member76. The transmitting member77transmits an external operation applied to the pinion member76to the leaf contact piece732.

The water supply switch73and the operation member78(pinion member76and transmitting member77) are disposed in the case body4. The outer case43is formed with a circular aperture430at a position overlapping with an upper end face765of a head part764of the pinion member76. Therefore, the upper end face765of the head part764of the pinion member76is exposed outside through the circular aperture430. A groove766is formed on the upper end face765of the head part764. The transmitting member77is provided with a cylindrical part791into which a support shaft protruded from the base plate42is fitted and a pawl part792abutting with the tip end part of the leaf contact piece732.

Therefore, in the water supply amount adjust mechanism79, when a minus screwdriver (not shown) or the like is inserted from outside of the outer case43into the groove766formed on the head part764of the pinion member76and turned, the pinion member76is also turned. As a result, the transmitting member77is, as shown by the arrows “G1” or “G2”, turned around the cylindrical part791to cause a position of the pawl part792to change. Therefore, when the transmitting member77is turned in a direction as shown by the arrow “G1”, the tip end side of the leaf contact piece732is resiliently bent in a direction which is separated from the leaf contact piece731and thus a timing when the water supply switch73is changed to “ON” from “OFF” becomes late and a timing changed from “ON” to “OFF” becomes early. Accordingly, a water supply time period from the water-supply part22to the ice tray21which is described with reference toFIG. 1is shortened and thus an amount of water supply to the ice tray21is decreased to make smaller ice pieces. On the other hand, when the transmitting member77is turned in a direction shown by the arrow “G2”, the tip end side of the leaf contact piece732is resiliently bent in a direction coming close to the leaf contact piece731and thus a timing when the water supply switch73is changed to “ON” from “OFF” becomes early and a timing changed from “ON” to “OFF” becomes late. As a result, a water supply time period from the water-supply part22to the ice tray21becomes longer and thus an amount of water supply to the ice tray21is increased to make larger ice pieces.

In order to structure the water supply amount adjust mechanism79as described above, the base plate42is formed with a ring-shaped projection427circumferentially formed around the support shaft426and a circular arc-shaped projection428between the support shaft426and the ring-shaped annular projection427. The ring-shaped projection427and the circular arc-shaped projection428are concentrically formed with the support shaft426. The circular arc-shaped projection428is formed in an angular range of about 90 degrees around the support shaft426.

As shown inFIGS. 14(A) through 16(C), the pinion member76includes a circular plate part761having a large diameter, a middle diameter part762having a smaller diameter than the circular plate part761, a small diameter part763having a smaller diameter than the middle diameter part762, and the head part764having smaller diameter than the small diameter part763in this order upward from a lower end side. The pinion member76is formed with a bottomed shaft hole76ainto which the support shaft426of the base plate42is fitted and which is extended in an axial line direction “L”. Outer teeth760are formed on an outer peripheral face of the middle diameter part762. A plurality of triangular teeth767is formed on an upper face of the small diameter part763so as to extend in a radial direction as an engagement portion for structuring a lock mechanism78adescribed below.

The circular plate part761is formed with two circular arc-shaped opening parts761aacross the shaft hole76aso that arm parts761bare formed left. The arc-shaped opening part761ais penetrated through the circular plate part761. Therefore, the middle diameter part762, the small diameter part763and the head part764of the pinion member76, which are located on an inner side of the circular arc-shaped opening parts761a, are structured as a movable part76cwhich is capable of being displaced to one side “L1” in the axial line direction “L” with respect to a circular ring frame portion76dwhich is located on an outer side of the circular arc-shaped opening parts761aof the circular plate part761when the head part764is pressed to the one side “L1” in the axial line direction “L”.

A lower end face of the circular ring frame portion76dof the circular plate part761is formed with two support projection769across the shaft holes76a. A circular arc-shaped projection768is formed on an inner side of the circular arc-shaped opening parts761ain an angular range of about 90° around the shaft hole76a. The support projections769are formed at an angular position of 90° shifted in a circumferential direction from the arm parts761b.

A cylindrical part436protruding toward the pinion member76is formed at a portion of the circular aperture430of the outer case43. A plurality of triangular teeth437extending in a radial direction is formed on an end face of the cylindrical part436as an engagement portion for structuring a lock mechanism78adescribed below. A pitch of the teeth437in the circumferential direction is equal to that of the triangular teeth767which are formed on the pinion member76. Therefore, as shown inFIG. 14(a), the triangular teeth437of the outer case43and the triangular teeth767of the pinion member76are engaged with each other to structure a lock mechanism78afor preventing the pinion member76from turning. In accordance with an embodiment, the pinion member76is assembled under a state that the movable part76C has been resiliently bent. Therefore, a return force is generated in the “L2” direction and thus the lock mechanism is structured such that the pinion member76is surely engaged with the engagement portion of the outer case43. As described above, in accordance with an embodiment of the present invention, the pinion member76is disposed between the base plate42and the outer case43in a state that the movable part76cis displaced on the downward side and the movable part76cis urged upward by the shape return force of the pinion member76. Therefore, the upper face of the small diameter part763of the pinion member76on which the teeth767are formed is urged to the end face of the cylindrical part436of the outer case43on which the teeth437are formed. Accordingly, even when vibration or the like is applied, unless the head part764is pressed by an external force, the teeth437of the outer case43and the teeth767of the pinion member76are maintained to be engaged with each other and thus the turning of the pinion member76is prevented.

In order to assemble the water supply amount adjust mechanism79by utilizing the operation member78which is structured as described above, the transmitting member77is mounted on the base plate42and the support shaft426of the base plate42is fitted into the shaft hole76aof the pinion member76. As a result, the outer teeth760of the pinion member76and the teeth part770of the transmitting member77are engaged with each other. The support projections769of the pinion member76are abutted with the upper face of the ring-shaped projection427of the base plate42and the circular arc-shaped projection768of the pinion member76is disposed at a position shifted from the circular arc-shaped projection428of the base plate42. In this state, when the outer case43is attached so as to cover the base plate42, the end face of the cylindrical part436of the outer case43presses the upper face of the small diameter part763of the pinion member76. As a result, the pinion member76is disposed between the base plate42and the outer case43in a state that the movable part76cis displaced downward. Therefore, the upper face of the small diameter part763of the pinion member76on which the teeth767are formed is urged to the end face of the cylindrical part436of the outer case43on which the teeth437is formed by the shape return force of the pinion member76. Accordingly, the triangular teeth437of the outer case43and the triangular teeth767of the pinion member76are engaged with each other and the lock mechanism78aprevents the pinion member76from turning.

In order to adjust amount of water supply in this state, a minus screwdriver is inserted to the groove766of the pinion member76from outside of the outer case43and presses the head part764of the pinion member76. As a result, as shown inFIG. 14(B), the pinion member76is displaced to the one side “L1” in the axial line direction “L” and the lock mechanism78ais disengaged. In other words, when the head part764of the pinion member76is pressed, the arm parts761dare resiliently bent to displace the movable part76cto the one side “L1” in the axial line direction “L”. Therefore, in the lock mechanism78a, engagement of the triangular teeth437of the outer case43with the triangular teeth767of the pinion member76is released. In this state, since turning of the pinion member76is permitted, the pinion member76is turned by a minus screwdriver and turning of the pinion member76is transmitted to the leaf contact piece732through the transmitting member77. In this case, turning range of the pinion member76is limited to 90° because the circular arc-shaped projection768of the pinion member76is abutted with the circular arc-shaped projection428of the base plate42. Therefore, the leaf contact piece732is not excessively deformed.

After amount of water supply has been adjusted as described above, the minus screwdriver is disengaged. As a result, the movable part76cof the pinion member76is displaced to the other side “L2” in the axial line direction “L” by shape return forces of the arm parts761d. Therefore, the triangular teeth437of the outer case43and the triangular teeth767of the pinion member76are engaged with each other and turning of the pinion member76is prevented.

According to the water supply amount adjust mechanism79as described above, a spaced distance between the leaf contact pieces731and732can be adjusted only by deforming the tip end side of the leaf contact piece732to change its position and thus timings when the water-supply switch73is turned “ON” or “OFF” can be adjusted. Therefore, amount of water (size of an ice piece) supplied to the ice tray21can be easily adjusted from the outside.

Further, the water supply switch73and the entire operation member78are accommodated within the inside of the case body4and the operation member78is not protruded outside from the case body4. Therefore, the size of the ice making device1can be reduced.

Further, the lock mechanism78ais structured to prevent the operation member78from displacing during a period except when an external operation is performed. Therefore, the operation member78is not mistakenly operated. In addition, in order to structure the lock mechanism78a, a part of the pinion member76is structured as the movable part76cwhich is capable of being displaced. Therefore, the lock mechanism78ais structured with a reduced number of parts.

In accordance with an embodiment of the present invention, the lock mechanism78ato the operation member78may be structured such that the entire pinion member76is moved in the axial line direction “L” to prevent the operation member78from turning and to permit the operation member78to turn. Further, the lock mechanism78ato the operation member78may be structured such that displacement of the transmitting member77is permitted and prevented.