JPS592968Y2 - Air conditioner control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for an air conditioner used in a vehicle, and more particularly to a control device for an air conditioner for adjusting the temperature inside a vehicle.

Various control devices for air conditioners of the above type have already been proposed.

Conventional devices of this type include a control circuit that generates an electrical signal by comparing the set temperature and the temperature inside the vehicle, and a control circuit that is activated by the electrical signal to control the amount of air passing through the heating heat exchanger. It has a solenoid valve that controls the transmission of working fluid pressure to an actuator that operates the door.

In such conventional devices, there is a delay between when the electric signal is generated by the control circuit and when the door is moved to the desired position, resulting in the temperature inside the vehicle considerably rising or falling beyond the desired set temperature. There was a disadvantage that a hunting phenomenon occurred.

Therefore, in the past, a feedback circuit including a potentiometer was provided to detect the operating position of the actuator or the like and provide a control circuit with a correction signal related to the generation of an electric signal.

However, such feedback circuits have the disadvantage of being expensive.

Therefore, in order to reduce the hunting phenomenon of the vehicle interior temperature relative to the set temperature as much as possible, the working fluid pressure transmitted to the door operating actuator via the solenoid valve that responds to the command electric signal is delayed and Technical measures are conceivable to delay and slow the actuation of the door in such a way that it is achieved gradually.

FIG. 1 is a control device showing an example of this means.

In FIG. 1, 10 is a temperature setting circuit, and 11 is a vehicle interior temperature detection circuit. By applying their respective output signals to a comparator circuit 12, the comparator circuit 12 determines the vehicle interior temperature relative to the set temperature. The difference controls the operation of the electromagnetic valve means 13 for switching the working fluid.

The solenoid valve means 13 has a pair of switching solenoid valves 14.15, each solenoid valve 14.15 being moved to its closed position against a spring 18.19 by the attractive force when the coil 16.17 is energized. It has valve bodies 20 and 21 that move from the open position to the open position.

The valve element 20 operates to open and close communication between an inlet 22 and an outlet 23 connected to a negative pressure source such as an intake manifold of the vehicle, and the valve element 21 operates to open and close communication between an inlet 24 and an outlet 25 connected to an atmospheric source via an air cleaner or the like. It operates to open and close the communication.

When the valve body 20 opens in this manner, operating negative pressure is allowed to be introduced into the passage 27 leading to the actuator 26, and when the valve body 21 opens, the atmosphere is allowed to be introduced into the passage 27.

The circuits 10, 11, and 12 described above may be well-known circuits, and when the temperature inside the vehicle is higher than the set temperature, the coil 17 of the solenoid valve 15 is energized and the valve body 21 is opened, and when the temperature inside the vehicle is lower than the set temperature, the circuit 17 is excited. The coil 16 of the electromagnetic valve 14 is excited and the valve body 20 is opened.

The actuator 26 has a displacement member 30 which is secured by a diaphragm or the like and whose outer periphery is sandwiched between the two bodies 28 and 29, thereby dividing the body into an operating chamber 31 connected to the passage 27 and an atmospheric pressure chamber 32. .

A spring 33 is disposed within the working chamber 31 to bias the displacement portion 30 to the right in the figure.

An operating rod 34 is fixed to the displacement member 30 and extends to the outside via the body 29, and the rod 34 further extends into a ventilation passage 35 through which air is blown via a cooling heat exchanger by a blower drive motor or the like. There is.

The other end of the rod 34 is connected to a door 37 for adjusting the mixing ratio of cold air and warm air, which controls air blowing to a heating heat exchanger 36 disposed in the passage 35.

One end 38 of the door 37 is pivoted at an appropriate location on the exchanger 36 or the passage 35, and the door 37 is rotated in accordance with the actuation of the rod 34 in response to the displacement of the displacement member 30. Controls air blowing through exchanger 36.

As described above, when atmospheric pressure is introduced into the chamber 31 of the actuator 26 by the operation of the solenoid valve means 13, the spring 3
3, the displacement member 30, and therefore the rod 34, moves to the right in the figure, and the door 37 rotates clockwise to reduce the airflow through the heating heat exchanger 36, thereby lowering the temperature inside the vehicle. On the other hand, the chamber 3 is opened by actuation of the solenoid valve means 13.
1, the displacement member 30 and the rod 34 move to the left against the spring 33, and the door 37 rotates counterclockwise to increase the air flow through the heating heat exchanger 36. The function is to raise the temperature inside the vehicle.

Here, the negative pressure or atmospheric pressure introduced into the chamber 31 of the actuator 26 via the electromagnetic valve means 13 is configured such that its transmission is delayed by an orifice 39 provided in the passage 27.

Therefore, after the comparator circuit 12 detects the difference in the cabin temperature with respect to the set temperature and generates a signal for actuating the solenoid valve means 13, the introduction of negative pressure or atmospheric pressure to the chamber 31 is delayed and controlled by the orifice 39. Actuator 2
6 is delayed and its operating speed becomes slow.

Now, for example, if the temperature inside the vehicle is lower than the set temperature and negative pressure is gradually introduced into the chamber 31 of the actuator 26, the temperature inside the vehicle gradually reaches the set temperature by the slow counterclockwise operation of the door 37. When the temperature approaches the set temperature, the coil 16
is de-excited and the valve body 20 returns to the illustrated position.

Since the door 37 operates extremely slowly, the temperature inside the vehicle is prevented from rising excessively due to over-operation, and the temperature is substantially maintained at the set temperature. The negative pressure value introduced into the chamber 31 until now is held.

Therefore, the door 37 is maintained at a desired position, and the temperature inside the vehicle is maintained approximately at the desired set temperature.

If the operating condition of the vehicle changes and the temperature inside the vehicle exceeds the set temperature and rises, for example, the valve body 21 opens in response to a signal from the comparator circuit 12, and the chamber 31 of the actuator 26 opens.
atmospheric pressure is gradually introduced.

The door 37 is therefore gradually introduced clockwise.

Therefore, the door 37 is gradually operated clockwise, and the temperature inside the vehicle approaches the set temperature. When the temperature reaches the set temperature, the coil 17 is de-energized and the valve body 21 returns to the closed position shown in the figure.

Due to the slow operation of the door, the temperature inside the vehicle does not drop excessively, and similarly to the above, both valve bodies 20 and 21 are maintained in the closed position, the pressure inside the chamber 31 is held, and the temperature inside the vehicle is approximately the set temperature. will be maintained.

Thereafter, when the temperature inside the vehicle changes, the above-mentioned action is repeated to maintain the desired set temperature.

Note that the comparator circuit 12 sets a predetermined range for the set temperature so that none of the coils 16j7 is operated, that is, when the difference between the vehicle interior temperature and the set temperature rises or falls beyond the predetermined range, the comparator circuit 12 The pressure in the chamber 31 described above may be held effectively by setting the coil 17 or 16 to be excited.

However, since the door operates very slowly, and the electrical operation to operate the electromagnetic valve means 13 is performed quickly, the above-mentioned effect can be effectively achieved even if the above-described predetermined range is not substantially present.

By the way, when starting the vehicle when the temperature inside the vehicle is quite low, it is necessary to quickly rotate the door 37 counterclockwise in order to raise the temperature inside the vehicle as quickly as possible.

However, in the control device shown in FIG.
Because the orifice 39 disposed in the actuator 7 delays the transmission of negative pressure from the actuator 26 to the chamber 31, the vehicle interior temperature cannot be quickly approximated to the set temperature.

Therefore, an object of the present invention is to quickly transmit negative pressure to the actuator when starting the engine when the temperature inside the vehicle is low.

In order to achieve this object, the present invention disposes a first onofice in a first passage communicating between electromagnetic valves of an actuator for transmitting signal fluid pressure to the actuator, and bypasses the first passage. A check valve and a second orifice are arranged in series in the second passage, and the check valve has a configuration that allows fluid communication only in the direction from the actuator to the solenoid valve.

An embodiment embodying the present invention will be described below with reference to FIG.

In this embodiment □, parts having the same structure and function as those of the control device shown in FIG.

The solenoid valve means 50 shown in FIG. 2 is biased by a spring 51 to the position shown when no electrical signal is applied, thereby closing an inlet 52 leading to a negative pressure source and closing an inlet 53 leading to an atmospheric source. A single valve body 55 connected to the outlet 54 is used.

When the coil 57 is excited by the comparator circuit 56 which generates an electric signal when the vehicle interior temperature is lower than the set temperature, the valve body 55 is moved downward as shown in the figure against the spring 51 by the attraction force thereof. is closed and port 52 is opened to connect outlet 54 to a source of negative pressure.

The communication between the outlet 54 and the chamber 31 of the actuator 26 is
One passage 59 has an orifice 58 and the other passage 62 bypasses the passage 59 and has an orifice 60 and a check valve 61.

In this way, the transmission of negative or atmospheric pressure to the chamber 31 of the actuator 26 via the solenoid valve means 50 is controlled by the check valve 6.
1 is closed, a passageway 59 having an orifice 58
delayed and gradual.

Now, for example, when negative pressure is gradually introduced into the chamber 31 of the actuator 26 and the temperature inside the vehicle reaches the set temperature due to the slow operation of the door 37, the comparator circuit 12 causes the solenoid valve means 50 to become relatively It is quickly actuated to the illustrated position and the fluid pressure in the passage 59 is switched from negative pressure to atmospheric pressure, so that subsequent further increase in the negative pressure value in the chamber 31 of the actuator 26 is relatively quickly prevented. .

Therefore, actuator 2 that increases the temperature inside the vehicle
6 is prevented from further operation, the door 37 is held substantially in its position, and the temperature inside the vehicle is prevented from rising above the set temperature.

Thereafter, atmospheric pressure is slowly and gradually introduced into the chamber 31 by the orifice 58, so that the door 37 is gradually rotated clockwise.

When the temperature inside the vehicle becomes lower than the set temperature due to the slow operation of this door 37, the fluid pressure in the passage 59 is relatively quickly switched from atmospheric pressure to negative pressure by the comparator circuit 12 and the electromagnetic valve means 50. Therefore, further operation of the actuator 26 that would lower the temperature inside the vehicle is prevented, and the door 37 is held substantially in its position, so that the temperature inside the vehicle is lowered below the set temperature. This will be prevented.

Thereafter, by repeating the above action, the temperature in the vehicle interior does not rise or fall significantly from the set temperature, and the temperature in the vehicle interior does not change suddenly due to the slow operation of the door.

Here, the function of the other passage 62 will be explained.

It is desirable that the check valve 61 is set to open when the pressure on the downstream actuator 26 side is higher than the pressure on the upstream electromagnetic valve 50 side by a predetermined pressure.

Therefore, when the vehicle is started when the actuator chamber 31 is completely at atmospheric pressure, the negative pressure reaching the outlet 54 by the solenoid valve 50 opens the check valve 61 and also reaches the chamber 31 via the other passage 62.

At this time, the negative pressure reaching the chamber 31 is allowed to be transmitted relatively quickly through the roads 59 and 62, each having an orifice, and the door 37 is quickly and sufficiently rotated counterclockwise to open the heat exchanger 36. Allow sufficient ventilation through the

Therefore, when the temperature inside the vehicle is quite low, the temperature can be quickly approximated to the set temperature.

Note that the intake manifold negative pressure is at its maximum during idling, including when the vehicle is started, and normally some negative pressure remains in the chamber 31 when the actuator 26 is activated.

Therefore, by appropriately setting the predetermined pressure for opening the check valve 61, it is possible to set the check valve 61 to open only when the vehicle is started.

[Brief explanation of the drawing]

Figure 1 is a system diagram showing an example of a conventional control device, Figure 2 is a system diagram showing an example of a conventional control device.
The figure is a system diagram showing one embodiment of a control device according to the present invention. 10: Temperature setting circuit, 11: Vehicle interior temperature detection circuit, 1
2.56: Comparison circuit, 13,50: Solenoid valve means, 2
6: Actuator, 27, 59, 62: Passage, 36
: Heat exchanger for heating, 37: Door, 39.58, 60 Niorifice, 61: Check valve.

Claims (1)

[Scope of utility model registration request] a door for controlling the amount of air passing through the heating heat exchanger; an actuator actuated in response to a signal fluid pressure to control the operation of the door; a solenoid valve means for switching communication of the signal fluid pressure to the actuator; In a control device having a control circuit that compares a set temperature signal and a vehicle interior temperature signal and generates an electric signal for operating the solenoid valve means,
a first orifice disposed in a first passage communicating between the actuator and the solenoid valve means for transmitting the signal fluid pressure to the actuator; and a check in a second passage bypassing the first passage. A control device for an air conditioner, characterized in that a valve and a second orifice are arranged in series, and the check valve allows fluid communication only in the direction from the actuator to the solenoid valve means.