CN100404973C - freezer - Google Patents

提供一种冷冻机，具有控制互换性，可根据冷冻机的使用形式和使用目的实现最优控制，而且不需要排列与控制相对应的专门冷冻机。本冷冻机具有压缩制冷剂的变频驱动的压缩机和冷凝用此变频压缩机压缩的制冷剂的冷凝器，上述变频压缩机可适当切换成基于低压侧压力的cut-in/cut-out控制、低压侧压力恒定控制及外部输入实时控制而进行控制。

Provided is a refrigerator which has control interchangeability and can realize optimal control according to the usage form and purpose of the refrigerator without requiring special refrigerators arranged corresponding to the control. This refrigerator has an inverter-driven compressor for compressing refrigerant and a condenser for condensing refrigerant compressed by this inverter compressor, and the above-mentioned inverter compressor can be appropriately switched to cut-in/cut-out control based on low-pressure side pressure, It is controlled by constant pressure control on the low pressure side and real-time control by external input.

冷冻机 freezer

技术领域technical field

本发明涉及一种冷冻机，尤其是涉及用于店铺等的冷冻冷藏设备及恒温室等中的冷冻机。The present invention relates to a refrigerator, and in particular to a refrigerator used in refrigerating and refrigerating equipment in shops and the like, and in thermostatic chambers.

背景技术Background technique

在具有作为室外机的冷凝器的冷冻机中，使用侧连接着冷冻柜、冷藏柜、恒温室等各种利用设备的蒸发器，因此通常利用通过冷冻循环的低压侧压力进行ON/OFF运转。即，陈列柜等的利用设备基于柜内温度独立地对与冷冻机连接的制冷剂配管中设置的开关阀进行ON/OFF控制，冷冻机侧检测出低压力侧压力，在连接的所有冷冻机都停止时，排出制冷剂不流向利用设备的蒸发器，检测低压力侧压力的下降而停止冷冻机。In a refrigerator with a condenser as an outdoor unit, the use side is connected to the evaporator of various utilization equipment such as freezers, refrigerators, and thermostatic chambers, so the ON/OFF operation is usually performed using the low-pressure side pressure of the refrigeration cycle. That is, the utilization equipment such as a display cabinet independently controls ON/OFF of the on/off valve provided in the refrigerant piping connected to the refrigerator based on the temperature inside the cabinet, and the low-pressure side pressure is detected on the refrigerator side, and all connected refrigerators When both are stopped, the discharged refrigerant does not flow to the evaporator of the utilization equipment, and the drop of the pressure on the low pressure side is detected to stop the refrigerator.

近年，这样的冷冻机，为了提高节能性，也增加了用变频装置等可改变压缩机能力的设备。In recent years, in such refrigerators, in order to improve energy saving, devices that can change the capacity of the compressor by using an inverter or the like have been added.

所以，如专利文献1或专利文献2所记载，提出了具有可进行能力控制的压缩机的冷冻机。Therefore, as described in Patent Document 1 or Patent Document 2, a refrigerator having a capacity-controllable compressor has been proposed.

在这样的冷冻机中，控制压缩机的能力、以使低压侧压力恒定，或者，在具有变频装置的冷冻设备中，控制变频装置的输出频率。结果，可以控制压缩机的能力到最佳状态，提高节能性。In such a refrigerator, the capacity of the compressor is controlled so that the pressure on the low-pressure side becomes constant, or, in a refrigeration system having an inverter, the output frequency of the inverter is controlled. As a result, the capacity of the compressor can be controlled to an optimum state, improving energy saving.

但是，在现有的冷冻设备中，将这样的能力可变的冷冻机和过去的能力恒定控制(使用定速的压缩机)的冷冻机替换的情况下，作为冷冻机可以改变其能力以控制低压侧压力为恒定，但是，在陈列柜等的利用设备侧的减压装置的毛细现象或减压量的控制响应性不充分时，不能紧随压缩机的能力变化，会导致冷冻能力过大以至利用侧设备的蒸发器冻结，反而产生冷冻能力不足、不能充分冷却等其互换性问题。However, in the existing refrigerating equipment, when such a variable capacity refrigerating machine is replaced with a conventional refrigerating machine with constant capacity control (using a constant speed compressor), the capacity of the refrigerating machine can be changed to control The pressure on the low-pressure side is constant, but if the capillary phenomenon of the decompression device on the equipment side or the responsiveness of the control of the decompression amount is not sufficient, such as a showcase, it will not be able to follow the change in the capacity of the compressor, resulting in excessive refrigeration capacity. As a result, the evaporator of the equipment on the utilization side freezes, resulting in insufficient refrigeration capacity, insufficient cooling, and other interchangeability problems.

专利文献1：日本特开昭63-140254号公报Patent Document 1: Japanese Patent Laid-Open No. 63-140254

专利文献2：日本特开平10-141784号公报Patent Document 2: Japanese Unexamined Patent Publication No. H10-141784

发明内容Contents of the invention

本发明考虑了上述问题而做出，其目的在于提供一种具有通用性的冷冻机，具有控制互换性，对于冷冻机的使用方式、使用目的可进行最优控制，而且，不需要排列与控制对应的专用冷冻机。The present invention is made in consideration of the above-mentioned problems, and its purpose is to provide a general-purpose refrigerator, which has control interchangeability, and can optimally control the use mode and purpose of the refrigerator, and does not require arranging and Control the corresponding special refrigerator.

实现上述目的的冷冻机，至少设置了3个控制模式，在现有的陈列柜等利用侧设备中也可以进行控制模式的选择，可进行连接运行。The refrigerating machine that achieves the above-mentioned purpose is provided with at least three control modes, and the control mode can also be selected in the existing use-side equipment such as a display cabinet, and can be connected and operated.

即，本发明涉及的冷冻机，具有压缩制冷剂的压缩机、可变速驱动该压缩机的变频装置、以及冷凝由该压缩机压缩的制冷剂的冷凝器，该冷冻机还包括：检测冷冻循环的低压侧压力的低压侧压力传感器；该低压侧压力传感器的输出端子；以及从外部输入电压或电流的模拟输入端子；还具有控制电路，切换基于低压侧压力的变频装置的开关控制、低压侧压力恒定控制和外部输入实时控制；其中，该低压侧压力恒定控制对变频装置的输出频率进行控制，以使低压侧压力恒定；该外部输入实时控制与从上述模拟输入端子输入的模拟信号成比例地控制变频装置的输出频率。That is, the refrigerator according to the present invention has a compressor for compressing refrigerant, an inverter device for driving the compressor at a variable speed, and a condenser for condensing the refrigerant compressed by the compressor, and further includes: The low-pressure side pressure sensor of the low-pressure side pressure; the output terminal of the low-pressure side pressure sensor; and the analog input terminal for inputting voltage or current from the outside; it also has a control circuit to switch the switch control of the frequency conversion device based on the low-pressure side pressure, the low-pressure side Constant pressure control and external input real-time control; wherein, the low-pressure side constant pressure control controls the output frequency of the frequency conversion device to keep the low-pressure side pressure constant; the external input real-time control is proportional to the analog signal input from the above-mentioned analog input terminal To control the output frequency of the frequency conversion device.

如果采用本发明的冷冻机，可实现控制互换性，可根据冷冻机的使用形式和使用目的进行最优控制，因此，可提供不需要排列与控制对应的专门冷冻机的通用性高的冷冻机。According to the refrigerating machine of the present invention, control interchangeability can be achieved, and optimal control can be performed according to the usage form and purpose of the refrigerating machine. Therefore, it is possible to provide a highly versatile refrigerating machine that does not require special refrigerating machines corresponding to the arrangement and control. machine.

附图说明Description of drawings

图1是组装有本发明涉及的冷冻机的冷冻柜的概念图。FIG. 1 is a conceptual diagram of a freezer incorporating a freezer according to the present invention.

图2是设置在本发明涉及的冷冻机中的控制电路的概念图。Fig. 2 is a conceptual diagram of a control circuit provided in the refrigerator according to the present invention.

图3是设置在本发明涉及的冷冻机中的控制电路板的概念图。Fig. 3 is a conceptual diagram of a control circuit board provided in the refrigerator according to the present invention.

图4是用于本发明涉及的冷冻机的控制电路中的控制模式设定开关的说明图。Fig. 4 is an explanatory diagram of a control mode setting switch used in the control circuit of the refrigerator according to the present invention.

图5a～5d是本发明涉及的冷冻机的控制模式的说明图。5a to 5d are explanatory diagrams of control modes of the refrigerator according to the present invention.

图6是本发明涉及的冷冻机的控制流程图。Fig. 6 is a control flowchart of the refrigerator according to the present invention.

具体实施方式Detailed ways

下面，参照附图说明本发明涉及的冷冻机的一个实施方式。Hereinafter, one embodiment of the refrigerator according to the present invention will be described with reference to the drawings.

图1是作为组装有本发明涉及的冷冻机的利用设备的陈列柜的概念图。FIG. 1 is a conceptual diagram of a showcase as a utilization device incorporating a refrigerator according to the present invention.

如图1所示，本发明的冷冻机1，由在作为利用设备的三台冷冻柜2的柜本体3中分别内置的三个蒸发器4构成冷冻循环5。As shown in FIG. 1 , a refrigerator 1 according to the present invention constitutes a refrigeration cycle 5 with three evaporators 4 built in cabinet bodies 3 of three freezers 2 serving as utilization equipment.

冷冻机1包括：压缩制冷剂并具备直流无刷电动机6a的压缩机6，冷凝在该压缩机6中被压缩的制冷剂的冷凝机7，以及往该冷凝机7送冷却空气的冷凝用送风机8。另一方面，柜本体3分别具有上述蒸发器4和送风给该蒸发器4的蒸发用送风机9。The refrigerator 1 includes a compressor 6 that compresses refrigerant and includes a DC brushless motor 6a, a condenser 7 that condenses the refrigerant compressed by the compressor 6, and a condensing blower that sends cooling air to the condenser 7. 8. On the other hand, the cabinet main body 3 has the above-mentioned evaporator 4 and the blower 9 for evaporation which blows air to this evaporator 4, respectively.

冷凝机7经节点10d、以并列状态分别设置的节点11、开关阀12、电子膨胀阀13v或毛细管(capillary tube)13c，并通过输出侧配管14与多个例如三个蒸发器4连接，而且，该各蒸发器4经节点15及节点10s并通过吸入侧配管16与压缩机6连接，形成冷冻循环5。The condenser 7 is connected to a plurality of, for example, three evaporators 4 through an output side piping 14 via a node 10d, a node 11 provided in parallel, an on-off valve 12, an electronic expansion valve 13v, or a capillary tube 13c, and Each of the evaporators 4 is connected to the compressor 6 via the node 15 and the node 10s through the suction side piping 16 to form the refrigeration cycle 5 .

如图2所示，冷冻机1中设置着具有冷冻机用微控制单元(MicroControl Unit，以下称为MCU)211的冷冻机控制电路21、和与此冷冻机控制电路21可进行UART(Universal Asynchronus ReceiverTransmitter，通用异步收发)通信的变频电路(或装置)31。冷冻机控制电路21设置在冷冻机控制电路板24上，变频电路31设置在变频电路板32上。As shown in FIG. 2 , the refrigerator 1 is provided with a refrigerator control circuit 21 having a refrigerator micro control unit (MicroControl Unit, hereinafter referred to as MCU) 211, and with this refrigerator control circuit 21, UART (Universal Asynchronous) can be performed. ReceiverTransmitter, a frequency conversion circuit (or device) 31 for universal asynchronous transceiver) communication. The refrigerator control circuit 21 is arranged on the refrigerator control circuit board 24 , and the frequency conversion circuit 31 is arranged on the frequency conversion circuit board 32 .

具有冷冻机用MCU211的冷冻机控制电路21，与陈列柜本体3中设置的控制电路可以进行通信，通过安装在如图1所示的吸入侧配管16上的低压侧压力传感器16a、高压侧压力传感器以及控制器，连接着风扇电动机8a、排出温度传感器213、冷凝器温度传感器7a以及外气温度传感器214。The refrigerating machine control circuit 21 having the refrigerating machine MCU 211 can communicate with the control circuit provided in the showcase body 3 through the low pressure side pressure sensor 16a installed on the suction side piping 16 as shown in FIG. The sensor and the controller are connected to the fan motor 8a, the discharge temperature sensor 213, the condenser temperature sensor 7a, and the outside air temperature sensor 214.

变频电路31具有：经由噪音滤波器25与电源26连接的整流电路311，与此整流电路311的输出端连接的平滑电容器312，与此电容器312的两端连接并通过切换输出规定频率的电压的变频主电路313，驱动此变频主电路313的变频用MCU314。通过位置检测装置318向此变频用MCU314输入连接在变频主电路313上的压缩机6的直流无刷发动机6a的转子位置信息，还控制设置在电源26和整流电路311之间的、由电抗器315和开关电路36构成的短路电路317。此短路电路317在由电源供电的交流电压波形过零点附近，利用电抗器使交流电源短路规定时间，以改善功率。The frequency conversion circuit 31 has: a rectification circuit 311 connected to the power supply 26 via the noise filter 25, a smoothing capacitor 312 connected to the output terminal of the rectification circuit 311, and a capacitor connected to both ends of the capacitor 312 to output a voltage of a predetermined frequency by switching. The frequency conversion main circuit 313 drives the frequency conversion MCU 314 of the frequency conversion main circuit 313 . Input the rotor position information of the DC brushless motor 6a of the compressor 6 connected to the frequency conversion main circuit 313 to this frequency conversion MCU 314 through the position detection device 318, and also control the reactor provided between the power supply 26 and the rectification circuit 311. 315 and the short-circuit circuit 317 that switch circuit 36 constitutes. The short-circuit circuit 317 uses a reactor to short-circuit the AC power supply for a predetermined time near the zero-crossing point of the AC voltage waveform supplied by the power supply to improve power.

如图3所示，在冷冻机控制电路21中，除了图2所示以外，经各端子连接着压缩机壳体温度调节器6b、高压开关216、除霜加热器联锁用端子215。而且，还在设置有冷冻机控制电路21的冷冻机控制电路板24上，安装着外部输入端子217、通信输入端子218、异常输出无电源触点端子219、电磁阀用电源控制端子220、与变频电路31进行UART通信的通信端子221、以及与变频电路31连接的电源端子222，并且，还设置着设定成为目标的低压侧压力的低压侧压力设定开关223及如图4所示的DIP开关即控制模式设定开关224。控制模式设定开关224可利用左侧的2个DIP开关选择下述的4种控制模式。As shown in FIG. 3, in the refrigerating machine control circuit 21, in addition to those shown in FIG. 2, the compressor casing temperature regulator 6b, the high pressure switch 216, and the defrosting heater interlock terminal 215 are connected via respective terminals. Moreover, on the refrigerator control circuit board 24 provided with the refrigerator control circuit 21, an external input terminal 217, a communication input terminal 218, an abnormal output non-power contact terminal 219, a solenoid valve power control terminal 220, and The frequency conversion circuit 31 carries out the communication terminal 221 of UART communication, and the power supply terminal 222 connected with the frequency conversion circuit 31, and is also provided with the low pressure side pressure setting switch 223 of setting the target low pressure side pressure and as shown in Fig. 4 The DIP switch is the control mode setting switch 224 . The control mode setting switch 224 can select the following four control modes by using the two DIP switches on the left side.

设置冷冻机时，施工人员通过切换冷冻机控制电路板24的控制模式设定开关224，冷冻机1可切换成4种控制模式。各开关的位置和被选择的控制模式如图4所示。When installing the refrigerator, the construction personnel switch the control mode setting switch 224 of the refrigerator control circuit board 24, and the refrigerator 1 can be switched into four control modes. The position of each switch and the selected control mode are shown in Figure 4.

4种控制模式如图5a所示，第一种是低压恒定控制模式(M1)，控制频率以使冷冻循环的低压侧成为由低压侧压力设定开关223设定的低压侧压力，是主要采用的控制模式，是在蒸发器侧多分支冷冻循环中最适合的高节能性的控制模式。The four control modes are shown in Figure 5a. The first is the low-pressure constant control mode (M1), which controls the frequency so that the low-pressure side of the refrigeration cycle becomes the low-pressure side pressure set by the low-pressure side pressure setting switch 223, which is mainly adopted The control mode is the most suitable high energy-saving control mode in the multi-branch refrigeration cycle on the evaporator side.

如图5b所示，第二种是ON/OFF控制模式(M2)，是在低压侧压力中进行cut-in/cut-out的方式，在现有的利用侧设备的减压装置等在构造及机构上对应不了压缩机的能力可变控制时使用。在此模式下，压缩机在起动、停止以外是按设定的恒定频率(与商用电源频率大致相等)运行，用由低压侧压力设定开关223设定的低压侧压力对压缩机进行ON/OFF控制，是和使用了过去控制方式的恒定速压缩机的冷冻机具有互换性(替换容易性)的控制方式。As shown in Figure 5b, the second is the ON/OFF control mode (M2), which is a cut-in/cut-out method in the low-pressure side pressure. It is used when the mechanism cannot correspond to the capacity variable control of the compressor. In this mode, the compressor runs at a set constant frequency (approximately equal to the frequency of the commercial power supply) other than starting and stopping, and the compressor is turned ON/OFF with the low-pressure side pressure set by the low-pressure side pressure setting switch 223. OFF control is a control method that is compatible (ease of replacement) with a refrigerator using a conventional constant-speed compressor.

如图5c所示，第三种是模拟指令控制模式(M3)，是外部输入实时控制，控制与对外部输入端子的输入信号的电压或电流值成比例的频率运转，并且与成套设备制造商设置的模拟输出指示装置(控制器)相对应，是用于对应特殊的利用侧设备的控制方式。As shown in Figure 5c, the third is the analog command control mode (M3), which is external input real-time control, controls the frequency operation proportional to the voltage or current value of the input signal to the external input terminal, and is compatible with the complete equipment manufacturer Corresponding to the provided analog output indicating device (controller), it is used to correspond to the control method of the special utilization side equipment.

如图5d所示，第四种是通信指令控制模式(M4)，采用位于利用侧设备或与利用侧设备之间的专门控制器，并通过通信码来指定变频装置的输出频率。此控制用于希望进行柜内温度恒定的精密控制的场合。此时，被指定的频率是使柜内温度达到设定温度的、按照事先确定的控制规则来确定的频率。此控制方式是最适合冰柜等装配式储藏柜的控制方式。As shown in Figure 5d, the fourth is the communication command control mode (M4), which uses a special controller located at or between the equipment on the utilization side, and specifies the output frequency of the frequency conversion device through the communication code. This control is used in occasions where precise control of a constant temperature in the cabinet is desired. At this time, the designated frequency is a frequency determined in accordance with a predetermined control rule to bring the temperature in the cabinet to the set temperature. This control method is the most suitable control method for prefabricated storage cabinets such as freezers.

并且，说明了运转控制模式的切换通过设置在冷冻机的控制电路板上的DIP开关进行的例子，但是，通信指令控制模式(M4)下，如图3所示，使来自设置在冷冻机外的控制器33的输入经过外部通信用输入端子225、通信输入端子218，只要有正规的输入，那么忽略切换开关而优先执行通信侧的指令，这样，通信利用时不需要DIP开关的设定，很方便。In addition, the example in which the switching of the operation control mode is performed by the DIP switch provided on the control circuit board of the refrigerator is described. However, in the communication command control mode (M4), as shown in FIG. The input of the controller 33 passes through the external communication input terminal 225 and the communication input terminal 218. As long as there is a normal input, then the switching switch is ignored and the instruction on the communication side is preferentially executed. In this way, the setting of the DIP switch is not required when the communication is used. very convenient.

下面，按照图6所示的控制流程对本发明的冷冻机的控制方法进行说明。Next, the control method of the refrigerator according to the present invention will be described according to the control flow shown in FIG. 6 .

在冷冻柜2的设置时或使用开始时，操作图4所示的控制模式设定开关40，然后设定图5a～5d所示的任一个希望的运转控制模式。When the freezer 2 is installed or started to be used, the control mode setting switch 40 shown in FIG. 4 is operated, and any desired operation control mode shown in FIGS. 5a to 5d is set.

当启动冷冻柜2并开始冷冻机1的运行时，冷冻机用MCU211判断控制模式设定开关40被设定成哪个运转控制模式。(S1)When the freezer 2 is activated and the operation of the refrigerator 1 is started, the refrigerator MCU 211 determines which operation control mode the control mode setting switch 40 is set to. (S1)

若判断为设定成低压恒定控制模式(M1)，由图1所示的低压侧压力传感器16a检测出对吸入侧配管16的压力即低压侧的压力，判断此低压侧压力Ps是否比压力P1(能力控制用目标低压设定值)大(S2)，当此低压侧压力Ps比压力P1大时，不进行增加变频输出频率并增加冷冻机1的制冷能力的运转(S3)；当此低压侧压力PS比恒定压力P1小时，下调变频输出频率，进行降低冷冻机1的制冷能力的运转(S4)。并且，在低压恒定控制模式控制(M1)时，也与下面叙述的ON/OFF控制模式(M2)的S8相同，当比目标低压值更低时，判断为利用侧设备全部停止，压缩机停止(变频装置输出成为[0])工作。(省略流程图)If it is determined that the low-pressure constant control mode (M1) is set, the pressure on the suction side piping 16, that is, the pressure on the low-pressure side is detected by the low-pressure side pressure sensor 16a shown in FIG. (Target low pressure setting value for capacity control) is large (S2), when the pressure Ps of the low pressure side is greater than the pressure P1, the operation of increasing the frequency conversion output frequency and increasing the refrigeration capacity of the refrigerator 1 is not performed (S3); When the side pressure PS is smaller than the constant pressure P1, the inverter output frequency is lowered to lower the cooling capacity of the refrigerator 1 (S4). In addition, in the low pressure constant control mode control (M1), it is the same as S8 in the ON/OFF control mode (M2) described below. When it is lower than the target low pressure value, it is judged that all the equipment on the utilization side is stopped, and the compressor is stopped. (The output of the frequency conversion device becomes [0]) work. (Omit the flowchart)

如上所述，在低压恒定控制模式(M1)中，进行图5a所示的使低压侧压力恒定的控制。As described above, in the low-pressure constant control mode (M1), the control for making the low-pressure side pressure constant is performed as shown in FIG. 5a.

当判断为设定成ON/OFF控制模式(M2)时，由低压侧压力传感器16a检测出低压侧的压力，判断此低压侧压力Ps是否比恒定(规定)压力P2大(S5)，当此低压侧压力Ps比压力P2大时，变频输出频率固定为Fc运行(S6)，而且，使压力P2成为cut-in压力值(S7)；当低压侧压力Ps比压力P2小时，变频输出置为OFF，停止冷冻机1(S8)，压力P2设定为cut-out压力值(S9)。When it is determined that the ON/OFF control mode is set (M2), the pressure on the low pressure side is detected by the low pressure side pressure sensor 16a, and it is judged whether the pressure Ps on the low pressure side is greater than the constant (specified) pressure P2 (S5). When the pressure Ps on the low-pressure side is greater than the pressure P2, the frequency conversion output frequency is fixed at Fc (S6), and the pressure P2 becomes the cut-in pressure value (S7); when the pressure Ps on the low-pressure side is smaller than the pressure P2, the frequency conversion output is set to OFF, stop the refrigerator 1 (S8), and set the pressure P2 as the cut-out pressure value (S9).

结果，在ON/OFF控制模式(M2)下，进行利用图5b所示的低压侧压力进行的开关控制。As a result, in the ON/OFF control mode (M2), switching control using the low-pressure side pressure shown in FIG. 5b is performed.

当判断为设定在模拟指令控制模式(M3)时，A/D变换外部输入端子217的输入电流(S10)，并按照与此A/D变换值成比例的输出频率运行变频装置(S11)。When it is determined that it is set in the analog command control mode (M3), A/D converts the input current of the external input terminal 217 (S10), and operates the frequency conversion device according to the output frequency proportional to the A/D conversion value (S11) .

在上述的模拟指令控制模式(M3)中，进行图5c所述外部输入实时控制。In the above-mentioned analog command control mode (M3), the external input real-time control described in Fig. 5c is performed.

当判断为设定在通信指令控制模式(M4)时，按照与通过通信得到的频率指令对应的输出频率来运行变频装置(S12)。When it is determined that the communication command control mode is set (M4), the inverter is operated at the output frequency corresponding to the frequency command obtained through communication (S12).

在上述的通信指令控制模式(M4)中，进行图5d所述的柜内温度恒定控制。In the above-mentioned communication command control mode (M4), the temperature constant control in the cabinet as shown in FIG. 5d is performed.

根据如上所述的本实施方式的冷冻机，通过低压侧压力将由变频装置驱动的压缩机适当切换成开关控制、低压侧压力恒定控制及外部输入实时控制而进行控制，因此具有控制互换性，可以实现对应冷冻机的使用形式、使用目的的最优控制，而且不需要排列与控制对应的专门冷冻机。再者，在本实施例中还具有利用通信可指示频率的通信模式，更加提高了通用性。According to the refrigerating machine of the present embodiment as described above, the compressor driven by the inverter device is controlled by appropriately switching between on-off control, low-pressure side pressure constant control, and external input real-time control according to the low-pressure side pressure, so it has control compatibility, It is possible to achieve optimal control corresponding to the usage form and purpose of the refrigerator, and it is not necessary to arrange and control specialized refrigerators. Furthermore, in this embodiment, there is also a communication mode in which the frequency can be indicated through communication, which further improves the versatility.

1. refrigerator has the converter plant of compressor, this compressor of variable speed drive of compressed refrigerant and condensation by the condenser of the cold-producing medium of this compressor compresses, it is characterized in that,

Comprise: the low-pressure lateral pressure sensor that detects the low-pressure lateral pressure of freeze cycle; The lead-out terminal of this low-pressure lateral pressure sensor; And from the analog input terminal of external input voltage or electric current;

Also have control circuit, switch switch control, the constant control of low-pressure lateral pressure and outside input control in real time based on the converter plant of low-pressure lateral pressure; Wherein, the constant control of this low-pressure lateral pressure is controlled the output frequency of converter plant, so that low-pressure lateral pressure is constant; The output frequency with the analog signal proportional ground control converter plant of importing from above-mentioned analog input terminal is controlled in this outside input in real time.