Patent Application
20140102483
The present disclosure relates generally to debris removal systems. Specifically, an embodiment of the present invention relates to a debris removal system for removing debris from a chamber.
Some components of machines can be damaged if dust or debris come in contact with or enter the component. For example, if dust enters an intake manifold of an engine, it may damage the combustion cylinders. Often machines working in dusty, or debris filled environments are equipped with air filtration systems. The air filtration systems protect sensitive components by removing dust and/or debris from air entering or having contact with the components.
Some filtration systems trap larger debris in a debris chamber and then filter the remaining air. The chamber may be fluidly connected with an air outlet through an exhaust pipe which may draw the debris out of the chamber and expel it through the air outlet into the air surrounding the machine. U.S. Pat. No. 7,004,987 issued to Pikesh et al., discloses a pre-cleaner for an air induction system of an internal combustion engine including a housing enclosing an upper chamber and an aspirator port chamber. The upper chamber contains a plurality of particulate separator tubes arranged in a predetermined array. Each of the tubes includes a particulate outlet through which particles removed from air flowing through the tube en route to the engine are discharged. The aspirator port chamber is located beneath, and is upwardly open to, the particulate outlets and includes an upwardly facing particle collecting surface located directly beneath the particulate outlets. Particles can fall from the tubes into the aspirator port chamber and onto the upwardly facing particle collecting surface. The housing includes a generally horizontally facing aspirator port in the aspirator port chamber adjacent to and facing the particle collecting surface. The housing also includes an element disposed for connecting the aspirator port to an exhaust tract of the internal combustion engine such that the exhaust flow through the exhaust tract will generate a suction condition in the aspirator port when the engine is operated. The particle collecting surface is positioned and oriented such that the suction generated by the exhaust flow during the operation of the engine will draw a flow of air from the upper chamber across the particle collecting surface such that particles collected on the surface will be drawn in an at least generally horizontal direction into the aspirator port.
In some operating conditions, airflow created through a pre-cleaner by a flow of gas through an exhaust pipe and an air outlet, to draw debris out of a debris chamber, through a debris conduit, and through the air outlet may not be sufficient to remove enough debris from the chamber.
Disclosed is a system to remove debris from a chamber including a debris chamber, an exhaust pipe, a debris conduit, an air outlet, and a tab. The exhaust pipe directs a flow of gas into the air outlet and includes an exhaust pipe interior. The debris conduit connects the chamber with at least one of the exhaust pipe interior and the air outlet and includes a debris conduit end disposed in at least one of the exhaust pipe interior and the air outlet. The tab has at least three outer edges forming at least two outer corners, and an adjacent edge, the adjacent edge adjacent to the debris conduit end.
In another aspect, disclosed is a machine including a body, an air filtration system, an exhaust pipe, an engine, a debris conduit, and a tab. The body defines a compartment with an air inlet and an air outlet. The air filtration system includes a pre-cleaner with a debris collection area disposed, the pre-cleaner configured to filter and trap debris in the debris collection area. The air filtration system is disposed in the air inlet. An air outlet stack is disposed in the air outlet. The exhaust pipe directs exhaust gas into and out of the air outlet, and includes an interior and an exhaust pipe end having a venturi portion. The engine is disposed in the compartment and is configured to exhaust gases through the exhaust pipe. The engine includes an intake manifold fluidly connected to the air inlet through the air filtration system. The debris conduit connects the debris collection area with at least one of the interior of the exhaust pipe and the air outlet, and includes a debris conduit end. The debris conduit end is disposed in at least one of the interior of the exhaust pipe and the air outlet. The debris conduit is configured for directing debris from the debris chamber through and out of at least one of the exhaust pipe and the air outlet. The tab, with at least three outer edges forming at least two outer corners and an adjacent edge, is adjacent to the debris conduit end.
In another aspect disclosed is a method for removing debris from a debris chamber. The method includes directing a first gas through an exhaust pipe; over an outer surface, and around at least three outer edges, and two corners formed by the at least three outer edges of a tab; and through an air outlet. The method further includes flowing a second gas through the debris chamber and a debris conduit; and over an inner surface, and around the at least three outer edges, and two corners formed by the three outer edges of the tab. Additionally, the method includes creating vortex flow between the first gas and the second gas, and drawing debris out of the debris chamber, through the debris conduit, and through the air outlet.
Reference will now be made in detail to specific embodiments or features, examples of which are illustrated in the accompanying drawings. Generally, corresponding or similar reference numbers will be used, when possible, throughout the drawings to refer to the same or corresponding parts. Elements in schematics, included in the drawings, and described herein, may not be drawn with dimensions or in relation to other elements to any realistic scale. But, may rather be drawn to illustrate different aspects of the disclosure.
Referring now to
The wheel loader 104 includes a body 106 which defines a compartment 108 including an air outlet 110, and an air inlet 114. The air outlet includes an air outlet stack 112. The air inlet 114 includes an air filtration system 116, with a debris chamber 133 (shown in relation to
The wheel loader 104 includes a power source 117. In the illustrated embodiment, the power source 117 includes an engine 118 disposed in the compartment 108. The engine 118 may include an internal combustion engine. The wheel loader 104 is equipped with systems that facilitate the operation of the wheel loader 104 at a worksite 126. In the illustrated embodiment, these systems include a work implement system 124, and a drive system 120, both of which are powered by the engine 118. The drive system 120 propels the wheel loader 104 on ground engaging devices 122 (depicted as wheels) to move the wheel loader 104 from one location to another. The work implement system 124 includes a bucket 128 and actuators and linkages 130 to move the bucket 128 to perform work at the worksite 126. Wheel loader 104 includes an embodiment of a debris removal system 132, depicted in
Referring now to
In the illustrated embodiment, the system 132 includes a housing 148 which defines the compartment 108, the air outlet 110, and an air inlet 114. The debris chamber 133, debris conduit 142, and at least a portion of the exhaust pipe 136 may be substantially enclosed by the housing 148. The debris chamber 133 may include any substantially enclosed space or cavity for collecting dust and/or debris. The debris may include tiny pieces of rock, mud, seeds, chaff, ash, or other substances which may become airborne. In the illustrated embodiment, the debris chamber 133 includes a debris collection area 134 which is contained in, and is an element of, the precleaner 119. A flow of a second gas is illustrated in
In the embodiment illustrated, the engine 118 includes an air intake manifold 150 fluidly connecting the engine 118 to the outside of the compartment 108 through the air filtration system 116. A portion of the second gas flowing through the air inlet 114 may flow through the pre-cleaner 119 and the air filter 121 and into the intake manifold 150. The pre-cleaner 119 may remove larger pieces of debris from the second gas by trapping them in the collection area 134, and then remove additional dust and smaller debris particles through the air filter 121, before the second gas is allowed to flow into the intake manifold 150. Another portion of the second gas flowing through the inlet 114 may flow through the collection area 134 of the pre-cleaner 119 and then into the debris conduit 142.
The flow of the first gas from the exhaust pipe 136 may include a flow of heated gas, for example, a flow of heated exhaust gas from the engine 118. In the illustrated embodiment, the exhaust pipe 136 fluidly connects the engine 118, with the air outlet 110 to expel exhaust gas. The exhaust gas from the engine 118 may flow through one or more aftertreatment devices 154, and through one or more sound suppression devices 156, before flowing into the exhaust pipe 136 and then through the air outlet 110. Although engine 118 is depicted disposed in the compartment 108, in other embodiments, engine 118 may be located outside or only partially disposed in the compartment 108. Although engine 118 exhausts the flow of the first gas in the illustrated embodiment, in other embodiments the flow of the first gas may originate and be directed through the exhaust pipe 136 by other devices or processes known in the art. For example, a turbine may exhaust the flow of the first gas into the exhaust pipe 136, or a manufacturing process may create heat and a series of fans, air conduits, and/or valves may direct the flow of the first gas through the exhaust pipe 136.
In the depicted embodiment, the exhaust pipe 136 includes an exhaust pipe end 138 including a venturi portion 140. The venturi portion 140 includes a neck portion 141 providing a restriction such that the velocity of the flow of the first gas is increased upon exiting the neck portion 141, as is known in the art.
In the depicted embodiment, the debris conduit 142 connects the debris chamber 133 to the exhaust pipe interior 137. In one embodiment, a portion of the debris conduit 142 including the debris conduit end 144 may be inserted into the exhaust pipe interior 137 through an aperture in the wall of the exhaust pipe 136. In other embodiments the debris conduit 142 or a portion of the debris conduit 142, and the exhaust pipe 136 or a portion of the exhaust pipe 136 may be manufactured as a single component. The debris conduit 142 and the debris conduit end 144 are positioned in relation to the exhaust pipe 136, such that debris from the debris chamber 133 is directed into at least one of the exhaust pipe 136 and the air outlet 110. In the depicted embodiment, the air outlet 110 includes the air outlet stack 112. The exhaust pipe end 138 and debris conduit end 144 are positioned in the air outlet stack 112 such that the flow of the first gas from the exhaust pipe 136 into the air outlet stack 112 creates a low pressure area proximate the debris conduit end 144. In the depicted embodiment, the low pressure area may be created above the debris conduit end 144. The second gas from outside the compartment 108, entering the compartment 108 through the air filtration system 116, may be at a higher pressure than the low pressure area created proximate the debris conduit end 144. The second gas may flow from the higher pressure area outside the compartment, through the collection area 134, and through the debris conduit 142. The second gas may carry dust and/or debris from the collection area 134, through the debris conduit 142, through the outlet stack 112, and out of the compartment 108.
In the embodiment illustrated, the housing 148 defines an aperture 158 fluidly connecting the compartment 108 with air outside the housing 148. A flow of a third gas is illustrated in
Referring now to
In the illustrated embodiment, the debris conduit 142 includes an exterior wall 164 and an interior wall 174. In the illustrated embodiment, debris conduit 142 is substantially cylindrical. In alternative embodiments, the debris conduit 142 may be any elongated tube type shape known in the art to be operable to fluidly connect the debris chamber 133 with one of the interior of the exhaust stack 136 and the air outlet 110. Non-limiting examples include a tube like structure with cross sections in the shapes of ellipses or polygons such as octagons, or rectangles. In some embodiments, the debris conduit 142 may include cross sections which differ in shape and size at different points. The debris conduit 142 may, for example, include a venturi type shape.
Multiple tabs 146 are attached to, and spaced around the debris conduit end 144. In the illustrated embodiment, the tabs 146 are angled out from the exterior wall 164 and circumferentially spaced around the circular debris conduit end 142. Each tab 146 includes an adjacent edge 162 adjacent the debris conduit end 144, and at least three outer edges 160 angled out from the exterior wall 164 of the debris conduit 142. The outer edges 160 form at least two corners 161.
In the illustrated embodiment four tabs 146 are circumferentially evenly spaced around the debris conduit end 144. In alternative embodiments, different numbers of tabs 146 may be evenly, or unevenly, spaced around the debris conduit end 144. There may be, for example, as few as one tab 146, or as many as eight tabs 146. The number of tabs 146, the shape of tabs 146, the size of tabs 146, and the orientation of the tabs in relation to the debris conduit 142 may be determined as a function of a number of factors. Non-limiting examples of factors to be considered include estimates of the range of velocities and temperatures, the velocity profile, and the range of other characteristics of the flow of the first gas. Other examples may include the geometry of the debris conduit 142, the debris conduit end 144, the debris chamber 133, the air inlet 114, and the filter 116; the possible characteristics of the second gas; and the size and configuration of the air outlet stack 112.
The tabs 146 include an inner surface 176 and an outer surface 178. The tabs may be held stationery such that the first gas flows over the outer surface 178 and around the outer edges 160 and corners 162; and the second gas flows over the inner surface 176 and around the outer edges 160 and corners 162; in any manner known in the art.
In the illustrated embodiment, the tabs 146 are fixedly attached to the debris conduit end 144 such that the adjacent edge 162 is adjacent the debris conduit end 144. The tabs 146 may, for example, be welded onto the exterior wall 164 or interior wall 174 of the debris conduit 142 with attachment portions 168 as shown and explained in relation to
In the illustrated embodiment, each tab 146 is substantially flat. The adjacent edge 162 and outer edges 160 form the outline of the inner surface 176 and the outer surface 178. Both the inner surface 176 and the outer surface 178 are generally planar. In alternative embodiments, the tabs 146 may be curved as opposed to flat.
In the embodiment illustrated, each tab 146 is a generally a trapezoidal shape with a semi-circular adjacent edge 162, and three outer edges 160. As depicted in
In the embodiment illustrated, each tab 146 is generally the same size and shape, and adjacent the debris conduit end 144 at the same conduit-tab angle (α). In alternative embodiments, the tabs 146 may be different shapes and sizes, and adjacent the debris conduit end 144 at different conduit-tab angles (α).
Referring now to
In one embodiment of the tab assembly 166, 266; the tab 146 and the tab attachment piece 268 may be formed as one integral piece through molding or from bending and shaping sheet metal. In other embodiments, the tab 146 and the tab attachment piece 168, 268 may be welded together, riveted together, bolted together or fixedly attached together by any means known in the art.
Air filtration systems to remove debris and dust from air entering or having contact with components of a machine may include a debris chamber to trap larger pieces of debris. The debris chamber may be fluidly connected, through a debris conduit, to a flow of gas from an exhaust pipe, to create a low pressure area and a flow of air through the debris conduit from a higher pressure area, to draw the debris out of the chamber, and expel it outside the machine. In some operating conditions, the flow created may not be sufficient to remove enough debris from the chamber. Tabs at the end of the debris conduit may create vortex flow between the gas being drawn through the debris conduit and the gas flowing from the exhaust pipe. This vortex flow may enhance the mixing of the two gases and increase the velocity of the gas flowing through the debris conduit, and increase the amount of debris removed from the chamber. Experimentation, modeling, and simulation have indicated that the tab can increase the vortex flow and thus the amount of debris removed from the debris chamber.
Referring now to
The method 200 starts at step 202 and proceeds to step 204. In step 204, the flow of the first gas is directed through the exhaust pipe 136. In the embodiment depicted in
In step 206, the flow of the first gas is directed over the outer surface 178 of a tab 146, and over at least three outer edges 160 and two corners 161 formed by the outer edges 160 of the tab 146. In the embodiment depicted in
In step 208, the first gas is directed through the air outlet 110. In the embodiment depicted in
In step 210, the flow of the second gas flows through the debris conduit 142. In the embodiment depicted in
In step 212, the flow of the second gas passes over the inner surface 176 of the multiple tabs 146, and over and around the outer edges 160 and corners 161. In the embodiment depicted in
In step 214, vortex flow 184 is created between the first gas and the second gas. Referring now to
In step 216, debris is drawn through the debris conduit 142 and expelled out the air outlet 110. When heated exhaust gas is directed through the exhaust pipe and in a flow path direction out the air outlet stack 112, flow of air from outside the compartment 108 may be created through the collection area 134 and debris conduit 142. This flow may be strong enough to draw debris from the collection area 134, through the debris conduit 142, and out the air outlet stack 112. However, this flow may not be strong enough to draw all debris out of the collection area 134. Creating vortex flow as the first gas and the second gas meet at the corners 161 of the tabs 146 increases the mixing of the first gas and the second gas and thus the velocity of the second gas. Increasing the velocity of the second gas may increase the amount of debris drawn out of the debris chamber 133. The method 200 proceeds to step 218 and ends.
It will be appreciated that the foregoing description provides examples of the disclosed system and technique. However, it is contemplated that other implementations of the disclosure may differ in detail from the foregoing examples. All references to the disclosure or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the disclosure entirely unless otherwise indicated.
