Internal combustion engine with piston cooling jets

Abstract

Internal combustion engine (ICE) (10), comprising: an engine block (12) which includes a plurality of cylinders (20a, 20b, 20c, 20d), a piston (22a, 22b, 22c, 22d) arranged in each of the plurality of cylinders (20a, 20b, 20c, 20d); and a piston cooling jet (PCJ) (30a, 30b, 30c, 30d) which is attached to direct a coolant flow onto the piston (22a, 22b, 22c, 22d) in each of the plurality of cylinders (20a, 20b, 20c, 20d), wherein the PCJ (30a, 30b, 30c, 30d) includes an inlet (56), an outlet (58) and a controlled flow passage (60) which allows a substantially continuous coolant flow to flow from the inlet (56) to the outlet (58); wherein the PCJ (30a, 30b, 30c, 30d) comprises an actuator element (80) that selectively switches between a closed configuration and an open configuration, allowing a coolant jet to flow onto the piston (22a, 22b, 22c, 22d); wherein the controlled flow passage (60) comprises a plurality of controlled flow passages (84); wherein the multitude of controlled flow passages (84) extends around a circumference of the actuator element (80).

Description

INTRODUCTION

[0001] The present disclosure relates to the field of motor vehicles and, more particularly, to a motor vehicle having an internal combustion engine having a piston cooling jet (PCJ).

[0002] Internal combustion engines (ICEs) rely on pistons to drive a crankshaft coupled to a flywheel. The flywheel is typically mechanically connected to drive one or more vehicle wheels through a transmission. The piston moves within a cylinder and is powered by combustion products produced by the ignition of a fuel such as gasoline, diesel fuel, and the like. The combustion products generate heat, which is absorbed by many components of the ICE, including the pistons. Due to the heat effect, pistons are typically constructed of heat-conducting materials such as aluminum.

[0003] Currently, manufacturers use higher-strength materials in the formation of pistons. Higher-strength materials, such as steel, can withstand higher engine load requirements imposed by, for example, start-stop systems, selective cylinder locking systems, and the like. While these higher-strength materials possess properties desirable for higher stresses, they also exhibit lower thermal conductivity. This lower thermal conductivity makes heat dissipation more difficult with conventional systems.

[0004] US 2006 / 0 243 226 A1 describes a device for supplying cooling and lubricating fluid to cooling and lubricating nozzles for the pistons of an internal combustion engine, comprising at least one valve with an upstream channel and a downstream channel, wherein the valve has a blocking element that can move within a space for blocking and opening. The valve responds to the pressure of the cooling fluid by opening when the upstream pressure is greater than a threshold pressure and closing when the upstream pressure is less than the threshold pressure. A calibrated leakage means connects the upstream channel to the downstream channel parallel to the valve's closure zone.

[0005] DE 10 2012 212 597 A1 describes an oil spray device comprising a housing in fluid communication with a source of oil pressure, a first nozzle in fluid communication with the housing, and a second nozzle in fluid communication with the housing. The oil spray device also comprises a mechanism arranged within the housing and configured to open the first nozzle and close the second nozzle when the oil pressure is below a threshold value. The mechanism is also configured to open the second nozzle and close the first nozzle when the oil pressure is at or above the threshold value. An engine comprising a cylinder defined by a cylinder bore, a piston configured to reciprocate within the cylinder bore, and the oil spray device, together with a vehicle having such an engine, is also described.In the engine, the first nozzle sprays oil onto the cylinder bore and the second nozzle sprays oil onto the underside of the piston.

[0006] DE 31 49 604 A1 describes a hydraulic piston valve that operates with vibration damping and without pressure peaks. For this purpose, the spring-loaded piston has a throttle bore that continuously connects the valve inlet opening to the spring chamber. Furthermore, a continuous flow (bores) from the spring chamber to the valve outlet opening is ensured.

[0007] US 2016 / 0 047 290 A1 describes a device for controlling the supply of a fluid to a system by which the fluid consumption can be optimized, for example a device for controlling the oil supply to piston cooling spray nozzles in an internal combustion engine.

[0008] Accordingly, it is desirable to provide a system for heat dissipation from pistons, particularly those formed from materials with lower thermal conductivity than aluminum. SUMMARY

[0009] Disclosed is an internal combustion engine (ICE) having an engine block including a plurality of cylinders, a piston disposed in each of the plurality of cylinders, and a piston cooling jet (PCJ) mounted to direct a flow of coolant onto the piston in each of the plurality of cylinders. The PCJ includes an inlet, an outlet, and a controlled flow passage such that a substantially continuous flow of coolant can pass from the inlet to the outlet.

[0010] According to the invention, the PCJ includes an actuator element that selectively switches between a closed configuration and an open configuration so that a coolant jet can flow onto the piston.

[0011] In addition to, or alternatively to, one or more of the features described above or below, further embodiments may be included wherein the PCJ includes a spring that biases the actuator element toward the closed configuration.

[0012] According to the invention, the controlled flow passage comprises a plurality of controlled flow passages.

[0013] According to the invention, the plurality of controlled flow passages extend around a circumference of the actuator element.

[0014] In addition to, or alternatively, one or more of the features described above or below, further embodiments may be included wherein the plurality of controlled flow passages together define an equivalent hydraulic diameter of between about 1 mm and about 4 mm.

[0015] Also disclosed is a method for cooling a piston in an internal combustion engine (ICE), including activating a controller to deliver a coolant pulse to a piston cooling jet (PCJ), directing the coolant pulse onto the piston, and directing a continuous flow of coolant to the piston through the PCJ.

[0016] In addition to, or alternatively to, one or more of the features described above or below, further embodiments may be included wherein directing the coolant pulse includes biasing an actuator element of the PCJ with a pressure of the coolant pulse.

[0017] According to the invention, directing the coolant flow through the controlled flow channel comprises directing the coolant flow through a plurality of controlled passages.

[0018] In addition to, or alternatively to, one or more of the features described above or below, further embodiments may be included wherein directing the coolant flow through a plurality of controlled flow passages includes directing the coolant flow through a plurality of controlled flow passages having a common equivalent hydraulic diameter between about 1 mm and about 4 mm.

[0019] The above features and advantages and other features and advantages of the disclosure will be readily apparent from the following detailed description when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Other features, advantages and details appear only by way of example in the following detailed description, which makes reference to the drawings in which: Fig. 1 is a schematic view of an internal combustion engine including piston cooling jets according to one aspect of an embodiment; Fig. 2 is a cross-sectional side view of a portion of the internal combustion engine of Fig. 1, according to one aspect of an embodiment; Fig. 3 is a perspective view of a piston cooling jet for better understanding; Fig. 4 is a cross-sectional side view of the piston cooling jet of Fig. 3, which serves for better understanding; Fig. 5 is a cross-sectional side view of a piston cooling jet according to the invention; and Fig. 6 represents an actuator of the piston cooling jet of Fig. 5, according to the invention. DETAILED DESCRIPTION

[0021] The following description is merely exemplary in nature and is not intended to limit the present disclosure, its application, or uses. It should be understood that throughout the drawings, corresponding reference characters indicate like or corresponding parts and features.

[0022] An internal combustion engine (ICE), according to one embodiment, is generally shown at 10 in the Fig. 1 and Fig. 2. The ICE 10 includes an engine block 12 supporting an intake manifold (not shown) and an exhaust manifold 16. The intake manifold and exhaust manifold 16 may be connected to a turbocharger (also not shown). The engine block 12 includes a plurality of cylinders 20a, 20b, 20c, and 20d housing a corresponding plurality of pistons 22a, 22b, 22c, and 22d. The pistons 22a-22d move within the engine block 12 in response to combustion events during the combustion of fuel and air. The combustion events generate heat.

[0023] According to one embodiment, the engine block 12 supports a plurality of piston cooling jets (PCJs) 30a, 30b, 30c, and 30d that operate to deliver coolant to corresponding ones of the pistons 22a-22d. Each PCJ 30a-30d is fluidly connected to a coolant manifold 34, which is connected to a coolant supply 36. The coolant supply 36, in one exemplary aspect, stores a quantity of lubricant 38, such as oil. A control valve 40 is disposed between the coolant supply 36 and the coolant manifold 34.

[0024] A first passage or conduit 42 connects the control valve 40 and the coolant manifold 34. The first passage 42 can selectively deliver a pulse of coolant into the coolant manifold 34, which is routed to each PCJ 30a-30d. A second passage or conduit 44 also connects the control valve 40 and the coolant manifold 34. The second conduit 44 can include a one-way valve 46 that ensures that the coolant does not flow from the coolant manifold 34 back to the control valve 40 via the second conduit 44. The second conduit 44 allows a continuous supply of coolant to flow into the coolant manifold 34. The continuous supply of coolant ensures that regardless of a position of the control valve 40, a controlled amount of coolant will continuously flow through each PCJ 30a-30d.

[0025] Reference is now made to the Fig. 3 and Fig. 4, wherein PCJ 30a is described with the understanding that PCJs 30b-30d may include a similar structure. PCJ 30a includes a jet body 54 having an inlet 56, an outlet 58, and a flow passage 60 ( Fig. 4) extending therebetween. An actuator element 64 is disposed in the flow passage 60 and is selectively activated by a momentary increase in coolant pressure generated by the control valve 40. The momentary increase, or "pulse," in coolant pressure causes a quantity of coolant, such as the lubricant 38, to flow from the inlet 56 and be discharged through the outlet 58. A biasing element, such as a spring 66, is disposed in the flow passage 60 to bias the actuator element 64 toward a closed configuration.

[0026] In one exemplary aspect, actuator element 64 includes a controlled flow passage 70. Controlled flow passage 70 allows a continuously controlled amount of coolant to flow through PCJ 30a, even when actuator element 64 is biased toward the closed position. The continuous coolant flow is directed onto piston 22a to promote additional heat dissipation, which extends overall service life. In one embodiment, controlled flow passage 70 includes an equivalent hydraulic diameter between about 1 mm and about 4 mm.

[0027] Reference is now made to the Fig. 5 and Fig.6, wherein an actuator element 80 is described according to another aspect of an embodiment. The actuator element 80 includes a plurality of controlled flow passages 84. The plurality of controlled flow passages 84 extend through the actuator element 80. In particular, the plurality of controlled flow passages extend around a circumference and through a top or crown portion 88 of the actuator element 80.

[0028] The plurality of controlled flow passages 84 allows a continuously controlled amount of coolant to flow through PCJ 30a, even when actuator element 80 is biased toward the closed position. The continuous coolant flow is directed onto piston 22a to promote additional heat dissipation to extend overall service life. In one embodiment, the plurality of controlled flow passages 84 together encompass an equivalent hydraulic diameter of between about 1 mm and about 4 mm.

[0029] The terms "about" and "substantially" are intended to encompass the degree of error associated with measuring the respective quantity based on the equipment available at the time the application is filed. For example, "about" and "substantially" may include a range of ± 8%, 5%, or 2% of a given value.

[0030] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It is further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0031] While the above disclosure has been described with reference to exemplary embodiments, those skilled in the art will understand that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope thereof. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from the essential scope thereof. Therefore, the present disclosure is not intended to be limited to the particular embodiments disclosed, but is intended to include all embodiments falling within the scope thereof.

Claims

[1] Internal combustion engine (ICE) (10), comprising: an engine block (12) including a plurality of cylinders (20a, 20b, 20c, 20d), a piston (22a, 22b, 22c, 22d) disposed in each of the plurality of cylinders (20a, 20b, 20c, 20d); and a piston cooling jet (PCJ) (30a, 30b, 30c, 30d) mounted to direct a flow of coolant onto the piston (22a, 22b, 22c, 22d) in each of the plurality of cylinders (20a, 20b, 20c, 20d), the PCJ (30a, 30b, 30c, 30d) including an inlet (56), an outlet (58), and a controlled flow passage (60) allowing a substantially continuous flow of coolant to flow from the inlet (56) to the outlet (58); wherein the PCJ (30a, 30b, 30c, 30d) comprises an actuator element (80) that selectively changes between a closed configuration and an open configuration so that a coolant jet can flow onto the piston (22a, 22b, 22c, 22d); wherein the controlled flow passage (60) comprises a plurality of controlled flow passages (84); wherein the plurality of controlled flow passages (84) extend around a circumference of the actuator element (80). [2] The ICE (10) of claim 1, wherein the PCJ (30a, 30b, 30c, 30d) includes a spring (66) biasing the actuator element (80) toward the closed configuration. [3] The ICE (10) of claim 1, wherein the plurality of controlled flow passages (84) together define an equivalent hydraulic diameter between about 1 mm and about 4 mm. [4] A method for cooling a piston (22a, 22b, 22c, 22d) in an internal combustion engine (ICE) (10), comprising: activating a controller to deliver a coolant pulse to a piston cooling jet (PCJ); Directing the coolant jet onto the piston (22a, 22b, 22c, 22d); and Directing a continuous flow of coolant to the piston (22a, 22b, 22c, 22d) through the PCJ (30a, 30b, 30c, 30d); wherein the PCJ (30a, 30b, 30c, 30d) comprises an actuator element (80) that selectively changes between a closed configuration and an open configuration so that a coolant jet can flow onto the piston (22a, 22b, 22c, 22d); wherein the PCJ (30a, 30b, 30c, 30d) comprises an inlet (56), an outlet (58) and a controlled flow passage (60) allowing the continuous coolant stream to flow from the inlet (56) to the outlet (58); wherein the controlled flow passage (60) comprises a plurality of controlled flow passages (84); wherein the plurality of controlled flow passages (84) extend around a circumference of the actuator element (80). [5] The method of claim 4, wherein directing the continuous coolant flow includes directing a coolant flow through a controlled flow passage (60) defined by the actuator element (80).

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