US20130186349A1

US20130186349A1 - Reductant supply line heating system

Info

Publication number: US20130186349A1
Application number: US13/356,745
Authority: US
Inventors: Cameron J. Wright; Christopher M. Gruel
Original assignee: Caterpillar Inc
Current assignee: Caterpillar Inc
Priority date: 2012-01-24
Filing date: 2012-01-24
Publication date: 2013-07-25

Abstract

A system including a reductant tank, a receiver, a first valve, a reductant supply line, a plurality of sensors, and a controller is provided. The reductant tank is configured to store a reductant. The receiver is configured to receive a supply of the reductant from an off-board reservoir. The first valve is in communication with the reductant tank and is configured to control a reductant flow into the reductant tank. The reductant supply line is in fluid communication with the receiver and is configured to provide the reductant flow to the first valve. The plurality of sensors is configured to generate a signal. The controller is in communication with the plurality of sensors. The controller is configured to issue a command to a heating element to modulate a temperature of the reductant supply line based, at least in part, on the signal generated by the plurality of sensors.

Description

TECHNICAL FIELD

The present disclosure is relates to a heating system, and more particularly to the heating system for a reductant supply line.

BACKGROUND

Heating systems are generally known to be employed to maintain fluid viscosity of a reductant in an aftertreatment system. U.S. Published Application No. 2008/0298788 relates to a heated hose assembly including an extruded inner liner, an intermediate layer comprising strands of a nonmetallic material, and at least one heating wire. Each of the nonmetallic material and heating wires is interwoven about the exterior of the extruded inner liner. The heated hose assembly further includes an outer coating dispersed throughout the strands of the intermediate layer, and a crimp attachment component for attaching the at least one heating wire to a power source.

SUMMARY OF THE DISCLOSURE

In one aspect, the present disclosure provides a system. The system includes a reductant tank, a receiver, a first valve, a reductant supply line, a plurality of sensors, and a controller. The reductant tank is configured to store a reductant. The receiver is configured to receive a supply of the reductant from an off-board reservoir. The first valve is in communication with the reductant tank and the first valve is configured to control a reductant flow into the reductant tank. The reductant supply line is in fluid communication with the receiver. The reductant supply line is configured to provide the reductant flow to the first valve. The plurality of sensors is configured to generate a signal based on one or parameters. The controller is in communication with the plurality of sensors. The controller is configured to issue a command to a heating element to modulate a temperature of the reductant supply line based, at least in part on the signal generated by the plurality of sensors.
In another aspect, the disclosure provides a method for modulating a temperature of a reductant supply line. The method receives one or more signals from a plurality of sensors. The method determines a heating requirement of the reductant supply line based, at least in part, on the received signals from the plurality of sensors. The method issues a command to a heating element in communication with the reductant supply line to modulate the temperature of the reductant supply line based, at least in part, on the determination of the heating requirement of the reductant supply line.
Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic view of an exemplary system, according to one embodiment of the present disclosure; and

FIG. 2 is a process for modulating a temperature of a reductant supply line.

DETAILED DESCRIPTION

FIG. 1 illustrates an exemplary system 100. The system 100 may include a reductant tank 102. The reductant tank 102 stores a reductant. In one embodiment, the reductant may include, without any limitation, diesel exhaust fluid (DEF), ammonia or any other reducing agent.
The reductant tank 102 may be located in an engine compartment of a machine and the reductant tank 102 may either be a part of or connected to an aftertreatment system used in the machine. The machine may include for example, on-highway trucks or vehicles, off-highway trucks or machines, earth moving equipment, generators, aerospace applications, locomotive applications, marine applications, pumps, stationary equipment, or other engine powered applications.
In one embodiment, the reductant tank 102 may be provided in proximity to a fuel tank (not shown in figure) in the engine compartment. A person of ordinary skill in the art will appreciate that the reductant tank 102 may be located anywhere in the machine. Moreover, the reductant tank 102 may or may not be thermally insulated. The insulation, if present, may be provided by any suitable means in order to maintain the reductant at a threshold temperature. Other parameters related to the reductant tank 102 such as size, shape, location, and material used may vary within the scope of the disclosure. During operation of the aftertreatment system, a level of the reductant stored in the reductant tank 102 may reduce due to usage. Hence, the reductant tank 102 may need to be refilled with the reductant.
As shown in FIG. 1, a receiver 104 is configured to connect to receive a supply of the reductant from an off-board reservoir. The reservoir or any other storage located at the ground level may be temporarily connected to the receiver 104 in order to supply the reductant to the system 100. For example, an external nozzle of a pump connected to the reservoir is plugged into the receiver 104 to provide the supply of the reductant. In another embodiment, the receiver 104 may be located proximal to the ground level, facilitating in ease of access.
A first valve 106 is in communication with reductant tank 102. The first valve 106 may be configured to control a reductant flow into the reductant tank 102. In one embodiment, the first valve 106 may be located at a shut-off level of the reductant tank 106. The receiver 104 may be in fluid communication with the first valve 106 via a reductant supply line 108. The reductant supply line 108 may provide the reductant flow to the first valve 106. The system 100 may include any other necessary components needed to fill, vent and/or stop the refill of the reductant tank 102. Moreover, the reductant supply line 108 may be hose or pipe made of any suitable material, such as plastic, rubber, and the like. Parameters such as length, diameter and flexibility of the reductant supply line 108 may vary. In one embodiment, a part or entire of the reductant supply line 108 may be located outside of the machine.
In one embodiment, a portion of the reductant flow may be frozen in the reductant supply line 108. As shown in FIG. 1, the system 100 may include a controller 110 in a communication with a plurality of sensors 112. The plurality of sensors 112 may generate signals based on one or parameters. The controller 110 may modulate a temperature of the reductant supply line 108 based on the signals generated by the plurality of sensors 112.
In one embodiment, the plurality of sensors 112 may include a temperature sensor 114, a reductant level sensor 116, a fuel level sensor 118 and/or an engine sensor 120, which are connected to the controller 110 via communication lines respectively 122, 124, 126, 128 respectively. The one or more parameters may include a temperature of ambient air, a reductant level, a fuel level, an engine state, and the like.
The temperature sensor 114 may generate a signal indicative of the temperature of the ambient air. The reductant level sensor 116 provides a reading of the level of the reductant in the reductant tank 102. The fuel level sensor 118 provides a reading of the level of fuel in the fuel tank. The engine sensor 120 may generate a signal indicative of the engine state. For example, the engine may be in an active state, idle state or shutdown state. A person of ordinary skill in the art will appreciate that the location of the plurality of sensors 112 does not limit the scope of the disclosure. Moreover, the plurality of sensors 112 may include other sensors not mentioned above.
As shown in FIG. 1, a heating element 130 may be in communication with the controller 110 via communication line 132. The heating element 130 may be coupled to the reductant supply line 108 via communication line 134. In one embodiment, the heating element 130 may be integrated with the reductant supply line 108, for example, like electrically heated lines. The heating element 130 may include any suitable electrical heater, without any limitation.
In one embodiment, the controller 110 may be a microcomputer including a microprocessor unit, input and output ports, an electronic storage medium for executable programs and calibration values, random access memory, a data bus, and the like. The controller 110 may also include a routine for controlling and/or diagnosing one or more components of the system 100. Additionally, in another embodiment, the controller 110 may be located at a remote, on-board location. In yet another embodiment, the controller 110 may be located within the engine compartment of the machine.
The operation of the controller 110 to modulate the temperature of the reductant supply line 108 will be explained in detail with connection to FIG. 2.

INDUSTRIAL APPLICABILITY

The above described disclosure relates to the system 100 of refilling the reductant tank 102. During the reductant refilling operation of the reductant tank 102, a part of the reductant may be stranded in the reductant supply line 108. The disclosure is directed towards heating the reductant supply line 108 to clear the stranded reductant present in the reductant supply line 108. In one embodiment, the reductant may be DEF. In extremely cold conditions, the DEF may have a tendency to freeze in the reductant supply line 108. The freezing point for the DEF containing 32.5% by weight of urea is −11° C.
A general tendency by way of convenience would be to refill the reductant tank 102 when the fuel tank is being filled. If the heating of the reductant supply line 108 was based only on the level of the reductant in the reductant tank 102, then on some instances when the fuel tank needed refilling but the reductant tank 102 did not, the reductant supply line 108 would still be frozen. Thus, the disclosure takes into consideration inputs received from the plurality of sensors 112, not limited to any one of them.
The disclosure also addresses loss of productive time due to manual intervention wherein if the heating of the reductant supply line 108 was triggered manually, an operator would have to wait for certain duration of time until the operator could begin to refill the reductant tank 102. The disclosure also relates to cut off of the heat supplied to the reductant supply line 108 since a constantly running heating element may result in loss of efficiency, and undue wear on components in the machine.
Initially, at step 202, the controller 110 may receive one or more signals from the plurality of sensors 112. In one embodiment, the plurality of sensors 112 may include the temperature sensor 114. The signal received from the temperature sensor 114 may be indicative of the ambient temperature. In another embodiment, the plurality of sensors 112 may include the reductant level sensor 116 and/or the fuel level sensor 118. The signals received from the reductant level sensor 116 and/or the fuel level sensor 118 may be indicative of the fill level of the reductant and/or the fuel respectively. In yet another embodiment, the plurality of sensors 112 may include the engine sensor 120.
Subsequently, at step 204, a heating requirement of the reductant supply line 108 may be determined. When the controller 110 receives the signal from the temperature sensor 114, the controller 110 may compare the temperature of the ambient air provided by the temperature sensor 114, with a pre-determined threshold temperature of the reductant supply line 108. In a situation where the ambient temperature is below or less than the pre-determined threshold temperature, the controller 110 may determine that the reductant supply line 108 requires heating. For example, when the ambient temperature falls below −11° C., the controller 110 may determine that the reductant supply line 108 containing the DEF requires heating.
Additionally, the reductant supply line 108 may require heating prior to refilling of the reductant tank 102, in order to clear the reductant supply line 108 of the reductant that may be stranded and frozen in the reductant supply line 108. Hence, based on the signal received from the reductant fill sensor 116, the controller 110 may estimate when a next or a subsequent filling of the reductant tank may occur. Accordingly, the controller 110 may determine that the reductant supply line 108 requires heating prior to the subsequent refill of the reductant tank 102.
Moreover, in some situations, the refill of the reductant tank 102 may be further based on the refill requirement of the fuel tank. Generally, for the purpose of convenience, the reductant tank 102 may be filled each time the machine requires a fuel refill. Hence, in this situation, the heating requirement of the reductant supply line 108 may be based on a refill requirement of the fuel tank. In one embodiment, the controller 110 may estimate a next or subsequent filling of the fuel tank. Based on the signal received from the fuel level sensor 118, the controller may determine the heating requirement of the reductant supply line 108 prior to the refilling of the fuel tank. Additionally, in some situations, the consumption of the fuel by the machine may be more than the usage of reductant. Hence, in one embodiment the controller 110 may maintain a relation between the refill cycles of the fuel tank and the reductant tank 102 and accordingly determine the heating requirement of the reductant supply line 108 based on the estimated next reductant tank 102 refill requirement.
In one embodiment, based on the signal received from the engine sensor 120, the controller 110 may determine the engine state of the machine, for example, active state, idle state or shutdown state. In an exemplary situation, the controller 110 may determine that the reductant supply line 108 requires heating, when the engine is determined to be in the shutdown state for a long time.
In another embodiment, the controller 110 may receive signals from any combination of the above described plurality of sensors 112. In this case, the controller 110 may assign priorities in the form of weighting factors to each of the received signals. The controller 110 may then determine the heating requirement of the reductant supply line 108 based on the prioritized signals. A person of ordinary skill in the art will appreciate that the situations described above are merely on exemplary basis and do not limit the scope of the disclosure. The controller 110 may determine the heating requirement of the reductant supply line 108 based on other factors, without any limitation.
At step 206, based on the determined heating requirement, a command is issued to the heating element 130 to increase the temperature of the reductant supply line 108. Hence, the command issued by the controller 110 may be used to initiate the heating of the reductant supply line 108. As described above, in one embodiment, the heating element 130 may be integrated with the reductant supply line 108. A person of ordinary skill in the art will appreciate that the use of electrically heated lines is known in art and may considerably reduce the cost associated with the setup of the system 100. Moreover, the simple connection of the reductant supply line 108 to the machine facilitates in providing simple user purchased equipment.
Moreover, the DEF should not be heated excessively, as high temperatures may result in breakdown of the chemical properties of the DEF. Also, excessive or unrequired heating of the reductant supply line 108 may result in unnecessary loss of energy. In one embodiment, the controller 110 may also issue a command to stop an ongoing heating of the reductant supply line 108. In one embodiment, the heating of the reductant supply line 108 have a time based control such that the heating may automatically cease after a pre-defined interval of time.
In one embodiment, another temperature sensor may be coupled with the reductant supply line 108 to generate signals indicative of the temperature of the reductant supply line 108. The controller 110 may compare the temperature of the reductant supply line 108 with the pre-determined threshold temperature, either periodically or during an ongoing heating of the reductant supply line 108. Hence, the controller 110 may keep a check to prevent excessive heating of the reductant supply line 108.
In yet another embodiment, the controller 110 may also control or regulate the magnitude of heat supplied to the reductant supply line 108 by the heating element 130. In an exemplary implementation, the magnitude of heat supplied to the reductant supply line 108 may be varied by modulating a pulse width modulated (PWM) signal where the duty cycle of the PWM signal is directly proportional to the level of heat supplied by the heating element 130 to the reductant supply line 108.
Moreover, in other situations, the controller 110 may be manually triggered to issue the command to the heating element 130 via any suitable user interface. Additionally, provisions may be made to drain off the stranded reductant present in the reductant supply line 108. An exemplary provision may include and external line having a manual valve, such that the external line is connected to the reductant supply line 108.
While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.

Claims

What is claimed is:

1. A system comprising:

a reductant tank configured to store a reductant;

a receiver configured to receive a supply of the reductant from an off-board reservoir;

a first valve in communication with the reductant tank configured to control a reductant flow into the reductant tank;

a reductant supply line in fluid communication with the receiver, the reductant supply line configured to provide the reductant flow to the first valve;

a plurality of sensors configured to generate a signal based on one or parameters; and

a controller in communication with the plurality of sensors, the controller configured to issue a command to a heating element to modulate a temperature of the reductant supply line based, at least in part on the signal generated by the plurality of sensors.

2. The system of claim 1, wherein the reductant includes a diesel emission fuel.

3. The system of claim 1, wherein the plurality of sensors includes at least one of a temperature sensor, a reductant level sensor, a fuel level sensor and an engine sensor.

4. The system of claim 1, wherein the one or more parameters include at least one of a temperature of ambient air, a reductant level, a fuel level and an engine state.

5. The system of claim 1, wherein the heating element is in communication with the controller, the heating element configured to increase the temperature of the reductant supply line.

6. The system of claim 5, wherein the heating element is integrated with the reductant supply line.

7. The system of claim 5, wherein the temperature of the reductant supply line is increased for a pre-determined period of time.

8. The system of claim 1, wherein the controller is at a remote location.

9. A method comprising:

receiving one or more signals from a plurality of sensors;

determining a heating requirement of a reductant supply line based, at least in part, on the received signals from the plurality of sensors; and

issuing a command to a heating element in communication with the reductant supply line to modulate a temperature of the reductant supply line based, at least in part, on the determination of the heating requirement of the reductant supply line.

10. The method of claim 9, wherein determining a heating requirement of a reductant supply line further includes estimating a refill requirement of a reductant tank based on the signal received from a reductant level sensor, wherein the reductant supply line is heated prior to the reductant tank refill.

11. The method of claim 9, wherein determining a heating requirement of a reductant supply line further includes estimating a refill requirement of a fuel tank based on the signal received from a fuel level sensor, wherein the reductant supply line is heated prior to the fuel tank refill.

12. The method of claim 9, wherein determining a heating requirement of a reductant supply line further includes determining an engine state based on the signal received from an engine sensor, wherein the reductant supply line is heated based on the engine state.

13. The method of claim 9, wherein determining a heating requirement of a reductant supply line further includes comparing a temperature of ambient air provided by a temperature sensor with a predetermined threshold temperature of the reductant supply line.

14. The method of claim 9 further including providing a time based control for modulating the temperature of the reductant supply line.

15. A computer based system for modulating a temperature associated with a reductant supply line comprising:

a communication interface communicating with a memory;

the memory configured to communicate with a processor; and

the processor, in response to executing a computer program, performs operations comprising:

receiving one or more signals from a plurality of sensors;

determining a heating requirement of the reductant supply line based, at least in part, on the received signals from the plurality of sensors; and

issuing a command to a heating element in communication with the reductant supply line based, at least in part, on the determination of the heating requirement of the reductant supply line.

16. The computer based system of claim 15, wherein determining a heating requirement of a reductant supply line further includes estimating a refill requirement of a reductant tank based on the signal received from a reductant level sensor, wherein the reductant supply line is heated prior to the reductant tank refill.

17. The computer based system of claim 15, wherein determining a heating requirement of a reductant supply line further includes estimating a refill requirement of a fuel tank based on the signal received from a fuel level sensor, wherein the reductant supply line is heated prior to the fuel tank refill.

18. The computer based system of claim 15, wherein determining a heating requirement of a reductant supply line further includes determining an engine state based on the signal received from an engine sensor, wherein the reductant supply line is heated based on the engine state.

19. The computer based system of claim 15, wherein determining a heating requirement of a reductant supply line further includes comparing a temperature of ambient air provided by a temperature sensor with a predetermined threshold temperature of the reductant supply line.

20. The computer based system of claim 15 further including providing a time based control for modulating the temperature of the reductant supply line.