JPS611945A - Refrigerating machine - Google Patents

Abstract

PURPOSE:To contrive to prevent a high pressure switch from actuating by effectively suppressing the rise of high pressure by a method wherein the rise of the high pressure is finely followed up by the increase of the cooling capacity of a condenser when the high pressure rises due to the passing-away of disturbance. CONSTITUTION:When the cooling capacity of a condenser 2 increases at the time point A, at which the disturbance such as strong wind or the like is applied, and consequently high pressure P starts to lower, the rotational frequency of an outdoor supply fan 2a starts to lower gradually. When the high pressure P remains not to converge at the set value Pset, the rotatio of the fan gradually comes to stop. When the cooling capacity of the condenser 2 decreases by being accompanied by the passing-away of disturbance, which occurs at the time point B, and consequently the high pressure Prises so high as to exceed the set value Pset, the fan 2a runs immediately at the predetermined low or medium rotational frequency R0 so as to control the high pressure P in order to converge it at the set value Pset. Consequently, the cooling capacity of the condenser 2 increases by finely following up to the rise of the high pressure P, resulting in effectively suppressing the rise of the high pressure P so as to accurately converge the high pressure P at the set value Pset.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a refrigerator, and more particularly to an improvement in preventing an abnormal rise in high pressure in a refrigerant circulation system I/L.

(Prior art) Conventionally, as this type of refrigerator, for example, the Utility Model 5C)
As disclosed in Japanese Patent No. 65233, a refrigerant pressure detection means for detecting the refrigerant pressure in the refrigerant circulation system is provided, and the rotation speed of the condenser fan can be switched to two stages: low speed and high speed. When the high pressure in the refrigerant circulation system exceeds the set value for compressor protection, the rotation of the condenser blower fan is switched from the low speed side to the high speed side.r: By increasing the cooling capacity of the condenser, the high pressure It is known that the compressor can be operated continuously without activating the high pressure switch by suppressing the increase in pressure above a set value.

(Problem to be Solved by the Invention) However, in the above-mentioned conventional system, when the Karasue pressure is suppressed from increasing by 1, the high pressure R becomes less than the set value as the condenser fan shifts to high-speed rotation. The pressure may drop too much, so in order to maintain good operating conditions of the refrigerator, it is desirable to maintain and control the high pressure at the set value.

Therefore, depending on the magnitude relationship with the set value, such as high pressure, etc., a control means is provided to increase or decrease the rotation speed of the condenser's blower fan in multiple stages or in the pre-stage. By doing so, it is possible to directly control the convergence and hold the high pressure (approximately setting it).

However, in Emono, the time constant of the first speed change of the blower fan is set large because it is necessary to maintain and control the high pressure in a steady operating state of 17M cold with a small hunting width. However, in this case, various disadvantages may occur due to the delay in the speed change of the blower fan. However, if the condenser is installed outdoors, if a disturbance such as strong wind occurs in a situation where the outside temperature is low, the condenser's cooling capacity will decrease.
4] The ff1j force may increase significantly and the fan may stop rotating. At that time, once the disturbance has passed, the cooling capacity of the condenser will decrease and the high pressure will begin to rise, but at this time, the condenser's blower fan will continue to operate until the high pressure reaches the set value. It remains stopped and begins to rotate gradually with a predetermined large time constant when the set value is exceeded.For this reason, when the high pressure rises significantly, the condenser needs to be cooled in response to this pressure rise. If the increase in capacity does not go smoothly, the high-pressure switch may eventually operate, causing the compressor to shut down.

The present invention has been made in view of the above, and its purpose is to control the high pressure to be maintained at the set value as described above, and when the disturbance disappears and the high pressure rises, the condenser is cooled. By making the increase in capacity follow this pressure increase effectively, the increase in high pressure can be effectively suppressed and the operation of the high pressure switch can be prevented. The aim is to ensure that the compressor can be operated continuously regardless of the situation.

(Means for Solving the Problems) In order to achieve the above objectives, the configuration of the present invention is shown in FIG.
Like, refrigerant 111! a refrigerant pressure detection means (10) for detecting the refrigerant pressure of the I-ring system (6); a fan stop detection means (15) for detecting that the blower fan (2a) of the condenser (2) has stopped; The pressure detection means (10) receives the output of
At) the blower fan (2a) of the F condenser (2)
control means (2) for controlling the rotation speed of
o), the refrigerant pressure detection means (10) and the fan stop detection means (15), and after the blower fan (2a) of the condenser (2) stops, the high pressure (P) is set to 1f.
a correction means (21) for correcting the control means (2o) so that when fl (P set ) is exceeded, the blower fan (2a) of the condenser (2) restarts at a predetermined low to medium rotational speed (RO); It is equipped with the following.

(Function) - With the configuration described in F, the present invention can prevent the occurrence of disturbances such as strong winds. 17 When the cooling capacity of the condenser (2) increases significantly and its blower fan (2a) stops rotating, if the disturbance subsides and the high EMI pressure rises above the set value, the condenser blower fan stops rotating. By immediately rotating the condenser at a predetermined low to medium speed, the increase in cooling capacity of the condenser follows the high pressure, effectively suppressing the increase in high pressure. , pressure sI! Continuous operation is possible (7).

(Example) Hereinafter, an example of the present invention will be described based on the drawings from FIG. 2 onwards.

Fig. 2 shows an example applied to an air conditioner, where (△) is an outdoor unit, (B) is an indoor unit, and the outdoor unit (A) includes a compressor (1) and a blower fan (2a). The indoor unit (B) includes an outdoor heat exchanger (2) having an expansion mechanism (3) and an indoor heat exchanger (4) having a blower fan (4a). Then, C1 each of the above devices (1) ~
(4) are connected by refrigerant piping (5)... to form a refrigerant circulation system (6), and the compressor (1)
By circulating the refrigerant in the direction shown by the arrow in the figure, an outdoor heat exchanger (
After the indoor air is exposed to the outside air in step 2), heat H1 is repeatedly absorbed from the indoor air by the indoor heat exchanger (4) which acts as an evaporator, thereby cooling the air-conditioned room. Note that (7) is an Akicomulator provided for the outdoor IJ (A>).

A refrigerant pipe (5) downstream of the outdoor heat exchanger (2) of the refrigerant circulation system (6) is provided with a refrigerant as a refrigerant pressure detection means for detecting the refrigerant pressure (high pressure) in the refrigerant pipe (5). A pressure sensor (10) is installed, and the refrigerant pressure h
The sensor 4f (10) is the compressor (1) and the outdoor unit (
△) and each blower fan (2a >,
(4a) to drive control I] controller (11)
is connected to enable signal transmission and reception.

As shown in FIG. 3, the controller (11) has a run/stop switch (12) disposed inside the air-conditioned room to switch between running and stopping, and a run/stop switch ( 12) and the above refrigerant pressure -7 = force sensor - microphone ITI receiving the output from (10)
a variable speed M position (14) for changing the speed of the outdoor blower fan (2a) of the outdoor heat exchanger (2); The fan stop detection means (15) is provided for detecting that the blower fan (2a) of the outdoor heat exchanger (2) (condenser) has stopped based on the presence or absence of output current, and the fan stop detection means (15) The output is input to the microcomputer (13).

Next, the operation of the microcomputer (13) will be explained based on the flowchart in FIG. ) and indoor ventilation fan (4a
), and in step S2, the outdoor blower fan (2a) of the outdoor heat exchanger (2) is initially gradually increased in rotation speed so that the starting current of the variable speed device (14) does not exceed the maximum allowable value. Raise it to perform a soft start. Then, in step S3, the rotation speed of the outdoor fan (2a) reaches the maximum rotation speed, and in step 84, the high speed rotation at this maximum rotation speed is forcibly continued for a predetermined period of time. do.

Subsequently, in step S5, the refrigerant pressure calender (10)
After reading the high pressure signal from , step S6'r high pressure (
It is determined whether P) is equal to the compressor (1) protection set value (Pset), and if P≠pset is NO, then in step 87, the high pressure (P) is set to the set value (pset).
Determine whether it exceeds p >ps'et, YES
In this case, in step S8, the variable speed device (14) is controlled to increase the rotation speed of the outdoor fan (2a) with a predetermined large time constant, thereby increasing the rotation speed of the outdoor heat exchanger (2).
by increasing the cooling capacity of the high pressure (P) to the set value (Ps
et). On the other hand, p < p se
If t is No, step 89'c determines whether or not there is an outdoor fan stop signal from the fan stop detection means (15);
If the outdoor fan stop signal has not been received (No), the variable speed device (14) is controlled in step S+o to lower the rotation speed of the outdoor fan (2a) by -9= with a predetermined large time constant. As a result, the capacity of the outdoor heat exchanger (2) is decreased to increase the high pressure (P) toward the set value (psel), and the process returns to step S5. In addition, if p = p set is YES in step S6, the high pressure (l) is set to the set value (Ps) by keeping the rotation speed of the outdoor fan (2a) as it is in step So.
et) and return to step s5.

Then, if the outdoor fan stop signal is received in step S9 (YES), the high pressure signal from the refrigerant pressure detection means (1o) is read in step S12, and the high pressure ( P) is the set value (pse
t), and if P≦pset is No, it is determined that it is not time to restart the outdoor fan (2a), and the process returns to step S12. On the other hand, if p>p set is YES, the process returns to step S12. In step S, it is determined that it is time to restart.
At M, the variable speed device (1) immediately restarts the outdoor fan (2a) at a predetermined low to medium rotation speed (Ro).
4) and return to step $5.

Therefore, by a series of processing operations from step 85 to step SII, the high pressure (1) and the set value (Pse
High pressure (P) is set according to the size relationship with t).
((Pset)) J: Increase/decrease the rotation speed of the blower fan (2a) of the outdoor heat exchanger (2) with a predetermined time constant'
l+′? The control means (20) is configured such that the control means (20) Further, if it is determined in step 89 that an outdoor fan stop signal has been received, that is, after the blower fan (2a) of the outdoor heat exchanger (2) has been stopped, each processing operation in steps 812 to S11 is performed. When the high pressure (P) exceeds the set value (pset), the blower fan (2a) of the outdoor heat exchanger (2) is immediately turned to a predetermined low to medium rotation speed (R
O) to restart the engine, usually at step S8.
A correction means (21) is configured to correct the control to increase the rotational speed of the outdoor fan (2a) which is gradually performed in the above.

Further, in this embodiment, a start detection means is configured to detect start by switching the run/stop switch (12) to the operation side, and the operation of the mine (13) causes condensation to occur at start. a first control means configured to rotate an outdoor fan (2a) of an outdoor heat exchanger (2) acting as a heat exchanger at high speed for a predetermined time (1); The second fan (2a) of the outdoor heat exchanger (2) is controlled in rotation speed so as to maintain the pressure (1) at a set value (pset).
and a control means.

Therefore, in the above embodiment, as shown in FIG. 5, the outdoor heat exchanger (
When the cooling capacity of 2) increases and the high pressure (P) begins to decrease, the rotation speed of the blower fan (2a) of the outdoor heat exchanger (2) gradually begins to decrease in order to reduce the cooling capacity, and the high pressure If (P) still does not converge to the set value (pset), the rotation will eventually stop. Then, after the lζ8 point at which the disturbance disappears, the cold IJI 1i of the outdoor heat exchanger (2)
(P) is 1:
When the temperature exceeds the set value (Pset), the outdoor fan (2a) immediately rotates at a predetermined low to medium rotation speed (RO) to control the convergence of the high pressure ([)) to the set value (Pset). will be held. Due to this, the outdoor heat exchanger (2)
The cooling capacity of is good against the increase in high pressure (P))0
The high pressure (P) will converge toward the set value (Pset) with high accuracy while effectively suppressing the high pressure (P). It is possible to effectively suppress the increase in high pressure (P), prevent the high pressure switch from operating, and perform continuous operation of the compressor (1).

Moreover, as shown in FIGS. 3 and 4, at startup,
The high pressure (,P) of the refrigerant circulation system (6) suddenly rises, but at the same time, the outdoor fan (2a) of the outdoor heat exchanger (2) immediately soft-starts.
By continuing the high speed rotation at the maximum rotation speed for the predetermined time (1), the high pressure (P) responds to the high speed rotation of the outdoor ventilation fan (2a) while effectively suppressing its sudden rise. The value is almost stabilized at a predetermined value (PO) that is less than the set value 1+fJ (Pset). For this reason, the high pressure (P) will change layers while responding well to the next rotational speed control of the outdoor fan (2a), and as a result, the high pressure (P) will move toward the set value (Pset). It transitions smoothly and converges to the set value (pset) with good accuracy (converges) within a short convergence period of 01.

Therefore, the high pressure switch is not activated due to a sudden increase in the high pressure (P) at startup (and the compressor <1> can be operated continuously).
) with highly accurate convergence control to the set value (pset) of the indoor heat exchanger (4) (evaporator) and compressor (1).
It is possible to effectively suppress the increase in the burden on people.

(Effects of the Invention) As explained above, according to the refrigerator of the present invention, when the high pressure in the refrigerant circulation system rises beyond the set value, the cooling capacity of the condenser increases even after disturbances such as strong winds have disappeared. The compressor can effectively follow the increase in high pressure based on the restart of the blower fan at a low to medium rotation speed, so the compressor can be operated continuously while effectively suppressing the increase in high pressure. Therefore, the operability of the refrigerator can be improved.
So I'm going to do it.

[Brief explanation of drawings]

Figure 1 is a block diagram of the configuration of the present invention, Figures 2 to 5
The figure shows an embodiment of the present invention, and Figure 2 is a refrigerant piping system diagram.
Figure 3 is a block diagram showing the internal configuration of the controller.
FIG. 4 is a flowchart for explaining the operation of the microcomputer, and FIG. 5 is a diagram for explaining how the high pressure converges to the set value. (2)...Outdoor heat exchanger (condenser), (2a)...
Blower fan, (6)... Refrigerant circulation system, (10>...
・Refrigerant pressure calenser (refrigerant pressure detection means), (15)...
・Fan stop detection means, (20)...control means, 2
1)...Correction means. Patent applicant: Daikine Raku Co., Ltd. JP-A-6L-1
945(7) Figure 4

Claims (1)

[Claims] (1) A refrigerant pressure detection means (10) for detecting the refrigerant pressure in the refrigerant circulation system (6), and a blower fan (2) for the condenser (2).
a) fan stop detection means (1) for detecting that the fan has stopped;
5) and receiving the output of the refrigerant pressure detection means (10),
The rotation speed of the blower fan (2a) of the condenser (2) is predetermined so that the high pressure (P) becomes the set value (Pset) according to the magnitude relationship with the set value (Pset) of the high pressure (P). a control means (20) for controlling increase/decrease with a time constant of , the refrigerant pressure detection means (10) and the fan stop detection means (15
), after the blower fan (2a) of the condenser (2) has stopped, if the high pressure (P) exceeds the set value (Pset), the blower fan (2a) of the condenser (2) will The control means (2) restarts at a medium to medium rotation speed (R_0).
A refrigerating machine comprising: a correction means (21) for correcting 0)