JPH04113914A - Air conditioning equipment for running vehicles - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an evaporator, a heat exchanger arranged downstream of the blower air stream, an air passageway having an air outflow opening at its end for a central nozzle; and two bypass flapper valves (cold air flapper valve and hot air flapper valve) respectively attached to the bypass openings (cold air opening and hot air opening), and the air passage is connected to the heat exchanger via the cold air opening on the one hand. A vehicle, in particular a passenger car, which is connected in the flow direction to the front air chamber and, on the other hand, via a warm air flapper valve to the rear air chamber of the heat exchanger, in each case viewed in the flow direction, said bypass flapper valve being connected to a regulating drive. Regarding air conditioning equipment.

[Prior art] This type of known air conditioning equipment (Magazine ATZ, Auto
m.

Bill Technische Zeitschrif
T, Nr, 9/1987) reprint (W, Frank,
Co-authored by H.-D.Oess, “Comfortable air in passenger cars”
(Mehr Klimakomfort im Per
In the case of the "Sonenwagen", page 4, FIG. 2), conditioned air is introduced in a so-called reheat operation through a so-called central nozzle arranged on the dash board in the central plane of the passenger compartment of a regular vehicle. In the case of reheat operation, the sucked air is first cooled and thus dehumidified by an evaporator and then heated to the desired temperature in a heat exchanger. The amount of air introduced into the passenger compartment is regulated by a shutoff flapper valve located at the air outlet opening of the central nozzle. The shut-off flapper valve increases the air flow (or slightly increases it) depending on its opening degree.

In the "Maximum Cooling" mode of operation, cold air is additionally drawn from the space behind the evaporator or in front of the heat exchanger via a cold air flapper valve, also called a draft flapper valve, into the passenger compartment via an air duct. be introduced. On the other hand, in heating operation, the air outflow through the central nozzle is
Is the air too cold (by design) (about 5°C or less)?
Or it is very hot (over 40 degrees Celsius) and is shut off.

Another air conditioning system known from the above document (see page 5, Figure 5)
In this case, there is no hot air flapper valve, and the cold air flapper valve has the function of an air mixing flapper valve, and this flapper valve allows the hot air flowing into the air passage from the hot air opening to reach the desired air temperature. It is mixed with a lot of cold air. By means of a shut-off flapper valve in the air outlet opening to the central nozzle, the desired air volume can be adjusted steplessly by means of the size of the throttle. In this air conditioner, the throttling of the mixed air at the air outlet opening to the central nozzle creates different pressure states in the air conditioning box, which can lead to backflow, e.g. cold air being directed towards the back of the heat exchanger. This causes undesired cold air to escape through the air outlet openings for the defrost, side and footwell nozzles located behind the heat exchanger.

This can only be avoided by auxiliary non-return flapper valves on the cold and hot air openings.

OBJECT OF THE INVENTION The object of the invention is to improve an air conditioning installation of the type mentioned at the outset in such a way that the temperature regulation and mixing of the air exiting from the central nozzle can be done with very little structural outlay. There is a particular thing.

[Means for Solving the Problem] According to the invention, this object is provided in an air conditioning installation of the type mentioned at the outset, in which the air outlet opening of the central nozzle does not have a flapper valve, and the control unit controls the flow of air exiting from the central nozzle. A characteristic curve giving the relationship between the air quantity and air temperature and the bypass flapper valve opening is stored, and the control unit supplies the regulating drive with the characteristic curve of the bypass flapper valve for a preset air quantity and air temperature. This is achieved by providing an adjustment amount that causes the opening degree.

[Effect of the invention] Based on the present invention (in the case of air conditioning equipment, the principle of temperature adjustment using an air mixing flapper valve and flow rate adjustment using a cutoff flapper valve, which are used in general air conditioning equipment, is abandoned, and instead, each The bypass openings (hot air opening and cold air opening) are individually throttled.

Since no further shutoff flapper valve is downstream of the flapper valve for the bypass opening in the air flow direction, only one flow occurs in the direction of the passenger compartment in all operating modes. A non-return flapper valve as in the known air conditioners mentioned above is not required. The regulating drive for the bypass flapper valve is controlled indefinitely. A negative pressure element or a stepper motor with a feedback potentiometer is used as the adjusting drive.

An advantage of the air conditioner according to the invention is also that the bypass flapper valve is far away from the central nozzle, so noise can be reduced.

When it is desired to separately adjust the air conditioning for the driver and passenger side in the passenger compartment (separate left/right system), individual bypass flapper valves for two separate central nozzles, i.e. a total of four bypasses, are required. A flapper valve must be provided. In the case of the above-mentioned known air conditioning equipment, a total of two air mixing flapper valves, four non-return flapper valves, and two cutoff flapper valves for flow rate control were required in the case of this left-right separation system. . In the case of the air conditioning system according to the invention, therefore, a significant cost reduction is achieved with the same comfort.

An advantageous embodiment of the air conditioning installation according to the invention is defined in claim 2.
It is described in.

[Embodiments] The present invention will be described in detail below with reference to embodiments shown in the drawings.

The air-conditioning system of a motor vehicle, which is shown in a schematic cross-section in FIG.

The above-mentioned components are arranged in the so-called air-conditioning box 14 in the order described above, viewed in the flow direction. The air conditioning box 14, whose air distributor 13 is in direct contact with the passenger compartment 20 of the vehicle, has an air outlet opening (not shown here). This air outlet opening allows air to flow into various locations in the passenger compartment 20 via the defrosting nozzle, side nozzle and foot nozzle. A first intake opening 15, typically equipped with a filter, introduces fresh air into the air conditioning box 14;
Indoor air is sucked in from the passenger compartment 20 via the second suction opening 16 . The two suction openings 15, 16 are alternately closed or opened by the air flapper valve 17. A separate air passage 18 is provided in the air conditioning box 1
4 extends above the heat exchanger 12 and air distributor 13 to the passenger compartment 20, where it opens into the air conditioning box 19. A central nozzle 21, which is integrally provided on the dash board 20 of the passenger compartment 20, is installed in the air outflow opening 19. The air passage 18 is connected to the space 141 of the air conditioning box 14 between the evaporator 11 and the heat exchanger 12 through the cold air opening 22 and to the air distributor 13 through the hot air opening 23. . Each of the two bypass openings 22, 23 can be closed by a bypass flapper valve 24, 25. These bypass flapper valves 2
4.25 can be driven steplessly by the central nozzle 26.27. Both regulating drives 26.27 are connected to the control unit 2, which is connected on the input side to the setpoint value transmitter 29.30.
8 is connected.

One target value transmitter 29 is used to preset the air temperature of the air flowing into the passenger compartment 20 via the central nozzle 21, and the other target value transmitter 30 is used to preset the amount of air. . The target value transmitter 29.30 is, for example, O
It is formed as a potentiometer with an adjustment range of ~5■. In this case, each upper limit value corresponds to a maximum air temperature or air amount. The control unit 28 includes:
Characteristics giving the relationship between the amount and temperature of the air exiting the central nozzle 21 and the opening degree of the bypass flapper valve 24,25 are stored. In that case, the control unit 28
This is applied to the regulating drive 26,27 and the setpoint value transmitter 29.
30 operates to provide a control variable that produces an opening given by the characteristic curve of the bypass flapper valve 24.25 for a preset air quantity and air temperature.

An example of the characteristic curve stored in the control unit 28 is the second
It is shown diagrammatically in the figure. The characteristic curve shown by the dashed line for the hot air flapper valve 25 is 5IJW=UM/Umax
The characteristic curve given by -IT (1) and shown as a solid line for the cold air flapper valve 24 is given by UK=LIM-tJW (2). In that case, UW and UK are the control unit 28
The hot air flapper valve 25 and the cold air flapper valve 24
is the regulating voltage applied to the regulating drive 27,26 of. UT is the air temperature T preset by the target value transmitter 29.
This is the adjustment voltage within the adjustment range corresponding to . UM is the adjustment voltage within the same adjustment range corresponding to the air IM preset by the target value transmitter 30, and Umax is:
Regulating voltage for the regulating drive 26.27 for moving the bypass flapper valve 24.25 into the fully open position, in which the entire cross-sectional area of the cold air opening 22 and the hot air opening 23 is opened. For example, a voltage of UM = 2V is given by the target value transmitter 30 (this corresponds to the intermediate air amount in the adjustment range of 5V), and a voltage of UT = 4V is given by the target value transmitter 29 (this corresponds to 5V). (equivalent to the upper temperature in the adjustment range of (2)), and if the maximum adjustment voltage LImax for fully opening the bypass flapper valve 24, 25 is 5 based on the above equations (1) and (2), Fig. 2 In a, b
A characteristic curve of the control unit 28 shown in is given.

If the voltage UT=4V, the control unit 28 thereby connects the regulating voltage UW=1.6 V to the regulating drive 27 for the hot-air flapper valve 25 and the regulating voltage UK=1.6 V to the regulating drive 26 for the cold-air flapper valve 24. Supply 0.4V. Both regulated voltages are characteristic curves in Figure 2! ! a, b
It is indicated by two small circles above it. Adjustment amount UW, L
Corresponding to IK, the hot air flapper valve 25 is somewhat smaller (open) than the half air flow cross section of the hot air opening 23, and the cold air opening 24 throttles the cold air opening 22 to a very large extent.

The total amount of air flowing through the two bypass openings 22.23 of the central nozzle 21 corresponds to the value given by the setpoint value transmitter 3o. For example, if the voltage is UT=2
V, the regulating voltage UW of the regulating drive 27 for the hot air flapper valve 25 drops to 0.8v, and the regulating voltage UK of the regulating voltage 26 of the regulating drive 26 of the cold air flapper valve 24 drops to 1.2v. rise to Correspondingly warm air opening 23
is narrowed down, and the cold air opening 22 is further opened. If the setpoint value transmitter 3o is not adjusted and remains constant for the desired air quantity, i.e. UM=2V, both air flows through the bypass opening 22.23 into the passenger compartment 20 through the central nozzle 21. The total amount of air consisting of the flow is constant.

[Brief explanation of the drawing]

Figure 1 is a schematic cross-sectional view of the air conditioning system for a passenger car, and Figure 2 is a schematic cross-sectional view of the air conditioning system for a passenger car.
It is a characteristic diagram of the control unit of the air conditioning equipment in a figure. DESCRIPTION OF SYMBOLS 11... Evaporator, 12... Heat exchanger, 13... Air distributor, 18... Air passage, 9... Air flow 8 opening, 20... Passenger compartment, 1... Central nozzle, 22...
Cold air opening, 3... Warm air opening, 4.25... Bypass flapper valve, 8... Control unit.

Claims (1)

[Scope of Claims] (1) An evaporator, a heat exchanger located downstream thereof in the blower airflow, an air passage terminating with an air outlet opening to the central nozzle, and a bypass opening (cold air opening and hot air opening); two bypass flapper valves (a cold air flapper valve and a hot air flapper valve) respectively attached to the air openings), the air passages being connected to the air chamber in front of the heat exchanger via the cold air openings on the one hand and to the air chamber in front of the heat exchanger on the other hand. In air conditioning systems for vehicles, in particular passenger cars, the central nozzle (21 ) does not have a flapper valve, and the control unit (28) controls the central nozzle (2
1) Air volume (M) and air temperature (T) of air exiting from
The control unit (28) stores a characteristic curve giving the relationship between the opening degree of the bypass flapper valve and
6, 27), bypass flapper valves (24, 2) for preset air volume (UM) and air temperature (UT)
5) Adjustment amount (
An air conditioning system for a traveling vehicle characterized by providing air conditioning (UK, UW). (2) The regulating drives (26, 27) for the bypass flapper valves (24, 25) have the same regulating voltage range, and the characteristics for the hot air flapper valve (25) are UW=UM/Umax・UT (1) and the characteristic for the cold air flapper valve 24 is given by UK = UM - UW (2), where UK and UW are the regulating drives of the cold air flapper valve (24) and the hot air flapper valve (25). (26, 27), where UM and UT are the preset air volume (M
) and the air temperature (T), and Umax is the adjustment voltage within the adjustment range corresponding to the air temperature (T), and Umax is the bypass flapper valve ( 24. The air conditioning installation according to claim 1, characterized in that it is a regulating voltage for a regulating drive for moving the air conditioners 24, 25).