JPH08105568A - Electromagnetic type flow rate control valve - Google Patents

Abstract

PURPOSE: To reduce the flow rate variation in a small flow rate condition, and to extend the service life, in an electromagnetic type flow rate control valve which is duty controlled. CONSTITUTION: A spool valve 27 opened by rising a specific distance following the opening of a valve body 24 is provided, and plural stages of valve openings are to be given to the valve body 24 by feeding the power to plural solenoid coils 22A and 22B selectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic flow control valve suitable for controlling the flow rate of hot water in a hot water type air conditioner for a bath.

[0002]

2. Description of the Related Art A circuit diagram of a conventional air conditioner of this type is shown in FIG. 1 is a running engine of a bus, 2 is a pump built in the running engine 1, 3 is an oil combustion type preheater, 4 is a booster pump, 5 is a defrost heater, 6 is a fan for a defrost heater, and 7 is an electromagnetic flow control valve. ,
8 is an air conditioner heater, 9 is a fan for the air conditioner heater,
Reference numeral 10 is a sensor for detecting the temperature of the air taken in by the air conditioner heater 8, and 11 is a controller.

The hot water discharged from the pump 2 enters the preheater 3 as shown by the arrow, and after being heated there,
The booster pump 4 boosts the pressure. Most of the hot water discharged from the booth pump 4 enters the air conditioner heater 8 through the electromagnetic flow control valve 7, where the air in the vehicle compartment blown by the fan 9 is heated to lower the temperature and return to the pump 2. . The remaining portion enters the defrost heater 5, where the air blown by the fan 6 is heated to lower the temperature, and then joins the hot water flowing out from the air conditioner heater 8 and returns to the pump 2.

Based on the temperature detected by the sensor 10, the controller 11 controls the flow rate through the electromagnetic flow rate control valve 7, that is, the flow rate of hot water supplied to the air conditioner heater 8, so that the temperature inside the vehicle, that is, the air conditioner heater 8 is controlled. The intake air temperature is maintained at the target temperature.

A cross-sectional view of a conventional electromagnetic type flow control valve 7 is shown in FIG.
Is shown in. The electromagnetic flow control valve 7 includes a main body 21, an electromagnetic coil 22, a spring 23, a valve body 24, a header 25, a valve seat 26 and the like.

When the electromagnetic coil 22 is energized, the magnetic force attracts the valve body 24 and raises it against the spring 23, thereby separating from the valve seat 26 and opening the valve.

This electromagnetic flow control valve 7 has its electromagnetic coil.
When the voltage Vn as shown in FIG. 8 is applied to the valve 22, the valve is opened, and the ratio of the ON time T _M (valve opening time) and the OFF time T _B (valve closing time) is changed within a constant period T, that is, The time average flow rate is controlled by controlling the duty.

FIG. 9 shows the relationship between the valve opening time ratio T _M / T of the electromagnetic flow control valve 7 and the heat load factor of the air conditioner heater 8, and the valve opening time ratio T _M / T proportional to the heat load factor is shown. By giving T, the time average flow rate can be changed in proportion to the heat load rate.

FIG. 10 shows the relationship between the voltage supplied to the electromagnetic coil 22, the flow rate of hot water, and the temperature of the air blown from the air conditioner heater 8. The hot water is intermittently opened and closed by opening and closing the electromagnetic flow control valve 7. The temperature of the air flowing from the air conditioner heater 8 fluctuates periodically.

As shown in FIG. 11, the fluctuation range of the blown air temperature increases as the capacity of the electromagnetic flow control valve 7 increases and as the open / close cycle T of the electromagnetic flow control valve 7 increases.

[0011]

The smaller the fluctuation range of the temperature of the air blown out from the air conditioner heater 8, the better the air conditioning feeling. In order to reduce the fluctuation range, it is desirable to reduce the capacity of the electromagnetic flow control valve 7 or to shorten the opening / closing cycle T thereof, that is, to open / close at high speed.

However, the capacity of the electromagnetic type flow control valve 7 is
As shown in FIG. 9, the capacity sufficient to secure the flow rate required when the heat load rate is 100% is limited as the minimum value. Further, when the opening / closing cycle T is shortened, there has been a problem that the life of the electromagnetic flow control valve 7 is shortened due to rapid wear of the sliding portion inside the electromagnetic flow control valve 7.

[0013]

The present invention has been invented to solve the above problems, and the gist of the first invention is to open a valve by applying a voltage to an electromagnetic coil. In an electromagnetic flow control valve that is provided with a valve body and controls the flow rate by adjusting the energization time ratio to the electromagnetic coil within a fixed cycle, when a predetermined distance rises with the opening of the valve body. An electromagnetic flow control valve characterized by providing a spool valve to be opened and a plurality of electromagnetic coils, and selectively energizing the plurality of electromagnetic coils to give a plurality of stages of valve opening to the valve body. is there.

The gist of the second aspect of the invention is to provide a valve body that opens by applying a voltage to the electromagnetic coil, and control the flow rate by adjusting the energization time ratio to the electromagnetic coil within a fixed period. In the electromagnetic flow control valve for performing the above, a spool valve that opens when a predetermined distance rises accompanying the opening of the valve body, and a single electromagnetic coil are provided, and multiple voltage levels are applied to this electromagnetic coil. The electromagnetic flow control valve is characterized in that the valve body is provided with a plurality of valve opening degrees by being selectively applied.

[0015]

In the first aspect of the present invention, the flow rate can be duty-controlled by a plurality of valve capacities by selectively energizing a plurality of electromagnetic coils to give a valve body a plurality of valve opening degrees.

According to the second aspect of the present invention, the flow rate can be duty controlled by a plurality of valve capacities by applying a plurality of stages of voltage to a single electromagnetic coil to give a valve body a plurality of stages of valve opening. .

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT One embodiment of the present invention is shown in FIGS. As shown in FIG. 1, a plurality (two in the figure) of electromagnetic coils 22A and 22B are mounted on an upper portion of a main body 21 of the electromagnetic flow control valve 100. At the bottom of the body 21 is a spool valve
27, the outer peripheral surface of the cylindrical portion 27A of the spool valve 27 is fitted in a liquid-tight slidable manner with the inner surface of the cylindrical outflow passage 21A of the main body 21, and the upper end flange portion 27B contacts the shoulder upper surface 21B. Touching. The lower end of the valve body 24 is in contact with the upper end opening of the cylindrical portion 27A of the spool valve 27, that is, the valve seat portion 32.

The spool valve 27 is pushed upward by a spring 30 interposed between its lower end and a spring receiver 29. The spool valve 27 rises and its upper end stops 31.
When hitting, a plurality of ports 28 formed by penetrating through the upper part of the cylindrical portion 27A are exposed on the upper surface 21B of the shoulder portion. Other configurations are similar to those of the conventional one shown in FIGS. 6 and 7, and corresponding members are designated by the same reference numerals.

The operation of the electromagnetic type flow control valve 100 will be described with reference to FIGS. As shown in FIG. 2A, when a voltage is applied to the electromagnetic coil 22B at a duty ratio of T _M / T, the valve body 24 compresses the spring 23 and ascends. The amount of rise is adjusted so that the upper end of the spool valve 27 can contact the stopper 31. When the valve body 24 rises, the spool valve 27 is pushed by the spring 30 and rises in association with the valve body 24, so the valve seat 32 remains closed and the port 28 is exposed on the shoulder upper surface 21B. Open.

When the valve capacity when the port 28 is opened is A, T is the period, and T _M is the energization time to the electromagnetic coil 22B, in the state of (a), it is represented by (T _M / T) A. Time average flow rate flows.

As shown in FIG. 2B, the electromagnetic coil 22B
When the voltage is constantly applied to the spool valve 27, the duty ratio is
It becomes 100% and the valve capacity becomes A.

As shown in FIG. 2C, the electromagnetic coil 22B
When a voltage is applied to the electromagnetic coil 22A with a duty ratio of T _M / T while always being energized to, the valve body 24 rises until it contacts the head 25, and the spool valve 27 also contacts the stopper 31 accordingly. Rise to. This allows port 28
And the valve seat 32 is also opened, and the valve capacity in this state is A when the valve capacity when the valve seat 32 is open is B.
It becomes + (T _M / T) B.

As shown in FIG. 2D, the electromagnetic coil 22A
, 22B is always energized, the valve capacity is A + B
Becomes

FIG. 3 shows the relationship between the valve capacity of the electromagnetic flow control valve 100, the valve opening time ratio T _M / T of the port 28 and the valve seat 32, and the heat load factor of the air conditioner heater 8. In this example, for simplicity, the capacity A when the valve seat 32 is open and the port 28
The valve capacities B when opened are the same. As the heat load rate increases, the energization duty ratio T _M / T to the electromagnetic coil 22B is increased to 0 to 100% while the electromagnetic coil 22A is not energized, and then the electromagnetic coil 22B is continuously energized to the electromagnetic coil 22A. Energization duty ratio T _M / T of 0 to 100%
Have been increased to. By doing so, the total valve capacity of the electromagnetic flow control valve 100 changes linearly with the heat load factor, and the cyclic change amount of the capacity is reduced to 1/2 of that of the conventional valve shown in FIG. To do.

A second embodiment of the present invention is shown in FIGS. Electromagnetic flow control valve according to the second embodiment
The structure of 200 is the same as that of the first embodiment shown in FIG. 1 except that it has a single electromagnetic coil 33 and the voltage applied to it is in two stages.

As shown in FIG. 5 (a), a voltage that allows only the spool valve 27 to open is applied to the electromagnetic coil 33 by a duty ratio T _M /
When applied at T, the valve capacity becomes ( _TM / T) A, and when the same voltage is constantly applied as shown in FIG. 5B, the valve capacity becomes A.

When the voltage shown in FIG. 5D is applied to the electromagnetic coil 33, the valve capacity becomes A + (T _M / T) B.
When the voltage shown in (c) is applied, the valve capacity becomes A + B.

As a result, the total valve capacity characteristic of this electromagnetic type flow control valve 200 becomes similar to that shown in FIG. 3, and the amount of periodic change in valve capacity is reduced to half that of the conventional one.

[0029]

According to the present invention, since the flow rate can be duty controlled by a plurality of valve capacities by giving a valve body a plurality of stages of valve opening, a periodic change of the valve capacity can be achieved without reducing the total valve capacity. The amount can be reduced as compared with the conventional one and its life can be extended.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an electromagnetic flow control valve according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between an energization pattern and a capacity of the electromagnetic flow control valve according to the first embodiment.

FIG. 3 is a diagram showing a capacity characteristic of the electromagnetic type flow control valve according to the first embodiment.

FIG. 4 is a vertical sectional view of an electromagnetic flow control valve according to a second embodiment of the present invention.

FIG. 5 is a diagram showing a relationship between an energization pattern and a capacity of an electromagnetic flow control valve according to a second embodiment.

FIG. 6 is a circuit diagram of a conventional hot water type air conditioner for a bus.

FIG. 7 is a vertical sectional view of a conventional electromagnetic flow control valve.

FIG. 8 is a diagram showing an energization pattern of a conventional electromagnetic flow control valve.

FIG. 9 is a diagram showing a capacity characteristic of a conventional electromagnetic flow control valve.

FIG. 10 is a diagram showing a relationship between a supply voltage to an electromagnetic coil, a hot water flow rate, and an air conditioner heater blowout temperature in a conventional air conditioner.

[FIG. 11] Capacity of a solenoid valve in a conventional air conditioner,
It is a diagram which shows the relationship between a period and the air-conditioner heater blowing temperature fluctuation range.

[Explanation of symbols]

 100 solenoid valves 22A, 22B, solenoid coil 24 valve disc 27 spool valve

Claims (2)

[Claims] 1. An electromagnetic flow control valve comprising a valve body which opens by applying a voltage to an electromagnetic coil, and which controls the flow rate by adjusting the energization time ratio to the electromagnetic coil within a fixed cycle. A spool valve that opens when a predetermined distance rises accompanying the opening of the valve body,
An electromagnetic flow control valve, wherein a plurality of electromagnetic coils are provided, and a plurality of stages of valve opening are given to the valve body by selectively energizing the plurality of electromagnetic coils. 2. An electromagnetic flow control valve comprising a valve body which is opened by applying a voltage to an electromagnetic coil, and which controls the flow rate by adjusting the energization time ratio to the electromagnetic coil within a fixed cycle. A spool valve that opens when a predetermined distance rises accompanying the opening of the valve body,
An electromagnetic flow control valve, wherein a single electromagnetic coil is provided, and a plurality of stages of voltage are selectively applied to the electromagnetic coil to give the valve body a plurality of stages of valve opening.