JP2672997B2 - Fixed quantity tapping device - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial application field) The present invention relates to a fixed-quantity tapping device used for an electric heating pot or the like.

(Prior Art) For example, when hot water is supplied to ground coffee beans to extract the coffee liquid, it is necessary to make the supplied amount of water constant in order to make the concentration of the coffee liquid constant. For this reason, for example, there is an electric heating pot equipped with a fixed-quantity hot-water supply device so that a fixed amount of hot water can be supplied by one operation.

That is, conventionally, as shown in FIG. 6, hot water 32 contained in a container 31 is sucked by a discharge pump 33 and discharged from a discharge pipe 34.

Then, as shown in FIG. 7, the timer circuit 36 is operated by turning on the hot water switch 35.
The pump drive circuit 37 is operated to operate the hot water discharge pump 33 for a fixed time.

(Problems to be solved by the invention) By the way, as shown in FIG. 8 (a), the hot water discharge pump 33 has variations in pump hot water discharge characteristics, and therefore there is a problem that the hot water discharge amount per unit time varies depending on the hot water discharge pump used. is there.

Further, since the cavitation generated in the hot water pump 33 changes depending on the hot water temperature, there is a problem that the hot water discharge amount decreases at a high temperature as shown in FIG. 8 (b).

Further, when the water level of the hot water in the container 31 is different, the pressure at the hot water outlet changes, so that there is a problem that the amount of hot water discharged changes depending on the water level, as shown in FIG. 8 (c).

However, in the conventional device, since the hot water discharge pump 33 is simply operated for a certain period of time, there is a problem that a fixed amount of hot water cannot be discharged accurately due to the change in the amount of hot water caused by the above-mentioned problems.

Therefore, the present invention is intended to provide a constant amount hot water discharge device capable of always accurately discharging a fixed amount of hot water.

[Means for Solving the Problems] (Means for Solving the Problems) The present invention relates to a hot water discharge means for sucking hot water in a container by an electric mechanism through a hot water discharge pipe and hot water at two points separated by a predetermined distance in the hot water discharge pipe. Detecting means for detecting the arrival of the hot water, a calculating means for calculating the operating time of the electric mechanism for quantitative hot water discharge from the difference in the arrival times of the hot water at the two points detected by the detecting means, and the operation calculated by the calculating means. An electric mechanism driving means for driving the electric mechanism only for time is provided.

(Operation) In the present invention having such a configuration, when the electric mechanism operates, the hot water in the container is discharged to the outside through the hot water pipe. Then, the operation time of the electric mechanism is calculated from the time difference between the hot water reaching the two points in the tapping pipe, and the electric mechanism is operated for the operation time.

That is, let the hot water discharge capacity of the electric mechanism be V _P
Assuming V _C , the operating time TA of the electric mechanism becomes TA = V _C / V _P (1). Here, if the internal volume between the two points A and B in the tapping pipe is V _AB and the above equation (1) is modified, TA = V _C / V _AB × V _AB / V _P (2)

Further, the time t for the hot water to reach the B point from the A point by the operation of the electric mechanism is t = V _AB / V _P (3). Substituting the equation (2) into the equation (3), TA = M × t (4) Here, since M is a constant determined by M = V _C / V _AB , it is necessary to count the time difference t during which the hot water arrives between the two points A and B to discharge the fixed amount of hot water V _C. The operating time TA of the electric mechanism will be required.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows the structure of an electric heat insulation pot. Reference numeral 1 is a housing, and 2 is a container housed in the housing 1. A heater 3 is provided on the lower outer surface of the container 2 to heat the water 4 in the container 2.

A hot water discharge port 5 is provided at the bottom of the container 2, a hot water discharge pipe 6 extends from the hot water discharge port 5, and a suction port of a hot water discharge pump 7 which is an electric mechanism is connected to the tip of the hot water discharge pipe 6. There is. One end of a hot water discharge pipe 8 is connected to the discharge port of the hot water discharge pump 7. The hot water outlet pipe 8 is made of a translucent material, and is placed from the bottom position of the container 2 to the container 2
It is erected so as to rise along the side surface of the housing 1, and the other end side is bent in an inverted U shape at the upper part of the housing 1 so that its tip faces downward to form a hot water supply port 9.

A translucent window 10 is provided on the upper side surface of the container 2 to display the full water position outside.

Above the standing portion of the hot water pipe 8, a detecting means 11 for detecting the arrival position of the hot water in the pipe is provided.

As shown in FIG. 2, the detecting means 11 has an optical sensor disposed between two points on the hot water outlet pipe 8 which are separated by a predetermined distance. At the lower point A, a light emitting element 12a and a light receiving element are provided as a first flow rate sensor. The element 12b is arranged to face each other with the hot water discharge pipe 8 interposed therebetween, and the light emitting element 13a and the light receiving element 13b as the second flow rate sensor are arranged to face each other with the hot water discharge pipe 8 interposed therebetween at the higher point B. .

A spherical float 14 is housed vertically between the points A and B of the tap pipe 8, and the lower stopper 15 is set so that the vertical movement range of the float 14 is exactly at points A and B. And the upper stopper 16 is attached.

Further, in FIG. 1, 17 is a hot water switch, 18 is a control box accommodating a control circuit, and 19 is a connector for connecting a power cord.

FIG. 3 shows a circuit configuration of a main part, and 20 is a microcomputer which constitutes the main body of the control part.

One ends of the light emitting element 12a and the light receiving element 12b are connected to a + power source, and the other ends are grounded via resistors 21 and 22, respectively. Further, one ends of the light emitting element 13a and the light receiving element 13b are connected to a + power source, and the other ends are grounded via resistors 23 and 24, respectively.

The connection point between the light receiving element 12b and the resistor 22 is connected to the input port IN ₁ of the microcomputer 20, and the connection point between the light receiving element 13b and the resistor 24 is connected to the input port IN ₂ of the microcomputer 20. And the outlet switch 17 is connected to the input port IN _{3 of the} microcomputer 20.
Connected to

A pump drive circuit 25 for driving and controlling the hot water discharge pump 7 is connected to the output port OUT ₁ of the microcomputer 20.

The microcomputer 20 is provided with a flow rate counter 26 and various flag memories 27 such as a hot water discharge SW flag and a TA flag.

The microcomputer 20 is programmed to perform the control shown in FIG. That is, when the hot water outlet switch 17 is operated when the hot water outlet SW flag = 0, the operation of the pump drive circuit 25 is controlled after the hot water outlet SW flag = 1. Then, it is checked whether or not the output of the first flow rate sensor has become H, that is, high level. This is to check whether the light receiving element 12b has received the light from the light emitting element 12a.

When the output of the first flow rate sensor becomes high level, the counting operation of the flow rate counter 26 is started. Then, it is checked whether or not the output of the second flow rate sensor has become L, that is, low level. This is because the light receiving element 13b is the light emitting element 13a.
You will check if you no longer receive the light from.

When the output of the second flow rate sensor becomes low level, the counting operation of the flow rate counter 26 is stopped.

Subsequently, it is checked whether the TA flag = 1. This checks whether or not the operating time of the hot water pump 7 has already been calculated. If TA flag = 0, TA = M (constant) × count value (t) of the flow rate counter is calculated to calculate the operating time TA of the hot water pump 7. Then, the TA flag is set to 1.

The calculated time TA is subtracted by the output of a clock circuit provided inside. When TA = 0, the TA flag and the hot water discharge SW flag are set to 0, and the operation of the pump drive circuit 25 is stopped.

In this embodiment having such a configuration, when the hot water discharge switch 17 is operated while hot water is contained in the container 2, the pump drive circuit 25 is operated and the hot water discharge pump 7 is started.
Then, the hot water in the container 2 is discharged into the hot water pipe 8 by the hot water pump 7.

When the hot water flows through the hot water outlet pipe 8, the float 14 which was originally at the point A is pushed up by the hot water. As a result, the light emitted from the light emitting element 12a shielded by the float 14 is received by the light receiving element 1
The light is received by 2b. In this way, the flow rate counter 26 starts the counting operation. Then, the float 14 eventually reaches the point B. This makes the light emitting element
The light from 13a is blocked by the float 14 and is not received by the light receiving element 13b. Thus, the counting operation of the flow rate counter 26 is stopped.

Thus, the time required for the hot water in the hot water outlet pipe 8 to reach the point B from the point A is counted by the flow rate counter 26.

Then, this count value t and a preset constant M
The operating time TA of the tap water pump 7 is calculated from {this is a constant determined by V _C (quantitative hot water discharge amount) / V _AB (internal volume of the pipe 8 between point A and point B)}, and only that time TA is calculated. Hot water pump 7 is operated.

In this way, a certain amount of hot water is supplied from the hot water supply port 9.

In this way, the operating time of the hot water discharge pump 7 is obtained from the difference in hot water arrival time between the two points A and B, so that when the hot water discharge amount per unit time is large, for example, As the flow rate increases, the count value t of the flow rate counter 26 decreases and the operating time of the hot water pump 7 decreases to T ₁ as shown in FIG. Further, when the amount of hot water discharged per unit time is small, the flow rate of the hot water flowing in the hot water discharge pipe 8 becomes small.
Becomes longer and the operation time of the hot water discharge pump 7 becomes longer as T ₃ as shown in FIG. When the amount of hot water discharged per unit time is medium, the count value t of the flow rate counter 26 is not so large and the operating time T ₂ of the hot water discharge pump 7 becomes T ₁ <T ₂ <T _{3 as} shown in FIG. .

That is, since the operating time of the hot water pump 7 is obtained from the difference in the hot water arrival time between the two points A and B, even if there are variations in the characteristics of the hot water pump 7, the temperature of the hot water in the container Even if the water or water changes, a fixed amount of hot water can always be discharged without being affected by them.

It should be noted that, in the above-described embodiment, the one in which the light from the light emitting element is shielded by the float is described as the detection means, but the invention is not necessarily limited to this. The arrival of hot water may be detected by utilizing the deviation of the optical axis.

[Effect of the Invention] As described above in detail, according to the present invention, the tapping pipe 2
By determining the operation time of the hot water discharge pump from the difference in the hot water arrival time between the points, it is possible to provide a constant quantity hot water discharge device that can always discharge a fixed quantity of hot water accurately.

[Brief description of the drawings]

1 to 5 show an embodiment of the present invention.
Fig. 2 is a block diagram of an electric heat-insulating pot, Fig. 2 is a partially enlarged view showing the structure of a detection unit for detecting the arrival of hot water, Fig. 3 is a circuit block diagram of essential parts, and Fig. 4 is the amount of hot water discharged per unit time. 5 is a graph showing the relationship with the operating time of the hot water discharge pump, FIG. 5 is a flow chart showing hot water discharge control by a microcomputer, FIGS. 6 to 8 are conventional examples, FIG. 6 is a schematic configuration diagram, and FIG. FIG. 8 is a block diagram of a main circuit, and FIG. 8 is a graph showing a hot water discharge amount characteristic due to various factors. 2 ... Container, 7 ... Hot water pump (electric mechanism), 8 ... Hot water pipe, 11 ... Detection means, 12a, 13a ... Light emitting element, 12
b, 13b: Light receiving element, 14: Float, 20: Microcomputer, 25: Pump drive circuit.

Claims (1)

(57) [Claims] 1. A hot water discharging means for drawing hot water in a container by an electric mechanism to discharge hot water through a hot water discharging pipe, a detecting means for detecting arrival of hot water at two points separated by a predetermined distance in the hot water discharging pipe, and this detecting means. Calculating means for calculating the operation time of the electric mechanism for quantitatively discharging hot water from the arrival time difference of the hot water at the two points detected by the electric mechanism drive for driving the electric mechanism for the operation time calculated by the calculating means. A fixed quantity hot water discharge device characterized by comprising means.