JP2009209708A - Cooling water circuit for automobile, and method for controlling cooling water circuit for automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling water circuit for an automobile, and a method for controlling a cooling water circuit for an automobile, in which flow of water to a heater core is secured to secure heating performance in a situation where quick heating performance is demanded in cold start or the like, and quick heating performance of a water-cooled engine is secured, while restricting cost increase. <P>SOLUTION: In a cooling water circulation circuit 11, cooling water is circulated between the water-cooled engine 1 and a radiator 2, and the heater core 3 is provided on a bypass circuit 31 provided in parallel with the radiator 2. An electric pump 4 that is flow-regulatable, and changeable between normal and reverse flow directions, is provided on the cooling water circulation circuit 11. A check valve 5 is provided on a circuit 21 on the side of the radiator 2 provided in parallel with the heater core 3 for prohibiting reversing of the flow direction of cooling water. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to an automotive coolant circuit and a control method for an automotive coolant circuit.

Conventionally, an engine-driven mechanical pump has been adopted for cooling water circulation in most types of vehicles employing a water-cooled engine. The flow rate of this mechanical pump is determined by the engine speed, and in principle, the flow rate cannot be controlled by the mechanical pump body. For this reason, a thermostat is provided in the radiator circuit in order to improve quick warming and adjust the water temperature, and a heater core is provided in a bypass circuit provided in parallel with the radiator circuit (see, for example, Patent Document 1).
JP 2007-182859 A

However, since the engine-driven mechanical pump cannot perform arbitrary flow rate control as described above, more than necessary cooling water may flow even in situations where quick warming is required, such as during cold start. Therefore, although a bypass circuit combined with a normal thermostat is provided, water that does not contribute to cooling flows after the warm-up ends, leading to a loss of operation of the pump.
Moreover, since a thermostat is located in a flow path, water flow resistance will increase.

Therefore, there is a system that improves the quick warm-up at the cold start by adopting an electric water pump that can change the flow rate arbitrarily, but when the thermostat is abolished to reduce water flow resistance Since the radiator is connected in parallel with the heater core, when the flow rate to the radiator is reduced, the water flow rate to the heater core is also reduced, and the heating performance is lowered.
Therefore, it is necessary to provide an electronic control valve mechanism in order to ensure the flow distribution to the heater core, leading to a problem of increasing costs.

  The problem to be solved by the present invention is to prevent the cost increase and secure the water flow to the heater core in a situation where quick warming is required, such as during cold start, to ensure the heating performance, An object of the present invention is to provide an automotive coolant circuit and a method for controlling the automotive coolant circuit that can ensure quick warming.

  In order to solve the above-described problem, the automotive coolant circuit according to claim 1 circulates coolant between a water-cooled engine and a radiator, and a coolant circuit in which a heater core is provided in a bypass circuit provided in parallel with the radiator. In the circuit, a circulation pump means capable of adjusting the flow rate and switching the flow direction between the normal flow and the reverse flow is provided in the cooling water circulation circuit, and a reverse flow in the flow direction of the cooling water is provided in a circuit on the radiator side provided in parallel with the heater core. A check valve for preventing the above is provided.

  According to a fourth aspect of the present invention, there is provided a control method for an automotive coolant circuit, wherein coolant water is circulated between a water-cooled engine and a radiator, a heater core is provided in a bypass circuit provided in parallel with the radiator, A circulation pump means that can adjust the flow rate and switch the flow direction between normal flow and reverse flow is provided, and a check valve that prevents reverse flow in the flow direction of the cooling water is provided in the circuit on the radiator side that is provided in parallel with the heater core. In the automotive cooling water circuit, when the water-cooled engine is required to be fast and warm, such as during cold start, the flow direction of the circulation pump means is switched to the reverse flow, and the cooling water is circulated in a direction that reduces the circulating flow rate. The means for controlling the pump means was used.

  In the automotive coolant circuit according to the first aspect of the present invention, as described above, the coolant circulation circuit is provided with circulation pump means capable of adjusting the flow rate and switching the flow direction between the normal flow and the reverse flow, and in parallel with the heater core. In the situation where quick warming of the water-cooled engine is required at the time of cold start or the like by adopting a configuration in which a check valve for preventing a reverse flow in the flow direction of the cooling water is provided in the circuit on the radiator side provided By switching the flow direction of the circulation pump means to the reverse flow, the flow of the cooling water to the circuit on the radiator side is stopped by the check valve to ensure quick warming of the water-cooled engine and the cooling water to the heater core Since the flow is secured, the heating performance can be secured.

  In addition, since the flow rate of the cooling water can be adjusted in the circulation pump means, the cooling water can be circulated to the heater core by a necessary flow rate.

  Note that the check valve has a simple structure compared to the case where an electronic control valve mechanism is provided and does not require a control mechanism, so that the cost increase can be suppressed, and the flow resistance of cooling water can be reduced compared to the case where a thermostat is provided. Can be reduced.

  5. The method for controlling an automotive cooling water circuit according to claim 4, wherein the flow direction of the circulation pump means is switched to the reverse flow in a situation where quick warming of the water-cooled engine is required, such as during cold start, By controlling the circulation pump means in the direction of decreasing the flow, the flow of cooling water to the circuit on the radiator side is stopped by the check valve to ensure the quick warming of the water-cooled engine and to the heater core Since the water flow is ensured, the heating performance can be ensured.

  In addition, by suppressing the flow rate to the heater core to the necessary minimum during that period, the quick heating effect of the water-cooled engine can be enhanced.

  Embodiments of the present invention will be described below with reference to the drawings.

  The automotive coolant circuit according to the first embodiment corresponds to the invention described in claims 1, 2, and 4.

  First, the automotive coolant circuit of the first embodiment will be described with reference to the drawings.

  FIG. 1 is a circuit diagram showing a normal running time in the automotive coolant circuit of the first embodiment, and FIG. 2 is a circuit diagram showing a cold start in the automotive coolant circuit of the first embodiment.

  As shown in FIG. 1, this automotive coolant circuit circulates coolant between a water-cooled engine 1 and a radiator 2, and a heater core 3 is provided in a bypass circuit 31 provided in parallel with the radiator 2. In the cooling water circulation circuit 11, a single electric pump (circulation pump means) 4 that can adjust the flow rate and switch the flow direction between the normal flow and the reverse flow is provided in the cooling water circulation circuit 11.

  The radiator 2 is an engine cooling heat exchanger that cools the cooling water heated by the water-cooled engine 1 by exchanging heat with outside air such as traveling wind.

  The heater core 3 is a heat exchanger for an air conditioner that heats the cooling water heated by the water-cooled engine 1 with the outside air introduced into the vehicle interior to warm the vehicle interior.

  The circuit 21 on the side of the radiator 2 provided in parallel with the heater core 3 is provided with a check valve 5 that prevents a reverse flow in the flow direction of the cooling water.

  Next, operations and effects of the first embodiment will be described.

  Since the automotive coolant circuit according to the first embodiment is configured as described above, in a situation where quick warming of the water-cooled engine 1 is required at the time of cold start or the like, as shown in FIG. The flow direction is switched from normal flow (see FIG. 1) to reverse flow.

  Then, since the check valve 5 is provided in the circuit 21 provided with the radiator 2, the cooling water flows to the water-cooled engine 1 through the bypass circuit 31 provided with the heater core 3.

  As a result, the cooling water circulates around the radiator 2 having a large heat exchange capacity, thereby ensuring the quick warming of the water-cooled engine 1.

  Moreover, since the flow of the cooling water to the heater core 3 is ensured during that period, the heating performance can be ensured.

  Furthermore, in this state, the electric pump 4 can be controlled to reduce the flow rate of the cooling water, and the cooling water can be circulated to the heater core 3 by the required flow rate. Thereby, the quick heating effect of the water-cooled engine 1 can be enhanced.

  Next, when the water-cooled engine 1 is warmed to a predetermined temperature or more, as shown in FIG. 1, the flow direction of the electric pump 5 is switched to a positive flow.

  Then, the cooling water from the water-cooled engine 1 passes through the check valve 6 and flows to the radiator 2, while flowing through the heater core 3 and returning to the water-cooled engine 1. Thereby, while being able to cool the water cooling engine 1 efficiently, sufficient heating effect can be acquired with the temperature of the cooling water heat-exchanged with the water cooling engine 1.

  Further, the check valve 5 has a simple structure compared to the case where an electronic control valve mechanism is provided and does not require a control mechanism, so that it is possible to suppress an increase in cost, and the circulation of cooling water compared to the case where a thermostat is provided. Resistance can be reduced.

  Next, another embodiment will be described. In the description of the other embodiments, the same components as those of the first embodiment are not shown, or the same reference numerals are given and the description thereof is omitted, and only the differences are described.

  The automotive coolant circuit according to the second embodiment corresponds to the first and third aspects of the invention.

  The second embodiment shows a modification of the automotive coolant circuit in the first embodiment. As shown in the circuit diagram of FIG. 3, the circulating pump means is provided in parallel with the coolant circulating circuit 11. It is comprised by the two electric pumps 41 and 42 which can adjust flow volume provided in the flow paths 12 and 13, respectively, and it arrange | positions so that the flow direction of both these electric pumps 41 and 42 may become a normal flow and a reverse flow.

  That is, in the second embodiment, in a situation where quick warming of the water-cooled engine 1 is required, such as during cold start, the cooling water circulation circuit is driven by driving the electric pump 42 as indicated by the dotted arrow in FIG. The flow direction of the cooling water in 11 is a reverse flow.

  Then, since the check valve 5 is provided in the circuit 21 provided with the radiator 2, the cooling water flows to the water-cooled engine 1 through the bypass circuit 31 provided with the heater core 3.

  As a result, the cooling water circulates around the radiator 2 having a large heat exchange capacity, thereby ensuring the quick warming of the water-cooled engine 1.

  Moreover, since the flow of the cooling water to the heater core 3 is ensured during that period, the heating performance can be ensured.

  Furthermore, in this state, the electric pump 42 can be controlled to reduce the flow rate of the cooling water, and the cooling water can be circulated to the heater core 3 by the required flow rate. Thereby, the quick heating effect of the water-cooled engine 1 can be enhanced.

  Next, when the water-cooled engine 1 is warmed to a predetermined temperature or higher, the driving of the electric pump 42 is stopped and the electric pump 41 is driven, so that the cooling water circulation circuit 11 in the cooling water circulation circuit 11 is driven as shown by the solid line arrow in FIG. Switch the flow direction of cooling water to positive flow.

  Then, the cooling water from the water-cooled engine 1 passes through the check valve 5 and flows to the radiator 2, while flowing through the heater core 3 and returning to the water-cooled engine 1. Thereby, while being able to cool the water cooling engine 1 efficiently, sufficient heating effect can be acquired with the temperature of the cooling water heat-exchanged with the water cooling engine 1.

As described above, in the second embodiment, the same effects as in the first embodiment can be obtained.
Further, in the second embodiment, since the two electric pumps 41 and 42 are provided, a function of switching between the normal flow and the reverse flow is not necessary. Therefore, a centrifugal pump having a higher efficiency than an axial flow pump or the like having a switching function. The additional effect that it becomes possible to use is obtained.

  Although the present embodiment has been described above, the present invention is not limited to the above-described embodiment, and design changes and the like within a scope not departing from the gist of the present invention are included in the present invention.

  For example, in the second embodiment, the flow rates of both the electric pumps 41 and 42 can be adjusted. However, the flow rate of the positive-side electric pump 41 may not necessarily be adjustable.

It is a circuit diagram which shows the time of normal driving | running | working in the cooling water circuit for motor vehicles of Example 1. FIG. It is a circuit diagram which shows the time of the cold start in the cooling water circuit for motor vehicles of Example 1. FIG. It is a figure which shows the cooling water circuit for motor vehicles of Example 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Water cooling engine 11 Cooling water circulation circuit 12 Flow path 13 Flow path 2 Radiator 21 Radiator side circuit 3 Heater core 31 Bypass circuit 4 Electric pump (circulation pump means)
41 Electric pump (circulation pump means)
42 Electric pump (circulation pump means)
5 Check valve

Claims (4)

In the cooling water circulation circuit in which the cooling water is circulated between the water cooling engine and the radiator, and the heater core is provided in the bypass circuit provided in parallel with the radiator,
The cooling water circulation circuit is provided with a circulation pump means capable of adjusting the flow rate and capable of switching the flow direction between forward flow and reverse flow,
A cooling water circuit for an automobile, wherein a check valve for preventing a reverse flow in the flow direction of the cooling water is provided in a circuit on a radiator side provided in parallel with the heater core.   2. The automobile cooling water circuit according to claim 1, wherein the circulation pump means comprises a single electric pump capable of adjusting a flow rate and switching a flow direction in the cooling water circulation circuit. Cooling water circuit. The automotive coolant circuit according to claim 1, wherein the circulation pump means is composed of two electric pumps with adjustable flow rates respectively provided in both flow paths provided in parallel to the coolant circulation circuit,
An automotive coolant circuit, wherein the electric pumps are arranged so that the flow directions of the electric pumps are normal and reverse. Cooling water is circulated between the water-cooled engine and the radiator, and a heater core is provided in a bypass circuit provided in parallel with the radiator. The flow rate can be adjusted in the cooling water circulation circuit, and the flow direction can be switched between the forward flow and the reverse flow. In an automotive coolant circuit in which a non-circulation pump means is provided, and a check valve for preventing a reverse flow in the flow direction of the coolant is provided in a circuit on the radiator side provided in parallel with the heater core,
In a situation where quick warming of the water-cooled engine is required such as during cold start, the flow direction of the circulation pump means is switched to a reverse flow, and the circulation pump means is controlled in a direction to reduce the circulation flow rate of the cooling water during that time. A method for controlling a cooling water circuit for an automobile, which is characterized in that

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