JPH0448167A - Refrigerating cycle device - Google Patents

Abstract

PURPOSE:To permit the arbitrary setting of an outlet temperature and the amount of outlet air by a method wherein the circulating amount from the discharging side of an expanding machine into the suction side of a compressor as well as the number of rotation of the compressor and the expanding machine are controlled based on the suction temperature of the compressor. CONSTITUTION:When a target outlet temperature and the target amount of outlet air are set, a suction temperature is measured by a temperature sensor 10. The opening degree theta of a damper is operated from a difference between the suction temperature and an outlet temperature through a formula while the number of rotation of a compressor 4 and an expanding machine 3 are operated by another formula. A damper driving motor 11 and a reduction gear 2 are driven to control the opening degree of the damper at theta and the number of rotation at N. According to this method, set outlet temperature and set amount of outlet air can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a gas compression type refrigeration cycle device, and more particularly to a device for controlling the blowout temperature and blowout air volume.

(Prior art) The air compression refrigeration cycle is a simple cycle that obtains cold air by directly compressing, releasing heat, and expanding outside air.
Used in aircraft, etc.

Examples of devices using conventional air compression refrigeration cycles include Japanese Patent Application Laid-Open No. 57-58598 and Japanese Patent Application Laid-open No. 56-1989.
116600, JP 62-120296, JP 57-130176, etc., and conventional low-temperature refrigeration cycle devices include JP 59-185949, JP 59-185949; Japanese Patent Application Publication 1986-
There are some disclosed in Japanese Patent No. 14065 and the like.

(Problems to be Solved by the Invention) The refrigeration cycle devices disclosed in these publications will be described in order. First, the refrigeration cycle devices disclosed in Japanese Patent Application Laid-open No. 57-58598 are designed to When the temperature decreases, the air flowing into the compressor is automatically switched to cabin circulation air (inside air), making it impossible to simultaneously introduce outside air (ventilation) and lower the blowout temperature. 116600
In the technology disclosed in the above publication, the high-pressure air compressed by the compressor bypasses the expander, so the power recovered by the expander is small, resulting in a poor coefficient of performance.

■ What is disclosed in JP-A-62-120296 is
As with the above item (■), the high-pressure air compressed by the compressor bypasses the expander, which reduces the power recovered by the expander, which worsens the coefficient of performance. No means for lowering the blowout temperature is disclosed.

■ What is disclosed in Japanese Utility Model Application Publication No. 57-130176 is a system in which a passage that bypasses the heat exchanger is provided in a communicating passage connecting a compressor, a heat exchanger, and an expander, and a passage that bypasses the heat exchanger is provided. Air is not cooled.

(1) The device disclosed in Japanese Patent Application Laid-Open No. 59-185949 utilizes a low-temperature refrigeration cycle, and bypasses the load at the beginning of the cycle to flow cold air to shorten the refrigeration time.

■ The one disclosed in JP-A-60-14065 utilizes a low-temperature refrigeration cycle, similar to the above-mentioned item (■).
This method bypasses the load and returns the refrigerant to the compressor, and does not disclose control of the bypass valve.

The present invention is distinguished from such prior art by
The object of the present invention is to recirculate a part of the cold air at the outlet of the expander to the suction side of the compressor, and to adjust the flow rate of the recirculated cold air, thereby controlling the blowout temperature and blowout air volume. The purpose of the present invention is to provide a type refrigeration cycle device.

(Means for solving the problem) For this purpose, the refrigeration cycle device of the present invention has, for example, a first
As shown in the figure, there is a compressor that compresses gas, a heat exchanger that removes heat from the gas discharged from the compressor, and the gas that has been removed from heat by the heat exchanger is expanded to become a low-temperature gas. an expander, a reflux passage for refluxing the gas at the outlet of the expander to the inlet of the compressor, a reflux amount adjusting means provided in the reflux passage, and a temperature sensor for detecting the suction temperature of the gas flowing into the compressor. , a target value setting means for setting a target blowout temperature and a target blowout air volume; and a rotation speed of the compressor and the recirculation amount based on the detection signal of the temperature sensor so that the set target blowout temperature and target blowout air volume are achieved. The present invention is characterized by comprising a control means for controlling the opening degree of the adjustment means.

(Function) When the target blowout temperature and the target blowout air volume are set, the rotation speed of the compressor and the opening degree of the recirculation amount adjusting means are controlled by the control means based on the intake air temperature signal from the intake temperature sensor. Then, the blown air that has the target blown air temperature and the target blown air volume is supplied into the room.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows an embodiment of the gas compression type refrigeration cycle apparatus of the present invention.

In FIG. 1, a compressor 4 and an expander 3 are coaxially fixed by a connecting shaft 13, and driving force is transmitted to them from a prime mover 1 via a transmission 2. A temperature sensor 10 is provided upstream of the intake port 6 of the compressor 4 to detect the intake temperature Tin of intake air. A heat exchanger 5 serving as a radiator is provided in a passage between the discharge side of the compressor 4 and the inlet side of the expander 3. A reflux passage 15 branches between the outlet part 3a of the expander 3 and the blow-off lower downstream thereof, and this reflux passage 15 is a passage between the inlet part 4a of the compressor 4 and the inlet 6 on the upstream side thereof. It is connected to the.

A damper 9 is provided in the middle of the reflux passage 15 as a reflux amount adjusting means for controlling the opening area of the passage.
The damper opening degree θ is controlled by a damper drive motor 11 as an actuator.

The control device 12 receives inputs such as the suction temperature signal of the temperature sensor 10, the rotational speed signals of the compressor 4 and the expander 3, and signals from the target value setting means for setting the target blowout temperature and target blowout air volume. Arithmetic processing is performed based on the signal, and the damper drive motor 11 is driven to the damper opening degree θ,
The transmission 2 is driven so that the rotational speed of the compressor 4 and the expander 3 is N.

The air taken in from the suction port 6 is compressed by the compressor 4 to become high temperature and high pressure, and the heat is radiated by the heat exchanger 5, and this high pressure air is given work by the expander 3 and becomes cool air and is blown out from the blowing lower. At this time, part of the cold air passes through the recirculation passage 15,
A flow rate corresponding to the damper opening degree θ of the damper 9 is returned to the inlet portion 4a of the compressor 4. The amount of cold air recirculated is controlled by the damper opening degree θ of the damper 9 and the rotation speed N of the compressor 4.

As shown in FIGS. 2 and 3, the damper opening degree θ is determined by the difference between the suction temperature Tin and the outlet temperature T out and the wind jlV.
It changes depending on aout/flow rate Va. Further, as shown in FIG. 4, the flow rate Va is determined depending on the rotational speed N of the compressor 4 and expander 3.

FIG. 5 is a flowchart showing an example of an operation in which the blowout temperature is controlled while the blowout air volume is constant.

When the driver sets the target temperature without talking (step 20) and the outlet temperature is measured (step 21), it is determined whether the outlet temperature is higher than the target temperature (step 22). If the blowing temperature is higher than the target temperature, the damper opening degree θ is increased (step 23), the amount of recirculated cold air is increased, and the recirculated cold air is further circulated through the refrigeration cycle to be lowered to a lower temperature. Then, the rotation speed N of the compressor 4 is increased. This is to compensate for the fact that when the amount of cold air returned increases, the amount of air from the blowout lower decreases accordingly. Then, the reflux amount increases (step 25), and the blowing temperature of the blowing lower chamber decreases (step 26). If the blowout temperature is lower than the target temperature, conversely, the damper opening degree θ is decreased (step 27), and the rotation speed N of the compressor 4 is decreased (step 28). Then, the amount of cold air recirculated decreases (step 29), and the blowing temperature increases (step 29).
Step 30). As a result, the blowing temperature approaches the target temperature.

Next, the arithmetic processing and output processing in the refrigeration cycle control device in this embodiment will be explained based on the flowchart shown in FIG.

When the target blowout temperature and target blowout air volume are set by the driver (step 40), the suction temperature is then measured by the temperature sensor 10 (step 41). Here, the damper opening degree θ is calculated using the following formula (2) based on the difference between the suction temperature Tin and the outlet temperature T out (step 42),
The rotational speed N of the compressor 4 and expander 3 is calculated according to the following equations (1) and (2) (step 43).

θ= f (Tin-Tout) □ ■N
=h(Va) □ ■Va = V
out/g (θ) ■Here,
The symbols f, h, g represent functions.

Then, the damper drive motor 11 and the transmission device 2 are driven to control the damper opening degree to the above-mentioned θ (step 44), and the rotational speed to the above-mentioned N (step 45). Thereby, the set blowing temperature and blowing air volume can be obtained.

In the above embodiment, the air cycle was explained, but it can also be used for gases other than air, and although a damper was used as a means for adjusting the amount of air recirculation, it is also possible to use means such as an electromagnetic control valve or a mechanically driven control valve. Of course it is possible.

(Effects of the Invention) As explained above, according to the refrigeration cycle device of the present invention, the reflux amount adjusting means is provided in the reflux passage from the expander discharge side to the compressor suction side, and the reflux amount can be varied. Since the rotation speed of the expander is controlled, there is an effect that the blowing temperature and the blowing air volume can be arbitrarily set.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing the configuration of an embodiment of the present invention, and FIG.
The figure is a characteristic diagram showing the relationship between the difference between suction temperature and outlet temperature and the damper opening degree, Figure 3 is a characteristic diagram showing the relationship between the air volume/flow rate ratio and the damper opening degree, and Figure 4 is a characteristic diagram showing the relationship between the air volume/flow rate ratio and the damper opening degree, and Figure 4 is the compressor rotation speed. FIG. 5 is a flowchart showing an example of the operation of a refrigeration cycle device, and FIG. 6 is a flowchart showing an operating system according to an embodiment of the present invention. 2... Transmission device (control means), 3... Expander, 4... Compressor, 5... Heat exchanger, 9... Damper (reflux amount adjustment means), 10... Suction Temperature sensor, 11... Damper drive motor (control means), 12... Control device (control means), 15... Reflux passage.

Claims (1)

[Claims] (1) A compressor that compresses gas, a heat exchanger that removes heat from the gas discharged from the compressor, and an expander that expands the gas from which heat was removed by the heat exchanger and turns it into a low-temperature gas. , a reflux passage for refluxing the gas at the expander outlet to the compressor inlet; reflux amount adjusting means provided in the reflux passage; a temperature sensor for detecting the suction temperature of the gas flowing into the compressor; and a target blowout. target value setting means for setting temperature and target blowout air volume; and control of the rotation speed of the compressor and the recirculation amount adjusting means based on the detection signal of the temperature sensor so that the set target blowout temperature and target blowout air volume are achieved. A refrigeration cycle device comprising a control means for controlling an opening degree.