COOLING DEVICE AND COOLING METHOD FOR ENGINE

• US 20170074153A1
• Filed: 09/13/2016
• Published: 03/16/2017
• Est. Priority Date: 09/15/2015
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Onoda, Hidetoshi, KANEKO, Rihito, Takagi, Noboru, Takagi, Isao
• Granted Patent: US 10,227,910 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F01P 11/20 concerning atmospheric freezing conditions, e.g. automatically draining or heating during frosty weather
• CPC Class Codes: F01P 2007/146 using valves
• CPC Class Codes: F01P 2031/30 Cooling after the engine is stopped
• CPC Class Codes: F01P 2037/00 Controlling
• CPC Class Codes: F01P 2060/08 Cabin heater
• CPC Class Codes: F01P 3/20 Cooling circuits not specific to a single part of engine or machine F01P3/22 takes precedence
• CPC Class Codes: F01P 5/10 Pumping liquid coolant; Arrangements of coolant pumps
• CPC Class Codes: F01P 7/165 characterised by systems with two or more loops

Abstract

A cooling device for an engine includes a radiator route passing through a radiator, that are merged together after being branched on the downstream side from the inside of the engine in a coolant circuit configured to allow a coolant to flow from a pump through the inside of the engine and return to the pump. An at-stop control section provided in the cooling device controls a multiway valve that has three discharge ports, including a radiator port connected to the radiator route, so as to close the radiator port and open at least one of the other discharge ports when an ignition switch is turned off.

Claims

1. A cooling device for an engine, the cooling device comprising:

a coolant circuit including a pump, a radiator, and a plurality of routes,

the plurality of routes being configured such that a coolant flows from the pump through the inside of the engine and returns to the pump,

the plurality of routes being branched at a branching position on a downstream side from the inside of the engine,

the plurality of routes being each connected to the pump,

the plurality of routes including a radiator route, the radiator route passing through the radiator;

a multiway valve including a plurality of discharge ports,

the discharge ports being provided at the branching position of the plurality of routes in the coolant circuit,

the discharge ports being configured to discharge the coolant respectively to the plurality of routes,

the discharge ports including a radiator port, the radiator port being a discharge port that discharges the coolant to the radiator route,

the multiway valve being configured to switch open and closed states of the discharge ports, the open and closed states of the discharge ports including a state in which all the discharge ports are closed; and

an electronic control unit configured to control the multiway valve such that the radiator port closes and at least one of the discharge ports, other than the radiator port, opens when an ignition switch is turned off.

2. The cooling device according to claim 1, wherein

the plurality of routes include the radiator route, a heater route, and a third route, the heater route passing through a heater core,

the discharge ports include the radiator port, a heater port, and a third discharge port, the heater port is configured to discharge the coolant to the heater route, the third discharge port is configured to discharge the coolant to the third route,

the electronic control unit is configured to control the multiway valve such that the radiator port closes and the heater port opens when the ignition switch is turned off and an outside air temperature is equal to or lower than a predetermined temperature, and

the electronic control unit is configured to control the multiway valve such that the radiator port closes, the heater port closes and the third discharge port opens, when the ignition switch is turned off and the outside air temperature is higher than the predetermined temperature.

4. The cooling method according to claim 1, wherein

the plurality of routes include the radiator route, a heater route, and a third route, the heater route passing through a heater core,

the discharge ports include the radiator port, a heater port, and a third discharge port, the heater port is configured to discharge the coolant to the heater route, the third discharge port is configured to discharge the coolant to the third route,

the multiway valve is controlled such that the radiator port closes and the heater port opens when the ignition switch is turned off and an outside air temperature is equal to or lower than a predetermined temperature, and

the multiway valve is controlled such that the radiator port closes, the heater port closes and the third discharge port opens, when the ignition switch is turned off and the outside air temperature is higher than the predetermined temperature.

3. A cooling method for an engine, the engine including a cooling device, the cooling device including a coolant circuit and a multiway valve,

the coolant circuit including a pump, a radiator, and a plurality of routes,

the plurality of routes being configured to allow a coolant to flow from the pump through the inside of the engine and return to the pump,

the plurality of routes being branched at a branching position on a downstream side from the inside of the engine,

the plurality of routes being each connected to the pump,

the plurality of routes including a radiator route, the radiator route passing through the radiator;

and

the multiway valve including a plurality of discharge ports,

the discharge ports being provided at the branching position of the plurality of routes in the coolant circuit,

the discharge ports being configured to discharge the coolant respectively to the plurality of routes,

the discharge ports including a radiator port, the radiator port being a discharge port that discharges the coolant to the radiator route,

the multiway valve being configured to switch open and closed states of the discharge ports, the open and closed states of the discharge ports including a state in which all the discharge ports are closed,

the cooling method comprising;

controlling the multiway valve such that the radiator port closes when an ignition switch is turned off; and

controlling the multiway valve such that at least one of the discharge ports, other than the radiator port, opens when an ignition switch is turned off.