JPS6033458B2 - Tea manufacturing method - Google Patents

Description

[Detailed description of the invention] The present invention relates to a novel tea processing method.

Specifically, the heating mechanism that regulates the temperature of the hot air sent into the drying room is controlled using both the tea temperature and the tea temperature change rate, so that the tea temperature can be maintained more constant and the top drying process can be improved. To provide a new tea manufacturing and roughening method which enables drying to be carried out as constant as possible without drying, and to produce rough tea with excellent color luster, aroma, light blue color, etc. The temperature and volume of hot air sent into the drying room,
In the tea processing method, in which each control element in the tea processing process, such as the rotational speed of the main shaft on which the twilling hand and rear hand are attached, is changed sequentially as the process progresses, the first roughening process is completed. The control of the heating mechanism that stipulates this was done by setting several target values for the hot air temperature itself based on the experience and intuition of the operator, but with this method, large fluctuations in tea temperature were unavoidable. . For this reason, recent attempts have been made to directly detect the tea temperature itself and control the heating mechanism using the tea temperature as an index, or to go further, to control the heating mechanism from the mutual relationship between the absolute humidity in the drying room and the tea temperature. An invention that attempts to
Japanese Unexamined Patent Publication No. 55-162941) etc. have been made.

However, even with these methods, fluctuations of around 4°C in tea temperature cannot be avoided. This was caused by a delay in the response of the tea temperature to the control of the heating mechanism.
The present invention has been made in view of the above circumstances, and by using the tea temperature change rate as well as the tea temperature change rate as an index for controlling the heating mechanism, it is possible to perform fine control by anticipating the tea temperature response delay in advance. , by keeping the tea temperature more constant and drying as constant as possible without over-drying.
This makes it possible to produce rough tea with excellent color, aroma, and light blue color.

The present invention will be described in detail below, but first, an example of a tea processing machine suitable for carrying out the present invention will be described.

FIG. 1 schematically shows a tea processing machine 1. As shown in FIG.

2 is a hot air generator attached to this tea processing machine 1.

Reference numeral 3 denotes a frame of a tea processing machine, and the frame 3 has a shaft 4 and a main shaft drive section 5 mounted thereon. The Sogetsu Do 4 has a gutter-like shape with both ends closed, and a take-out door 6 that can be opened and closed is formed at the lower part of the front side to take out the tea leaves after roasting. A main shaft 7 is rotatably provided in the Hainzukioka 4, passing through it in the axial direction and being rotated by the drive unit 5. 9,9・
... is attached. Reference numeral 10 denotes an oak scattering chamber made of lotus grains at the upper end of the steering drum 4, a window 11 that can be opened and closed is provided at the front, and a hot air blowing row 2 is provided at the rear.

Reference numeral 13 denotes a steamed leaf pool placed at the upper end exhaust port of the diffusion chamber 10. Tea leaves are put into this pool until it reaches a predetermined weight, and when the lower door (not shown) is opened, the contents of the pool 13 are Tea leaves are put into a drying chamber consisting of a drying chamber 4 and a fly scattering chamber 10.

Note that this steamed leaf pool 13 is usually equipped with a tea leaf weight measuring device. Reference numeral 14 denotes a wire mesh that covers the upper end exhaust port of the fly dispersal chamber 10.

15 is a tea temperature sensor provided at the bottom of the teacup 4; 16 is a tea temperature setting dial for setting a target tea temperature; and 17 is a control panel incorporating various circuits for control as described below.

Reference numeral 18 denotes a hot air guide formed on the rear side of the scattering room 10, and one end of which is connected to the hot air outlet 19 of the hot air generator 2.

The hot air generator 2 includes a heat exchange section 20 and an air supply fan 21.

The heat exchange section 20 includes a furnace cylinder 23 and hot air passages 24, 24, . The hot air generated in the furnace tube 23 by the burner 25 is discharged from the chimney 26 through hot air passages arranged in a labyrinth in the casing 22. The burner 25 supplies fuel to the furnace cylinder 2.
A fan 27 for generating airflow to atomize the fuel into the engine 3, an ignition transformer 28 for generating sparks, and an oil pump 29 for pressurizing the fuel are attached.

Although not shown, the burner 25 is provided with two nozzles that generate different amounts of heat, and electromagnetic valves 30 and 31 (not shown) are provided in the middle of the piping to each nozzle. Switching between high combustion and low combustion can be achieved by operating the solenoid valve in three ways: opening and closing the two nozzles, igniting one, and igniting the other. It has become. Air is air supply fan 2
1 directly from the outside or through a suitable filter, enters the casing 22 through the air inlet 32 that passes between the air fan 21 and the kerating 22, and enters the air guide 18 through the hot air outlet 19. supplied to

When the air passes through the casing 22, it comes into contact with the heated surfaces of the furnace tube 23 and the hot air passages 24, 24, . . . and is heated to become hot air. Then, this hot air is supplied into the drying chamber from the hot air blowing ports 12, 12, . . . through the hot air guide 18. In addition, the air supply fan 21 and the air supply □
Although not shown, a damper for adjusting the amount of hot air whose opening/closing degree is controlled by the control motor 33 is disposed between the hot air flow rate control member 32 and the control motor 33 . A potentiometer 34 detects the amount of hot air being sent into the drying chamber based on the rotational position of the control motor 33.

In the tea manufacturing process, the tea leaves steamed in the previous process are dried using the tea processing machine as described above until the residual moisture content is reduced to approximately 50%. It does not mean that it is good, but it must be done in a way that does not deteriorate the quality of the tea leaves, such as their color, aroma, and light blue color.

To do this, each control element in the tea processing process, such as the temperature of the hot air sent into the drying chamber during the tea processing process 1, the amount of hot air, and the rotation speed of the main shaft, is changed sequentially as the process progresses. . For example, the amount of hot air sent into the drying chamber is controlled by adjusting the opening/closing degree of a damper disposed between the air blowing fan 21 and the air blowing □ 32 of the heat exchange section 20.

Further, the temperature of the hot air sent into the drying chamber is controlled by adjusting the burn-up of the burner 25.

In this case, a temperature sensor is placed at an appropriate location in the hot air guide 18, and at the beginning of the process, the temperature of the hot air blown into the drying chamber is detected. During the process, the tea overflow sensor 15 detects the tea temperature of the tea leaves that are currently soaked in the drying chamber, and compares this value with the target tea temperature and target tea temperature change rate. A mode of controlling the burnup of
A possible method is to detect the tea temperature from the beginning of the process and compare this value with the target tea temperature or target tea temperature change rate to control the heat competition of the burner. FIG. 2 is a block diagram of the control section, and FIG. 3 is a flowchart showing the procedure for implementing the present invention.

In FIG. 2, the CPU is a central processing unit that performs various calculations and processes necessary to execute the method of the present invention.

EPROM is an erasable and writable dedicated memory that is connected to the CPU, and stores calculations performed by the CPU, various processing procedures, pre-existing patterns that serve as indicators of the transition of various control elements, target tea temperature change rate, etc. . RAM is a random access memory connected to the CPU that stores data necessary for the CPU to perform calculations and processing, such as dial 16.
The target tea temperature, the current tea temperature detected by the tea temperature sensor 15, the current amount of hot air, etc. are temporarily stored. A
/D is an analog-to-digital converter. 35 is CPU
36 is a gate/latch control circuit.

The tea temperature sensor 15, the tea temperature setting dial 16, and the potentiometer 34 are connected to the input/output boat 3 via an analog/digital converter and through respective gate circuits 37 that are opened and closed by signals from a gate/latch control circuit 36.
5. Including fan 27 of burner 25, ignition transformer 28, oil pump 29, solenoid valve 30
The solenoid valve 31 is connected to the burner control relays 38, 39 and the gate.
a latch circuit 40 controlled by a latch control circuit 36;
It is connected to the input/output boat 35 via 40. still,
A configuration in which a temperature sensor is placed at an appropriate location in the hot air guide 18 to detect the temperature of the hot air blown into the drying chamber, and the burn-up of the burner is controlled based on the difference between this value and the target value at that time. Since this is conventionally known and is not an essential part of the present invention, it will be omitted.

Therefore, the tea processing method of the present invention using the tea processing machine as described above is performed as follows, but the control of changes in control elements such as the hot air volume and the rotation speed of the main shaft is different from the conventional method. However, since this is not an important part of the present invention, the flow related to the control of the burner 25 will be described in detail here.

First, the amount of hot air currently being sent into the bare drying room is indirectly read by the potentiometer 34 attached to the control motor 33 that controls the opening/closing degree of the damper for adjusting the amount of hot air.

[A] Determine which of the air volume levels shown in Table 1 the current hot air volume falls under.

Table 1 This table 1 has been obtained empirically and varies depending on the capacity of the tea processing machine, the variety of raw tea leaves, the time of harvesting, etc. All of these values and their correspondence are stored in the EPROM. ing.

{U) Determine whether or not the relevant air volume range has changed from the air volume castle read last time. If "yes", that is, the relevant air volume castle has changed, proceed to the next step; if "no", proceed to the next step. .

C} Read the basic pattern of the heating cycle (high combustion x seconds, low combustion Y seconds) for the air volume castle from Table 1.

For example, if the hot air volume read is 86/min, the air volume is A and (X=10, Y=30) is read into the RAM.

Rules The tea temperature of the tea leaves currently being rubbed is read by the tea temperature sensor 15 provided at the bottom of the teacup barrel 4.

(Power) Read the target tea temperature set with the tea temperature setting dial 16. This target tea temperature is usually selected within the range of 34 to 3800. (G) Determine whether the value obtained by subtracting the current tea temperature from the target tea temperature is negative, and if the answer is "no", proceed to the next step; if the answer is "yes", proceed to (evening).

(h) High combustion x seconds to judge whether it has finished or not, and answer “no”
If so, proceed to the next step, and if “yes” proceed to (c).

(i) Output a high combustion command signal to burner control relays 38 and 39 and return to the enemy. In other words, turn on the fan 27 of the burner 25, the ignition transformer 28, and the oil pump 29, and return both the solenoid valves 30 and 31 to their original state.

(J) Determine whether Y seconds of low combustion have ended or not, and if "No", proceed to the next step; if "Yes", proceed to (C).

(S) Outputs a low combustion command signal to burner control relays 38 and 39 and returns to the sword. For example, the solenoid valve 30 outputs "31" to "Kaiichi" and then returns to Bo. In other words, the flow up to now was when the air volume was changed, and the tea temperature is currently the target. If the tea temperature is lower than the tea temperature, the first heating cycle is as shown in Table 1. In air volume area A, sand with high combustion level 1, low combustion level is 30 seconds, and in air volume area B, high combustion rate is 8 seconds, low combustion level is 30 seconds. The basic pattern is 32 seconds of combustion, 4 seconds of high combustion, and 3 competitive sands for low combustion in airflow castle C.

(C) Calculate the rate of change in tea temperature in 1 heating cycle (X+Y) seconds.

(S) Determine whether or not it is within the allowable error range of the daily standard tea temperature change rate stored in advance in the EPROM. If "no", proceed to the next step; if "yes", proceed to the next step. return.

In the case of this example, the target tea temperature change rate is 0.15°C/4 sand, and the allowable error range is 0.15°C/4 sand.

It should be noted that this value was also obtained empirically as in Table 1 above.

(C) Subtract the target tea temperature change rate from the tea overflow rate calculated in (C) to calculate the error.

(S) Read the correction value (△×, △Y) corresponding to the error from Table 2, correct (×, Y), change the high combustion/low combustion ratio, and return to the previous step.

Table 2 Table 2, like Table 1, was obtained empirically, and the EPR
Pre-stored in OM.

For example, when we performed a heating cycle of sand with high combustion level 1 and inkstone sand with low combustion level 3, the rate of change in tea temperature during that period was -0.130o.
/4 inkstone sand, the error from the target tea temperature change rate is (-0.1yo/4 sand) - (0.150o/4 inkstone sand)
= -0.2800/40 seconds, and from Table 2 (△X=
+9, △Y=-9), X=109, Y=
It is corrected to 30-9 and changed to a pattern of high combustion for 19 seconds and low combustion for 21 seconds. To explain this with reference to FIG. 4, sections 41 and 42 are the heating cycles before correction, sections 43 and 44 are the heating cycles after correction, and the high combustion section is 4.
1 of 1 sand to 43 of 1 spot, low heat firing section is 42 of 3
The heating cycle pattern has been changed from sand to 44 and 21 seconds. In other words, in the flow from (shi) to (so), if the current tea temperature is less than the target tea temperature, the rate of change in tea temperature in each heating cycle is calculated by repeating a heating cycle that alternately repeats high combustion and low combustion. It attempts to monitor and change the pattern of the next heating cycle.

(Evening) Determine which air volume level the current hot air volume corresponds to, and if it is A, proceed to the next step, and if it is B or C, proceed to (T).

(H) Output a low combustion command signal to burner control relays 38 and 39, and return to what. In other words, when the current tea temperature exceeds the target tea temperature, the burner enters a system in which low combustion is performed to lower the tea temperature.

The low combustion will continue until the tea temperature falls below the target tea temperature. To explain this with reference to Figure 4, which shows the relationship between the tea temperature and the burner combustion state at air volume castle A,
Section 45 corresponds to the time during which the above-mentioned low combustion is occurring.

Note that when the hot air volume corresponding to air flow rate A is being sent into the drying chamber, the tea leaves still have a considerable amount of moisture, so if the burner 25 is completely stopped, the tea temperature will drop rapidly. Therefore, they try to cause low combustion and gradually descend.

(t) Set the counter for 10 seconds and read the tea temperature at the time of setting.

Note that the sand counter 1 is a type of timer, and in this embodiment, it is configured as software, but the details will be omitted. (Te) Determine whether the 10 second counter has counted up or not. If "No", proceed to the next step; if "Yes", proceed to (Na).

(G) Output a post-purge command signal to burner control relays 38 and 39, and return to the next step.

In other words, while the fan 27 of the burner 26 is kept rotating,
Both the solenoid valves 30 and 31 are "closed" to forcefully exhaust the hot air inside the furnace tube 23, cool the furnace tube 23, and limit the amount of heat given to the tea leaves to a maximum of 4.5 mm, thereby preventing a rise in tea temperature. I'm trying to do that.

(na) Read the tea temperature when the 10 second counter counts up.

(d) Determine whether the value obtained by subtracting the tea temperature when counting up from the tea temperature when the counter is set for 10 seconds is 0, negative, or apricot, and if "No", proceed to the next step, and "Yes".
If so, proceed to (ne).

(NU) Reset the counter for 10 seconds and return to the enemy. (N) Output an operation stop command signal to the burner control relays 38 and 39 and return to the control.

In other words, when the current tea temperature exceeds the target tea temperature and the amount of hot air being sent into the drying room falls under the air volume range B or C, In the flow,
Repeat the post-purge for each sand until the tea temperature starts to drop, increasing the amount of heat given to a maximum of 4.5 cm to suppress the rise in tea temperature as soon as possible. When the tea temperature starts to drop, stop post-purging and then cool the tea. By sending in hot air heated by the residual heat of the furnace tube, the tea leaves are prevented from falling excessively.

To explain this with reference to Fig. 5, which shows the relationship between tea temperature and burner combustion state in air volume ranges B and C, section 46
corresponds to the time during which post-purging is repeatedly performed for each inkstone sand, and period 47 corresponds to the time during which the operation of the burner is completely stopped and heating is attempted only by the residual heat of the furnace cylinder.

Furthermore, when the amount of hot air corresponding to air volume B or C is being sent into the drying chamber, the tea leaves have already released a considerable amount of moisture, and the tea temperature will respond sensitively to the amount of heat supplied. Therefore, if the combustion continues at a low level, the tea temperature will rise further, and even if you suddenly stop the burner operation, the residual heat from the hot furnace cylinder will still cause it to rise.

Therefore, a post-purge is performed to cool the furnace tube and minimize the amount of heat given, but if the post-purge is continued until the tea temperature falls below the target tea temperature, the furnace tube will become too cold and the tea temperature will drop. In order to prevent the tea temperature from dropping excessively, the post purge is repeated every 10 seconds until the tea temperature starts to drop, and then hot air heated by the residual heat of the cooled furnace tube is sent in to prevent the tea temperature from dropping excessively. That's what I did. In addition, in the first invention, other embodiments in which the amount of fuel supplied to the heating mechanism is directly controlled may also be considered, but since it can be easily inferred from the above explanation, the details thereof will be omitted.

In the above embodiment, one target tea temperature was used as an index for controlling the heating mechanism, but next, another embodiment using two target tea temperatures, upper and lower, as indicators will be described.

First, when one target tea temperature is set using the tea temperature setting dial 16, a value lower than that value is automatically set. Then, the upper target tea temperature and the lower target tea temperature are written into the RAM.

Then, when the initial current tea temperature measured at the beginning is less than the lower target tea temperature, a flag is set, otherwise the flag is not set, and thereafter, the current tea temperature is lower than the lower target tea temperature. A flag is set when the upper target tea temperature is exceeded, and the flag is turned off when the upper target tea temperature is exceeded.When the flag is set, the lower target tea temperature is used as the indicator, and when the flag is not set, the upper target tea temperature is Configure the flow to serve as an indicator.

To explain this with reference to FIG. 6, if the initial current tea temperature is point 48, a flag is set and the lower target tea temperature becomes an index for controlling the heating mechanism.

If the initial current tea temperature is point 50 or 54, no flag is raised and the upper target tea overflow becomes the indicator. When the tea overflow starts at point 48, the current tea temperature is below the target tea temperature, so a heating cycle is performed in which high combustion and low combustion are repeated, and the tea temperature reaches point 49. At point 49, the flag remains on, so if the lower target value is exceeded, a cooling cycle such as low combustion or post-purge will be performed, and the tea temperature will drop through point 50 without exceeding the upper target value, and the tea temperature will drop to point 51. leading to. Since the flag remains set even at point 51, the heating cycle is restarted when the lower target tea temperature is exceeded. Thereafter, the tea temperature rises and exceeds the lower target tea temperature again at point 52, and the cooling cycle begins.

Then, when the tea temperature continues to rise and reaches point 53,
The flag that had been standing for a long time will be erased. but,
Even if the flag is cleared, the cooling cycle continues,
The tea temperature drops via point 54 and reaches point 55. Since the flag is not set at point 55, the upper target tea temperature is the control index, and the heating cycle is restarted from this point. Then, at point 56, the lower target tea temperature is lowered, so the flag is set again. By setting the target tea temperatures above and below and switching between them as appropriate, the delay in tea temperature response can be corrected in advance, and the tea overflow can be maintained even more constant.

As is clear from the above description, according to the tea manufacturing and roughing method of the present invention, the heating mechanism is controlled using both the target tea temperature and the target tea temperature change rate as indicators, thereby delaying the response of the tea temperature. By making it possible to correct this in advance, the tea temperature can be maintained extremely constant, and its changes are also very smooth, which in turn balances the rate of evaporation of moisture on the surface of the tea straw with the rate of transfer of moisture inside the tea leaves to the surface. It is possible to dry the tea at a constant rate and produce rough tea with excellent color, aroma, light blue color, etc.

[Brief explanation of drawings]

The drawings show an example of the implementation of the present invention, and FIG. 1 is a partially cutaway perspective view showing the entire rough probe, FIG. 2 is a block diagram of the main control section, FIG. 3 is a flowchart, and FIG.
Figure 5 shows the relationship between tea temperature and burner combustion status in a large air volume area, Figure 5 shows the relationship between tea temperature and burner combustion status in a small air volume area, and Figure 6 shows the relationship between tea temperature and burner combustion status in a small air volume area. FIG. 6 is a diagram for explaining switching of indicators when two indicators are set. 1... Tea processing machine, 2... Hot air generator, 4... Bare body, 7... Main shaft, 8...
...Manipulator, 9...Your hand, 10...Concentration chamber, 15...Tea overflow sensor, 16...Tea temperature setting dial, 21... ...Air fan, 23...
...Furnace tube, 25...Burner, 27...
... Fan, 33 ... Control motor, 34 ... Potentiometer, 35 ... Input/output boat, 36 ...
...Gate latch control circuit, 37...Gate circuit, 38, 39...Burner control relay, 40
...Latch circuit, RAM, EPROM...Memory, CPU...Central processing unit. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Scope of Claims] 1. Each control element in the tea manufacturing process, such as the temperature of hot air sent into the rolling drying chamber, the amount of hot air, and the rotation speed of the main shaft on which the rolling hands and dredges are attached, is controlled according to the progress of the process. In the tea manufacturing method in which the first rough rolling step is completed by sequentially changing the temperature of the tea, the heating mechanism that regulates the hot air temperature is controlled using both the tea temperature and the tea temperature change rate as indicators. Characteristic tea manufacturing method. 2. While changing each control element in the tea roughing process sequentially as the process progresses, such as the temperature of the hot air sent into the rolling and drying room, the amount of hot air, and the rotation speed of the main shaft on which the rolling hands and dredges are attached, In the tea manufacturing method that finishes the rough rolling process, the heating mechanism uses a so-called microcomputer with a microprocessor at its core to regulate the hot air temperature. When the tea temperature is below the target tea temperature, a cooling cycle is performed, and when the target tea temperature is below, a heating cycle is performed that alternately repeats high combustion and low combustion. A tea processing method characterized in that the ratio of high combustion and low combustion is controlled to be corrected according to the error. 3. The tea manufacturing and roughening method according to claim 2, wherein the cooling cycle is performed with low combustion. 4. The tea manufacturing and roughening method according to claim 2, wherein the cooling cycle is performed by stopping the operation of the heating mechanism after post-purging. 5 While changing each control element in the tea roughing process sequentially as the process progresses, such as the temperature of the hot air sent into the rolling and drying room, the amount of hot air, and the rotation speed of the main shaft on which the rolling hands and dredges are attached, In the tea manufacturing method that finishes the rough rolling process, the heating mechanism uses a so-called microcomputer with a microprocessor at its core to regulate the hot air temperature. When the tea temperature is over the target tea temperature and a large amount of hot air is being sent, the cooling cycle is performed with low combustion, and when the target tea temperature is exceeded and a small amount of hot air is being sent. After post-purging, the operation is stopped and a cooling cycle is performed, and when the target tea temperature is below the target tea temperature, a heating cycle is performed in which high combustion and low combustion are repeated alternately, and the rate of change in tea temperature and target tea are calculated for each heating cycle. A tea processing method characterized in that the ratio of high combustion and low combustion is controlled to be corrected according to the error with the rate of temperature change. 6. The tea manufacturing and roughening method according to claims 1 to 5, wherein the upper and lower temperatures are switched at appropriate times to reach a target tea temperature.