Drinking water dispenser

A drinking water dispenser heats and cools drinking water supplied from a water supply bottle, and provides heated and cooled drinking water. The dispenser includes a cold water tank, a hot water tank, a water supply pipe, a valve, a by-pass pipe, a by-pass valve and a control unit. The valve opens and closes a water outlet for taking in the drinking water from the water supply bottle according to a level of the drinking water in the cold water tank, limits supply of the drinking water to the cold water tank, and, while the water outlet is shut, suppresses convection of the drinking water and/or heat of the drinking water between the water supply bottle and the cold water tank.

BACKGROUND OF THE INVENTION

i) Field of the Invention

The present invention relates to a drinking water dispenser that cools drinking water provided by the bottle to dispense cold water, or heats the drinking water to dispense hot water.

ii) Description of the Related Art

A drinking water dispenser (water dispenser) for cooling or heating, and dispensing drinking water, such as mineral water, supplied from a bottle is commonly used. For example, this drinking water dispenser is used for drinking water supply not only in an office but also in a home.

It is known concerning such a drinking water dispenser that drinking water heated in a hot water tank is circulated in a cold water tank (for example, Japanese Laid-Open Patent Publications No. 2005-249266 and 2009-046150).

It is also known that convection of water or temperature is suppressed between a bottle which supplies drinking water and a cold water tank (for example, Japanese Laid-Open Patent Publication No. 2009-196650).

BRIEF SUMMARY OF THE INVENTION

When purification of drinking water is carried out with circulation of water, which is heated in a hot water tank, in a cold water tank of a drinking water dispenser using, e.g., natural convection, complication of a circulation route for the water causes the circulation rate to decrease, which necessitates a long time for the purification.

When a circulation route of drinking water in a drinking water dispenser is simplified and, e.g., a bottle for supplying drinking water is made to approach a cold water tank, there is a risk of heated drinking water, which circulates in the cold water tank, and its heat convecting to drinking water of room temperature in the bottle.

An object of the drinking water dispenser of the present disclosure is, in a purification process, to prevent drinking water in a bottle from being heated by convection of heated drinking water or its heat to the bottle.

Another object of the drinking water dispenser of the present disclosure is to prevent a purification function from deteriorating due to heated drinking water convecting to drinking water in a bottle to lower the temperature of circulating drinking water.

The drinking water dispenser of the present disclosure is a drinking water dispenser that heats and cools drinking water supplied from a water supply bottle, and provides heated and cooled drinking water, and that includes a cold water tank, a hot water tank, a water supply pipe, a valve, a by-pass pipe, a by-pass valve and a control unit. The cold water tank cools the drinking water to store the cooled drinking water. The hot water tank heats the drinking water to store the heated drinking water. The water supply pipe introduces the drinking water supplied to the cold water tank, to the hot water tank. The valve opens and closes a water outlet for taking in the drinking water from the water supply bottle according to a level of the drinking water in the cold water tank, limits supply of the drinking water to the cold water tank, and, while the water outlet is shut, suppresses convection of the drinking water and/or heat of the drinking water between the water supply bottle and the cold water tank. The by-pass pipe is between the hot water tank and the cold water tank, along with the water supply pipe, to circulate the heated drinking water in the hot water tank and the cold water tank. The by-pass valve blocks the by-pass pipe. The control unit controls open and close of the by-pass valve while there is no provision request of the drinking water and while the valve is shut.

The drinking water dispenser of the present invention may further include cooling means, heating means, cold water temperature detecting means and hot water temperature detecting means. The cooling means is placed on the cold water tank, and cools the drinking water. The heating means is placed on the hot water tank, and heats the drinking water. The cold water temperature detecting means detects a temperature of the drinking water in the cold water tank. The hot water temperature detecting means detects a temperature of the drinking water in the hot water tank. When the drinking water is circulated, the control unit may stop the cooling means and operate the heating means to heat the drinking water to a predetermined temperature or over.

The drinking water dispenser of the present invention may further include a separating plate. The separating plate separates the drinking water in the cold water tank into an upper layer side and a lower layer side. The water supply pipe may be connected to an opening of the separating plate, and make the drinking water, that falls onto the separating plate from the water outlet, flow to the hot water tank.

In the drinking water dispenser of the present invention, the valve may further include a float part and an open and close part. The float part rises and falls according to the level of the drinking water in the cold water tank. The open and close part is placed on the float part and opens and closes the water outlet. An air layer may be formed between the water outlet and a water surface of the cold water tank of a full level by shutoff of the water outlet.

In the drinking water dispenser of the present invention, the float part and the open and close part may be formed by a ball tap.

The drinking water dispenser of the present invention may further include a water level detector. The water level detector detects the level of the drinking water in the cold water tank. The valve may be formed by an open and close valve that opens and closes the water outlet. The control unit may open and close the open and close valve according to a result of detection of the water level detector.

Other objects, features and advantages of the present invention will become clearer with reference to attached drawings and each embodiment.

DETAILED DESCRIPTION OF THE INVENTION

First Embodiment

According to a first embodiment, a purification process is carried out in a drinking water dispenser with heating and circulating drinking water in the drinking water dispenser during a predetermined timing. The drinking water dispenser provides a valve that limits supply of drinking water according to the water level, and that, in a purification process, suppresses an inflow of the drinking water and convection of heat to a bottle.

The first embodiment will be described with reference toFIGS. 1 and 2.FIG. 1depicts an example of an internal structure of the drinking water dispenser according to the first embodiment, andFIG. 2depicts an example illustrating a cold water tank from a top view. Each structure depicted inFIGS. 1 and 2is an example, and is not limited to this example.

A drinking water dispenser2is an example of the drinking water dispenser of the present disclosure. The drinking water dispenser2receives supply of drinking water6from a bottle4, and cools the drinking water6to provide cold water or heats the drinking water6to provide hot water. This drinking water dispenser2includes, for example, the bottle4, a cold water tank8, a hot water tank10, a water supply pipe12, a separator float14and a by-pass pipe16.

The bottle4is an example of a supplying means of drinking water to the drinking water dispenser2. For example, the bottle4is mounted on the top of the drinking water dispenser2, and supplies the drinking water6to the cold water tank8using a difference in height. The separator float14is opened and closed as described below, which causes the supply of the drinking water6from the bottle4to the cold water tank8to be limited to a predetermined water level in the cold water tank8.

The cold water tank8is an example of a means for cooling and storing the drinking water6supplied from the bottle4. For example, the cold water tank8provides a separating plate18, a cold water detector20, etc. for its inside, provides a cover22and an evaporator24for its outside, and is connected to a cold water dispensing pipe26.

The separating plate18is a means for separating the drinking water6, which is stored in the cold water tank8, into an upper layer and a lower layer. For example, a gap30is formed between an exterior tube28of the cold water tank8and the separating plate18as depicted inFIG. 2. The gap30is for letting the supplied drinking water flow to the lower layer of the cold water tank8. Such separation by the separating plate18can limit convection of the cooled drinking water6to the upper layer of the cold water tank8.

For example, an opening32and a recessed portion34are formed in the center portion of the separating plate18. The opening32is formed like a pipe line extending to the bottom of the cold water tank8, and connects to the water supply pipe12. The opening32guides some of the supplied drinking water6to the water supply pipe12to supply the drinking water6to the hot water tank10. The recessed portion34is an example of a means for forming a niche for the fallen separator float14as described below, and for receiving the drinking water6, which drips down from the bottle4to be supplied to the cold water tank8, and guiding the drinking water6to the opening32.

The cold water detector20is an example of a water temperature detecting means for the drinking water6in the cold water tank8. This cold water detector20monitors the situation where the drinking water6in the cold water tank8is cooling to a setting temperature in drinking water dispensing driving. In a purification process. for drinking water described below, the cold water detector20monitors the temperature of the drinking water6, which circulates in the cold water tank8, reaching a temperature set in a purification mode.

The cover22is part of a housing of the drinking water dispenser2. The cover22is placed in the upper side of the cold water tank8, holds a valve38for opening and closing a water outlet36of the bottle4, and provides an air intake102for taking in/out the air to/from the cold water tank8(FIG. 3).

The evaporator24is an example of a means for cooling the drinking water6in the cold water tank8. For example, the evaporator24connects to a refrigerant pipe40for letting a refrigerant flow to the center or underneath of the outside of the cold water tank8. This evaporator24provides cooling equipment42for the bottom of the drinking water dispenser2. For example, this cooling equipment42consists of a compressor44, a dryer46and a condenser48. A capillary tube50is placed in the middle of the refrigerant pipe40. The refrigerant pipe40passes between the cooling equipment42and the evaporator24to circulate a refrigerant. This circulation of a refrigerant cools the drinking water6in the cold water tank8.

The cold water dispensing pipe26is a means for letting the drinking water6, which is cooled in the cold water tank8, flow to the cold water dispensing port52. The cold water dispensing pipe26lets the drinking water6flow according to a water dispensing request by a user. For example, this cold water dispensing pipe26provides a cold water solenoid valve54. The cold water solenoid valve54is a means for controlling dispensing the drinking water6and the flow rate of the drinking water6using the opening control thereof. For example, a user's press of a water dispensing button etc. causes the cold water solenoid valve54to open and close.

As much as the drinking water6dispensed from the cold water dispensing port52is supplied from the bottle4to the cold water tank8.

The hot water tank10is an example of a means for heating and storing the supplied drinking water6, and placed below the cold water tank8. For example, this hot water tank10provides a hot water heater56, a hot water dispensing pipe58, etc. for its outside, and a hot water detector60for its inside. The hot water tank10also provides a drain pipe62for drainage.

The hot water heater56is an example of a means for heating the drinking water6in the hot water tank10. For example, the hot water heater56heats the drinking water6in the hot water tank10to a setting temperature in the water dispensing driving. In the purification process described below, the drinking water6that flows from the cold water tank8to the hot water tank10is heated to a predetermined temperature.

The hot water dispensing pipe58is a means for letting the drinking water6, which is heated in the hot water tank10, flow to the hot water dispensing port64. The hot water dispensing pipe58lets the drinking water6flow according to the water dispensing request by a user. For example, this hot water dispensing pipe58provides a hot water solenoid valve66. The hot water solenoid valve54controls dispensing the drinking water6and the flow rate of the drinking water6using the opening control thereof. That is, a user's press of a water dispensing button etc. causes the hot water solenoid valve66to open and close, for example.

The water supply pipe12is an example of a pipe line that guides the drinking water6from the cold water tank8to the hot water tank10. As described above, this water supply pipe12connects to the opening32that is provided for the separating plate18in the cold water tank8, to be inserted into the ceiling of the hot water tank10.

As much as the drinking water6dispensed from the hot water dispensing port64is supplied from the cold water tank8to the hot water tank10. Simultaneously, the drinking water6is supplied from the bottle4to the cold water tank8since the supply of the drinking water6to the hot water tank10reduces the drinking water6in the cold water tank8.

The hot water detector60is an example of a means for detecting the temperature of the drinking water6in the hot water tank10. This hot water detector60monitors heating of the drinking water6in the hot water tank10at a setting temperature in the drinking water dispensing driving. In the purification process for the drinking water6described below, the hot water detector60monitors the temperature of the drinking water6, which circulates in the hot water tank10, reaching a temperature set in the purification mode.

Anything capable of monitoring the temperature of the drinking water6in the cold water tank8and the hot water tank10may be used as the cold water detector20and the hot water detector60. For example, a thermistor thermometer may be used.

The drain pipe62is an example of a means for draining water etc. including the drinking water6in the drinking water dispenser2. For example, the drain pipe62is placed in the bottom of the hot water tank10. A drainage solenoid valve68is placed in the drain pipe62, and a draining process is carried out according to draining instructions etc. The drain solenoid valve69may open and the draining process may be carried out also when there is no water dispensing request to the drinking water dispenser2for more than a predetermined time period or predetermined days, for example.

The separator float14is an example of the valve38for controlling the supply of the drinking water6from the bottle4to the cold water tank8. The separator float14is floating on the drinking water6in the cold water tank8. A rise and fall of the separator float14according to the water level in the cold water tank8causes the water outlet36for taking in the drinking water6to open and close.

The by-pass pipe16is an example of a pipe line that connects the cold water tank8and the hot water tank10. The by-pass pipe16forms a circulation route for the heated drinking water6in the purification process for the drinking water6described below. For example, the by-pass pipe16provides a by-pass valve70to prevent the drinking water6from circulating in the cold water tank8and the hot water tank10in the water dispensing driving. For example, as depicted inFIG. 2, this by-pass pipe16may be positioned opposite to the cold water dispensing pipe26in the cold water tank8using the opening32of the separating plate18as the center.

It is better to position the by-pass pipe16apart from the opening32of the separating plate18. For example, the opening32of the separating plate18is formed upper than the by-pass pipe16, and the by-pass pipe16connects to the bottom of the cold water tank8. This can prevent a short-cycle between the by-pass pipe16and the water supply pipe12in circulation of the drinking water6for purification.

This drinking water dispenser2further provides a control device72for controlling the water dispensing driving and the purification process.

Principles of drinking water supply from the bottle to the cold water tank and a structure of the valve will be described with reference toFIGS. 3,4,5,6,7,8A and8B.FIG. 3depicts an example of a structure of a water supply portion of the drinking water dispenser,FIG. 4depicts an example of a structure of an air intake unit,FIG. 5depicts a supply state of drinking water from the bottle to the drinking water dispenser,FIG. 6depicts airflow under the supply state of drinking water from the bottle to the drinking water dispenser,FIG. 7depicts a shut state of the water outlet with the separator float, andFIGS. 8A and 8Bdepict an example of open and close of the water outlet according to a rise and fall of the separator float. Each structure depicted inFIGS. 3,4,5,6,7,8A and8B is an example, and is not limited to this example.

The drinking water dispenser2provides a mount80for its ceiling. This mount80is a means for the bottle4to be mounted on, and for holding the bottle4so that a water supply port82of the bottle4is connected to a drinking water intake unit84of the drinking water dispenser2.

The drinking water intake unit84provides a projection86that is formed from the cover22, and the valve38. This projection86is an example of a drinking water intake means, and is formed to be hollow. One end of the projection86has the water outlet36for pouring the drinking water6to the cold water tank8, and a side of the other end of the projection86has an inlet88for taking in the drinking water6in the bottle4.

The bottle4is placed on the mount80, so that the projection86penetrates a water supply valve90in the water supply port82of the bottle4to be ready to supply the drinking water6.

The valve38is a means for opening and closing the water outlet36to control an inflow of the drinking water6, and, in the closed state, for preventing the drinking water6and its temperature from convecting between the bottle4and the cold water tank8. For example, this valve38provides the separator float14that rises and falls according to the level of the drinking water6in the cold water tank8, and a float cover92that connects to the cover22.

The separator float14is a convection preventing means as well as an inflow control means for the drinking water6as described above. The separator float14provides a float part94in its lower side and a packing96, which forms an open and close part of the water outlet36, in its upper side. The float94is a means for letting the separator float14rise and fall according to the level of the drinking water6that is stored in the cold water tank8. The packing96is an example of a means for cutting off the drinking water6, which is supplied to the cold water tank8, by touching the water outlet36due to a rise of the separator float14. According to such a structure, the water outlet36is shut as the cold water tank8has a predetermined water level, and the supply of the drinking water6from the bottle4is stopped.

The float cover92is an example of a means for guiding the separator float14which rises and falls. For example, the float cover92has lattice. The drinking water6flows into the cold water tank8through the lattice.

The drinking water dispenser2further provides an air intake unit100for the cover22, for example. This air intake unit100is an example of a means for taking in the air from the outside to the cold water tank8. For example, the air intake unit100consists of the air intake102formed in the cover22, a filter housing104and a filter106as depicted inFIG. 4. The filter housing104is made of tubular metal fittings, for example. The filter106is obliquely attached to the interior of the filter housing104, close to the outside. Thereby, the filler106can be prevented from being clogged with condensation originating from expanding and moist air. A through hole may be provided for the bottom in order to discharge condensation to the outside.

This filter106is a means for preventing impurities etc. from being mixed in the cold water tank8. For example, the filter106may be formed by an antibacterial material or anything having a bacterial filtration function, such as a polyethylene hollow fiber membrane having the pore size of 0.1 μm. The filter106may be formed by a membrane filter (polytetrafluoroethylene (PTFE) material: porous film filter) as well.

As depicted inFIG. 5, the water level in the cold water tank8falls, the separator float14falls, and then the supply of the drinking water6from the bottle4to the cold water tank8is started. The drinking water6in the bottle4goes into the projection86through the inlet88, flows from the water outlet36toward the separator float14, and is stored in the cold water tank8.

For example, the drinking water6flowing into the cold water tank8flows toward the recessed portion34of the separating plate18. Then, the drinking water6flows from the recessed portion34along the separating plate18through the gap30(FIG. 2) toward the lower layer of the cold water tank8. The drinking water6stored in the recessed portion34of the separating plate18flows from the opening32through the water supply pipe12toward the hot water tank10.

When the drinking water6is supplied, air108in the drinking water dispenser2passes through the float cover92from the air intake unit100, and flows into the bottle4via the inside of the projection86as depicted inFIG. 6, for example. The air108flowing into the bottle4permits the drinking water6to be supplied from the bottle4to the cold water tank8. That is, the drinking water6flowing out of the water outlet36causes a negative pressure inside the bottle4. An outflow of the drinking water6is once stopped by an inflow of the air (breath) for the negative pressure, and the air108is taken into the bottle4from the air intake102. When the negative pressure is relieved, the outflow of the drinking water6is stated. Such an outflow of the drinking water6and inflow of the air108are alternately repeated.

When the hot water tank10becomes full and the water level in the cold water tank8rises, the separator float14that is a convection suppressing means floats according to the water level in the cold water tank8. As depicted inFIG. 7, the packing96touches the water outlet36to block the outflow of the drinking water6and suction (inflow) of the air. In this case, the packing96is positioned higher than the float part94, and the level of the drinking water6is lower than the water outlet36. Thus, an air layer110is formed between the water outlet36and the drinking water6under a water cut-off state. Thereby, the supply of the drinking water6is stopped, and thermal convection due to a temperature difference between the bottle4and the cold water tank8can be prevented.

The separator float14which rises and falls according to the water level in the cold water tank8functions as the valve38when the packing96adheres to the water outlet36as depicted inFIG. 8A. For example, the packing96which adheres to the water outlet36is formed by flexible silicone, and has as much hardness as the packing96can adhere with buoyancy of the separate float14. For example, the bottom end of the water outlet36which adheres to this packing96may be flat.

For example, the separator float14is formed to be hollow in order that sufficient buoyancy is generated. This separator float14may be formed by a material which has water resistance, from which buoyancy is obtained, and which has enough weight against surface tension generated between the drinking water6and the packing96. For example, the separator float14may be formed by resin or resin foam.

Consumption of the drinking water6in the cold water tank8or the hot water tank10causes the water level in the cold water tank8falls, and then, the separator float14also falls. When the packing96loses its retention brought by buoyancy, the packing96is released from the state of adhering to the water outlet36and the drinking water6flows from the bottle4into the cold water tank8(FIG. 8B).

The purification process of the drinking water6will be described with reference toFIG. 9.FIG. 9depicts a flow of the drinking water in the drinking water dispenser in the purification process. A structure depicted inFIG. 9is an example, and is not limited to this example. InFIG. 9, the same structure as that ofFIG. 1is denoted by the same reference numerals, and description thereof is omitted.

The purification of the drinking water6is to circulate the drinking water6in the cold water tank8and the hot water tank10to heat the drinking water6to a high temperature. For example, thermal convection is used for this circulation: this thermal convection is generated by the temperature difference between the drinking water6in the cold water tank8and the drinking water6in the hot water tank10. This circulation causes the temperature of the drinking water6in the cold water tank8to rise to a temperature necessary for the purification.

In a circulation process of the drinking water6, the by-pass valve70provided for the by-pass pipe16is opened, and a circulation loop is formed through the hot water tank10, the by-pass pipe16, the cold water tank8and the water supply pipe12. In this circulation loop, the drinking water6of a high-temperature flows into the cold water tank8through the by-pass pipe16, and the drinking water6of a low temperature in the cold water tank8flows into the hot water tank10through the water supply pipe12, for example (an arrow A of a solid line inFIG. 9). As time elapses, the cold water tank8is filled with hot water from the hot water tank, the temperature thereinside becomes high, and the upper air in the cold water tank8expands. For example, this expanding air may be released via the air intake102to the outside.

During execution of this purification process, the separator float14that is a convection suppressing means continues to shut the water outlet36, which prevents the drinking water6in the bottle4from being heated. When a purification operation is ended and the inside of the cold water tank8is cooled, an intake of released air causes the air layer110to be kept (FIG. 7), and the separator float14can keep water cut off.

In the purification process, the temperature of the drinking water6in the cold water tank8is monitored by the cold water detector20. For example, this cold water detector20is positioned apart from the by-pass pipe16as depicted inFIG. 2. Thereby, an anomaly in circulation can be detected from measured time, a detected change in temperature, etc. even if a short-cycle occurs, that is, hot water circulates in only part of the cold water tank8to form layers of hot water and cold water, for example.

A direction of the circulation is not limited to the arrow A of a solid line inFIG. 9. There also may be a case that the drinking water6of a high-temperature flows from the water supply pipe12through the cold water tank8and the by-pass pipe16to the hot water tank10as depicted in an arrow B of a dotted line. At the same time, the drinking water6of a low-temperature flows into the hot water tank10. According to such a case, the purification process of the drinking water6in the cold water tank8also can be carried out.

An external structure of the drinking water dispenser will be described with reference toFIG. 10.FIG. 10depicts an example of the external structure of the drinking water dispenser. The structure depicted inFIG. 10is an example, and is not limited to this example.

For example, this drinking water dispenser2provides a display and operation part120for its upper front surface, and a water dispensing window122for its middle front surface. The display and operation part120provides a kind of a switch of instructing operation input etc. and a display of displaying a driving status etc., for example. The cold water dispensing port52and the hot water dispensing port64are installed inside the water dispensing window122. A mount124is formed below these cold water dispensing port52and hot water dispensing port64in order for a cup etc. for receiving the dispensed drinking water6to be mounted on. For example, a drain means for the drinking water6may be provided for this mount124.

Examples of structures of the display and operation part120and the control device72, and an example of operation control of the drinking water dispenser2will be described with reference toFIGS. 11A,11B and12.FIGS. 11A and 11Bdepict an example of a structure of the display and operation part of the drinking water dispenser, andFIG. 12depicts an example of a structure of the control device. Each of arrangement and processing contents depicted inFIGS. 11A,11B and12is an example, and is not limited to this example.

The display and operation part120is an example of a means for operating setting instructions etc., and a means for displaying setting information, time information, etc. of the drinking water dispenser2. For example, this display and operation part120provides an addition switch126, a subtraction switch128, a setting switch130, an energy-saving switch132, a timer and clock switch134, a start and stop switch136, etc. The display and operation part120also provides a high-temperature setting switch138, a cold water setting switch140, a hot water dispensing switch142, an unlocking switch144, a cold water dispensing switch146, etc.

The addition switch126or the subtraction switch128is an example of a means for adding or subtracting a setting input value. The setting switch130is a means for input instructions of switching and cancelling a setting mode. The energy-saving switch132is a means for instructing operation of setting and cancelling an energy-saving mode, where in a preset time zone etc., heating and cooling temperatures of the drinking water6are limited, for example. The timer and clock switch134is a means for inputting a setting of a timer200(FIG. 12) and adjustment of time information. The start and stop switch136is a means for instructing start or stop of the timer200, the setting of which has been inputted, and an operation mode. The high-temperature setting switch138is an example of a means for instructing a forcible change of water heating temperature, that is, a means for instructing a shift to a high-temperature setting different from normal driving (for example, 85° C.) or cancelling that instruction. The cold water setting switch140is an example of a means for instructing a forcible change of water dispensing temperature, that is, a means for instructing a shift to a cold water setting different from normal driving (for example, 8° C.) or cancelling that instruction. The hot water dispensing switch142is an instruction means for starting to dispense the heated drinking water6from the hot water dispensing port64. The cold water dispensing switch146is an instruction means for dispensing water from the cold water dispensing port52. The unlocking switch144is a means for permitting input operation to the hot water dispensing switch142and the cold water dispensing switch146, which are locked.

For example, the display and operation part120also provides a display148, a display for high-temperature water auto circulation mode150, a display for normal hot water dispensing temperature152, a high-temperature display154, a display for normal water dispensing temperature156, a mild temperature display158, an unlocking display160, an energy-saving display162, etc.

The display148is an example of a means for displaying time etc. For example, a time display170, a timer display172, stage displays174and176, a start display178and an end display180are set on the display148as depicted inFIG. 11B. For example, the time display170displays setting contents such as starting time of the purification process or the energy-saving mode in addition to normal clock display. The display for high-temperature water auto circulation mode150is a means for informing a user that the purification process using hot water circulation is being carried out. The display for normal hot water dispensing temperature152is an example of a means for indicating a setting of, for example, 85° C. as a normal water heating driving mode. The high-temperature display154is a means for displaying that water heating temperature is set high. The display for normal water dispensing temperature156is an example of a means for indicating a setting of, for example, 8° C. as a normal water dispensing mode. The mild temperature display158is a means for displaying that a water dispensing temperature is set mild, for example, in 12° C. The unlocking display160is a means for indicating whether the hot water dispensing switch142or the cold water dispensing switch146is unlocked by the unlocking switch144. The energy-saving display162is a means for indicating that the energy-saving mode is running with a press of the energy-saving switch132. These display means other than the display148consist of a lamp, for example, an LED (Light Emitting Diode). Liquid crystal display elements may be used for the display148.

For example, the control device72of the drinking water dispenser2takes in information detected by the cold water detector20, the hot water detector60, etc., and performs various kinds of control such as cooling control, heating control, energy-saving control and the purification process. This control device72is composed of a control unit190that is made of a microcomputer and so on, and connected to the display and operation part120as depicted inFIG. 12. For example, in the control unit190, a processor192, an I/O (input/output) part194, a storage part196, a RAM (Random Access Memory)198and the timer200are connected to each other via a bus202.

The processor192is composed of a CPU (Central Processing Unit) or an MPU (MicroProcessor Unit), and performs arithmetic processing of an OS (Operating System) and an operation program which are stored in the storage part196. The I/O part194is an example of an interface for input and output of the control unit190, and for example, takes in temperature information detected by the cold water detector20and the hot water detector60. An operation control signal is also outputted through the I/O part194to the hot water heater56, the hot water solenoid valve66, the cold water solenoid valve54, the compressor44, the by-pass valve70, etc. Further, operation instructions inputted from the display and operation part120are taken in, and a display control signal, etc is outputted also.

The storage part196is composed of a ROM (Read Only Memory). The storage part196is made up of a program storage part that stores an OS executed by the processor192, an operation program of the drinking water dispenser2, etc., and a data storage part that stores detected temperature information etc. The RAM198functions as a working area for processing the above operation program. The timer200is a time measuring means or a means for obtaining time information. For example, the timer200obtains time information on the operation control as well as carrying out a time measuring process as an interval timer described below.

A power source204that executes power feeding control of the drinking water dispenser2, a buzzer206as an example of an informing means in case of an anomaly in operation, etc. may be connected to this control device72.

An example of control by the control device72will be described below.

When a power is turned on, the cooling equipment42for cooling the drinking water6is turned ON (for example, setting temperature: 8° C.) and the power feeding control over the hot water heater56for heating the drinking water6is turned OFF. In this case, operation for the unlocking switch144and the hot water dispensing switch142may be accepted in order to keep the availability of water heating. It is noted that when the power feeding control over the hot water heater56is under an OFF state, a temperature detected by the hot water detector60is a predetermined temperature, for example, 40° C. or below.

As to clock display of the display148, an hour and a minute are displayed with blinking display of “--:--”. A press of the addition switch126, the subtraction switch128and the setting switch130determines time of the clock display.

The power feeding control over the hot water heater56is carried out when the start and stop switch136is pressed for a long time, for example, two seconds. A setting temperature during ON operation is set in 85° C., for example. A press for a long time, for example, two seconds in an ON state leads to the OFF state. If the hot water detector60uses a thermistor, the presence or not of the drinking water6can be determined using a self-heating characteristic of the thermistor to switch ON/OFF the power feeding control over the hot water heater56.

As the power feeding control over the hot water heater56is shifted from the OFF state to the ON state, the energy-saving mode is into the OFF state. The same control is carried out when a power outage state is restored to a power feeding state. If time of the energy-saving mode is set, the time is stored in the storage part196.

A time setting is carried out in a clock display mode. A time setting of the energy-saving mode is carried out in an energy-saving time setting mode.

B) Cold Water Dispensing Operation

When the cold water dispensing switch146is continuously pressed under a state of permitting the instructions thereof (unlocked), the cold water solenoid valve54is controlled into an opened state, and cold water is started to be dispensed. While the cold water dispensing switch146is pressed, this cold water solenoid valve54is controlled into the opened state and the operation of the hot water dispensing switch142is not accepted. That is, safety is secured because cold water and hot water are not concurrently dispensed.

C) Cold Water Switching Operation

If the cold water setting switch140is continuously pressed, a setting of a cold water temperature is changed. For example, the setting temperature is changed as follows: 8° C.->12° C.->8° C. . . . .

If the unlocking switch144is pressed, the hot water dispensing switch142and the cold water dispensing switch146are unlocked, and the press thereof is permitted. In this time, the unlocking display160which is set on the unlocking switch144lights up in red and an unlocked state is displayed. Time limit is set for this unlocking. For example, if there has been no operation of the hot water dispensing switch142for 10 minutes, the unlocking display160is extinguished, and the unlocked state is switched to a locked state.

If the unlocking switch144is pressed again during unlocked, the unlocking display160is extinguished, and the unlocked state shifts to the locked state.

If dispensing hot water or cold water is ended and the press of the hot water dispensing switch142or the cold water dispensing switch146is stopped, the unlocking display160is extinguished after, for example, 10 seconds from this stop, and the unlocked state is into the locked state again.

E) Hot Water Dispensing Operation

If the hot water dispensing switch142is continuously pressed under its permitted state (unlocked), hot water solenoid valve66is into an opened state to dispense hot water. The hot water solenoid valve66is the opened state while the hot water dispensing switch142is pressed. While the hot water dispensing switch142is pressed, the operation of the cold water dispensing switch146is not accepted. That is, a process following a prior press of the hot water dispensing switch142or the cold water dispensing switch146is prioritized.

The high-temperature setting switch138functions when the power feeding control over the hot water heater56is ON. The drinking water6in the hot water tank10is heated to a predetermined high-temperature, for example, 93° C. After this heating, predetermined hot water temperatures, for example, a range of 90° C. and the predetermined high-temperature is set as a proper temperature range of the high-temperature setting. After that, the setting temperature is switched to 85° C., for example. The high-temperature display154is lit in orange during the heating of the high-temperature setting. Informing by the buzzer206for a predetermined time, for example, ten seconds may be carried out as soon as the temperature of the high-temperature setting is reached. When the temperature of the high-temperature setting is reached, the high-temperature display154is lit in green and the power feeding to the hot water heater56is turned OFF. If hot water is within a high-temperature range (90° C. or over), the display of the high-temperature display154is continued.

When the high-temperature setting switch138is pressed during the high-temperature heating, the heating is suspended. After the heating, the power feeding to the hot water heater56is turned off. If the high-temperature setting switch138is pressed again, heating to the above described setting temperature, 93° C. is carried out. In this case, the high-temperature display154is lit in orange even if the temperature of hot water is within range of 90° C. and 92° C. If hot water is within the proper temperature range (85° C. and 89° C.) after the heating, the display for normal hot water dispensing temperature152is lit in green to display that the temperature is within the proper temperature range.

If the power feeding control over the hot water heater56is OFF, the press of the energy-saving switch132is not accepted. When the energy-saving switch132is pressed under the ON state of the power feeding over the hot water heater56, the energy-saving mode is started to run, and the energy-saving display162lights up in orange to display that the energy-saving mode is in the execution. If the energy-saving switch132is pressed in the energy-saving mode, the energy-saving mode is canceled and the energy-saving display162is extinguished.

When the energy-saving mode is in the execution and it is setting time of an energy-saving process, the energy-saving process is carried out and the energy-saving display162is lit in green.

H) Timer and Clock Operation

If the timer and clock switch134is pressed, the display148is changed from clock display to timer display to shift to a timer mode. If the timer and clock switch134is pressed in the timer mode, the display148shifts to the clock display. It is noted that when the timer200counts down, this counting may be continued.

I) Addition Operation, Subtraction Operation, Start and Stop Operation and Setting Operation

If the addition switch126or the subtraction switch128is continuously pressed during a time setting mode or switching of the timer display, time or time periods for the timer is changed.

If the start and stop switch136is pressed during the timer display (stand-by), the timer200starts counting. If the start and stop switch136is pressed while the timer200is counting down, the counting down is suspended. A press of the start and stop switch136again restarts the counting down.

If the setting switch130is pressed, determination in the time setting is carried out, and the energy saving mode is started. The press of the setting switch130after start of a process in the execution ends this process to enable a setting to be switched.

J) Clock Display

When the power source204is turned ON, the clock display is generated. A continuous press of the timer and clock switch134leads to the time setting mode. In this setting mode, the clock display is blinking. The display is changed by a press of the addition switch126or the subtraction switch128, and a press of the setting switch130or a lapse of a predetermined time determines the setting. For example, a press of the addition switch126changes the time display in the time setting mode as follows: 12:01->12:02->12:03 . . . . A continuous press thereof changes the display as follows, for example: 12:10->12:20->12:30 . . . 13:00->13:30->14:00 . . . 15:00->16:00. As well, a press of the subtraction switch128changes the display as follows, for example: 11:59->11:58->11:57 . . . , and a continuous press thereof changes the display as follows, for example: 11:50->11:40->11:30 . . . 11:00->10:30->10:00 . . . 9:00->8:00.

K) Timer Function

If the timer and clock switch134is pressed, “m” and “s” are displayed on the display148, for example, and the display148becomes the timer display. In this case, for example, 300 is displayed in default. The maximum time period of the timer is 60 minutes, for example. Minute display is changed by a press of the addition switch126or the subtraction switch128during the timer display (stand-by). A press of the addition switch126changes the display as follows: 3->3.30->4->4.30->5 . . . 10->11. The display continuously changes up to the maximum, 60 minutes. A press of the subtraction switch128changes the display as follows: 3->2.30->2->1.30->1->0.30->00. A press of the start and stop switch136starts the timer200counting down. A minute setting can be changed if the addition switch126or the subtraction switch128is pressed during the counting down. When the timer200becomes 0:00, the buzzer206is actuated and a user is informed.

Two stages of settings can be carried out as to energy-saving time, for example. A method for setting the energy-saving time is the same as the time setting. If the settings of these stages are carried out, the energy-saving mode is executed when conditions of a setting are met. An example of the setting for the energy-saving mode will be depicted as follows.

(1) If the power feeding control over the hot water heater56is ON under a clock display state, the stage display174, which represents a first stage, and the start display178are displayed on the display148when the energy-saving switch132is pressed. For example, time display “--:--” is displayed at the first time when a setting has not been carried out. Current time or the time that was set last time may be displayed on a setting screen at the second time and later.

When time is set and the setting switch130is pressed, the stage display176, which represents a second stage, and the start display178are displayed on the display148instead of the display of the stage display174and the end display180. As well, when time is set, the stage display176and the end display180are displayed.

(2) Time can be set by pressing the addition switch126or the subtraction switch128. This setting operation is the same as the time setting.

(3) A press of the setting switch130determines setting contents. The clock display is displayed again after 10 seconds have elapsed since no switch operation is executed during each operation or since operation is ended. If a setting is desired to be canceled, a stage desired to be canceled is selected by the setting switch130, and either the addition switch126or the subtraction switch128is pressed, or both of them are pressed simultaneously. Thereby, “--:--” is displayed on the display148. A press of the setting switch130can determine the setting contents.

Driving control of the drinking water dispenser2will be described with reference toFIGS. 13 and 14.FIGS. 13 and 14is a flowchart depicting an example of the driving control of the drinking water dispenser. Processing contents, procedure, etc. depicted inFIGS. 13 and 14are example. A and B inFIGS. 13 and 14depict connectors between the flowcharts.

This process is an example of a control method of the drinking water dispenser, and depicts an example of control of dispensing hot or cold water, and of control of the purification process of the drinking water dispenser2. In this process, control is executed using elapsed time and time information, for example. This process is repeatedly executed while the drinking water dispenser2is powered on.

After the drinking water dispenser2is powered on, a default value, for example, 72 (hours) is set for a timer for counting the interval of executing the purification process (step S1) other than the initial setting for every part, and counting down is started (step S2).

After the start of counting, whether the start time of the energy-saving mode is set is checked (step S3). If the time is set (YES of step S3), current time information is obtained from the timer200, another clock function, or a clock function outside, for example. In this step S3, to execute the purification process with high-temperature water circulation when the energy-saving mode is executed is determined as one timing of executing the purification process. That is, for example, energy-saving is aimed in the energy-saving mode where a thermal keeping setting temperature of cold and hot water is changed in a time zone when a user does not use, or seldom uses the drinking water dispenser2, such as a midnight time zone. The drinking water6can not be dispensed during the process of the high-temperature water circulation. Thus, dispensing the drinking water6to a user is not interrupted, and the convenience can be increased if the process of the high-temperature water circulation is carried out at the timing of this energy-saving mode.

It is determined whether the current time is within a time zone of the energy-saving mode or not with reference to the obtained time information (step S4). If the current time is within a time zone of the energy-saving mode (YES of step S4), whether to execute the process of the high-temperature water circulation is determined with reference to the start time of the energy-saving mode (step S5). That is, the purification with the high-temperature water circulation is carried out at the timing of switching to the energy saving-mode. This is because the setting temperature in a normal mode has less difference than the setting temperature in the energy-saving mode from the setting temperature of the process of the high-temperature water circulation when the drinking water6is heated. That is, the temperature of the drinking water6in the hot water tank10after a shift to the energy-saving mode is lower than that in the normal mode, and in that case, further heating that is capable of raise the temperature of the drinking water6in the energy-saving mode to that in the normal mode would be necessary to be carried out. Thus, the purification process is carried out at the start timing of the energy-saving mode. The purification process with the high-temperature water circulation needs a certain time. So, whether to execute the process of the high-temperature water circulation is determined with reference to time of starting the energy-saving mode in order to prevent the energy-saving mode from ending during the process of high-temperature water circulation.

In the case of the start time of the energy-saving mode (YES of step S5), whether time is up in the interval timer is determined (step S6). For example, whether the default value set in step S1has elapsed is determined with reference to the timer200. If the time is up in the interval timer (YES of step S6), the process of the high-temperature water circulation is carried out (step S7), and the procedure returns to step S2.

If the energy-saving time is not set (NO of step S3), whether the time is up in the interval timer is determined (step S8). This step S8represents executing the purification process with the high-temperature water circulation during normal driving as one timing of executing the purification process.

If time is up in the interval timer (YES of step S8), it is determined whether the current time is a predetermine time P that is set in advance, for example, 2 a.m. (step S9). This process of the high-temperature water circulation is set so as to be carried out at the predetermined time P after a default value, for example, 3 days (72 hours) elapses. In a case of the predetermined time P (2 a.m.) after time is up in the interval timer (YES of step S9), the process of the high-temperature water circulation is carried out (step S10).

After the end of the process of the high-temperature water circulation, the drinking water6in the hot water tank10is kept the setting temperature (step S11) and the drinking water6in the cold water tank8is kept the setting temperature (step S12) as the normal mode.

If time is not up in the interval timer (NO of step S8) or if it is not the predetermined time P even if time is up in the interval timer (NO of step S9), the procedure shifts to step S11as the normal mode.

If the start time of the energy-saving mode is set (YES of step S3) but it is not within a time zone of the energy-saving mode (NO of step S4), or if the energy-saving mode is not carried out (NO of step S13), the procedure also shifts to step S11for shifting to the normal mode.

If the energy-saving time is set (YES of step S3) but the procedure does not shift to operation of the high-temperature water circulation, the energy-saving switch132is pressed to determine whether an input of executing the energy-saving mode has been carried out (step S13), and the procedure shifts to the energy-saving mode. Examples of a case where the procedure does not shift to the operation of the high-temperature water circulation is a case where time is not up in the interval timer (NO of step S6) and a case of not the start time of the energy-saving mode (NO of step S5). In this energy-saving mode, the drinking water6in the hot water tank10is managed under the setting temperature of the energy-saving mode (step S14) and the drinking water6in the cold water tank8is managed under the setting temperature of the energy-saving mode (step S15).

In temperature management of the normal mode, the temperature of the drinking water6in the hot water tank10is detected by the hot water detector60, and operation control of the hot water heater42is executed so that the temperature becomes the setting temperature, or the temperature of the drinking water6in the cold water tank8is detected by the cold water detector20, and operation control of the evaporator24is executed so that the temperature becomes the setting temperature. In the energy-saving mode, the temperature of the drinking water6in the hot water tank10is managed lower than that of the normal mode, and the temperature of the drinking water6in the cold water tank8is managed higher than that of the normal mode.

In the control of dispensing cold water or hot water, as depicted inFIG. 14, whether the input of dispensing cold water has been executed is determined in both driving states of the normal mode and the energy-saving mode (step S16). This is determined based on detection whether the cold water dispensing switch146has been pressed, for example. If the input of dispensing cold water has been executed (YES of step S16), the procedure shifts to determination whether to be a temperature of permitting to dispense cold water (step S17). This temperature of permitting to dispense cold water is a temperature that is set for preventing the drinking water6of high-temperature from flowing out of the cold water dispensing port52in a case of the water dispensing request just after the operation of the high-temperature water circulation, for example. Therefore, water cannot be dispensed when the cold water detector20detects to be the predetermined temperature, that is set in advance, or over.

If the drinking water6in the cold water tank8is the temperature of permitting to dispense cold water (YES of step S17), the cold water solenoid valve54is opened and water is dispensed (step S18). At this time, counting time of the interval timer is increased by a predetermined time Tx (step S19). As to this increase by the predetermined time Tx, an interval time may be increased according to frequency of water dispensing requests and the dispensing volume of the drinking water6, for example. That is, the purification of the drinking water6in the cold water tank8is executed for preventing the quality of water from changing when the drinking water6of low-temperature stays still without being used for long time. If water is dispensed, the interval time of the purification process is increased because the drinking water6does not stay still in the cold water tank8.

If it is not the temperature of permitting to dispense cold water (NO of step S17) but the unlocking switch144is pressed (YES of step S20) by the operation of a user, for example, water may be dispensed.

If the input of dispensing cold water is not carried out (NO of step S16), or if it is not the temperature of permitting to dispense cold water (NO of step S17) and unlocking is not performed (NO of step S20), the procedure shifts to determination whether an input of dispensing hot water is carried out (step S21). This is determined by whether the hot water dispensing switch142has been pressed by a user, for example.

In a hot water dispensing process, whether to be unlocked or not (step S22) is determined, hot water is dispensed (step S23), and the procedure returns to step S3. If the input of dispensing hot water is not carried out (NO of step S21) or unlocking is not performed (NO of step S22), the procedure also returns to step S3.

The above described default value of the interval timer, the start time of the energy-saving, and the start time of the process of high-temperature water circulation except the energy-saving time are examples set in the drinking water dispenser2in advance. They may be set or changed by a user optionally.

The purification process of the drinking water6with the high-temperature water circulation will be described with reference toFIG. 15.FIG. 15is a flowchart depicting procedure of the purification with the high-temperature water circulation, which is a subroutine.

In this purification process with the high-temperature water circulation, the drinking water6that is heated to a purification temperature Tw, for example, 85° C. or over is circulated in the cold water tank8. Then the circulation process of high-temperature water is carried out for a purification time period X, for example, 30 minutes (step S115to step S116). This purification process also includes a heating process for keeping the temperature of the circulating drinking water6the purification temperature Tw (step S111to step S113), and an anomaly determination process in the purification process and an informing process of an anomaly (step S101to step S102, step S114and step S107to step S108).

At the start of the operation of the high-temperature water circulation, the timer200as an anomaly determination timer for monitoring an anomaly of the purification is reset (step S101) to be started (step S102). In order to raise the temperature of the drinking water6in the cold water tank8, the compressor44that is a cooling means is stopped (step S103) and the hot water heater56is operated (step S104).

After the start of heating the drinking water6by the hot water heater56, it is determined whether the temperature of the drinking water6in the hot water tank10is a circulation start temperature Tb, for example, 90° C. or over (step S105). The circulation start temperature Tb is a preparatory high temperature for generating thermal convection using the difference in temperature. For example, the circulation start temperature Tb may be monitored by the hot water detector60. It is checked whether the hot water heater56functions as a heating means for the process of the high-temperature water circulation by this monitoring of the circulation start temperature Tb.

If the temperature of the drinking water6in the hot water tank10is the temperature Tb or over (YES of step S105), the by-pass valve70is opened (step S106), a circulation loop is formed between the cold water tank8and the hot water tank10, and the circulation of the heated drinking water6is started.

If the temperature of the drinking water6is below the temperature Tb (NO of step S105), it is determined whether anomaly monitoring time Xe of a predetermined time, for example, two hours has elapsed (step S107) with reference to the timer200, which is the anomaly determination timer. A longer time than time necessary for the purification process is set for this anomaly monitoring time Xe, for example. If the time Xe has not elapsed (NO of step S107) based on this determination, the procedure returns to step S105, and the monitoring is continued. If the time Xe has elapsed (YES of step S107), it is determined that there is some anomaly in the hot water heater56, for example, to carry out informing of an anomaly in the high-temperature water circulation (step S108).

After the by-pass valve70is shifted to be an opened state (step S106) to start the circulation, the timer200as a circulation timer for measuring the purification time X is reset (step S109), and then started (step S110). In this case, the timer200, different from the above described anomaly determination timer, measures circulation time.

During the circulation of the drinking water6, it is monitored that the temperature of the drinking water6in the hot water tank10is a predetermined temperature Th, for example, 93° C. or over (step S111). That is, in order to continue the circulation of the drinking water6with thermal convection, it is monitored by the hot water detector60that the drinking water6of high-temperature in the hot water tank10is the predetermined temperature Th or over. If the drinking water6is the predetermined temperature Th or over (YES of step S111), the hot water heater56is stopped (step S112). If the predetermined temperature Th is not reached (NO of step S111), the heating with the hot water heater56is kept (step S113).

It is determined whether the above described time Xe has elapsed since the start of the operation of the high-temperature water circulation (step S114) with reference to the timer200as monitoring the anomaly determination timer. If the time Xe has not elapsed (NO of step S114), the procedure shifts to monitoring of the temperature of the drinking water6in the cold water tank8. If the time Xe has elapsed (YES of step S114), it is determined that some anomaly occurs in the circulation process, and the above described informing of an anomaly in the high-temperature water circulation is carried out (step S108). That is, if the purification process cannot be completed even if the anomaly monitoring time Xe has elapsed, it is determined to be an anomaly in the high-temperature water circulation. For example, this anomaly in the circulation is generated when there is some anomaly in the by-pass pipe16or the by-pass valve70, or when the heated drinking water6is circulated around the cold water tank8in a short cycle.

In the monitoring of the temperature of the drinking water6in the cold water tank8, it is determined whether the temperature of the drinking water6is the purification temperature Tw or over (step S115). This monitoring of the temperature is carried out by the cold water detector20. If the drinking water6is not the purification temperature Tw or over (NO of step S115), the procedure returns to step S109, and the heating process is continued. In a case of the purification temperature Tw or over (YES of step S115), the procedure shifts to determination whether the purification time X has elapsed since the start of measuring the circulation timer (step S110) (step S116).

The monitoring of the temperature of the drinking water6in the cold water tank8is repeated until the purification time X has elapsed under the temperature of the purification temperature Tw or over (NO of step S116). If the purification time X has elapsed (YES of step S116) or informing of an anomaly in the high-temperature water circulation (step S108) is carried out, the procedure shifts to an ending process of the purification process with the high-temperature water circulation. The by-pass valve70provided for the by-pass pipe16is closed (step S117), the default value is set for the interval timer (step S118), counting down is started (step S119), and the operation of the high-temperature water circulation is ended.

According to such a structure, the drinking water6in the cold water tank8, and the drinking water6of high-temperature in the purification or its heat cannot be converted to the bottle. Thereby, a temperature change is not generated in the drinking water6stored in the bottle4. Also, it causes the purification function not to deteriorate that the temperature of the circulating drinking water6is prevented from falling resulting from the convection between the heated drinking water6and the drinking water6in the bottle4. Also, the drinking water6can be prevented from leaking resulting from erroneous operation at the water outlet36due to expansion or compression of the air in the bottle4because the heat of the heated drinking water6is not transmitted to the bottle4.

Second Embodiment

A second embodiment is an example of a variation of the valve38for controlling the supply of the drinking water6from the bottle4to the cold water tank8. This embodiment depicts a case of using a ball tap system.

This second embodiment will be described with reference toFIGS. 16,17A and17B.FIG. 16depicts an example of a structure of the valve according to the second embodiment, andFIGS. 17A and 178depict opened and closed states of the valve. Each of the structures depicted inFIGS. 16,17A and17B is an example.

This valve38is an inflow control means for the drinking water6from the water outlet36to the cold water tank8. The valve38is also an example of the above described convection suppressing means, and provides a float part210and an open and close unit212. This valve38is opened and closed according to the level of the drinking water6in the cold water tank8as well as the above embodiment.

The float part210is an example of a control means for opening and closing the water outlet36with rising and falling according to the level of the drinking water6in the cold water tank8. For example, an shaft214is provided for the top side of this float part210as depicted inFIG. 16. This shaft214is fitted into an shaft receiver216that is formed at one end of the open and close unit212.

The open and close unit212forms part of the valve38for opening and closing the water outlet36. The open and close unit212provides the above described packing96for its top side, which the water outlet36touches. One end of this open and close unit212is rotatably held by a fixing pin220in a fixing furniture218that is formed on the cover22. Another end of the open and close unit212provides the shaft receiver216as described above, and is fitted into the shaft214of the float part210to hold the shaft214rotatably.

In such a structure, when the float part210rises according to the rise of the water level in the cold water tank8as depicted inFIGS. 17A and 17B, the shaft receiver216of the open and close unit212pivots on the fixed pin220to move upward. The upward movement of the shaft receiver216makes the packing96adhere to the water outlet36, and stops supply of the drinking water6(FIG. 17A).

Fall of the water level in the cold water tank8makes the float part210and the shaft214fall. As well as the above, downward pivoting movement of the shaft receiver216of the open and close unit212releases the adhesion of the packing96to the water outlet36(FIG. 17B). Thereby, the air entering the cold water tank8from the air intake102blows from the water outlet36to the bottle4, Thus, the drinking water6in the bottle4drips into the cold water tank8.

The other structures or processing contents etc. of the drinking water dispenser2are the same as the above described embodiment, and thus the description thereof is omitted.

According to such a structure, as described above, an air layer is formed between the drinking water6in the cold tank8and the water outlet36. Thus, the drinking water and its heat can be prevented from convecting. For example, in the normal driving, the temperature of the drinking water6in the cold tank8can be prevented from rising. Also, in the purification process, the drinking water6in the bottle4can be prevented from being heated.

Third Embodiment

A third embodiment is an example of a variation of the valve38for controlling the supply of the drinking water from the bottle4to the cold water tank8. This embodiment depicts a case of using a float ball.

This third embodiment will be described with reference toFIGS. 18A and 18B.FIGS. 18A and 18Bdepict an example of a structure of the valve and its opened and closed states according to the third embodiment. Each structure depicted inFIGS. 18A and 18Bis an example.

This valve38consists of a float ball230that rises and falls according to the water level of the cold water tank8, and a float cover232that is placed on the cover22. The float ball230is an integrated composition of the above described float part94and packing96, for example. The float ball230rises or falls in the float cover232.

If the water level in the cold water tank8rises, the float ball230rises. If the float ball230reaches a predetermined water level, its upper surface adheres to the water outlet36. Thereby, the supply of the drinking water6is stopped (FIG. 18A). A packing234may be provided for the inside of this water outlet36in order to achieve better adhesion to the float ball230.

If the water level of the cold water tank8falls, the float ball230falls, and the water outlet36is released to supply the drinking water6(FIG. 18B). In this time, the float ball230may be held by the float cover232in order that its rising position is prevented from shifting.

The other structure or processing contents etc. of the drinking water dispenser2are the same as the above embodiments, and thus the description thereof is omitted.

Fourth Embodiment

A fourth embodiment depicts a case of using a switching valve240that consists of a solenoid valve or the like as the valve38that opens and closes the water outlet36.

This fourth embodiment will be described with reference toFIG. 19.FIG. 19depicts an example of a structure of the valve according to the fourth embodiment. The structure depicted inFIG. 19is an example. The other structure or processing contents, etc. of the drinking water dispenser2are the same as the above embodiments, and thus the description thereof is omitted.

As described above, this valve38is an inflow control means for the drinking water6from the water outlet36to the cold water tank8, and is also an example of a convection suppressing means. The valve38is formed by the switching valve240such as a solenoid valve, and performs its open and close control according to the water level in the cold water tank. This valve38includes the switching valve240and a water level detector242, for example.

The switching valve240is an example of a means for opening and closing the water outlet36. For example, open and close are switched by a solenoid valve or the like, For example, a valve disc244is placed inside the projection86that is a drinking water intake means. Driving instructions from the control device72is outputted to a drive unit246that consists of a solenoid and a motor, for example, to open and close the valve disc244.

The water level detector242is an example of a means for detecting the level of the drinking water6in the cold water tank8. For example, the water level detector242is attached to the cover22and the bottom of the cold water tank8. An electrode248that is energized when a predetermined water level is reached is placed on the cover22. A common electrode250of the water level detector242is also placed on the bottom of the cold water tank8. If it is detected that a predetermined water level is reached, this result is informed to the control device72.

If the water level detector242is OFF (water level is not reached), the switching valve240is into an opened state to supply water. If the water level of the cold water tank8rises and the water level detector242is turned ON, the switching valve240is into a closed state to cut off water.

Features are listed as follows concerning the above described embodiments.

(1) The drinking water dispenser of the present invention cools or heats the drinking water6that is supplied by the bottle4. Thus, the cooled drinking water6and the heated drinking water can be dispensed by a single device.

(2) Concerning the purification process of the drinking water dispenser2that cools and heats the drinking water6, the purification of the drinking water6can be efficiently performed with a simple structure using the drinking water6of heated hot water. It is also possible not to mix the heated drinking water6in the cold water tank8and the drinking water6in the bottle4.

(3) The drinking water dispenser2where the bottle4is placed and which cools the drinking water6supplied from the bottle4to provide cold water or heats the drinking water6to provide hot water includes the cold water tank8that is a first tank, a cooling means, a separating plate, a hot water tank10that is a second tank, a heating means, a water supply pipe, a cold water detector20that is a first temperature detecting means, a hot water detector60that is a second temperature detecting means, a by-pass pipe, a convection suppressing means and a control means. The first tank stores drinking water supplied from the bottle. The cooling means cools the drinking water in the first tank. The separating plate18is placed in the first tank to separate the drinking water in the first tank into an upper layer and a lower layer. The second tank is arranged below the first tank to store the drinking water6supplied from the bottle4. The heating means heats the drinking water6in the second tank. The water supply pipe12has an opening in the upper face of the separating plate, is inserted into the second tank, and supplies the drinking water that drips from the water outlet36to the separating plate, into the second tank. The first temperature detecting means detects the temperature of the drinking water6in the first tank. The second temperature detecting means detects the temperature of the drinking water6in the second tank. The by-pass pipe16is placed between the first tank and the second tank, and provides an open and close valve. The convection suppressing means opens and closes the water outlet36according to the water level of the first (cold water) tank, and suppresses convection of the cold or hot water to the bottle. The control means stops the cooling means in the purification process, operates the heating means, opens the open and close valve, and controls the temperature of hot water, which circulates in the first and second tanks via the by-pass pipe and the water supply pipe, under a predetermined temperature or over to circulate the hot water in a direction from the second (hot water) tank to the first (cold water) tank.

(4) The convection suppressing means is a float, and moves upward and downward according to the water level of the first tank. If the water level rises, the float is held at the water outlet36to shut the water outlet36using the surface tension of water and buoyancy that operates on the float as retention. An air layer is formed between the water outlet36and the water surface of the first tank of the full water level. This air layer separates water in the water outlet36and water in the first tank to prevent thermal convection between the first tank and the bottle.

(5) The convection suppressing means is a ball tap that moves upward and downward according to the water level of the first tank, and that opens and closes the water outlet.

(6) The convection suppressing means is an open and close valve. The convection suppressing means is structured so that the water level of the cold water tank is detected by the water level detector; and the open and close valve is opened if the water level detector is OFF, and is closed if the water level of the first tank rises and the water level detector is turned ON,

(7) The purification of the drinking water can be performed using the drinking water of hot water as high-temperature water with heating the drinking water of hot water.

(8) Concerning the drinking water dispenser that dispenses cold water or hot water, convection between cold water and the bottle can be suppressed, and the inconvenience such that cold water in the cold water tank or high-temperature water in the purification is mixed into water in the bottle can be prevented.

(9) In the purification, the inside of the cold water tank is heated by the drinking water heated in the hot water tank. Since thermal transmission to the drinking tank can be surely blocked even if remaining air expands or is compressed, leaking water due to erroneous operation can be prevented.

(10) An air layer can be formed in the cold water tank with block of the water outlet with the separator, to suppress thermal transmission or heating by hot water. Because a passage to the drinking tank is blocked, the air can be discharged or absorbed through the air intake.

(11) The temperature of the drinking water6in the cold water tank8can be maintained proper to the purification with a simple structure. If a necessary temperature is not reached even if predetermined time has passed, it is informed that there is an anomaly in the process of the purification. Thus, a sufficient purification process can be performed.

(12) A disconnecting device (separator float14having buoyancy) is provided. The drinking water6is supplied to the cold water tank8, and the separator float14rises as the water level in the cold water tank8rises to block the water outlet36that is a supply part. Thereby, it is ultimately suppressed to raise the water temperature in the bottle4and to expand an air layer due to thermal convection that influences even the bottle4when the inside of the cold water tank8is heated through high-temperature circulation.

(13) According to the above structure, a driving device such as a pump is not needed for high-temperature water circulation, and a complex control circuit can be prevented. Generating driving noise and much electricity consumption can be also prevented. Thermal influence on a gallon bottle at the same time when the inside of the cold water tank is heated can also be prevented in high-temperature circulation.

(14) There is a problem that the separator float14does not fall due to the surface tension although the water level in the cold water tank8falls. Enlarging the shape of the float makes its weight heavier, which can ensure the fall of the float.

(15) A high-temperature circulation function can be more efficient using for the air intake unit100of the bottle4, the small mesh filter106, such as a membrane filter, through which dusts in the air cannot pass.

Other Embodiment

(1) In the above embodiments, the separator float14falls according to the fall of the level of the drinking water6stored in the cold water tank8, and, for example, when touching the separating plate18, the separator float14is regarded as falling to the lowest position. The invention is not limited to this. For example, as depicted inFIG. 20, legs260may be provided for the bottom of the float part94. If the separator float14falls at a predetermined water level, these legs260touches the separating plate18. Thereby, for example, if the separator float14falls, it can be prevented that the opening32that introduces the drinking water6to the hot water tank10is shut, and the supply of the drinking water6is not to be interrupted.

Following effects can be obtained according to the drinking water dispenser of the present disclosure.

(1) Drinking water in the cold water tank, and drinking water of high-temperature in the purification and heat thereof are not convected to the bottle so that no temperature change is generated in drinking water stored in the bottle.

(2) The temperature of drinking water circulating in the purification process is prevented from lowering by convection between heated drinking water and drinking water in the bottle. Thus, a purification function for drinking water cannot deteriorate.

(3) Heat of heated drinking water is not transmitted to the bottle. Thus, it can be prevented that drinking water leaks due to erroneous operation at the water outlet by the expansion or compression of the air in the bottle.

The drinking water dispenser of the present disclosure has been described above. The above description is not intended to limit the present invention. It is apparent that various modifications or alterations may be made by those who skilled in art, based on the substance that is described in claims or disclosed in Detailed Description of the Invention. It is also obvious that such modifications or alterations are included in the scope of the present invention.

The drinking water dispenser of the present disclosure prevents the temperature of drinking water in a bottle from changing by controlling the supply of the drinking water from the bottle according to the level of the stored drinking water and by providing a valve that forms an air layer between drinking water in the tank and drinking water in the bottle. Also, the device can prevent the temperature of circulating drinking water in the purification process from lowering. Thus, the device is useful because not making the purification function of drinking water deteriorate, etc.