JPH0584242B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides an inside air temperature detector, an outside air temperature detector,
An air conditioning system for buses that selects one of the air conditioning modes consisting of at least a cooling mode and a heating mode based on the signal generated by the desired temperature setting device, and controls the operation and stopping of air conditioning equipment according to the selected air conditioning mode. Regarding a control device.

[Conventional technology]

In conventional auto air conditioners for buses, the auto controller calculates the air conditioning heat load from the inside air temperature sensor, outside air temperature sensor, and desired temperature setting device, and automatically selects the required cooling or heating capacity from among several modes. It is controlled so that the internal air temperature and the desired temperature match. Bus vehicles have a large air conditioning load, so the cooling side is equipped with a sub-engine to drive the compressor, and the heating side is equipped with a preheater as a heat source, and the sub-engine and preheater are automatically started and stopped as necessary. It was on.

[Problem that the invention seeks to solve]

In this conventional method, the air conditioning heat load is simply calculated using the two detectors and the desired temperature setting device. ℃, when the internal air temperature is stable at the desired temperature of 28℃, even if the air conditioning heat load is a heating load, the air conditioning heat load may temporarily become a cooling load and the sub-engine may be operated. Ivy. Also, for the same reason, operating the preheater in the summer not only feels strange, but also causes a worsening of the feeling due to cold air blowing out in the winter and hot air blowing out in the summer, and also increases fuel efficiency. It was also undesirable.

In view of the above-mentioned problems, the present invention eliminates the operational discomfort and prevents deterioration of the feeling by not operating the sub-engine or the preheater when it is not necessary.

[Means for solving problems]

The present invention limits the cooling or heating capacity generated by the outside air temperature detected by the outside air temperature detector, so that the sub-engine is not operated when the temperature is below the first predetermined temperature and it is determined that it is winter. This prevents the preheater from being operated when the temperature is higher than the predetermined temperature in step 2 and it is determined that it is summer.

〔Example〕

FIG. 1 shows a system block diagram of the embodiment.
1 is an inside air temperature detector that detects the temperature inside the vehicle;
2 is an outside air temperature detector that detects the temperature of outside air; 3 is a desired temperature setting device that sets the desired inside air temperature; 4
is a sub-engine that drives a refrigerant compressor (compressor) and a blower; 5 is a preheater that serves as a heat source during heating; 6 is a motor that drives the blower during heating and blowing; 7 is for cooling, blowing, and heating. An air outlet switching actuator 8 switches the air outlet to the ceiling or floor depending on the situation, and 8 calculates the air conditioning heat load based on the input from the input elements 1, 2, and 3, and output elements 4, 5, 6, and 8 to obtain the necessary cooling or heating capacity. This is a control device that controls 7.

The operation of the embodiment will be described below using the flowchart shown in FIG. 2, the operation mode table shown in FIG. 3, and the control mode range table according to outside air temperature shown in FIG. 4. When the device starts operating and the power is turned on, the control device 8 inputs the signals from the input elements 1 to 3, and also inputs the signals from the input elements 1 to 3, and changes the outside temperature as shown in the control mode range table based on the outside air temperature in FIG. 4. Determine the control mode range.

Considering the case where the outside air temperature is, for example, less than 5°C (corresponding to the first predetermined temperature of the present invention),
The control mode range is determined to be, for example, M6 to M12. Next, the air conditioning load is calculated using three inputs: the inside air temperature, desired temperature, and outside air temperature. If the current indoor air temperature is 28℃, and the desired temperature is 28℃, and the mode selected from the air conditioning heat load is, for example, M10, then M10
is within the restricted control mode range M6 to M12, so operation is performed in M10.

If you change the desired temperature from 28℃ to 24℃ from this state, the air conditioning heat load becomes a cooling load, and if the mode selected from the air conditioning heat load becomes M4, for example, the limited control mode range is within M6 to M12. Therefore, it is not operated in M4, and the driving mode is M.
It is modified to M6, which is the closest to M4 among M6 to M12, and thus when the outside temperature is less than 5℃,
The sub-engine is not operated due to a change in the desired temperature.

Generally, in bus vehicles, the air conditioner unit is installed under the floor behind the front wheels of the vehicle, so when the outside temperature is below freezing, snow and water kicked up by the front wheels can freeze on the air conditioner unit. When the sub-engine is started, it drives frozen items such as the V-belt, condenser fan, magnetic clutch, and shaft, which can lead to serious malfunctions such as damage to functional items.

Furthermore, when starting an engine at low temperatures, it is ideal to warm it up without applying any load, but in the case of air conditioners for buses that use sub-engines, as is well known, the compressor, condenser fan, and passenger compartment Since the blower fan etc. are directly connected to the sub-engine, the sub-engine will be operated under load from the time it is started. This results in lubrication with engine oil, which has become more viscous due to the low temperature, which accelerates the wear of piston rings, bores, etc.

However, as in the present invention, by limiting the range of control modes to other air conditioning modes other than cooling mode in winter, it not only solves the problem of feeling that cold air comes out in winter; By operating the sub-engine when the air conditioner system is frozen, it is possible to prevent serious malfunctions such as damage to various functional parts. Furthermore, it is possible to prevent noise and vibration caused by driving the sub-engine and operating each functional part. It is possible to prevent this from occurring and deterioration of fuel efficiency.

On the other hand, it is conceivable that the heating mode may be set in the summer as well as in the winter. Passenger cars can be heated using only the temperature of the cooling water from the driving engine, but in buses, heating capacity is insufficient if the cooling water temperature is only generated by exhaust heat from the driving engine, so a preheater is activated. It is necessary to raise the temperature of the cooling water by Therefore, the problem arises that fuel consumption deteriorates due to the activation of the preheater, but since the present invention restricts the air conditioning mode to other modes than the heating mode in the summer, warm air is blown out in the summer. This not only solves the problem of feeling, but also solves the problem peculiar to air conditioners for buses, such as deterioration of fuel efficiency due to the use of a preheater as described above.

In the case of other outside temperature conditions in FIG. 4, the control mode range is limited, and the outside temperature is 5.
Using the same concept as when the temperature is below ℃, unnecessary equipment will not be operated when the desired temperature is changed. Furthermore, as shown in Figure 4, the outside temperature is 25℃.
corresponds to the second predetermined temperature of the present invention. Similarly, even if there is an operational error in setting the desired temperature, unnecessary equipment can be prevented from being operated using the same concept as when changing the desired temperature. Note that in this embodiment, since the outside air temperature detected by the outside air temperature detector provided for calculating the air conditioning heat load is used for the control of the present invention, there is no need to provide a new detector.

[Effects of the Invention] As explained above, the present invention limits the selection range of air conditioning modes according to the outside temperature, thereby preventing erroneous operation of the desired temperature setting device and false detection of the inside air temperature detector. This prevents the air conditioning equipment from being operated undesirably.

In addition, in bus vehicles, cooling is performed by driving a sub-engine dedicated to cooling, and heating is performed by raising the temperature of the cooling water of the main engine for driving by operating a preheater. Therefore, by limiting the control range so that the air conditioning mode is set to an air conditioning mode other than the heating mode in the summer, or to an air conditioning mode other than the cooling mode in the winter, it is possible to operate the preheater in the summer. This eliminates the risk of deterioration in fuel efficiency, and also eliminates the need to switch to cooling mode and drive the sub-engine in winter, which prevents serious malfunctions such as damage to functional parts caused by operating the sub-engine when the air conditioner freezes. Furthermore, it is possible to prevent the generation of noise and vibration and the deterioration of fuel efficiency due to driving the sub-engine and operating the functional parts.

[Brief explanation of drawings]

Fig. 1 is a system block diagram showing an embodiment of the present invention, Fig. 2 is a flowchart showing a control program of the control device shown in Fig. 1, and Fig. 3 is for explaining the air conditioning mode of the device of the embodiment. FIG. 4 is a control mode range table for explaining air conditioning mode restrictions. 1... Inside air temperature detector, 2... Outside air temperature detector, 3... Desired temperature setting device, 4... Sub engine, 5... Preheater, 6... Blower motor, 7...
Air outlet switching actuator, 8...control device.

Claims (1)

[Scope of Claims] 1. An inside temperature detector that detects the temperature inside the vehicle interior, an outside temperature detector that detects the outside temperature, a desired temperature setting device that sets the desired temperature inside the vehicle interior, and a sub-engine dedicated to cooling. a cooling unit that drives a refrigerant compressor to cool the interior of the vehicle, a heating unit that operates a preheater to raise the temperature of cooling water for the main engine for driving, and heats the interior of the vehicle with this cooling water; It has at least two air conditioning modes, a cooling mode by the heating unit and a heating mode by the heating unit, and is based on the detected values and set values of the inside temperature detector, the outside temperature detector, and the desired temperature setting device. an air conditioning control means for controlling operation and stop of the sub-engine and the preheater, and selecting an air conditioning mode other than the cooling mode when the outside temperature detected by the outside temperature detector is below a first predetermined temperature. and an air conditioning mode selected by the air conditioning control means such that an air conditioning mode other than the heating mode is selected when the outside air temperature is at least a second predetermined temperature that is higher than the first predetermined temperature. An air conditioning control device for a bus vehicle, comprising: an air conditioning mode limiting means for limiting;