Ice Dispenser

1. Field of the Invention

The present invention relates generally to an ice dispensing apparatus equipped with an ice making mechanism and an ice storage box, and more particularly to the discharge of ice pieces from the ice storage box to which the ice pieces are supplied from the ice making mechanism.

2. Description of the Prior Art

There are various known types of ice dispensers. Most of the ice making mechanisms incorporated in such ice dispensers are of a so-called auger type in which an evaporator pipe is wound around an outer peripheral surface of a cylinder supplied with water for making ice, wherein an ice layer is produced on and along the inner surface of the cylinder under a cooling action produced by coolant flowing through the evaporator pipe. The ice layer thus formed is scraped off into ice shavings by means of a helical blade mounted around a rotatable shaft disposed within the cylinder, the resulting ice shavings being then fed upwardly to pass forcibly through a pressure head having a plurality of compression channels to be converted into ice columns which are then broken into small ice pellets or pieces having a desired length. The ice pieces thus produced are stored within an ice storage chamber or box disposed above the cylinder. The rotatable shaft mentioned above has a lower end portion operatively coupled to a drive motor and extends upwardly through the cylinder and the pressure head into the ice storage box, wherein the upper end portion of the rotatable shaft is coupled to an agitator assembly. An ice storage level sensing or detecting switch is installed within the ice storage box. When the ice storage box becomes full of ice pieces, this state is detected by the ice storage level switch, whereby a compressor constituting a part of the ice making mechanism and the drive motor for rotating the rotatable shaft are stopped.

In such an ice dispenser apparatus, when the ice pieces stored within the ice storage box are to be discharged, the drive motor is energized to rotate the agitator assembly and a discharge port shutter is actuated to open a discharge a port provided in a side wall portion of the ice storage box. Thus, an amount of small ice pieces is dispensed through the discharge port, which amount can be determined by the time period during which the discharge port shutter is maintained open.

The known ice dispenser apparatus is, however, disadvantageous in that since the amount of ice dispensed for a predetermined time through the discharge port having a fixed cross-sectional area may vary dependending on variable parameters such as quality of ice, shape of ice pieces and others, the amount of ice being dispensed differs significantly from one discharging another even when the period during which the discharge port shutter is opened is maintained constant. Furthermore, since unevenness or dispersion in the amount of ice as dispensed becomes more significant as the shutter release duration is increased, the uniform ice dispensing capability of the apparatus becomes even further degraded when the amount of ice dispensed at a time is increased.

Accordingly, it is a primary object of the present invention to provide an ice dispenser apparatus which is capable of suppressing the unevenness or dispersion in the dispensed amount of ice to a possible minimum.

In view of the above and other objects which will be more apparent as the following description proceeds, there is provided, according to an aspect of the present invention, an ice dispenser apparatus including an ice making mechanism and an ice storage box for storing ice pieces produced by the ice making mechanism, wherein when the ice pieces are discharged from the ice storage box, a discharge port shutter normally closing a discharge port provided in the ice storage box at a lower portion thereof is opened by a discharge port shutter actuating device. The apparatus further comprises a transient storage chamber (also referred to as the metering chamber) communicating with the discharge port and having a normally closed aperture for transiently storing a predetermined amount of ice pieces discharged from the ice storage box through the discharge port when the discharge port shutter is opened, and a transient storage chamber shutter provided in association with the transient storage chamber and adapted to be actuated by a transient storage chamber shutter actuating device for selectively opening or closing the aperture, wherein the discharge port shutter and the transient storage chamber shutter are opened and closed by the respective actuating devices in such a manner that a predetermined amount of ice pieces is temporarily stored once within the transient storage chamber before being disposed therefrom.

When ice is dispensed, the amount of ice to be dispensed is always determined by the volume of the transient storage (or metering) chamber. Accordingly, inconsistencies in the amount of ice dispensed can be reduced to a minimum even when the amount of ice discharged from the ice storage box varies due to changes in the ice quality and shape. Such unevenness in the amount of ice as dispensed can also be suppressed in an ice dispenser apparatus designed to dispense a large amount of ice by repeating the ice dispensing operation for a desired number of times in an automatic manner.

In the course of the following detailed description, reference will be made to the attached drawings in which the same reference numerals denote the same or similar parts throughout the figures and in which:

FIG. 1 is a vertical sectional view showing schematically an ice dispenser apparatus according to an embodiment of the present invention in a state in which a discharge port shutter and a metering chamber shutter are closed;

FIG. 2 is a vertical sectional view showing the ice dispenser apparatus of FIG. 1 in a state in which both the shutters are opened;

FIG. 3 shows a timing chart for illustrating operations of the discharge port shutter and the metering chamber shutter of the ice dispenser apparatus shown in FIG. 1;

FIGS. 4A and 4B are schematic diagrams showing a wiring arrangement comprising various components of a control unit for controlling operations of the ice dispenser shown in FIG. 1;

FIG. 5 is a timing chart illustrating shutter operations of the discharge port shutter and the metering chamber shutter performed under the control of the control unit shown in FIGS. 4A and 4B;

FIGS. 6A and 6B are schematic diagrams showing a circuit arrangement comprising various components of another control unit which can also be employed for controlling the ice dispenser apparatus shown in FIGS. 1 and 2;

FIG. 7 is a timing chart illustrating operations of the discharge port shutter and the metering chamber shutter performed under the control of the control unit shown in FIGS. 6A and 6B; and

FIG. 8 is a vertical sectional view showing an ice dispenser apparatus according to a modified embodiment of the present invention.

Referring to the drawings and in particular to FIGS. 1 and 2, there is shown an ice dispenser apparatus according to an embodiment of the present invention which is provided with an auger-type ice making mechanism generally denoted by reference numeral 1. The auger-type ice making mechanism 1 itself may be conventional and includes a vertically disposed hollow cylinder 1a, a vaporizing pipe 1b wound around the outer peripheral surface of the cylinder 1a and a rotatable auger 1c extending through the interior of the cylinder 1a. The auger 1c includes a rotatable shaft having a lower end portion coupled to a drive motor 2 and an intermediate enlarged portion which is formed with a helical tooth or blade, as can be seen in FIGS. 1 and 2. On the other hand, the upper end portion of the auger 1c extends upwardly through and beyond a pressure head 4 which is fitted within the cylinder 1a at the upper end portion thereof and which is fixedly secured by appropriate means such as screws 3. Also mounted on the cylinder 1a at the upper end thereof is a hollow ice storage box 5. The ice storage box 5 may preferably have a cylindrical configuration and is comprised of a heat-insulated wall member 5a. As will be seen in the figures, the upper end portion of the auger 1c extends into the interior of the ice storage box 5 and is equipped with a conventional agitator assembly 6 which includes a supporting base member 6a having a substantially cylindrical shape and a plurality of agitating rods 6b extending in various directions.

Extending through a heating insulating shell 8 and the cylinder 1a enclosed therein a water inlet tube 7 is mounted to and open within the cylinder 1a to supply water therein which is to be refrigerated into ice. More specifically, a coolant fed from a compressor (not shown) flows through the vaporizing pipe 1b to cool the cylinder 1a, whereby water within the cylinder 1a is deposited on the inner surface of the cylinder 1a in the form of an ice layer. As the auger 1c is rotated by the drive motor 2, the helical or spiral blade of the auger 1c scrapes the ice layer off of the inner surface of the cylinder. Ice shavings thus produced are fed toward the pressure head 4 and are compressed into ice columns during their passage through the head 4 under the action imparted by well known ice compressing passages 4a provided in the pressure head 4. The upper end portion of each ice column is fed upwardly from the associated compressing portion until it bears forcibly against a shoulder portion 6c of the supporting base member 6a, as the result of which the ice column is broken into ice pieces or pellets having a relatively small size to be subsequently placed on a draining board 5b disposed on the bottom of the ice storage box 5.

Mounted at the top of the ice storage box 5 is a vertically movable disc-type ice storage level detecting switch device 14. When the ice storage box 5 is filled with the ice pieces, this state of the ice storage box 5 is detected by the disc-type switch 14, whereby the drive motor 2 for the compressor (not shown) and the rotatable auger shaft of the ice making mechanism are stopped.

In order that the ice pieces stored within the ice storage box 5 can be discharged outwardly, a discharge or dispensing outlet port 5c having an appropriate size and shape (rectangular in cross section in the illustrated embodiment although it is not shown) is formed in the side wall member 5a of the ice storage box 5. Normally, this discharge port 5c is closed by an associated shutter 9 comprised of a plate member which is mounted on a supporting member 9a by means of pins 9b. The supporting member 9a in turn is pivotally connected to a shutter actuating bar 11a and a shutter locking bar 11b extending outwardly from a shutter open/close mechanism which may be comprised of any known structure. Additionally, the ice storage box 5 is provided with a volume metering device or chamber (which may also be referred to as a transient or temporary storage chamber) 13 having a box-like shape which encloses the peripheral edge portion of the rectangular ice piece discharge port 5c except for the upper edge portion thereof. More specifically, the top portion of the metering chamber 13 is cut out to define an opening or aperture which receives therein the discharging port shutter 9 when the latter is opened, as shown in FIG. 2. Additionally, the metering chamber 13 has a bottom aperture which is usually closed by a metering chamber shutter (which may also be referred to as the dispensing shutter) 10 which is comprised of a sheet member having a substantially L-like profile. The metering chamber shutter 10 is mounted on a supporting member 10a by means of pins 10b, which supporting member 10a in turn is pivotally connected to a shutter actuating bar 12a and a shutter locking bar 12b both extending from a shutter open/close mechanism comprised of a known structure. Parenthetically, the ice dispenser apparatus according to the instant embodiment is shown in a state in which both the discharge port 9 and the metering chamber shutter 10 are closed in FIG. 1, while the apparatus is shown in FIG. 2 in state which both of the shutters are opened.

A possible modification of the ice dispenser described above is shown in FIG. 8. More specifically, although the ice dispenser apparatus shown in FIG. 8 is the same as the one described above in that the metering chamber shutter 10 is comprised of the L-like plate member, the former differs from the latter in that the volume metering chamber 13 is realized by a bent rear wall 13a and a pair of opposite side walls 13b with the front wall being omitted, whereby an aperture is formed on the front side of the volume metering chamber 13 contiguous to the bottom aperture thereof. Due to this modified structure, the L-like metering chamber shutter 10 is designed to close and open not only the bottom aperture of the volume metering chamber 13 but also the front aperture thereof by means of an upstanding leg portion of the L-like sheet shutter member 10. As will be seen in FIG. 8, a wedge-like projection 15 is mounted on the upstanding leg portion of the L-like metering chamber shutter 10 in the vicinity of the upper edge thereof so as to extend into the metering chamber 13.

The modified structure of the ice dispenser apparatus shown in FIG. 8 is advantageous in that not only the bottom aperture but also the front aperture are opened upon opening of the metering chamber shutter 10 ensuring an increased size of the dispensing aperture in total, whereby the undesirable situation of the dispensing channel within the metering chamber 13 becoming partially jammed with ice pieces can be positively prevented. Thus, unevenness or variations in the amounts of ice dispensed can be reduced to a minimum. Furthermore, when the dispensing shutter 10 is opened, the projection 15 shown in FIG. 8 is rotated clockwise to press the ice pieces located within the metering chamber 13 downwardly to thereby assist in smoothly dispensing the ice pieces from the metering chamber (or transient storage chamber) 13.

Next, an ice discharging and dispensing operation of the ice dispenser apparatus described above will be elucidated by referrring to FIG. 3. Unless the ice storage box 5 is fully filled with the ice pieces, the drive motor 2 remains in the energized state to continuously rotate the agitator assembly 6. On the other hand, when the ice storage box 5 is full of ice pieces, the drive motor 2 is in the deenergized state with the agitator assembly 6 stopped. When a request for discharging the ice pieces from the ice storage box 5 occurs at a time point t.sub.1, the drive motor 2 is started if it is at rest at that time period, whereby the agitator assembly 6 starts rotating. Simultaneously, the shutter open/close actuator 11 is activated to open the discharge port shutter 9 to allow a part of the ice pieces within the ice storage box to be discharged into the volume metering chamber 13 by way of the discharge port 5c, as is illustrated in FIG. 3 at (a). After the lapse of time long enough to allow the volume metering chamber 13 to be fully filled with the ice pieces, the metering chamber 10 is opened by the shutter open/close mechanism 12 at a time point t.sub.2 as is shown in FIG. 3 at (b), whereby the predetermined amount or volume of the ice pieces within the metering chamber 13 is dispensed into a cup or the like not shown. Thereafter, the discharge port shutter 9 and the metering chamber shutter 10 are actuated to their respective closed positions by means of the associated shutter open/close mechanisms 11 and 12, respectively, at a time point t.sub.3.

In the case of the illustrated embodiments, the dispensing aperture of the metering or transient storage chamber 13 is provided horizontally at the bottom of the chamber. Accordingly, the ice pieces within the metering chamber 13 can drop immediately therebelow. Thus, the period T.sub.2 during which the metering chamber shutter 10 is opened can be shortened to about 0.2 sec., by way of example. Consequently, even when both the discharge port shutter 9 and the metering chamber shutter 10 are opened, the possibility that the ice pieces be additionally fed outwardly from the discharge port 5c of the ice storage box 5 does not exist, whereby the dispensing of a predetermined amount of ice can be assured with enhanced reliability.

FIGS. 4A and 4B in combination show a circuit diagram of an operation control circuit for controlling operation of the ice dispenser apparatus described above with reference to FIGS. 1 and 2. The operation control circuit includes as major parts thereof high-voltage circuitry 20, low-voltage circuitry 21 and control circuitry 22. The high voltage circuitry 20 is comprised of a discharge port shutter driver SV.sub.1 such as a solenoid actuator serving as the shutter open/close mechanism 11 for selectively opening and closing the discharge port shutter 9, a metering chamber shutter driver SV.sub.2 such as a solenoid-type device serving as the shutter open/close actuator for selectively opening and closing the metering chamber shutter 10, the drive motor 2 mentioned before, the compressor CM also mentioned hereinbefore and a motor fan FM which are interconnected in the manner illustrated. The low-voltage circuitry 21 supplied with electric power from the high-voltage circuitry 20 through a transformer Tr is comprised of a float switch FS, an electromagnetic water valve WV, a fourth relay X.sub.4 and contacts S.sub.1 of the aforementioned ice storage sensor switch 14 which are interconnected in the manner illustrated. Referring in particular to FIG. 4B, the control circuitry 22 connected to the low-voltage circuitry 21 through terminals 22a and 22b includes a first relay X.sub.1, a second relay X.sub.2, a third relay X.sub.3, a first timer TM.sub.1, a second timer TM.sub.2, a third timer TM.sub.3, a fourth timer TM.sub.4 and an ice discharging switch S.sub.2 which are interconnected in a manner as illustrated.

Next, an ice discharging or dispensing operation performed under control of the control circuit mentioned above will be described by also referring to a timing chart illustrated in FIG. 5. At first, a power source switch 20a is closed, whereupon the electromagnetic water valve WV is electrically energized through a normally closed contact X.sub.4-2 of the relay X.sub.4 to allow water to be fed to a water tank (not shown). When the water level within the water tank has attained a preset upper limit, the upper limit contact u of the float switch FS is closed to electrically energize the fourth relay X.sub.4 which is then maintained in a self-holding state through the cooperation of the lower limit contact d of the float switch FS already closed and the normally opened contact X.sub.4-1 of the fourth relay X.sub.4, while the normally closed contact X.sub.4-2 thereof is opened to interrupt the water supply to the water tank. Furhtermore, since the normally opened contact X.sub.4-3 of the fourth relay X.sub.4 is closed, the first relay X.sub.1 is electrically energized, whereby both of the normally opened contacts X.sub.1-1 and X.sub.1-2 are simultaneously closed to energize the drive motor 2 and the compressor CM, whereupon the ice making operation of the ice dispenser apparatus is started. When the amount of water contained within the water tank is lowered, as the ice making operation proceeds, until the lower limit water level is ultimately reached, the lower limit contact d is opened, whereupon the fourth relay X.sub.4 is deenergized to restart the water supply to the water tank. The first relay X.sub.1 is maintained in a self-holding state for a period set by the fourth timer TM.sub.4, which period is at least long enough that the water level in the tank attains the upper limit for closing the upper limit contact u of the float switch FS to thereby energize the fourth relay X.sub.4. Consequently, during this period, the ice making operation is continued. The ice pieces thus produced are stored in the ice storage box 5. When the upper limit contact u of the float switch FS is not closed upon lapse of the time set by the timer TM.sub.4 due to a halt in the water supply from the water service system or the like, the first relay X.sub.1 is released from the self-holding state in response to the opening of the contact TM.sub.4-1 of the fourth timer TM.sub.4, whereupon both the compressor CM and the drive motor 2 are electrically deenergized to thereby cause the ice making operation to be stopped. In this way, the ice dispenser apparatus is safeguarded. On the other hand, when a sufficient amount of the ice pieces has been stored within the ice storage box 5, the contact S.sub.1 of the ice storage level sensor switch 14 incorporated in the high-voltage circuitry 21 is opened, in response to which the ice-making operation and the water supply operation are interrupted.

When the ice pieces are to be dispensed from the storage box 5, a period of time is set by the second timer TM.sub.2 that corresponds to the amount of ice pieces to be discharged, which is followed by actuation of the ice discharging switch S.sub.2. The setting of the second timer TM.sub.2 can be manually performed through any appropriate setting means such as a knob or the like. When the ice discharging switch S.sub.2 is manipulated, the second relay X.sub.2 is electrically energized and set to the self-holding state due to the closing of the normally opened contact X.sub.2-3 of the second relay X.sub.2. The normally opened contacts X.sub.2-1, X.sub.2-2 and X.sub.2-4 of the second relay are also closed. When the contacts X.sub.2-1 and X.sub.2-2 are closed in this manner, the solenoid device SV.sub.1 serving as the discharging port shutter open/close actuator 11 and the drive motor 2 for driving the agitator assembly 6 start respective operations at the time point t.sub.1 shown in FIG. 5 at (a), whereby a portion of the ice pieces contained within the ice storage box 5 is discharged into the transient storage or metering chamber 13. Additionally, the first timer TM.sub.1 is activated in response to the closing of the contact X.sub.2-4. When a time T.sub.1, which is so selected as to allow the metering chamber 13 to be fully filled with the ice pieces discharged from the ice storage box 5, has elapsed at a time point t.sub.2, the contacts TM.sub.1-1, T.sub.1-2 and TM.sub.1-3 of the first timer T.sub.1 are closed. When the contact T.sub.1-1 is closed, the first timer TM.sub.1 is set to the self-holding state, while the second timer TM.sub.2 is activated in response to the closing of the contact TM.sub.1-2 with the third relay X.sub.3 being energized in response to the closing of the contact TM.sub.1-2. When the third relay X.sub.3 is energized, the normally opened contact X.sub.3-1 thereof is closed to energize the solenoid device SV.sub.2 serving as the metering chamber shutter actuating means, whereby the metering chamber shutter 10 is opened to allow the ice pieces to be dispensed from the transient storage or metering chamber 13, as is illustrated in FIG. 5 at (b). When a predetermined time T.sub.2 set by the second timer TM.sub.2 by convenient setting means (not shown) has elapsed at a timer point t.sub.3, the contact TM.sub.2-1 is opened with the contact TM.sub.2-2 being closed. In response to the opening of the contact TM.sub.2-1, the second relay X.sub.2 is released from the self-holding state, whereupon the solenoid device SV.sub.1 and the drive motor 2 are deenergized to stop the operation of the agitator assembly 6 on one hand and to close the discharging port shutter 9 on the other hand. The ice dispensing operation now ends. In this way, the ice pieces can be dispensed from the metering chamber 13 in an amount corresponding to the time or period T.sub.2 spanning the time points t.sub.2 and t.sub.3 during which the discharge port shutter 9 of the ice storage box 5 is maintained in the opened state. Additionally, when the contact TM.sub.2-2 is closed, the third timer T.sub.3 is activated, whereby the contact TM.sub.3-1 is opened at a time point t.sub.4 after the lapse of a short time T.sub.3 beginning from the activation of the third timer TM.sub.3. As a result, the first timer TM.sub.1 is released from the self-holding state to thereby cause the third relay X.sub.3 to be deenergized, whereby the solenoid device SV.sub.2 serving as the metering chamber shutter actuator 12 is deactivated to thereby close the metering chamber shutter 10, as will be seen in FIG. 5 at (b). Due to a short time span or delay between the time points at which the discharge port shutter 9 and the metering chamber shutter 10 are closed, respectively, the ice pieces can be prevented not only from being clamped by the metering chamber shutter member 10 but also from being left within the metering chamber 13.

FIGS. 6A and 6B in combination show another exemplary embodiment of the control circuit which differs from the one shown in FIGS. 4A and 4B in that the normally opened contact X.sub.3-2 of the relay X.sub.3 incorporated in the high-voltage circuitry 20 is connected in series to the drive motor 2 and in that a fifth relay X.sub.5 and a counter CNT as well as the associated contacts are provided in the control circuitry 22.

In the ice dispenser apparatus equipped with the control circuit shown in FIGS. 6A and 6B, the number of times the ice discharging operation is to be performed repeatedly depending on the desired amount of ice to be dispensed is first set in the counter CNT by a convenient setting means such as a knob or the like (not shown).

When the ice discharging switch S.sub.2 is operated after the above-mentioned number of times has been set, the fifth relay X.sub.5 serving to hold the ice discharging operation is energized and set to the self-holding state in response to the closing of the normally opened contact X.sub.5-1 of the fifth relay. The normally opened contact X.sub.5-2 of the fifth relay is closed while the normally closed contact X.sub.5-3 thereof is opened.

When the normally closed contact X.sub.5-3 of the fifth relay X.sub.5 is thus opened, the signal input to the reset terminal of the counter CNT ceases, whereby the counter CNT assumes a state capable of counting the number of times a pulse is applied to the input terminal In. Furthermore, the closing of the normally open contact X.sub.5-2 of the fifth relay is accompanied by energization of the second relay X.sub.2 for enabling the ice discharging operation, whereby the normally open contacts X.sub.2-1, X.sub.2-2 and X.sub.2-3 of the second relay X.sub.2 are closed.

In response to the closing of the contacts X.sub.2-1 and X.sub.2-2, the discharge port shutter(9) driving device SV.sub.1 and the motor 2 for driving the agitator assembly 6 are actuated, respectively, at a time point t.sub.1 shown in FIG. 7 at (a), whereby a portion of the ice pieces is discharged into the metering chamber 13 from the ice storage box 5. Additionally, the first timer TM.sub.1 is activated in response to the closing of the contacts X.sub.2-3. The contact TM.sub.1-1, TM.sub.1-2 and TM.sub.1-3 of the first timer TM.sub.1 are closed at a time point t.sub.2 after the lapse of a period T.sub.1 which is set long enough for the metering chamber 13 to become filled with the ice pieces.

When the contact TM.sub.1-1 of the first timer is closed, the first timer TM.sub.1 is set to the self-holding state, while the second timer TM.sub.2 is triggered when the contact TM.sub.1-2 is closed with the third relay X.sub.3 being energized in response to the closing of the contact TM.sub.1-3 of the first timer.

When the third relay X.sub.3 is energized, the normally opened contact X.sub.3-1 thereof is closed to activate the metering chamber shutter actuator solenoid SV.sub.2, whereby the metering chamber shutter 10 is opened to allow the ice pieces to be dispensed from the metering chamber 13, as will be seen in FIG. 7 at (b).

The contact TM.sub.2-1 of the activated timer TM.sub.2 is opened with the contact TM.sub.2-2 being closed at a time point T.sub.2 after a lapse of the time T.sub.2 starting from the activation of the secnd timer TM.sub.2.

When the contact TM.sub.2-1 of the second timer TM.sub.2 opens, the second relay X.sub.2 is deenergized, whereby the discharge port shutter actuator SV.sub.1 and the drive motor 2 are deenergized. Thus, the agitator assembly 6 is stopped with the discharge port shutter 9 being closed.

Additionally, when the contact TM.sub.2-2 of the second timer TM.sub.2 is closed, the third timer TM.sub.3 is activated. After a lapse of a very short time T.sub.3 starting from the activation of the third timer TM.sub.3, the contact TM.sub.3-1 is opened with the contact TM.sub.3-3 being closed at a time point T.sub.4.

When the contact TM.sub.3-1 is opened, the first timer TM.sub.1 is released from the self-holding state. Consequently, the contact TM.sub.1-2 of this timer is opened, whereby the second timer TM.sub.2 is deactivated. Furthermore, the contact TM.sub.1-3 is opened to deenergize the third relay X.sub.3, while the third timer TM.sub.3 itself is also instantaneously deactivated in response to the opening of the contact TM.sub.2-2. When the third relay X.sub.3 is deenergized, the metering chamber shutter actuator SV.sub.2 is also deenergized to allow the metering chamber shutter 10 to to be closed while the discharge port shutter 9 is again opened because the contact TM.sub.2-1 is restored due to the deenergization of the second timer TM.sub.2, as will be seen in FIG. 7 at (b). By interposing a short delay time T.sub.3 between the closing of the discharge port shutter 9 and that of the metering chamber shutter 10, the ice pieces are prevented not only from being clamped by the metering chamber shutter sheet 10 but also from being left within the metering chamber 13.

Furthermore, when the contact TM.sub.3-2 is closed, a signal is applied to the input terminal In of the counter CNT. Since the third timer TM.sub.3 is deenergized immediately after having been energized as described above, the signal applied to the input terminal In through the contact TM.sub.3-2 is naturally a needle-like pulse signal. In response to this pulse signal, the counter CNT is incremented to indicate that the ice dispensing operation has been performed once.

When the first timer TM.sub.1 is released from the self-holding state, the second timer TM.sub.2 is also deactivated to close the contact TM.sub.2-1 thereof, whereupon the second relay X.sub.2 for the ice discharge operation is again energized to allow the ice pieces to be transferred to the metering chamber for being subsequently dispensed. This operation may be repeated a number of times as desired.

In this manner, the ice discharging/dispensing operation is repeated until the number of the pulses produced by the contact TM.sub.3-2 has attained the value preset in the counter CNT, whereupon the contact S.sub.CNT of the counter CNT is opened, resulting in that the fifth relay X.sub.5 for holding the ice dispensing operation is released from the self-holding state. The ice dispensing operation now comes to an end.

In conjunction with the embodiment shown in FIG. 8, it should be noted that the opening/closing operations of the discharge port shutter and the metering chamber shutter may be controlled by either the control circuit shown in FIGS. 4A and 4B or the one shown in FIGS. 6A and 6B.

As will be appreciated from the foregoing description, the ice dispenser apparatus according to the present invention is so arranged that during an ice dispensing operation, the ice pieces discharged from the ice storage box are stored once in the metering or transient storage chamber in a predetermined amount and that the ice dispensing operation can be repeated a number of times depending on the amount of ice desired. With such an arrangement unevenness in the amount of dispensed ice can be suppressed to a minimum regardless of possible changes in the nature or quality and shape of the ice pieces to thereby ensure consistent ice dispensing operation performance of the ice dispenser apparatus. The apparatus according to the present invention can thus be applied to automatic vending machines or the like to facilitate a great advantage and effectiveness.

The invention and many of its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the form, construction and arrangement thereof without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred or exemplary embodiment thereof.