CN110656997A - Engine compression release brake and engine using same - Google Patents

Abstract

Conventional engine compression release braking systems include an engine brake associated with each cylinder of the engine. However, if the maximum brake horsepower required by the engine is less than the maximum brake horsepower developed using all of the engine cylinders, the engine includes redundant components. To reduce the number of engine components and thus increase engine robustness, the present invention includes an engine compression release braking system that provides a plurality of engine brakes less than the total number of engine cylinders.

Description

Engine compression release brake and engine using same

Technical Field

The present invention relates generally to engine compression release brakes and more particularly to engines having engine compression release brakes with less than all of the engine cylinders.

Background

Conventional engine compression release brake systems typically include an engine brake for each engine cylinder. One such engine compression-release braking system is shown in the U.S. PAT. 5647318 to Feucht et al. 1997, 7, 15 days. In the braking system disclosed by Feucht et al, the brake horsepower is varied by operating less than all of the engine brakes. However, if the maximum brake horsepower required by the system does not require engine braking using all of the engine cylinders, the engine includes redundant components. Engineers have recognized that reducing engine components, such as removing redundant components, can improve the overall robustness of the engine. Accordingly, it should be appreciated that it is desirable for an engine compression-release brake system to include a sufficient, but reduced, number of components.

Disclosure of Invention

The object of the present invention is to overcome the above-mentioned drawbacks of the prior art and to provide a method for detecting a low starting intensity of a battery of an internal combustion engine during an engine start, which is able to overcome the false effects of detecting and analyzing a variation in the voltage of the battery caused by random and/or periodic electromechanical noise. Vibrations associated with engine starting.

The technical scheme of the invention is as follows: an engine, an engine housing defining a plurality of engine cylinders; and an engine compression release brake for each of a portion of the engine cylinders, wherein the portion is less than all of the plurality of engine cylinders; each said engine compression-release brake being alternately fluidly connected to a high pressure fluid source and a low pressure reservoir; each of the engine compression release brakes includes an electric actuator; a cam actuated exhaust valve comprising each engine cylinder; each said engine compression release brake including a hydraulic piston operatively connected to an exhaust valve actuator movably positioned in said exhaust valve; a lash adjuster operatively connected to the hydraulic piston; each said engine compression release brake including at least one valve member; at least one valve member comprises a spool valve member; the spool valve member includes a first hydraulic surface opposite a second hydraulic surface; each said engine compression release brake including at least one valve member; the at least one valve member comprises a spool valve member; the spool valve member includes a first hydraulic surface opposite a second hydraulic surface.

An engine braking method using less than all of the engine cylinders, attaching an engine compression release brake to an engine housing such that each portion of the engine cylinders is smaller than each portion of the engine cylinders, and operating each portion of the engine cylinders in a braking mode; said operating said portion of said engine cylinder in a braking mode comprises the step of exposing a hydraulic surface of a piston to a high pressure actuating fluid; the step of operating the portion of the engine cylinder in the braking mode includes the step of energizing at least one electric actuator operatively connected to the engine compression release brake.

The invention has the beneficial effects that: accurate, reliable, relatively simple and inexpensive implementation in various internal combustion engines.

Drawings

FIG. 1 is a schematic view of an engine of the modular engine compression-release brake system of the present invention.

Detailed Description

In fig. 1, a low pressure accumulator 12 is provided in an engine 1, and a high pressure pump 13 pumps oil from the low pressure accumulator 12 and delivers it to a high pressure manifold 14. The high-pressure oil flowing out of the high-pressure manifold 14 is delivered to a hydraulic system provided in the engine 10 through a high-pressure fluid supply line 15, and after performing work in the hydraulic system, the old oil is returned to the low-pressure reservoir tank 12 through a low-pressure return line 16. An electronic control module 17 is provided by the engine 10 and is in control communication with one or more engine components via an electronic communication line 18. The electronic control module 17 preferably controls various aspects of engine operation, such as fuel injection timing and engine compression release brake timing. The engine 10 also provides an engine housing 11 defining a plurality of engine cylinders 20. Each cylinder 20 defined by the engine housing 11 has a movable piston 21. Each piston 21 is movable between a retracted, downward position and an advanced, upward position. For a typical four cycle diesel engine 10, the advancing and retracting strokes of the piston 21 correspond to four phases of operation of the engine 10. When the piston 21 first retracts from its top dead center position to its bottom dead center position, the piston is undergoing an intake stroke and air may be drawn into the cylinder 20 through the intake valve. When the piston 21 is advanced from its bottom dead center position to its top dead center position, the piston is undergoing a compression stroke and the air within the cylinder 20 is compressed. At the end of the compression stroke, fuel may be injected into the cylinder 20 through the fuel injector 30, and combustion within the cylinder 20 may occur instantaneously due to the high temperature of the compressed air. This combustion drives the piston 21 downward toward its bottom dead center position for the power stroke of the piston 21. However, it is known in the art that injection and combustion are not always necessary, or desirable, during each cycle of the piston 21. Thus, engine compression-release braking may occur within engine 10 for these engine cycles, as described below. Finally, as the piston 21 again advances from its bottom dead center position to its top dead center position, the remaining post-combustion products in the cylinder 20 may be exhausted through the cam-driven exhaust valve 35, corresponding to the exhaust stroke of the piston 21. While engine 10 has been illustrated as a four-cycle, six-cylinder engine, it should be appreciated that any desired number of cylinders may be defined by engine housing 11. Each cylinder 20 is operatively connected to a plurality of hydraulic and/or mechanical actuation means. In addition to the hydraulically actuated fuel injectors 30 and the cam actuated exhaust valves 35 shown in FIG. 1, other devices are operatively connected to each cylinder 20, such as intake valves. The fuel injectors 30 are fluidly connected to a fuel source 31 via fuel supply lines 32 and deliver fuel to the cylinders 20 for combustion, while exhaust valves 35 control the release of combustion residuals after each injection event. In addition, a portion, but not all, of the cylinders 20 each include a hydraulically actuated engine compression release brake 40 operatively connected to the exhaust valves 35 of the cylinders 20. Although engine 10 has been shown with engine compression release brake 40 connected to four cylinders 20, it should be understood that engine compression release brake 40 may alternatively be connected to any suitable number of engine cylinders 20 less than the total number of cylinders. S20 is defined by the engine case 11.

Claims (2)

1. An engine, characterized in that: an engine housing defining a plurality of engine cylinders; and an engine compression release brake for each of a portion of the engine cylinders, wherein the portion is less than all of the plurality of engine cylinders; each said engine compression-release brake being alternately fluidly connected to a high pressure fluid source and a low pressure reservoir; each of the engine compression release brakes includes an electric actuator; a cam actuated exhaust valve comprising each engine cylinder; each said engine compression release brake including a hydraulic piston operatively connected to an exhaust valve actuator movably positioned in said exhaust valve; a lash adjuster operatively connected to the hydraulic piston; each said engine compression release brake including at least one valve member; at least one valve member comprises a spool valve member; the spool valve member includes a first hydraulic surface opposite a second hydraulic surface; each said engine compression release brake including at least one valve member; the at least one valve member comprises a spool valve member; the spool valve member includes a first hydraulic surface opposite a second hydraulic surface.

2. An engine braking method using less than all of the engine cylinders, comprising the steps of: connecting an engine compression release brake to an engine housing such that each portion of the engine cylinder is smaller than each portion of the engine cylinder and operating each portion of the engine cylinder in a braking mode; said operating said portion of said engine cylinder in a braking mode comprises the step of exposing a hydraulic surface of a piston to a high pressure actuating fluid; the step of operating the portion of the engine cylinder in the braking mode includes the step of energizing at least one electric actuator operatively connected to the engine compression release brake.

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