JPS62420B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a plurality of refrigerated and refrigerated cases installed in, for example, convenience stores, vending machines for cold food sales, and in-store air conditioners (hereinafter, each of these devices will be collectively referred to as "cooling equipment"). '') is a system that comprehensively performs energy-saving efforts to improve the power demand rate and reduce power consumption for a group of cooling equipment that receives power from the same indoor power source. The present invention relates to a control method and device for take-cycle operation.

Conventionally, when operating a group of cooling equipment installed in the same building or the same store by supplying power from the same indoor power source, it is possible to increase the power demand rate by saving power consumption and suppressing peak loads. For this purpose, a duty cycle operation method is often adopted in which each device alternately repeats an operation period and an operation stop period at fixed intervals such that power supply is stopped at staggered times. This duty cycle operation is performed with priority over the operation control by the thermostat attached to each cooling device. On the other hand, in carrying out the above-described duty cycle operation, it is necessary to regulate the operation stop time of each cooling device according to its heat load situation. That is, in an air conditioner, even if there is a slight change in the length of the shutdown time for each cycle of the duty cycle, the room temperature felt by the body will only change slightly and will not have much of an effect. However, depending on the type of refrigerated food, if the operation is stopped for a long time, the temperature of the product will rise significantly, which may reduce the quality and damage the product value. It is necessary to determine the operation stop time by calculation according to the conditions.

By the way, in order to centrally control the duty cycle operation described above for a group of cooling equipment that receives power from the same indoor power supply in the same place, it is necessary to install a duty cycle operation control panel installed in one place. Generally, a method is adopted in which operation commands are given to each device. Such an operation control panel constitutes a control circuit including a timer for setting a duty cycle period for each device and a timer for individually setting an operation stop time for each device. However, in the conventional duty cycle operation method, the cycle is set to a constant value, and based on this cycle, the operation stop time of each device is set to an appropriate value that suits the heat load condition. . This scheme will be explained with reference to FIGS. 1a and b. In each figure, represents each cooling device that receives power from the same power source. Further, T indicates the period of the duty cycle, and t and t' indicate the operation stop time. Figure a shows the duty cycle operation in the summer season when the ambient outside temperature is high, and Figure b shows the duty cycle operation in the winter season. The period T in the figure is set by the period setting timer in the control panel described above, whereas the operation stop times t and t' are set individually by the operation stop time setting timer for each device.
As is clear from this figure, in the conventional method, the period T is set to a constant value regardless of the season, that is, changes in the ambient outside temperature. The operation stop time t is individually set for each. If we were to apply this to the winter season when the ambient outside temperature is low without changing each setting value in Figure a, the heat load on the cooling equipment would decrease as the ambient outside temperature decreases, resulting in excessive cold storage operation. As a result, the original purpose of the duty cycle operation system, which is energy saving, cannot be fully achieved. For this reason, as shown in Fig. 1b, in the past, the cycle T was kept constant and the operation stop time t' was set longer than the summer setting value t for each device to save energy while maintaining an appropriate cold storage operation state. Duty cycle operation control is performed to enhance the effectiveness of the system.

However, with the above conventional method, it is necessary to individually adjust the operation stop time for each device in response to fluctuations in the ambient outside temperature such as seasonal differences, especially when there are a large number of cooling devices. Not only is this an extremely tedious task, but if a setting error is made, the quality of the products refrigerated in the store case may rise as the temperature rises, making it difficult for store managers who are not technical experts to do so. There were problems with operability, such as difficulty in setting the appropriate time.

The present invention solves the above-mentioned difficulties in operability in the conventional method, and allows the duty cycle operation settings to be easily changed in response to changes in ambient temperature, and there is no fear of setting errors even for non-experts. The object of the present invention is to obtain a duty cycle operation control method and device that can appropriately perform the duty cycle operation.

Next, the control method and device of the present invention for achieving the above object will be described in detail based on examples.

First, the principle of the duty cycle operation control method according to the present invention will be explained with reference to FIG. Figure 2 shows a case where the duty cycle operation is performed under the same setting conditions as in Figure 1a, but the settings are changed to suit the winter season when the ambient outside temperature drops, which is clear from the figure. In this way, only the period of the duty cycle that commonly regulates each device is changed from T to T' without changing the initial setting value of the operation stop time t. Further, the setting of the duty cycle period can be changed for one timer that sets the duty cycle period of all cooling devices, regardless of the number of cooling devices.
Moreover, according to this operation control method, each device ~
The operation stop time t for each cycle, which is initially set to an appropriate value according to the heat load conditions, does not change. Therefore, in freezing and refrigerated cases, the quality of refrigerated products can be maintained, and the overall operating cycle Duty cycle operation can be controlled under optimal conditions that match the ambient outside temperature, and the energy saving effect can be fully demonstrated.

Next, a control device of the present invention for carrying out the above-described control method will be explained with reference to FIGS. 3 to 5.

First, FIG. 3 shows an example in which eight cooling devices are collectively operated in a duty cycle, and in the figure, M ₁ to _{M 8} indicate each device connected to the same power supply circuit. The control device according to the present invention includes an adjustable timer T _A for setting the duty cycle;
Timers T ₁ to _{T 8} for initially setting the operation stop time for each device M ₁ to M ₈ , an auxiliary timer T _B for duty cycle timing, an auxiliary relay X _A , and each timer The relay contacts are used as circuit components to form a sequence circuit as shown in the figure. Also, among this sequence circuit,
In particular, the auxiliary relay X _A , each of the timers T ₁ to _{T 8} , and each of the auxiliary contacts constitute a sequential operation control circuit for sequentially operating the devices M ₁ to _{M 8} for a limited time. Furthermore, the power supply circuits of each device M ₁ to _{M 8} are individually equipped with auxiliary relays X _A and b operated by operation signals of timers T ₁ to _{T 7} .
Contacts X _{A ′} , T _{1 ′} to _{T 7 ′} are inserted, and while these contacts While it is there, the operation will be stopped.

Next, the operation of the duty cycle operation based on the sequence circuit shown in FIG. 3 will be described. For convenience of explanation, each contact of the sequence circuit in FIG. 3 is numbered 1 to 15 from the left, and the closing operation of each contact is indicated as ON, and the opening operation of each contact is indicated as OFF. First, when the power is turned on, the auxiliary relay X _A instantaneously operates through the contact 3, turns on the contact 5 to maintain self-holding, and turns on the contact 6 to start the time-limited operation of the timer _T1 . In addition, auxiliary timer T _B is energized through contact 2 and starts operating, and due to its time _- limited operation, contact ₁ is turned ON with a slight delay from the operation of relay Turn off. Thus, the auxiliary relay X _A is self-held by contacts 4 and 5, and this state continues until timer T ₁ operates. Further, while the auxiliary relay X _A is energized, the contact X _A ' is turned OFF, and the device M ₁ is in a stopped state. Next, when the predetermined set time elapses and timer _T1 operates, contacts 7 and 8
While self-holding through, contact 4 is turned OFF.
Then, release the auxiliary time relay _XA , turn on the contact 9, and start the time limit operation of timer _T2 . That is, the contact X _A ' returns to operation and starts operating the device M ₁ , and at the same time, the contact T ₁ ' is turned OFF to stop the operation of the device M ₂ . Thereafter, the timers T ₂ , . . . , T ₈ are shifted in the same manner so that they operate sequentially. On the other hand, when the periodic timer T _A operates after the predetermined time limit has elapsed,
Turn contact 2 OFF to reset auxiliary timer T _B. This operation turns off contact 1, resets the periodic timer T _A , and turns on contact 2 again to start the next cycle. FIG. 5 shows the above operations organized and expressed in a time chart. Note that T' and t in the figure indicate the period of the duty cycle and the operation stop time described in FIG. 2, respectively. As is clear from this time chart, each device M ₁ to _{M 8} in the cooling device group has a period
Duty cycle operation is performed in which operation and stop are repeated with T' as one cycle. Moreover, due to the sequential operation method of each timer _T1 to _T8 , the operation stop periods of each device are staggered in time, so that the power consumption of the entire cooling device group is skillfully equalized over time. It is possible to improve the power demand rate without creating a peak load.

On the other hand, in order to change the period of the duty cycle as shown in Figure 2 in response to changes in the ambient temperature such as seasonal changes, the time limit of the periodic timer T _A is adjusted in accordance with the ambient temperature. This is done by That is, by changing the time limit setting value of the period timer T _A , the period T' of the duty cycle shown in FIG. 5 changes, and the period is adjusted at the same rate for each device M ₁ to _{T 8} . Ru. Moreover, this cycle adjustment requires only one adjustment operation regardless of the number of cooling devices M ₁ to _{M 8} , and the initial period of timers T ₁ to T ₈ that individually set the operation stop time of each device M ₁ to _{M 8} is required. There is no need to change any settings. In addition, in order to operate the time limit setting of the periodic timer T _A in accordance with the ambient outside temperature, the time limit adjustment knob 1 of the periodic timer T _A , which is an adjustable timer as shown in Fig. 4 a and b, is required.
6 is a scale plate 17 that displays the outside temperature or season.
By arranging them facing each other, the duty cycle period can be adjusted extremely easily in accordance with fluctuations in outside temperature. Furthermore, periodic timer T _A
By connecting a temperature sensor that detects the outside temperature to the controller, the duty cycle operation can be automatically controlled in accordance with the surrounding outside temperature. If this automatic control were to be applied to the conventional method, the operation stop time for each device would be calculated individually in response to changes in the ambient outside temperature, and each timer T ₁
~ T ₈ settings must be changed, which complicates the hardware of the control device, but according to the method of the present invention, only the periodic timer T _A needs to be adjusted, which simplifies the hardware and software accordingly. It is advantageous because it can be converted into

As is already clear from the above description, according to the present invention, the duty cycle can be adjusted in just one place, regardless of the number of cooling devices, compared to the conventional method. It can be easily done by adjusting. Therefore, even a store manager who is not a technical expert can easily handle it and improve its operability.Furthermore, since there is no need to adjust or change the stoppage time, which is initially set to an appropriate value for each device, it is possible to It is possible to provide a duty cycle operation control method and device that have high practical value, such as being advantageous in terms of maintaining product quality for refrigerated storage cases and the like.

[Brief explanation of the drawing]

Figures 1a and b are time charts of duty cycle operation in summer and winter seasons to explain the conventional method, and Figure 2 is a duty cycle operation method based on the present invention corresponding to Figure 1b. 3 is a sequence circuit diagram of an embodiment of the duty cycle operation control device based on the present invention, and 4.
Figures a and b are configuration diagrams showing different embodiments of the periodic timer adjustment knob in Figure 3, and Figure 5 is a block diagram showing different embodiments of the periodic timer adjustment knob in Figure 3.
3 is a time chart showing the operation of the sequence circuit shown in the figure. T _A ...Timer for setting the duty cycle, T ₁ - _{T 8} ... Timer for setting the operation stop time for each cooling device, M ₁ - _{M 8} ... Cooling device, X _A ... Auxiliary relay, T _B ... Auxiliary Timer, T, T'...period of duty cycle, t, t'...operation stop time, 16...period timer time adjustment knob, 17...scale plate.

Claims (1)

[Scope of Claims] 1. For a group of cooling devices that are operated by receiving power from the same power source, by alternately repeating operation and stopping of each device at fixed intervals, the duty cycle of the group of cooling devices is integrated. When operating, the operation stop time for each cycle is set in advance, and each device is initialized to a predetermined value that is suitable for its heat load.
In addition to sequentially staggering the operation stoppage of each device, the initial setting value of the operation stoppage time is not changed, and only the period setting value of the common duty cycle for the entire cooling equipment group is set using the period setting timer. A duty cycle operation control method for a group of cooling equipment, characterized in that the duty cycle operation is changed and adapted to the ambient outside temperature. 2 One adjustable timer for setting the duty cycle of a group of cooling equipment that receives power from the same power source, and a timer that is individually adapted to the heat load for each equipment. A timer for initially setting the operation stop time, and a corresponding cooling device that sequentially operates each timer for setting the operation stop time for each cycle of the duty cycle defined by the time limit operation of the period setting timer. The circuit is configured with a sequential operation control circuit that stops the equipment, and the duty cycle of each equipment is adjusted at the same rate by changing the time limit of the timer for setting the duty cycle according to the ambient temperature. A duty cycle operation control device for a cooling equipment group, characterized in that the cycle period can be changed. 3. In the duty cycle operation control device according to claim 2, the duty cycle period setting timer is provided with a time adjustment knob with a scale plate displaying the ambient outside temperature or season. A duty cycle operation control device for a cooling equipment group, characterized by: 4. In the duty cycle operation control device according to claim 2, the duty cycle cycle setting timer is configured to automatically adjust the time limit of the timer according to the ambient outside temperature. A duty cycle operation control device for a cooling equipment group, characterized in that temperature sensors for detection are connected in series.