JPH10147140A - Heat pump type air-conditioning device for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat-pump type air-conditioning device for an automobile, in which heating of coolant by a subheat-exchanger can be selected so that cooling and heating operation can be carried out without unnecessarily heating coolant, and various heating operations which are finely controlled can be carried out. SOLUTION: In a heat-pump type air-conditioning device for an automobile, in which coolant is heated by a subheaet-exchanger 30 with the use of heat from engine cooling water so as to use coolant changed through isoentropy in order to exhibit a high heating function, coolant adapted to be introduced into the subheat-exchanger 30 flows bypassing this subheat-exchanger through a bypass passage 31 in which a shut-off valve 32 is incorporated. Thereby it is possible to carry out cooling and heating with the use of this subheat- exchanger 30 without unnecessary heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump type air conditioner for cooling and heating the interior of a vehicle using engine cooling water and a refrigerant, and more particularly to a dual type heat pump type vehicle in which operation during heating can be finely controlled. The present invention relates to an air conditioner for use.

[0002]

2. Description of the Related Art A dual-type heat-pump type air conditioner for automobiles incorporated in a luxury car, a one-box car having a large cabin space, or the like, has a condition in which warm air is blown out at the same time as the start of a heating operation. Not
It lacks the so-called immediate warming property, and the heating performance tends to be insufficient.

[0003] Therefore, in order to solve such a problem, the applicant of the present application heats the refrigerant by using the heat of the engine cooling water, uses the refrigerant having an isentropic change, and exhibits higher heating performance. Proposed a heat pump type air conditioner for automobiles (Japanese Patent Application No. 7-271,621).
No.).

In this vehicle air conditioner, as shown in FIG. 3, a refrigerant flowing out of a second heat exchanger 22 of a rear unit 20 flows into a sub heat exchanger 30, and the sub heat exchanger 30 The refrigerant is heated by the cooling water.

In FIG. 3, "Wm" is a main hot water circuit, and "Wm"
"s" is a sub hot water circuit, "11a, 11b" is a hot water cock, "3" is a first condenser, "10" is a front unit, "11" is a heater core, "12" is a first heat exchanger, "21". Is a second capacitor.

[0006] The engine cooling water, which could not be used immediately for heating even if heat exchanged with air because of low temperature in the past, is exchanged with the extremely low temperature refrigerant in the sub heat exchanger 30 to provide engine cooling water. After effectively taking the heat held by the refrigerant into the refrigerant, it is returned to the compressor 2,
Since this is pressurized again, the refrigerant discharged from the compressor 1 can be supplied to the second condenser 21 as a high-temperature isenthalpy-changed refrigerant. The exchanged air has a higher temperature, exhibits high heating performance, and has an improved immediate warming property.

[0007]

However, in the air conditioner for an automobile configured as described above, the heating of the refrigerant by the sub heat exchanger 30 is inevitably performed in the heating operation. For this reason, excellent heating performance is initiated in the early stage of the heating operation. However, in the heating operation stable period, there is a possibility that the calorie becomes excessive or the discharge pressure of the compressor becomes high.

However, the hot water cock 11b may be closed to prevent the engine cooling water from flowing into the sub heat exchanger 30, but even in this case, the high temperature Is in a sealed state,
If the refrigerant circulates here, it will be heated by the engine cooling water, and unnecessary heat will be added to the refrigerant. In such a state, after a while, the refrigerant itself takes away the heat of the engine cooling water present in the sub heat exchanger 30 and becomes a predetermined operating state. It takes a relatively long time, and there is a possibility that an excessive heating state will continue for a while even after the heating operation is stabilized.

During the cooling operation, the hot water cock 11b
Is closed, the heat of the engine coolant flowing through the main hot water circuit Wm enters the sub heat exchanger 30,
There is a possibility that the refrigerant flowing here will be heated unnecessarily,
This may impair the cooling performance.

The present invention has been made in view of such problems of the prior art, and makes it possible to select the heating of a refrigerant by a sub heat exchanger, thereby performing a cooling / heating operation without unnecessarily heating the refrigerant. It is an object of the present invention to provide a heat pump type air conditioner for a vehicle, which can perform various heating operations that can be controlled in a heating mode.

[0011]

To achieve the above object, according to the present invention, a heater core through which engine cooling water flowing through a main hot water circuit is guided, a compressor, a first condenser and A first unit in which a first heat exchanger constituting a cooling cycle together with a first expansion valve is arranged; and the first heat exchanger so that a part of the refrigerant in the cooling cycle is introduced using an on-off valve. A second unit in which a second condenser and a second heat exchanger are connected in parallel with each other, and a second expansion valve provided on the inlet side of the second heat exchanger; A sub heat exchanger is provided outside the second unit, and the refrigerant flowing out of the second heat exchanger is configured to be returned to the compressor through the sub heat exchanger. Main hot water circuit In the heat pump type air conditioner for a vehicle in which a part of the engine cooling water to be introduced is guided by a sub hot water circuit and the refrigerant is heated by the engine cooling water by the sub heat exchanger, the refrigerant is sub-heated. A bypass circuit for bypassing the exchanger is provided, and an opening / closing valve for opening and closing the bypass circuit is provided in the bypass circuit.

In this way, if the opening / closing valve of the bypass circuit is closed, the refrigerant can be heated by the sub heat exchanger. If the valve is opened, heating of the refrigerant can be avoided. By only selecting opening and closing, it is possible to perform cooling and heating operation without unnecessary heating of the refrigerant,
Also, by opening the on-off valve, it is possible to avoid a situation in which the discharge pressure of the compressor abnormally rises.

According to the second aspect of the present invention, the open / close operating valve detects at least one of the pressure or temperature of the return refrigerant or the discharge refrigerant of the compressor or the degree of superheat of the return refrigerant, and the detected value is used as the value. It is characterized in that it is closed when it exceeds a predetermined value.

According to this configuration, the opening / closing operation valve is automatically closed in accordance with the heat load during the cooling / heating operation, so that the heating of the refrigerant by the sub heat exchanger can be automatically avoided. The present invention described in claim 3 is characterized in that the open / close operation valve and the hot water cock provided in the main hot water circuit and the sub hot water circuit are selectively opened and closed.

[0015] In this manner, by selectively opening and closing the open / close operation valve and the hot water cock during the heating operation, various modes of the heating operation can be performed, and a more detailed heating operation can be performed.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention, and FIG. 2 is a schematic perspective view showing a sub heat exchanger incorporated in the embodiment. In these drawings, the same members as those in FIG. Are attached. In the figure, white arrows indicate the flow of air, solid arrows indicate the flow of the refrigerant,
The dashed arrows indicate the flow of the engine cooling water.

As shown in FIG. 1, in the present embodiment, a first air-conditioning system for air-conditioned inside and outside air selectively taken in from an intake unit (not shown) and blowing the air to a front seat is provided.
This is a so-called dual air conditioner having a front unit 10 which is a unit and a rear unit 20 which is a second unit for air-conditioning the inside air and blowing the air to a rear seat.

The front unit 10 includes an intake unit, an intake door and a blower motor (neither of which is shown) in an air flow path 10f formed by a casing in order from the upstream side in the air flow direction indicated by a white arrow. First heat exchanger 12, air mix door (not shown)
And a heater core 11, and an air outlet (not shown) into the vehicle interior is provided downstream of the air flow direction.

The front unit 10 has an air mix door (not shown) at the front of the heater core 11.
To adjust the ratio of hot air to cold air to produce air at a predetermined temperature downstream of the heater core 11 or to prevent air from flowing through the heater core 11.

The heater core 11 has a main hot water circuit W through which engine cooling water flowing out of the engine 2 flows.
m, and engine cooling water is introduced by opening and closing the hot water cock 11a of the hot water circuit Wm.

On the other hand, in the rear unit 20, a second heat exchanger 22 and a second condenser 21 are arranged in an air passage 20f formed by a casing in order from the upstream side in the air flow direction indicated by a white arrow. I have.

The rear unit 20 also has an air mix door (not shown) on the front surface of the second condenser 21.
And the ratio of hot air to cold air is adjusted to adjust the second condenser 2
Air at a predetermined temperature in the downstream area of 1
The structure is such that air does not flow through the condenser 21.

In the present embodiment, the first heat exchanger 12, the second condenser 21, and the second heat exchanger 22 provided in the front unit 10 and the rear unit 20, respectively, are used as constituent parts. A first cooling cycle in which the condenser 3, the liquid tank 4a, the first opening / closing valve V1, the first expansion valve 5a, and the first heat exchanger 12 are connected by a refrigerant pipe, and a parallel to the first heat exchanger 12 Specifically, the second cooling cycle in which the second on-off valve V2, the second condenser 21, the liquid tank 4b, the second expansion valve 5b, the second heat exchanger 22, and the sub heat exchanger 30 are connected by refrigerant pipes. Have.

Further, a bypass circuit 3B is provided to allow the refrigerant discharged from the compressor 1 to bypass the first condenser 3 so that the cooling operation and the heating operation can be realized in the same cycle. The switching between the first condenser 3 and the bypass circuit 3B is performed by the four-way valve 7, and the refrigerant discharged from the compressor is in the heating operation.
It is guided to the bypass circuit 3B and to the first capacitor 3 during the cooling operation.

Further, the first cooling cycle and the second
Is switched by a combination of the opening and closing operations of the first on-off valve V1 and the second on-off valve V2.

When the refrigerant from the compressor 1 is switched to the first condenser 3 and the bypass circuit 3B, the reason why the four-way valve 7 is used here is that although there are only three passages, This is because a return circuit m (a portion shown by a broken line) can be provided for temporarily returning a large amount of refrigerant accumulated in the first condenser 3 to the compressor 1 at the time of starting heating.

The sub heat exchanger 30 has a shape as shown in FIG. 2, for example, and is provided outside the air passages 10f, 20f of the front unit 10 and the rear unit 20. In the sub heat exchanger 30, engine cooling water for exchanging heat with the refrigerant flowing inside is provided with the main hot water circuit W.
m, through the sub-hot water circuit Ws, and is introduced by opening the hot water cock 11b. In the sub heat exchanger 30, since the refrigerant flowing through the sub heat exchanger 30 is heated by the engine cooling water, a high heating performance is exhibited by the refrigerant whose isenthalpy has changed in the compressor 1.

Particularly, in the present embodiment, a bypass circuit 31 is provided to allow the refrigerant introduced into the sub heat exchanger 30 to flow by bypassing the sub heat exchanger 30.
The bypass circuit 31 is provided with an opening / closing valve 32 for opening and closing the circuit 31.

The bypass circuit 31 and the open / close operating valve 32
The purpose of the present invention is to prevent an excessive amount of heat during the stable period of the heating operation and to prevent the abnormal discharge pressure of the compressor from increasing.

The control of the opening / closing valve 32 includes, for example, the temperature and pressure of the refrigerant returning to the compressor 1, the temperature and pressure of the refrigerant discharged from the compressor 1, and in some cases, the degree of superheat of the refrigerant returning to the compressor 1. A detecting member (not shown) for detecting is provided near the inlet / outlet of the compressor 1 or near the outlet of the first heat exchanger 12 or the second heat exchanger 22 functioning as an evaporator. When one of them detects a predetermined value or more, a signal from the detection member is input to a control unit (not shown),
The operation is performed by operating an actuator (not shown) for operating the opening / closing operation valve 32 in response to a signal from the control unit and opening the opening / closing operation valve 32.

Here, the detection of the temperature, pressure, degree of superheat and the like of the refrigerant returning to the compressor 1 means that if these are high, the heat load in the cooling cycle is large and the amount of heat is excessive. It is.

Therefore, during the heating operation, in order to avoid such a situation, the opening / closing operation valve 32 is opened so that the refrigerant bypasses the sub heat exchanger 30 and returns to the compressor. The heat of the high-temperature engine cooling water in 30 is not transmitted to the refrigerant, and the occurrence of an abnormal rise in the discharge pressure of the compressor caused by compressing the heated refrigerant is also prevented.

Next, the overall operation will be described. (1) Initial Heating Operation When heating both front and rear seats, first, the first on-off valve V1 is closed, the second on-off valve V2 is opened, and the four-way valve 7 is switched to set the refrigerant to flow to the bypass circuit 3B. .

When the compressor 1 is operated in this state, the high-temperature and high-pressure refrigerant discharged from the compressor 1
Four-way valve 7 → bypass circuit 3B → liquid tank 4a → second on-off valve V2 → second condenser 21 → liquid tank 4
b, and this refrigerant flows through the second expansion valve 5b → the second heat exchanger 22 → the sub heat exchanger 30 to flow through the compressor 1
Return to.

The hot water cocks 11a and 11b are both opened to allow the engine cooling water having a certain rise in temperature to flow through the heater core 11 when the engine 1 is started, and the engine cooling water to flow through the sub heat exchanger 30. deep.

Thus, in the front unit 10,
Although the first heat exchanger 12 does not function, the intake air is heated to some extent by passing through the heater core 11, and warm air is supplied from the front unit 10 to the room.

On the other hand, in the rear unit 20, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is supplied to the second on-off valve V
2 and enters the second capacitor 21. Here, heat exchange is performed with the air in the vehicle interior, the air is heated and then condensed to become a medium-temperature and high-pressure refrigerant, which is adiabatically expanded by the second expansion valve 5b, becomes a low-pressure refrigerant at a lower temperature, and functions as an evaporator. Enter the exchanger 22. Here, it exchanges heat with the vehicle interior air, cools the air, evaporates, flows as a low-temperature low-pressure refrigerant, and flows to the sub heat exchanger 30.

Accordingly, the air inside the vehicle is first cooled in the second heat exchanger 22 and then cooled in the second condenser 2.
Since it is heated in step 1, the dehumidified warm air can be supplied to the room in the rear unit.

The heating effect of the second condenser 21 is further enhanced by the sub heat exchanger 30. That is, the low-temperature and low-pressure refrigerant flowing through the sub heat exchanger 30 takes in the heat of the outside air and the heat from the engine cooling water in the sub heat exchanger 30, raises the temperature, and returns the refrigerant whose entropy has changed to the compressor 1. Is compressed again, the temperature of the refrigerant discharged from the compressor 1 rises, high heating performance is exhibited, and immediate warming is improved.

That is, the refrigerant returned to the compressor 1 is heated by the air in the second heat exchanger 22 and heated by the engine cooling water in the sub heat exchanger 30, which is a so-called two-stage heating method. The temperature rise of the refrigerant compressed by the compressor 1 is further accelerated. This tendency is amplified as time passes, so that the so-called immediate warming property is improved.

If the temperature of the engine cooling water rises while this operation is continued for a while, the heating capacity of the heater core 11 in the front unit 10 increases, and high-temperature air is blown out. become.

(2) Heating operation stabilization period The temperature of the engine cooling water rises and the front unit 10
In the rear unit 20 as well, when stable air at a high temperature is blown out, the first on-off valve V1 is also opened, and the high-temperature and high-pressure refrigerant discharged from the compressor 1
It also flows into the first heat exchanger 12 of the front unit 10,
The first heat exchanger 12 functions as an evaporator, and dehumidifying and heating is performed also in the front seat.

However, in this embodiment, in the heating operation stable period, various operation modes can be selected by selectively opening and closing the hot water cocks 11a and 11b and the opening / closing operation valve 32 as appropriate. For opening and closing the hot water cocks 11a and 11b and the opening / closing operation valve 32, for example, each valve of a solenoid valve type may be selected and opened / closed by a switch. It may be controlled.

First, the first mode is a hot water cock 11a,
11b are both set to "open" and the open / close operation valve 32 is set to "closed".

With this configuration, the engine coolant whose temperature has risen from the engine 1 flows to the heater core 11 through the main hot water circuit Wm, so that the first heat exchanger 12 functions as an evaporator in the front seat, And heater core 1
The dehumidifying heating in which the air heating by 1 is performed is performed.
On the other hand, in the rear seat, the engine cooling water whose temperature has risen flows to the sub heat exchanger 30 through the sub hot water circuit Ws, so that the refrigerant heated by the sub heat exchanger 30 flows to the second condenser 21, and High heating performance is exhibited.

In the second mode, the hot water cock 11a is "open".
The hot water cock 11b and the opening / closing valve 32 are closed.

In this way, in the front seat, the first heat exchanger 12 functions as an evaporator and the heater core 1
1, the rear seat closes the hot water cock 11b, so that the engine cooling water does not flow into the sub heat exchanger 30 and the high temperature inside the sub heat exchanger 30. The engine cooling water remains sealed. Therefore, when the refrigerant flows through the sub heat exchanger 30, the refrigerant is heated by the engine cooling water. However, the amount of heat gradually decreases due to the flowing refrigerant, and after a predetermined time elapses, the operation shifts to the normal heating operation. That is, even in the full hot operation state, the operation state in which a higher temperature hot air is obtained continues for a while, and thereafter, the operation state gradually becomes the normal high temperature hot air.

In this embodiment, if the operation state changes suddenly from the operation state in which higher temperature hot air is obtained to the operation in which normal high temperature hot air is obtained, a feeling of strangeness may occur depending on the occupant. By gradually changing the operation state in this way, a gentle operation can be performed.

In the third embodiment, the hot water cock 11a is "open", the hot water cock 11b is "closed", the on-off valve 32 is "open", and the refrigerant flowing through the sub heat exchanger 30 is bypassed. 31.

In this way, in the front seat, the first,
Dehumidification heating is performed in the same manner as in the second embodiment, but in the rear seat,
By closing the hot water cock 11b and opening the opening / closing operation valve 32, the refrigerant flows through the bypass circuit 31 irrespective of the high-temperature engine cooling water in the sub heat exchanger 30, so that the refrigerant generated by the engine cooling water Heating is stopped instantaneously and operation is immediately performed with normal hot air. In this aspect, an operation state in which operation in a higher temperature state can be instantaneously stopped can be realized. In particular, in this case, there is an advantage that even when the discharge pressure of the compressor becomes abnormally high, this can be easily avoided.

Since the heating operation is not performed with the hot water cock 11a closed, there is no mode that involves closing the hot water cock 11a.

(3) Cooling operation When cooling the front and rear seats, the first on-off valve V1 and the second
One of a front cooler, a dual cooler, and a rear cooler can be selected according to the combination of the open / close state of the on-off valve V2.

In other words, when cooling only the front seat, the four-way valve 7 is switched to set the refrigerant from the compressor 1 to flow to the first condenser 3, and then the first on-off valve V1 is opened, 2 Close the on-off valve V2. Thereby, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is supplied to the four-way valve 7 → the first condenser 3 → the liquid tank 4a.
→ 1st on-off valve V1 → 1st expansion valve 5a → 1st heat exchanger 12
And return to the compressor 1. Thereby, the first
The heat exchanger 12 functions as an evaporator, and the air introduced into the front unit 10
2, the cooling air is supplied to the front seat.

When used as a dual cooler for cooling both the front and rear seats, the four-way valve 7 is switched to set the refrigerant from the compressor 1 to flow to the first condenser 3, and then to the first opening / closing. The valve V1 and the second on-off valve V2 are both opened. Thereby, the high-temperature and high-pressure refrigerant discharged from the compressor 1 flows through the four-way valve 7 → the first condenser 3 → the liquid tank 4a, and branches there, and a part of the refrigerant flows into the first on-off valve V1 → the first Expansion valve 5a →
It returns to the first heat exchanger 12 and the flow compressor 1. The remaining refrigerant is supplied from the second on-off valve V2 to the second condenser 2
1 → liquid tank 4b → second expansion valve 5b → second heat exchanger 22 → sub heat exchanger 30 and return to compressor 1.

As a result, the first heat exchanger 12 of the front unit 10 functions as an evaporator, and the air introduced into the front unit 10
And the cooling air is supplied to the front seat. In the rear unit 20, the second heat exchanger 22 functions as an evaporator. And rear unit 2
The air taken in at 0 is cooled by the second heat exchanger 22 and cooling air is supplied to the rear seat. Thereby, a dual cooler is realized.

When only the rear seats are to be cooled, the four-way valve 7 is switched to set the refrigerant from the compressor 1 to flow to the first condenser 3, and then the second on-off valve V2 is opened and the first on-off valve V2 is opened. Close the on-off valve V1. Thereby, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is supplied to the four-way valve 7 → the first condenser 3 → the liquid tank 4a → the second on-off valve V2 → the second condenser 21 → the liquid tank 4b → the second expansion valve 5b → the (2) The heat exchanger 22 → the sub heat exchanger 30 flows and returns to the compressor 1.

As a result, the refrigerant does not flow through the first heat exchanger 12 of the front unit 10 and thus does not function as an evaporator.
The heat exchanger 22 functions as an evaporator. As a result, the air taken into the rear unit 20 is
Cooled by the heat exchanger 22, cooling air is supplied only to the rear seats.

The present invention is not limited to the above-described embodiment, but can be variously modified within the scope of the claims. For example, in the above-described embodiment, the sub heat exchanger 30 is provided at a position immediately adjacent to the compressor 1. However, the sub heat exchanger 30 does not necessarily need to be at such a position.
0 may be provided.

[0059]

As described above, according to the first aspect of the present invention, the refrigerant is selectively bypassed to flow through the sub heat exchanger, so that the refrigerant may be unnecessarily heated in some cases. It is possible to perform a desired cooling and heating operation without the need, and it is also possible to avoid a situation in which the discharge pressure of the compressor rises abnormally by opening the on-off valve.

According to the second aspect of the present invention, since the opening / closing valve is automatically closed according to the heat load during the cooling / heating operation, the heating of the refrigerant by the sub heat exchanger can be automatically avoided.

According to the third aspect of the present invention, if the opening / closing operation valve and the hot water cock are selectively opened / closed during the heating operation,
Various modes of heating operation can be performed, and more detailed heating operation can be performed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention.

FIG. 2 is a schematic perspective view showing a sub heat exchanger incorporated in the embodiment.

FIG. 3 is a schematic configuration diagram of a conventional automotive air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Compressor 3 ... 1st condenser 5a ... 1st expansion valve 5b ... 2nd expansion valve 10 ... Front unit (1st unit) 11 ... Heater core 11a 11b ... Hot water cock 12 ... 1st heat Exchanger, 20: rear unit (second unit), 21: second condenser, 22: second heat exchanger, 30: sub heat exchanger, 31: bypass circuit, 32: open / close operating valve, V1, V2: open / close Valve, Wm: Main hot water circuit, Ws: Sub hot water circuit.

Claims (3)

[Claims] A heater core (11) through which engine cooling water flowing through a main hot water circuit (Wm) is introduced, and a compressor.
(1) a first unit (10) in which a first heat exchanger (12) constituting a cooling cycle is arranged together with a first condenser (3) and a first expansion valve (5a); V2), a second condenser (21) and a second heat exchanger (22) connected in parallel with the first heat exchanger (12) so that a part of the refrigerant of the cooling cycle is introduced. And a second expansion valve provided on the inlet side of the second heat exchanger (22).
(5b), and the sub heat exchanger (3) outside the first and second units (10, 20).
0), the refrigerant flowing out of the second heat exchanger (22) is configured to return to the compressor (1) through the sub heat exchanger (30), and the sub heat exchanger ( Three
(0), a part of the engine cooling water flowing through the main hot water circuit (Wm) is configured to be guided by a sub hot water circuit (Ws), and the refrigerant is heated by the engine cooling water by the sub heat exchanger (30). In the heat pump type air conditioner for a vehicle as described above, a bypass circuit (31) for allowing the refrigerant to flow by bypassing the sub heat exchanger (30) is provided, and the bypass circuit (31) is provided in the bypass circuit (31). )
(32) A heat pump type air conditioner for a vehicle, characterized by including (32). 2. The on-off valve (32) detects at least one of a pressure or temperature of a return refrigerant or a discharge refrigerant of the compressor (1) or a degree of superheat of the return refrigerant, and the detected value is a predetermined value. The heat pump type air conditioner for a vehicle according to claim 1, wherein the air conditioner is configured to be closed when the above condition is satisfied. 3. A hot water cock (1) provided in the open / close operating valve (32) and the main hot water circuit (Wm) and the sub hot water circuit (Ws).
2. A heat pump type air conditioner for a vehicle according to claim 1, wherein the opening and closing control of 1a, 11b) is selectively performed.