Corresponding reference characters indicate corresponding parts throughout the drawings.
As shown in
In one embodiment, the engines 104, 106 are operated in response to a throttle position input sensor 112 (or an rpm sensor) which indicates the position of the throttle as controlled by the operator. In addition, there may be an optional operator engine start input 114 where the operator can directly or indirectly instruct the controller 102 (e.g., via a keypad) with regard to operation of the engines or termination of operation of the engines. In addition, a vehicle speed sensor 116 for indicating vehicle speed and/or a direction input sensor 118 for indicating desired direction of movement of the vehicle 100 may provide information to the controller 102.
In an embodiment when the first and second engines are not operating, the controller 102 will initiate operation of the first engine 104 when the throttle position input sensor 112 indicates that the throttle has been moved by the operator from one position (e.g., an idle position) to a position which requires additional power. For example, off-highway vehicles frequently have throttles with a notch positions idle, and 1-9 and controller 102 would initiate operation of the first engine 104 by signaling the engine start and stop control 108 when the throttle position sensor 112 senses movement of the throttle from position idle to position 1. As described herein, embodiment of the invention will be presented with reference to throttle notch positions. However, it is contemplated that any type of throttle configuration may be used in combination with embodiments of the invention.
In an embodiment when the first engine 104 of the off-highway vehicle 100 is operating and the second engine 106 is not operating, the operation of the second engine will be initiated by the controller 102 via engine control 108 when a set of operating conditions with regard to the first engine are met. As illustrated in
In particular, a flow chart illustrated in
In summary, as illustrated in
As illustrated in
Thus, embodiments of the invention increase fuel economy by minimizing, to some extent, the operation of the second engine when the first engine has sufficient output to manage the requirements of the vehicle. Other embodiments of the invention, such as illustrated in
Other embodiments relate to control of the revolutions per minute of the second engine 206 when operating simultaneously with first engine 104. In one embodiment, the controller 102 increases the revolutions per minute of the second engine 106 to a predetermined revolutions per minute (e.g., from 0 to 1500) and decreases the revolutions per minute of the first engine to a predetermined revolutions per minute (e.g., from 1800 to 1500). This approach may be used when the engines are in parallel. Alternatively, in another embodiment, the controller may maintain the revolutions per minute of the first engine 104 and increase the revolutions per minute of the second engine 106 to a predetermined revolutions per minute. This approach may be used when the engines are in series.
Other embodiments relate to stopping the second or an additional engine and/or eventually stopping the first or primary engine. For example, stopping the second engine may be implemented in response to an operator reducing a throttle position of the vehicle 100 to a predetermined amount such as moving the throttle from notch 3 to notch 2. In response to a reduced throttle position or any other detected condition of the off-highway vehicle which would indicate a reduction in power needs, the controller 102 reduces the revolutions per minute of the second engine 106 to an idle setting and thereafter controls the revolutions per minute of the second engine 106 as a function of the throttle position. For example, the second engine may not be increased in speed as long as the throttle remains at a particular setting (e.g., idle) or below a particular setting. While the second engine 106 is at idle, the controller 102 controls the revolutions per minute of the first engine as a function of the throttle position. Alternatively, and in addition, it is contemplated in one embodiment of the invention that the controller 102 may stop the second engine 106 after a predetermined period of time during which the second engine has been idle.
Thus, one embodiment of the invention as illustrated by
a throttle position of the off-highway vehicle 100 as indicated by the throttle sensor 112 is greater than a predetermined throttle position;
a speed of the off-highway vehicle as indicated by the speed sensor 116 is greater than a predetermined speed; and
the first engine 104 is operating at an output level greater than a predetermined output level, as indicated by the traction bus sensors 128, 130 and the auxiliary bus sensors 132, 134.
Alternatively, if the second engine rpms have increased above idle as determined at 316, the controller proceeds to 302 and continues operation of the second engine. For example, an increase in throttle position to notch 5 or above, at a speed above 4 mph with the first engine operating over 90% of its rated output, per
Alternatively, the controller 102 may be configured to immediately increase the revolutions per minute of the second engine above an idle setting as a function of the throttle position. For example, any increase in the notch setting of the throttle would be implemented to include an increase in the revolutions per minute of the second engine 106. Once the second engine has stopped at 314, the controller may implement the control scenario of
Alternatively, or in addition, the controller may implement a scenario to shut down the first or primary engine 104. In one embodiment, the controller 102 stops operation of the first engine after a predetermined period of idling of the first engine (e.g., 1 hour) when any one or more of the following conditions are present for a predetermined period (e.g., 15 minutes):
a sensor 120 indicating to the controller 102 that a battery charging current being applied to a battery is less than a predetermined battery charging current (e.g., 20 amperes, indicating a charged battery);
a sensor 122 indicating to the controller 102 that a battery voltage is greater than a predetermined battery voltage (e.g., 69 volts, indicating a charged battery);
a sensor 124 indicating to the controller 102 that an ambient air temperature is greater than a predetermined ambient air temperature (e.g., 10 degrees Fahrenheit, indicating no need for auxiliary heating)
the sensor 118 indicating to the controller 102 that a direction input in neutral (indicating no demand for directional movement); and/or
a sensor 126 indicating to the controller 102 that a brake cylinder pressure above a predetermined brake cylinder pressure (e.g., 22 psi, indicating sufficient operating pressure for the brakes).
Alternatively, in addition, the controller 102 may implement shut down of the primary engine only when all five of the above noted conditions are met simultaneously throughout a predetermined period of time. In another embodiment, the controller may shut down the primary engine when the revolutions per minute of the primary engine reaches an idle setting and is reset only if the revolutions per minute of the primary engine increases above the revolutions per minute corresponding to idle. Alternatively, in another embodiment, the controller may begin the predetermined period of idling when the throttle position is in a position corresponding to idle and the direction position in neutral, and such a period of time can only be reset if the revolutions per minute of the first engine increase above the revolutions per minute corresponding to idle. In addition, the controller may determine when the vehicle produces no substantial motive force and may shut down the air conditioning system (driven by the auxiliary bus) of the off-highway vehicle after a predetermined period of time of vehicle idling time with no substantial motive force.
Thus, one embodiment of the invention as illustrated in
In another embodiment of the invention, transitioning the first or primary engine from an idle condition to an operating condition, and/or transitioning from idle to stop, may also be controlled by the controller 102. In one embodiment, one or more of the engines 104, 106 are started by the controller 102 in response to any one or more of the following conditions: (1) a battery voltage is less than a predetermined first battery voltage (e.g., 60 volts);
(2) an ambient air temperature is less than a predetermined first ambient air temperature (e.g., zero degrees Fahrenheit);
(3) a direction input is changed from neutral to either forward or reverse;
(4) a brake cylinder pressure is below a predetermined first brake cylinder pressure (e.g., 18.5 psi); and/or
(5) an engine start input is activated by an operator via input 114.
In one embodiment, the engine is stopped in response to any one or more of the following conditions:
(1) a battery charging current is less than a predetermined battery charging current (e.g., 20 amperes);
(2) a battery voltage is greater than a predetermined second battery voltage (e.g., 69 volts);
(3) an ambient air temperature is greater than a predetermined second ambient air temperature (e.g., 10 degrees Fahrenheit);
(4) a direction input is in neutral; and/or (5) a brake cylinder pressure is above a predetermined second brake cylinder pressure (e.g., 22 psi).
Alternatively or in addition, the air conditioning system of the off-highway vehicle may be shut down after a predetermined period of time (e.g., 1 hour) during which the engine or engines are in the idle state.
As noted above, in addition, the predetermined idle state may begin based on any of the scenarios noted above. In one embodiment, the predetermined idle period of time begins when all of the shutdown conditions are met and the predetermined idle period of time is restarted if any of the shutdown conditions are violated. In another embodiment, the predetermined idle period of time begins when all of the engines of the off-highway vehicle have reached an rpm corresponding to idle and is only restarted if any of the engines are increased to a revolutions per minute above the revolutions per minute corresponding to idle such that if none of the engines of the off-highway vehicle have been at a revolutions per minute above a revolutions per minute corresponding to idle for the predetermined idle period of time and the shutdown conditions are met at the end of the predetermined idle period of time, the engines are stopped. In another embodiment, the predetermined idle period time begins when the throttle position is in a position corresponding to idle and the direction input is in neutral, and is restarted only if the revolutions per minute of the first engine increase above the revolutions per minute corresponding to idle.
Thus, one embodiment comprises an off-highway vehicle having an engine in an idle state wherein the engine produces no motive force in the idle state and wherein the engine is in the idle state. The vehicle comprises an engine 104, 106 and a controller 102 for controlling operation of the engine. The controller monitors at least one of a battery voltage of the vehicle, an ambient air temperature of the vehicle, a direction input of the vehicle, a brake cylinder pressure of the vehicle, an engine start input of the vehicle, and a battery charging current via sensors, as noted above. The controller starts the engine in response to at least one of the following start-up conditions:
the monitored engine start input is activated by an operator.
The controller stops the engine after a predetermined idle period of time in response to at least one of the following shutdown conditions:
the monitored brake cylinder pressure is above a predetermined second brake cylinder pressure.
The controller described herein for executing instructions embodying methods of the present invention may be a computer, a dedicated computing device, a network of computing devices, or any other similar device.
The order of execution or performance of the operations in embodiments of the invention illustrated and described herein is not essential, unless otherwise specified. That is, the operations may be performed in any order, unless otherwise specified, and embodiments of the invention may include additional or fewer operations than those disclosed herein. For example, it is contemplated that executing or performing a particular operation before, contemporaneously with, or after another operation is within the scope of aspects of the invention.
Embodiments of the invention may be implemented with computer-executable instructions. The computer-executable instructions may be organized into one or more computer-executable components or modules. Aspects of the invention may be implemented with any number and organization of such components or modules. For example, aspects of the invention are not limited to the specific computer-executable instructions or the specific components or modules illustrated in the figures and described herein. Other embodiments of the invention may include different computer-executable instructions or components having more or less functionality than illustrated and described herein.
When introducing elements of the present invention or the preferred embodiments(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.
Having described aspects of the invention in detail, it will be apparent that modifications and variations are possible without departing from the scope of aspects of the invention as defined in the appended claims.
As various changes could be made in the above constructions, products, and methods without departing from the scope of aspects of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.