Abstract: A cooling system for an internal combustion engine includes a radiator provided in a coolant circulation path of the internal combustion engine, and an actuator that controls a flow rate of a coolant that passes through the radiator. In the cooling system, the actuator is controlled so that a coolant temperature of the engine becomes substantially equal to a target coolant temperature. The cooling system calculates a cooling loss as a quantity of heat removed from the engine by the coolant, based on an operating state of the engine, and calculates a required radiator flow rate, based on the cooling loss, the target coolant temperature, and a temperature of the coolant that has passed through the radiator. The required radiator flow rate represents a quantity of the coolant required to pass through the radiator so as to achieve the target coolant temperature. The cooling system then controls the actuator based on the required radiator flow rate.

Abstract: The present invention relates to a method of controlling an electronic thermostat valve that is based on the driving conditions. The method includes using controlling parameters memorized in an ECU (Electronic Control Unit). A power source to activate the thermostat valve is originated from an expanding force of a thermal element and a change of stroke of an actuating means. A cooling system of a vehicle can be maintained in an optimized state such that fuel consumption and exhaust pollutants are reduced.

Abstract: A thermostatic valve for a coolant circuit of an internal combustion engine, with a housing through which the flow is capable of passing and which has a first throughflow orifice for connection to a first coolant line, a second throughflow orifice for connection to a second coolant line, and a third throughflow orifice for connection to a third coolant line, and with a closure member which is mounted in the housing and which can be adjusted by an actuating unit, the closure member having a first shut-off element for shutting off the first throughflow orifice and a second shut-off element, coupled to the first shut-off element, for shutting off the second throughflow orifice.

Abstract: An engine cooling water passage structure includes a cooling water passage unit that is formed by integrating a water pump for supplying cooling water, a thermostat housing for housing a thermostat, a gas/liquid separation chamber for separating air from the cooling water, cooling water supply passages for supplying to water jackets, via the thermostat housing and the water pump, the cooling water that has been returned from a radiator, cooling water discharge passage for discharging into the radiator the cooling water that has passed through the water jackets, and a bypass passage for returning to the thermostat housing the cooling water that has passed through the water jackets, while bypassing the radiator. This cooling water passage unit is detachably mounted as a unit on an engine main body. Thus, the arrangement allows the engine cooling system to be made compact.

Abstract: A flow control valve used in a cooling system of a water cooling type includes a first valve body and a first valve seat for controlling a quantity of radiator flow which returns from an engine to a pump through a radiator, a second valve body and a second valve seat for controlling a quantity of bypass flow which returns from the engine to the pump without passing through the radiator, and a step motor for displacing the valve bodies integrally as a valve unit. The first valve body, the first valve seat, the second valve body, and the second valve seat are so arranged that, in a range where the radiator flow quantity becomes practically zero, the bypass flow is permitted to flow at a slightly larger quantity than the radiator flow and, in other ranges, the bypass flow quantity is equal to or lower than the radiator flow quantity.

Abstract: An engine cooling system includes a flow control valve and an electronic control unit (ECU) for controlling the flow control valve. The flow control valve regulates the flow rate of coolant flowing through a radiator in a coolant circuit. The ECU feedback controls the opening size of the flow control valve such that the temperature of coolant at an engine outlet seeks a predetermined target value. During the feedback control, the ECU controls the flow control valve such that the opening size of the flow control valve remains above a predetermined lowest value. As a result, the flow control valve is prevented from falling in a small opening size range in which in which it is difficult to cause the engine outlet coolant temperature to seek the target value, and the engine outlet coolant temperature is favorably adjusted.

Abstract: A cooling system for an engine wherein a cylinder block side is mounted with a stagnation chamber for stagnating a temperature sensing unit of a sub-thermostat portion of cooling water discharged to a high temperature passage via an outlet of a cooling water passage of the cylinder block side, enabling opening and closing of the sub-thermostat only via the temperature of the cooling water at the cylinder block side. The cooling system includes a main thermostat and a sub-thermostat for individually controlling the flow of cooling water in a cylinder block and a cylinder head. The stagnation chamber, where a cooling water discharged from the cylinder block is stagnated, is installed inside a sub-thermostat housing where a sub-thermostat is mounted. The stagnation chamber is positioned therein with a temperature sensing unit. The stagnation chamber communicates with a cooling water discharge passage of the cylinder head via a confluence passage.

Abstract: The present invention removes the problem conventionally confronted by electronically controlled thermostats that implementation of improved fuel consumption is difficult, and implements high cooling-water temperature controllability, improved fuel consumption, and an improvement of the heater function and so forth with high accuracy and at low cost.

Abstract: A valve for regulating fluid flow and associated method of use. The valve includes a stepper motor, a first valve chamber having an inlet port, a second valve chamber having an outlet port, wherein the first valve chamber includes an opening between the first valve chamber and the second valve chamber, a first member that is rotatable and operatively attached to the stepper motor, a second member that engages the first member for linear movement of the second member between a first position and a second position when the first member is rotated by the stepper motor, and a sealing mechanism that is operatively attached to the second member, wherein the sealing mechanism can move adjacent to the opening when the second member is in the first position and the sealing mechanism can move away from the opening when the second member is in the second position.

Abstract: In the field of cooling of internal combustion engines a known characteristic of thermostatic flow control valves is their lagging control response to variable rates of internal heat generation in the engine. Further, there is a thermal inertia effect due to engine mass and internal fluids masses which masks imbalances between instantaneous internal heating and cooling rates, in many cases allowing internal temperatures to rise excessively and pre-ignition damage or other heat-related component damage to occur to the engine system. The invention seeks to overcome these known characteristics using simple apparatus with a method to effect improved operation of the cooling system.

Abstract: A U flow radiator 10 with a header tank 12 split into inlet and outlet sides I and O by a lengthwise divider wall 18 has a coolant inlet consisting of a cylindrical pipe 22. A hollow cylindrical barrel 24 co extensive and coaxial with pipe 22 and extending across divider wall 18, with cut outs 26 and 28 opening respectively into both sides I and O. A thin walled, hollow cylindrical sleeve 30 turns within barrel 24 with windows 36 and 38 that alternately block or open the cut outs 26 and 28, or open both partially. A rotary actuator 40 turns sleeve 30 within barrel 24. Coolant can be selectively routed all to the tank outlet side O, by passing the radiator 10 for quick warm up. After warm up, coolant can be routed to I or O in desired proportions to increase or decrease cooling capacity. With high engine cooling demand, all coolant is routed to the inlet side I and all coolant passes through radiator 10.

Abstract: The invention provides an engine cooling device capable of suitably promoting the warm-up of an engine. This engine cooling device comprises a cooling circuit and a heat-accumulating passage. The cooling circuit is composed of a radiator passage, a bypass passage, and a flow rate control value for controlling the flow rate of coolant flowing though the bypass passage. The heat-accumulating passage is provided with a heat-accumulating container, and constitutes a heat-accumulating circuit for causing coolant in the heat-accumulating container to circulate via the engine. The cooling device completes the heat-accumulating circuit by connecting the heat-accumulating passage to the cooling circuit to supply the cooling medium in the heat-accumulating container to the body of the engine, opens the flow rate control valve to increase a flow rate of cooling medium flowing though the bypass passage, then disconnects the heat-accumulating passage from the cooling circuit, and closes the flow rate control valve.

Abstract: A coolant circuit (10) includes at least one heat source (12), a radiator (14), and a bypass line (22), which connects a radiator inlet (18) to a radiator return (20) and whose junction (24) has a control valve (26) disposed on it, whose throttle body (58) can be electrically triggered as a function of operating parameters and environmental parameters by means of at least one control unit (40, 42) and divides the coolant flow between the radiator inlet (18) and the bypass line (22). According to a characteristic curve of the control valve (26), the control unit (40, 42) determines a set-point value (50) for the position of the throttle body (58), which sets a ratio of the radiator volume flow to the total coolant flow at the control valve (26).

Abstract: The invention relates to a coolant circuit for a motor vehicle having an engine and a radiator. The coolant circuit includes an exhaust gas heat exchanger and enables engine coolant coming from the radiator to be supplied directly to the exhaust gas heat exchanger. In a preferred embodiment, coolant coming from the radiator and/or from the engine can be selectively supplied to the exhaust gas heat exchanger via a changeover device.

Abstract: The control valve (10) comprises a body (12) having a fluid inlet (28), a first outlet (18) connected to a first branch of the circuit, a second outlet (20) connected to a second branch of the circuit and a third outlet (22) connected to a third branch of the circuit, as well as an adjustment member (34) suitable for taking in succession at least the following positions: a “bypass” position (P1), at which the first outlet (18) is open; a “radiator+bypass” position (P2; P3), at which the first outlet (18) and the second outlet (20) are open; a “radiator” position (P9), at which the second outlet (20) is open; a “radiator+unit heater” position (P4; P10), at which the second outlet (20) and the third outlet (22) are open; a “radiator+bypass+unit heater” position (P6; P7), at which the first outlet (18), the second outlet (20) and the third outlet (22) are open; a “unit heater+bypass” position (P5), at which the first

Abstract: An electronically controlled thermostat is obtained enabling stable valve body actuation, preventing overshooting and hunting, and with a reduced overall device size and simplified construction. An electronically controlled thermostat 1 capable of arbitrary variable control of cooling water temperature comprises a thermo-element 4 having a piston which actuates the opening and closing within a housing of a first valve body 11 and a second valve body 18 to perform switching of the flow path of cooling water by sensing the cooling water temperature, and an element guide member 25 which holds the thermo-element within the above housing 10. A temperature-sensing chamber is provided, formed by isolation by the element guide member from the flow path in which cooling water on the radiator exit side flows; the temperature-sensing portion of the element 4 is disposed so as to face this [chamber]vii.

Abstract: A method for adjusting coolant temperature in an internal combustion engine (2), whereby the coolant circuit thereof contains an electrically driven coolant pump (3) and an electrically controllable bypass valve (4). If the setpoint value of the coolant temperature changes in an abrupt manner, the rotating speed of the coolant pump (3) rises during a short interval in order to reduce the dead time required for adjustment.

Abstract: The improved internal combustion engine of the cam drive axial piston type includes modification to the drive shaft, bearings and other internal elements to facilitate the flow of oil and lubricants to engine parts. The cooling system is modified to allow coolant flow directly to the engine block and head assembly simultaneously and to control flow through the engine and radiator to reduce hot spots. The valves and valve crown structure have been modified for ease of assembly and reliability of the roller valve lifter and valve interface. Use of alternate fuel supply systems which eliminate the need for a valve train are also accommodated. The drive shaft and engine have been modified to allow the mounting of a variety of aircraft propellers using a hub as well as mounting a flywheel for reduced start motor stress.

Abstract: A thermostat apparatus is provided. The thermostat apparatus comprises a thermostat and a positioner for establishing different operating temperatures for thermostat.

Abstract: A water-cooled multi-cylinder internal-combustion engine having a crankcase and cooling ducts which surround the cylinders and which are acted upon by coolant by way of a pump in a small cooling circuit. For switching over to a large cooling circuit provided with a radiator, a thermostat is provided which is inserted in a thermostat housing. The thermostat housing has a top part provided with coolant connections and a bottom part preferably integrated in the crankcase. An insertion part is inserted in the bottom part of the thermostat housing, which insertion part has at least one opening which is controlled by the thermostatic valve for controlling the flow in the small and the large cooling circuit.

Abstract: A dual temperature control system as part of an engine cooling system. In one aspect, a valve is regulated as a function of engine load and disposed in a by-pass line between the radiator and the coolant pump. The valve is designed to normally block the by-pass line, but permits coolant to by-pass the thermostat and be conveyed from the radiator to the engine when the load of the engine approaches a wide-open-throttle condition. In another aspect, both high-temperature and low-temperature thermostats are employed and a normally closed valve is actuated when the load of the engine approaches a wide-open-throttle condition to permit coolant to be conveyed through the low-temperature thermostat and on to the engine.

Abstract: An engine thermal management system and method for a vehicle engine that allows for reduced coolant flow and energy consumption by the system, while avoiding excessive critical metal temperatures in the engine. The engine includes a coolant inlet in a head and a coolant outlet in a block. A variable speed pump pushes the coolant into the head inlet. A multi-port valve receives the coolant exiting the engine block and selectively routes it to various system components. The speed of the pump and the valve are electronically controlled by a control module, based upon various engine and vehicle operating conditions.

Abstract: In an internal combustion engine with cylinders and a crankshaft, coolant discharged from a coolant circulating pump is supplied to a coolant jacket formed in a cylinder block via a coolant jacket formed in a cylinder head. An inlet port through which the coolant discharged from the coolant circulating pump flows into the coolant jacket is provided at one end portion of the cylinder head on an intake side thereof in a cylinder-head center line direction, whereas an outlet port through which the coolant in the coolant jacket is allowed to flow out into a heater core is provided at the other end portion of the cylinder head on an exhaust side thereof.

Abstract: A valve for automatically and proportionally adjusting fluid flow between an engine and a radiator for cooling the fluid heated by the engine in response to changes in fluid temperature within a range of operating temperatures. The valve includes a housing having a chamber. The housing includes a radiator flow port for passing fluid between the radiator and the chamber, a bypass flow port for passing fluid between the engine and the chamber, and an engine flow port for passing fluid between the chamber and the engine. A vane disposed in the chamber has a vane wall engagable with both the radiator and bypass fluid ports for restricting fluid flow through the radiator and bypass fluid ports. The vane is pivotally coupled to the housing for movement between the radiator and bypass fluid ports. A drive assembly is operatively coupled to the vane for varying the position of the vane within the chamber.

Abstract: In a cooling system of an internal combustion engine, coolant flowing through a radiator and bypassing the radiator are mixed in a flow control valve controlled by ECU on the basis of signals provided by sensors such as a coolant temperature sensor, so that the coolant is circulated by an electric pump to control the coolant temperature for the internal combustion engine. A desired coolant temperature is changed according to the operating condition of the internal combustion engine, the traveling condition of a vehicle and the ambient condition. Thus, the temperature of the coolant flowing into the internal combustion engine is changed properly so that frictional resistance in the engine and exhaust gas may be reduced and the internal combustion engine may be kept at its most efficient temperature near a detonation limit temperature.

Abstract: A control valve (10) for a control circuit (30) having at least one first control unit (14) that, depending on at least one operating parameter and/or the ambient temperature, releases, throttles, or closes a branch of flow (32) to a heat exchanger (16), and controls a bypass line (34) in complementary fashion. The control unit (14) generates a setpoint (36) for the position of a valve member (26) driven via electric motor or electromagnetically, which is processed by a second electronic control unit (20) integrated in the control valve (10) with a determined actual value (38) of the position of the valve member (26) to a position variable for the position of the valve member (26).

Abstract: A controller provided in accordance with the invention determines a failure of a thermostat that opens and closes a passage through which cooling water circulates between a radiator and an engine. The controller prohibits the failure determination if a water temperature of the engine decreases by more than a predetermined amount during a predetermined period from the time when a rotational speed of the engine exceeds a predetermined rotational speed. Thus, when the thermostat opens due to a high rotational speed of the engine, the failure determination is prohibited. Therefore, it is avoided that the thermostat operating normally is judged to be faulty.

Abstract: A coolant flow valve for controlling the distribution and flow of coolant to replace the radiator thermostat and heater valve currently used in automotive applications. The valve includes a valve rotor rotationally received in a valve housing wherein the rotational orientation thereof determines which combination of flow paths through four different outlet ports is selected.

Abstract: An engine cooling system controls a cooling degree of an engine 1 according to an operating condition thereof by circulating cooling water through the engine. This system is provided with a water temperature sensor 31 for detecting a cooling water temperature THW1, a flow rate regulating valve 8 for regulating a circulation flow rate of the cooling water, and an electronic control unit (ECU) 30 for controlling the valve 8. The ECU 30 sets a non-control region and a first and second control regions, each centering on a target water temperature to be calculated according to operating conditions of the engine 1.

Abstract: An engine cooling apparatus includes a flow regulating valve, which adjusts a flow rate of a coolant passing through a radiator provided in a coolant circulation passage of the engine, and an electronic control unit (ECU), which controls an opening of the flow regulating valve such that an engine outlet coolant temperature reaches a necessary target temperature. The ECU sets a basic opening as a feedforward term based on the operation state of the engine. The ECU calculates a final opening from an F/B constant as a feedback term, which is increased or decreased such that the engine outlet coolant temperature reaches the target temperature, and the basic opening. Further, the ECU performs feedback control on the opening of the flow regulating valve based on the final opening. As a result, the responsibility of the coolant temperature control is improved.

Abstract: An engine thermal management system and method for a vehicle engine that allows for reduced coolant flow and energy consumption by the system, while avoiding excessive critical metal temperatures in the engine. The engine includes a coolant inlet in a head and a coolant outlet in a block. A variable speed pump pushes the coolant into the head inlet. A multi-port valve receives the coolant exiting the engine block and selectively routes it to various system components. The speed of the pump and the valve are electronically controlled by a control module, based upon various engine and vehicle operating conditions.

Abstract: A snowmobile having a liquid-cooled engine with an improved cooling system is disclosed. The engine is connected between the inlets and outlets of first and second coolant circuits that are each comprised of one or more interconnected heat exchangers. The coolant circuits circulate coolant pumped from the engine and dissipate heat generated by the engine during its operation. A thermostat valve is operatively connected to one of the second coolant circuit and blocks coolant flow in the circuit when the engine temperature is below a threshold level. The first coolant circuit provides the main cooling circuit for the engine. The second cooling circuit provides a parallel cooling path that enhances the cooling capacity of the cooling system when the engine temperature exceeds the threshold.

Abstract: The invention concerns a method for regulating the temperature of an engine, in particular an internal combustion engine 12, in the case of which the engine is interconnected with a radiator 16 via at least one forward-delivery line 35 and at least one return-delivery line 44 within a cooling circuit 14, which said radiator can be bypassed via a valve-controlled bypass line 48 between the at least one forward-delivery line 35 and the at least one return-delivery line 44. Additionally, the cooling circuit 14 comprises at least one pump capable of being controlled via open-loop and/or closed-loop control, in particular an electric pump 34 for pumping a coolant through the connecting lines 32 of the cooling circuit 14, as well as an electronic control unit 52 that controls the cooling capacity of the cooling circuit 14 via open-loop and/or closed-loop control.

Abstract: An engine cooling system controls a cooling degree of an engine 1 according to an operating condition thereof by circulating cooling water through the engine. This system is provided with a flow rate regulating valve 8 for regulating a circulation flow rate of the cooling water. An electronic control unit (ECU) 30 controls the valve 8 to open at a predetermined opening when determining the engine 1 as being stopped. In this opening control, the ECU 30 controls to bring a valve element into contact with a valve body once and then move the valve element to determine the predetermined opening with reference to a full-closed position of the valve element.

Abstract: In a case where no malfunction occurs in a water temperature control valve the temperature of the pump water is controlled to accurately follow a target water temperature. In contrast, in a case where the rotational opening degree of the water temperature control valve is accidentally fixed, the pump water temperature can no longer follow the target water temperature. In this instance, a control water temperature error between the target water temperature and the pump water temperature is calculated. When the control water temperature error is greater than a certain error range, a counter is incremented, and a malfunction judgment flag is set when the value of the counter exceeds a certain judgment threshold value at another time. Thereby, the temperature of the cooling water for the engine is feedback controlled while malfunction of the water temperature control valve can be accurately detected.

Abstract: An engine cooling system and method applicable to a diesel engine in a vehicle. A control module, via a single multi-port valve, controls the coolant flow through a radiator, heater and oil cooler based upon engine operating conditions.

Abstract: A flow control valve is located in a coolant circuit that extends through an engine. The flow control valve is operated in accordance with a control mode selected from a full closing control mode, a full opening control mode, and a feedback control mode. When switching from one control mode to another, the flow control valve is controlled in accordance with a transitional control procedure selected from different types of transitional control procedures. The transitional control procedure to be performed is selected depending on which control modes are performed before and after the control mode switching and/or the current condition of the engine. Transitional controlling of the flow control valve is thus appropriately conducted.

Abstract: An engine having an electronic engine control unit (ECU) is provided with a temperature management system for the ECU to prevent failure of the ECU through overheating. The temperature management system comprising means for monitoring or evaluating the temperature of the ECU to determine when the temperature of the ECU is approaching a predetermined limit and means for limiting further heating of the ECU to prevent the said limit from being exceeded.

Abstract: In a cooling arrangement for a water-cooled snowmobile engine, a water pump is disposed on the front side of the cylinder head, under the exhaust manifold and is coupled to a crankshaft so that it is driven by the rotational force which is transmitted through a drive belt from a drive pulley fitted on the crankshaft end. A cooling water inlet port for leading cooling water into the interior of the engine is provided on the front side of the cylinder block and under the exhaust manifold while a cooling water outlet port through which cooling water is taken out from the interior of the engine is arranged on the cylinder head's side face at a position over and opposite to the drive belt and a thermostat is arranged at the cooling water outlet port.

Abstract: A cooling system for an internal combustion engine with at least two cylinder rows, in particular for a V-engine for a motor vehicle, has a coolant radiator and a thermostat valve for controlling a flow of coolant from coolant outlets of the cylinder rows, through or bypassing the coolant radiator, and back to the coolant inlets of the cylinder rows. The coolant outlet of one of the cylinder rows is directly connected with an inlet of the coolant radiator, and the coolant outlet of another cylinder row is directly connected with a bypass inlet of the thermostat valve. A bi-directional intermediate line is arranged between the bypass inlet of the thermostat valve and the inlet of the coolant radiator.

Abstract: A method for cooling a motor vehicle engine consists in regulating the volume and the flow rate of a coolant fluid in a hydraulic circuit provided with a branch equipped with an electronically controlled actuator and means forming radiator. The method comprises a step of determining the temperature of the cooling liquid, a step of comparing the temperature of the cooling liquid with a specified threshold temperature from which the engine is said to be hot, and, when the temperature of the fluid is higher than the threshold temperature, the flow rate in the radiator branch is regulated so as to maintain the temperature of the cooling fluid around a specified setpoint value. The curve representing the opening of the thermostat valve based on the temperature of the cooling fluid exhibits an hysteresis around the setpoint temperature. The invention also concerns a device for cooling a motor vehicle engine.

Abstract: An automatic heat exchanger tempering valve designed to maintain a consistent temperature of a fluid within a machine. The tempering valve is configured to sense fluid temperature and in response, to proportion the flow of the fluid from the machine between a heat exchanger and an either internal or external by-pass flow circuit. The valve includes a movable valve diverter positionable in multiple positions to create a variety of proportionate flows of the total fluid flow stream between the heat exchanger and the by-pass flow circuit. The valve diverter is positioned by a multiple position valve actuator that changes the position of the diverter by reacting to a change in fluid temperature. The valve and the bypass flow circuit are easily installed within a motor vehicle by simply splicing into the two radiator hoses in the engine compartment.

Abstract: The present invention relates to a water-type cooling unit for a vehicle equipped with an internal-combustion engine, the unit being connected via a main circulation loop formed by appropriate conduits, in particular to at least one radiator for cooling the water or the similar coolant and to the circuits for cooling the cylinder block and the cylinder heads. Unit, characterized in that it comprises a central module in the form of a body made of thermoplastic material in which there are, in particular, mounted or partially molded a water-circulating pump and a flow-regulating valve disposed in the circulating loop, preferably between the aforementioned cooling circuits and the radiator.

Abstract: A thermostatic valve for a coolant circuit of an internal combustion engine, with a housing through which the flow is capable of passing and which has a first throughflow orifice for connection to a first coolant line, a second throughflow orifice for connection to a second coolant line, and a third throughflow orifice for connection to a third coolant line, and with a closure member which is mounted in the housing and which can be adjusted by an actuating unit, the closure member having a first shut-off element for shutting off the first throughflow orifice and a second shut-off element, coupled to the first shut-off element, for shutting off the second throughflow orifice.

Abstract: Improved internal combustion engine, particularly, an improved two-stroke, diesel aircraft engine. A first improvement includes a wrist pin/connection rod assembly. A plurality of fasteners extend through a wall of a wrist pin and into a wrist pin insert to secure the wrist pin to a cradle-like portion of a connecting rod. A second improvement includes a fuel injection system which cools fuel injectors with overflow fuel from a fuel pump. The overflow fuel is warmed as it cools the fuel injectors, thereby preventing ice-build up on a fuel filter in cold weather as the overflow fuel is recirculated to the fuel pump. A third improvement includes a new cylinder head cooling arrangement. The cylinder head and a cooling cap define an annular cooling passageway. Cooling fluid flows through the annular cooling passageway to cool the cylinder head. The cooling cap includes an inlet port and an outlet port which are not diametrically opposed.

Abstract: An engine cooling system for an all-terrain vehicle provided with a front fender (12), and an engine (3) provided with water jackets and mounted on a body frame (F) at a position between front and rear wheels includes a radiator (45) provided with a water inlet (54) and disposed in a front part of the body frame (F), a water filling cup (16) provided with a water filling opening (16a), and a thermostat case (17) holding a thermostat (17a) therein. The water filling cup (16) is separated from the radiator (45). The water filling cup (16) and the thermostat case (17) are placed in a part of a connecting pipe connecting the water inlet(54) of the radiator (45) and the outlets (57, 58) of the water jackets of the engine (3) at the highest level in a cooling water circulating passage. A protruded portion (18) is formed on the front fender (12) so as to surround a steering shaft, and the water filling cup (16) and the thermostat case (17) are placed inside the protruded portion (18).

Abstract: In a case where no malfunction occurs in a water temperature control valve the temperature of the pump water is controlled to accurately follow a target water temperature. In contrast, in a case where the rotational opening degree of the water temperature control valve is accidentally fixed, the pump water temperature can no longer follow the target water temperature. In this instance, a control water temperature error between the target water temperature and the pump water temperature is calculated. When the control water temperature error is greater than a certain error range, a counter is incremented, and a malfunction judgment flag is set when the value of the counter exceeds a certain judgment threshold value at another time. Thereby, the temperature of the cooling water for the engine is feedback controlled while malfunction of the water temperature control valve can be accurately detected.

Abstract: A cooling system for an internal combustion engine includes a radiator provided in a coolant circulation path of the internal combustion engine, and an actuator that controls a flow rate of a coolant that passes through the radiator. In the cooling system, the actuator is controlled so that a coolant temperature of the engine becomes substantially equal to a target coolant temperature. The cooling system calculates a cooling loss as a quantity of heat removed from the engine by the coolant, based on an operating state of the engine, and calculates a required radiator flow rate, based on the cooling loss, the target coolant temperature, and a temperature of the coolant that has passed through the radiator. The required radiator flow rate represents a quantity of the coolant required to pass through the radiator so as to achieve the target coolant temperature. The cooling system then controls the actuator based on the required radiator flow rate.

Abstract: In a thermoset valve for a cooling circuit of an internal combustion engine of the type having a housing (11) containing a thermostatic operating element (10) whose piston (12) actuates a valve element (13), a base plate (17) is affixed to the housing (11) and supports a fixed abutment (25) for a restoring spring (24) which loads the valve element (13).

Abstract: An apparatus for controlling a temperature of an engine by controlling the flow of a liquid engine coolant to a radiator is disclosed. The apparatus includes a thermostat having a thermally responsive valve for substantially blocking or opening the flow of coolant to the radiator to maintain the engine at or about a preferred engine operating temperature. Also included is a thermally activated actuator for opening the valve in response to an engine condition such as load or a need for power. The actuator is activated at a temperature different than the thermostat. A source of electro thermal energy is provided to motivate the actuator so the valve may be opened on demand. In one aspect the invention provides a method of controlling the temperature of the engine by opening the valve in response to engine monitoring.