JPS6183833A - Air conditioner - Google Patents

Abstract

PURPOSE:To recover surely lubricating oils standing in a refrigerating cycle into a compressor by a method wherein by use of throttle valves of the respective room units, passage areas of refrigerant paths in the respective room units are successively adjusted for smooth distribution of the refrigerants. CONSTITUTION:In the air conditioner units operating system, which constitutes one outdoor unit A with built-in types of compressor 1, heat-exchanger of outdoor use 3, and also a plurality of room units B, C, D, they are arranged in parallel connection, with the respective built-in types of heat-exchanger of indoor use 7 and throttle valve 8 to reduce an opening area of the refrigerant passage, a detecting measure for finding oil shortage time 20 to detect shortage of lubricating oil in the compressor 1 of outdoor unit A, and a control measure 21, which comprise a controlling function of taking-in outputted signals from the said detecting measure 20 so as to operate the air compressor 1 in a high power rate and another controlling function for opening and adjusting of opening rate of the refrigerant throttle valve 8 belonging to a certain minor unit among indoor units of B, C, D, and on the contrary, let the remaining throttle valves 8 to close in order that controlled operation are successively and repeatedly made within a given cycle time, are provided. Therefore, lubricating oils standing in the respective units are successively and completely recovered into air compressor together with refrigerant.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention is a method for cooling or heating a room using a refrigeration cycle.
The present invention relates to improvements in air conditioners, and particularly to measures to resolve the problem of oil shortage caused by compressor lubricating oil being discharged together with refrigerant and accumulating in the refrigeration cycle.

(Prior Art) Generally, in an air conditioner that air-conditions a room using a refrigeration cycle, when the compressor is operated at low capacity, the low pressure difference of the refrigerant becomes small.
) The medium circulation is reduced, and this I-completion is reduced.

The ability to return the lubricating oil discharged into the refrigerant during the refrigeration cycle to the compressor decreases, and if operation continues for a long time in this state, the accumulation of lubricating oil during compression increases. As a result, the compression may run out of lubricating oil, and as a result, high vortices, seizure, etc. may occur between the compression and the moving parts.

Therefore, conventionally, for example, the method disclosed in Japanese Utility Model Publication No. 57-41416 (1988) has been used to solve the problem.
1 hour/! : 5j Measurement 4 Tie 7 is installed, this low capacity single layer "l11.i; When the time reaches the predetermined time, the pressure 11if
By operating the machine at high capacity for a period of 0.1, l1ff gc will accumulate in the refrigeration cycle.
! By the way, it is known that β1 lubricating oil is collected in the compressor to eliminate the lubricating oil shortage in the compressor caused by the lubricating oil shortage described above (the problem that the invention seeks to solve). There are also so-called multi-system air conditioners in which multiple indoor units, each with a built-in indoor heat exchanger and throttling mechanism, are connected in parallel to one off-campus unit with a built-in outdoor heat exchanger. ,
On the other hand, when applying the above-mentioned conventional technology to solve the problem of lubricating oil shortage in the compressor caused by the oil pool, it is necessary to immediately adopt this technology since multiple indoor units are mounted on Ti. In other words, in multi-system 6, the total refrigerant passage area (total piping diameter) on the indoor unit side is smaller than the refrigerant passage area (piping diameter) on the outer unit side.
Since ljj is large (for example, about 1.4 times), even if the compressor is operated at high capacity, ljj 9! , the height of L and the pressure difference of 47 degrees that can recover the accumulated refrigerant may not occur, and for this reason, the refrigerant circulation is small and the refrigerant flow rate is low.
It is not possible to efficiently recover the lubricant 1111 accumulated during the refrigeration cycle, and it is not possible to reliably solve and eliminate the lack of lubricating oil.On the other hand, 8 indoor units 1.
Nami is <1 (+:+ E pair!, Shi, Shi (6D ILL
6171? :'.

If the throttle mechanism is configured with a variable throttle mechanism such as a Ti dynamic expansion valve, the throttle opening may become transiently small in response to a small load when oil accumulates.
The refrigerant flow resistance in this throttling mechanism is too large, making it difficult for the refrigerant to flow, making it more difficult to recover the accumulated lubricating oil.

The present invention has been made in view of the above points, and its purpose is to install J3 in one air conditioning rod of the above-mentioned Nuruji method.
When the compressor lubrication iIb is insufficient due to oil accumulation, the pressure mt* is operated at high capacity, and the refrigerant passage area in each indoor unit is adjusted appropriately in order, thereby reducing the large difference between high and low refrigerant pressures. In addition to generating pressure, even if the throttling mechanism has a throttling mechanism that changes according to the air conditioning load, the lubricating oil is reliably collected in the refrigerated cylinder by dividing the flow smoothly into the compressor. The objective is to reliably solve the problem of insufficient compressed lubricating oil caused by oil stagnation.

(Means for solving the problem) In order to achieve the above object, the solution number of the present invention is as follows.
(as shown in the figure), is a multi-type air conditioner, that is, one outdoor unit (A) containing a compressor (1) and an outdoor heat exchanger (3)? Indoor units (B) and (C) of the damaged base, which include L, 1 indoor heat exchanger (7) and a restriction adjustment valve (8) that adjusts the refrigerant passage area restriction (2). , (D> connected to !1rftll, an oil shortage detection means (20) for detecting a lubricant oil shortage in the compressor (1) of the above-mentioned off-campus), In response to the output of the shortage detection stage 1 (20), the compressor (1) is operated at high capacity.
, open the turbulence adjustment valve (8) of the indoor unit (1'3)-(1)) that is in operation.
In addition, the other indoor units are configured to have a f-stage (21) that sequentially repeats the adjustment of the aperture degree (8) in the closing direction at predetermined intervals. There is a C.

Hereinafter, by V, in the present invention, 1 contraction 1 caused by oil pooling
When the number of lubricating oils is fixed, the flow of refrigerant from the compressor increases, and the refrigerant passage on the indoor cornice side through which this refrigerant flows is empty. In the case of a variable orifice, the area is reduced and a large pressure difference is generated between the high and low pressures of the refrigerant. In this case, if the opening degree of the H+;A throttling mechanism is transiently small, the opening degree of the large variable restrictor in the refrigerant flow path increases, thereby reducing the flow rate and flow of the refrigerant. Quantity 1 woman increases, each room -1,
All the wet oil accumulated in the knit is sequentially collected together with the refrigerant by the compressor, and therefore, the oil caused by the oil accumulation is
This will definitely eliminate the uncertainty of the 2nd edition of the 3rd edition.

(Example) Hereinafter, an example of the present invention will be described with reference to FIG. 2 and the following drawings.

In Figure 2, (A) goes to outdoor-1 i, (13)
, (C), (D) i, a plurality of indoor units installed in different rooms (3 units), the outdoor unit: 1 unit <
A) has a compressor n (1) lubricated with lubricating oil, a four-way switching valve (2), and a jΣ external feeder fan (not shown) inside.
Each device (1) has a built-in outdoor heat exchanger (3), a receiver (4), and an accumulator (5).
- (5) are connected to each other by refrigerant piping (6) so that refrigerant can flow therethrough. In addition, each indoor unit (
8) to (D) have the same configuration, and each indoor heat exchanger (7) has 71 indoor air blowers (not shown) inside.
and an electric expansion valve (8) that can be adjusted in time, and the two devices (7) and (8) are connected to allow refrigerant flow through refrigerant piping. Electric expansion valve (8)
Accordingly, the sagging degree adjusting valve is configured to adjust the correction margin of the refrigerant passage area. Each of the above indoor units (B) to (r)) is connected to the outdoor unit (A) in a row of 1 p by refrigerant piping (10).
1) During operation, the refrigerant is circulated as shown by the solid arrow by switching the four-way selector valve (2) as shown by the no line.

Each indoor heat exchanger (7) absorbs heat from inside the room, and the outdoor heat exchanger (3) cools each room by repeatedly absorbing heat from the inside and releasing it to the outside air, while heating operation 81 to IL Yoro F
JJ exchange j? By switching (2) as shown by the broken line and circulating the refrigerant in a continuous manner, the hot reaction amount is reversed to the above and is made <' to heat the room.

In addition, for each indoor unit (B)・-(1)),
t, a room temperature detector (15) such as a thermistor that detects the room temperature, and a room temperature setter (16) consisting of a variable resistor to set a target temperature of 1 m inside the school;
Both devices are equipped with a differential numbing circuit (17) that controls one of the room temperature and the room temperature setting (C) in response to the command of (16) On the other hand, the compressor (1) is installed in the outdoor unit (△) at a rotation speed of 12n.
an inverter (18) with a capacity II fit;
In response to the frequency signal from the range difference stop circuit <17), a frequency setting signal corresponding to the deviation signal is outputted to the inverter (18), and at the same time, one unit h<Bn~<D> is output for each room.
The corresponding deviation effect circuit (
A control circuit (19) is provided for controlling the size according to the deviation 13 from the position (17). And the above control circuit (
19) is the pressure I based on the flow 17-1- in FIG.
In addition to detecting the lack of Mn oil in the II machine (1), this 1.1 1.7 M inverter (18 and 3 haze electric expansion j? It also has the function of (8) to send sakusen system 11117J to Haku other than Sako who responded to the deceit message.

To TI<K'b, in the float shade of Fig. 3,'
A, Step S + 'T' Check the frequency setting signal box for the inverter (18) and determine if the load of the compressor (1) exceeds a predetermined value (I0 or more) or 100. No
17) Ifl <, +,: i, 1. , rE
, I hostage 1jW (1) I > , l'I'I It is determined that there is no occurrence of lubricating oil shortage, and in step S2, the
is set to "0" and returns to step S1. On the other hand, /f contraction R< 1) '7) (1 load is given bi L
;l 'F )Y E S (DI threshold 67 Nij;L
Sufu Sufu S 3 T::'? MaT nir -l
J A-1111 Sieve Tanora, Step SJ-ci
'n'r place-L lr+ l:n l-1) Determine whether it is older or older, and if it is NO for -dori, I
Insufficient lubricating oil of rice machine 1) e j, F lh7
It is determined that there is no C, and the process returns to step 81 above.

On the other hand, in the case of YES (T≧T1) in the above step S4, it is determined that a lubricant shortage has occurred in the pressure lubricant (1), and the process proceeds to step S5, where the inverter (18 ) to output the highest frequency and setting signal to maximize (I hikate) 1 rice 1 number (1)
In step S6, turn on the electric expansion valve (8) of one indoor unit 1-(B) and turn it on to the indoor unit (C).
, (D) closes the electric expansion valve (8), and the compressor (1)
Tonden is from! ,: All Φ of refrigerant is heated in three indoor heat exchangers! l
! Inside the container 7. The l'i!i ring is applied only to the Iwanai heat exchanger (7) of (leek) - (+3 >), and this is continued for a predetermined period of 111 in step S7.7 After that, in step 8, the current epidemic is : 1-1-(C) electric expansion valve (8
) as a commandment ■'' indoor song 1~(B), <D>
Close the 1-'3i' (8) and transfer all the refrigerant from the compressor (1) indoors to the indoor heat exchanger 1-2 (C).
Only the oyster (7) is circulated, and this is continued for a predetermined time in step S9. After that, in step SIQ, fully open the electric 8-tension valve (8) of the next indoor unit (I), and then open the electric expansion valves (8) of the other indoor units (B) and (C). Close and compress the refrigerant (all the refrigerant from the leak (1) is circulated only to the indoor heat exchangers (7) of the indoor units 1 to (D), and this continues for a predetermined time in step Sn and ends,
After j and s, C is determined according to the deviation signal of each pot difference extraction circuit (17).
Impark (18) J5 and 3 electric expansion t'r
Control (8) and step S again! Return to

”, in the above steps S+ and Sa, the compressor (
1) If the operating state is below the specified capacity,
Compressor (1)
Oil shortage (Samurai 1 power output f
It constitutes one stage (20). Also, ST 77 S 5
Due to the subsequent speedy operation, compression is performed by high-efficiency gradient operation of (1) and also by
), the electric expansion valves (8) of some indoor units are fully open, and the electric expansion valves (8) of other indoor units are fully open, and this process is repeated at predetermined time intervals. This constitutes a crying control means <21>.

Although not shown in chart 70 of FIG. If the refrigerant is not flowing to the indoor heat exchanger (7), either the refrigerant is not distributed to it, or the refrigerant is circulated to the indoor heat exchanger (7) by listening to the corresponding electric expansion valve f' (8), but the indoor heat exchanger (7) is By stopping the delivery fan (7a), it is possible to ensure comfortable air conditioning without overcooling or overheating the room. During recovery, the rotation speed of the outdoor fan of the outdoor heat exchanger (3) is controlled to reduce the air volume, and during cooling, frost (= f In addition, during heating, it is possible to prevent the operation ty, ti: due to the increase in condensing temperature during compression protection.

Therefore, in the first column of implementation, the compression) is (1)
If the operation is below the specified capacity and the failure is TL for a period of time
By tt jecJ, the lubrication of the compression I (1)
It gets mixed into the refrigerant! ζ6 is discharged from the compressor (1) to cold A1 and J (and accumulates in each indoor court <13) to (D) of the refrigerant circulation system, and as a result, the compression is caused by the lack of lubricating oil in (1). If this occurs (thank you)
b. Assuming that the compression unit (1) is operated at maximum capacity, the opening of the electric expansion valve (8) of the indoor L unit (B) will initially change from a small opening corresponding to the load of the compression building. I'm fully open, my eyes are 11! ! Indoor Konits 1~(C).

Since the electric expansion valve (8) in (D) is fully opened, the area of the refrigerant passage on the inside (B) and (D) sides is large enough to collect the accumulated lubricating oil. Based on the operation at maximum capacity of the L compressor (number (i)), J"Y i?
iθ■? :'When a difference in the amount of human power i11 occurs between FI low power and refrigerant circulation 1MA and 10F, the flow rate of refrigerant increases.
The lubricating oil moistened in the unit (13) inside y is reliably collected.

It's nice, [/break is, the indoor unit (C
>, (D) is carried out in the same manner as b, and 1 day l in the room
The lubricating oil accumulated in (C) and (r-1) will be reliably recovered. Therefore, the lack of lubricating oil in the compression 451 ('I) caused by the oil stagnation can be reliably resolved.

In the above embodiment, the case where the aperture degree: A adjustment jt was constructed with an electric expansion valve was explained, but in addition, as shown in FIG. (26) or t shown in the same figure (b). J: Sea urchin These are connected in parallel using two phases and the throttle opening is adjusted in two stages, or J as shown in the same figure (c), Sea urchin These are expansion valves with fixed opening (27) If these are connected in parallel, it is sufficient to use the on-off valve (26) to set the throttle control valve to H'+.

In addition, in the above embodiment, the total loss of the refrigerant in the event of a lubricant shortage in compression (1) was made to flow sequentially to one predetermined indoor unit. It may be possible to distribute the refrigerant sequentially, or it may be possible to distribute the refrigerant to different amounts while not distributing the refrigerant to all rooms.
:! 'C, fiB indoors] to chive 1 (this 1 (] °C) Even if you try to avoid circulating a lot of refrigerant, J, The control of increasing the refrigerant passage area of the pond unit and decreasing the refrigerant flow passage area of the pond unit is changed to 10 for a predetermined time one after another for the Australian unit,
Just make sure you repeat this.

4.Furthermore, in the embodiment described in -F, the oil shortage detection means (20 tons was constructed by detecting a 1! pile in a low capacity operating state of 1 f 1 m), but it is not suitable for detecting the oil level of lubricating oil, etc. Of course, the lubricating oil for the Et compressor is undefined a,
For Y, the compressor is not limited to the highest capacity, but also has a high capacity (e.g. λ, 80-
・You only need to drive 1 knot at 90% capacity).

(Effects of the invention) As explained above, the so-called "Mal 1" according to the present invention
According to the air conditioner on the other hand, it was caused by oil puddles for 71 months! The amount of lubricating oil U1 is undefined, and the calibration degree adjustment valve (2) of each unit in each room is used to sequentially adjust the refrigerant passage area in each room 1-ㅅt~ to perform high-capacity compression operation. By gradually distributing more refrigerant from the large unit to some indoor units, the lubricating oil accumulated in each unit 51' is collected in the compressor, and the oil sump is removed. It is possible to reliably eliminate the lack of lubricating oil caused by 18B-shrinking, and it can effectively contribute to improving the quality of the oil.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the configuration of the present invention, Figs. 2 to 4 show embodiments of the invention, Fig. 2 is a refrigerant piping system diagram, and Fig. 3 is a flow chart showing the construction of the control circuit. 4(a) to 4(a) to 4(c) are diagrams each showing a modification of the aperture adjustment valve. (Δ)...Off-campus unit, (B), (C), <D)
...Indoor unit, (1)...Compressor, (3)...
Outdoor heat exchanger, (7)... Indoor heat exchanger, (8)...
- Electric + H type expansion valve (level adjustment valve), (20)...oil shortage detection means, (21)...control means. Patent R
Hiro °・J 2.・

Claims (1)

[Claims] (1) A throttle that adjusts the degree of restriction of the indoor heat exchanger (7) and refrigerant passage area, respectively, for one outdoor unit (A) containing a built-in compressor (1) and an outdoor heat exchanger (3). Multiple indoor units (B) with built-in temperature adjustment valves (8)
), (C), and (D) connected in parallel, an oil shortage detection means (20) for detecting a lack of lubricating oil in the compressor (1) of the outdoor unit (A); In response to the output of the shortage detection means (20), the compressor (1) is operated at high capacity, and the indoor unit (B) which is in operation is
) to (D), some indoor unit aperture adjustment valves (
8) An air conditioner characterized by comprising a control means (21) that sequentially repeats controlling the throttle control valve (8) of another indoor unit in the opening direction and in the closing direction at predetermined time intervals. Device.