System for self-aligning exhaust gas sensor connectors

Abstract

Systems and methods for self-aligning exhaust gas sensor fittings are provided. In one example, the system may include: a tapered tube having a flange at its wider end; a nut having a head, an externally threaded bottom, and a tapered inner cavity adapted to fit around the tapered tube; and a boss having a threaded inner cavity adapted to engage with the threaded bottom of the nut and having an engagement cavity for receiving the flange. A seal may be formed between the tapered tube and the boss by inserting the flange into the engagement cavity, mating the externally threaded bottom of the nut with the threaded inner cavity of the boss, and twisting the nut until the bottom surface of the externally threaded bottom pushes against the flange.

Description

Technical Field

[0001] The present description generally relates to systems and methods for exhaust pressure sensors in vehicles. Background Art

[0002] The attachment of some sensors (such as exhaust pressure sensors) to the vehicle requires precise orientation of the pipe (or tube) assembly in order to align the sensor with a fixed base (e.g., a boss) welded to the exhaust passage. Typically, the pipe assembly includes a pressure washer having a protrusion that matches a recess (e.g., a groove) in the fixed base so that the pressure washer is assembled into the fixed base in a single orientation. This alignment constraint increases the complexity of the sensor installation process. If the joint (joint) created between the pipe assembly and the fixed base is misaligned, the stress on the pipe assembly may increase, causing sensor degradation. In one example, if the pipe assembly is not aligned with other sensor components, the pipe can be twisted to force alignment, thereby straining the sensor joint. As another example, misalignment may press the exhaust sensor into other vehicle components, thereby straining the pipe assembly and the sensor joint, which may cause the sensor to degrade over time. Therefore, in order to correct the misalignment, the fixed base can be removed, realigned, and re-welded, which increases the time and cost of sensor installation. Summary of the invention

[0003] The inventors herein have recognized that by eliminating the opportunity for misalignment, the time and cost of sensor installation can be reduced. In one example, the above problem can be solved by a system comprising: a tapered tube having a flange at its wider end; a nut assembly having a head, a cylindrical externally threaded bottom extending downwardly from the head, and a tapered inner cavity adapted to be positioned above the tapered tube; and a boss having a threaded inner cavity adapted to engage with the threaded bottom of the nut assembly, and an engagement cavity extending below the threaded inner cavity adapted to receive the flange. In this way, exhaust gas sensor joint alignment constraints can be reduced.

[0004] As an example, the nut assembly can be positioned around the tapered tube, and the tapered tube and the nut assembly can rotate freely around the common center axis. When the flange of the tapered tube is inserted into the engagement cavity of the boss, the tapered tube and the boss can form a seal, the threaded bottom of the nut assembly cooperates with the threaded inner cavity of the boss, and the bottommost end of the threaded bottom presses the flange into the engagement cavity. Once the flange is pressed into the engagement cavity of the boss, further rotation of the tapered tube can be prevented, wherein the tapered tube is firmly held in place by the downward force from the nut assembly. In this way, the tapered tube can be inserted into the boss in any rotational orientation (relative to the common center axis) and adjusted to align with other vehicle components until the nut assembly is twisted and pushed against the flange of the tapered tube, thereby eliminating the re-welding of the boss due to misalignment of the joint. Therefore, the time and cost of exhaust gas sensor installation can be reduced. Furthermore, due to the tapering of the tube and the tapered lumen of the nut, the tapered lumen of the nut may not contact the outer wall of the tube during the torqueing process, thereby reducing stress placed on the tube during sensor installation and thereby reducing sensor degradation.

[0005] It should be understood that the above summary is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. This is not meant to establish key or essential features of the claimed subject matter, the scope of which is solely defined by the appended claims. In addition, the claimed subject matter is not limited to implementations that address any disadvantages noted above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 A schematic diagram of a vehicle system is shown.

[0007] FIG. 2 shows a side view of a tapered tube that may be included in an exhaust gas sensor fitting.

[0008] 3 illustrates a side view of an internally tapered, externally threaded nut assembly that may be included in an exhaust gas sensor fitting.

[0009] FIG. 4 depicts an angled top view of an internally threaded boss that may be included in an exhaust gas sensor fitting.

[0010] Figure 5 A first side view of the nut assembly is shown arranged around a tapered tube prior to engagement with a boss.

[0011] Figure 6 A second side view of the nut assembly is shown arranged around the tapered tube prior to engagement with the boss.

[0012] Figure 7 Shown is a side view of a tapered tube and nut assembly engaged with a boss to form an exhaust gas sensor fitting.

[0013] Figure 8 A cross-sectional side view of a tapered tube and nut assembly engaging a boss to form an exhaust gas sensor fitting is shown.

[0014] Fig. 9 An exhaust gas sensor connection is shown coupled to an exhaust passage of an exhaust system.

[0015] Fig.10 A flow chart is shown of an example method for measuring exhaust pressure using an exhaust pressure sensor coupled to an exhaust passage via an exhaust sensor connection.

[0016] Figure 2- Fig. 9 Shown approximately to scale, but other relevant dimensions may be used. DETAILED DESCRIPTION

[0017] The following description relates to systems and methods for an exhaust gas sensor connector that can be used to couple one or more sensors to a vehicle system such as a Figure 1 2 ); a nut assembly having a slightly conical inner cavity (e.g., an axial hole) and a cylindrical outer threaded bottom, such as the example nut shown in FIG. 3 ; and a cylindrical boss having a threaded inner cavity, such as the example boss shown in FIG. 4 . Specifically, the nut can be arranged around the conical tube, such as Figure 5 and Figure 6 As shown, the nut can rotate freely and slide vertically on the tapered tube and the tapered tube can rotate freely in the nut assembly. The tapered tube can be inserted into the threaded inner cavity of the boss, and the outer thread bottom of the nut assembly can cooperate with the threaded inner cavity of the boss to form an exhaust gas sensor joint, such as Figure 7 and Figure 8 The exhaust gas sensor connector can be used to install the exhaust gas pressure sensor in the exhaust system, for example Fig. 9 It is important to note that the exhaust gas sensor connector does not restrict the alignment of the exhaust gas pressure sensor during installation. Fig.10 An example method for measuring exhaust pressure via an exhaust pressure sensor mounted via an exhaust sensor connector is provided.

[0018] Figure 1A schematic diagram of a vehicle system 108 including an engine system 106 is shown. In one example, the vehicle system 108 can be propelled by combustion of a fuel / air mixture within cylinders 130 of an engine 100 of the engine system 106. In other examples, the vehicle system 108 can be a hybrid vehicle system that can obtain propulsion power from the engine system 106 and / or an onboard energy storage device, such as a battery system (not shown). An energy conversion device, such as a generator (not shown), can be operated to absorb energy from vehicle motion and / or engine operation, and then convert the absorbed energy into an energy form suitable for storage by the energy storage device.

[0019] The engine 100 of the engine system 106 is configured to combust fuel received from the fuel system 8 and air within the cylinder 130. The fuel from the fuel system 8 may be injected into the cylinder 130 via a fuel injector 166. Although only one fuel injector 166 is shown, it should be understood that each cylinder 130 may include a fuel injector 166 coupled thereto. In this manner, the fuel injector 166 provides so-called direct injection (hereinafter also referred to as "DI") of fuel into the cylinder 130. However, in other examples, the fuel injector 166 may be configured as a port fuel injector (hereinafter also referred to as "PFI") for injecting fuel upstream of the cylinder 130 (e.g., injecting fuel into the intake port). In still other examples, fuel may be delivered from the fuel system 8 to the cylinder 130 via both DI and PFI.

[0020] Fuel system 8 may include one or more fuel tanks, fuel pumps and fuel rails. For example, the fuel tank of fuel system 8 may store one or more liquid fuels, including, but not limited to, gasoline, diesel and alcohol fuels. In some examples, fuel may be stored on the vehicle as a blend of two or more different fuels. For example, the fuel tank of fuel system 8 may be configured to store a blend of gasoline and ethanol (such as E10, E85, etc.) or a blend of gasoline and methanol (such as M10, M85, etc.), whereby these fuels or fuel blends may be delivered to engine 100 via fuel injector 166. The air / fuel mixture in cylinder 130 may be ignited by compression or by spark ignition of a spark plug (not shown) coupled to each cylinder 130.

[0021] The engine system 106 includes an engine intake 123 (which may be referred to herein as an intake system) and an engine exhaust 125 (which may be referred to herein as an exhaust system). The engine intake 123 includes a throttle 162 fluidly coupled to an intake manifold 144 via an intake passage 142. Air may flow into the intake passage 142, and particulate matter (e.g., dust, dirt, etc.) may be removed from the air via an air filter 152. The amount of air entering the intake manifold 144 may be varied by varying a position of the throttle 162.

[0022] The engine exhaust 125 includes an exhaust manifold 148 leading to an exhaust passage 135, which directs the exhaust to the atmosphere. The engine exhaust 125 may also include one or more emission control devices 170, which are mounted in a close-coupled position and are configured to receive the exhaust flowing through the exhaust passage 135. The emission control device 170 may include one or more emission control devices, such as a three-way catalyst in various sequences and / or combinations, a lean NOx trap, a particulate filter (e.g., a diesel particulate filter or a gasoline particulate filter), an oxidation catalyst, etc. The exhaust may flow through the emission control device 170 before being discharged to the atmosphere.

[0023] The vehicle system 108 also includes a control system 14, which includes a controller 12. The control system 14 receives information (e.g., electrical signals) from a plurality of sensors 16 (various examples of which are described herein) and sends control signals to a plurality of actuators 81 (various examples of which are also described herein). As an example, the sensors 16 may include an exhaust gas sensor 126 located upstream of an emission control device, an exhaust gas temperature sensor 128, a manifold absolute pressure (MAP) sensor 118 coupled to an intake manifold 144, and an exhaust pressure sensor 131 coupled to an exhaust passage 135. The exhaust pressure sensor 131 may be coupled to the exhaust passage 135 via an exhaust sensor connector. Specifically, the exhaust sensor connector may be self-aligned via an unconstrained mounting, as described with respect to FIG. Figure 5-Figure 8 Further described. Other sensors (such as additional pressure sensors, temperature sensors, air-fuel ratio sensors, and composition sensors) may be coupled to various locations in the vehicle system 108. As another example, the actuators may include a fuel injector 166, a throttle 162, etc. The controller 12 receives signals from the various sensors 16 and employs various actuators 81 to adjust engine operation based on the received signals and instructions stored on the memory of the controller. For example, the controller 12 may receive an indication of exhaust pressure downstream of the emission control device 170 via the exhaust pressure sensor 131.

[0024] The controller 12 may be configured as a microcomputer including a microprocessor unit, input / output ports, read-only memory, random access memory, fail-safe memory, a controller area network (CAN) bus, etc. In some examples, the controller 12 may be configured as a powertrain control module (PCM). The controller may receive input data from the various sensors 16, process the input data, and trigger the actuators 81 based on instructions or codes programmed therein corresponding to one or more routines in response to the processed input data.

[0025] It should be understood that other components may be included in the engine, such as additional valves, sensors, and actuators. In some embodiments, where the engine system 106 is a supercharged engine system, the engine system may also include a supercharging device, such as a turbocharger (not shown).

[0026] Figure 2- Fig. 9 An example configuration is shown by the relative positioning of various components. At least in one example, if it is shown that they are in direct contact or directly coupled to each other, such elements can be referred to as direct contact or directly coupled respectively. Similarly, at least in one example, the elements shown to be continuous or adjacent to each other can be respectively continuous or adjacent to each other. As an example, the components placed in coplanar contact with each other can be referred to as coplanar contact. As another example, in at least one example, the elements separated from each other and having only space without other components therebetween can be referred to as above. As another example, the elements shown above / below each other, on the opposite sides of each other or on the left / right sides of each other can be referred to as above relative to each other. In addition, as shown in the figure, in at least one example, the topmost element or the topmost point of the element can be referred to as the "top" of the component, and the bottommost element or the bottommost point of the element can be referred to as the "bottom" of the component. As used herein, top / bottom, upper / lower, above / below can be relative to the vertical axis (e.g., z-axis) of the accompanying drawings, and are used to describe the positioning of the elements in the accompanying drawings relative to each other. Therefore, in one example, the element shown above other elements is positioned vertically above other elements. As yet another example, the shapes of elements depicted in the drawings may be referred to as having those shapes (e.g., such as annular, straight, planar, curved, rounded, chamfered, angled, etc.). Additionally, in at least one example, elements shown intersecting one another may be referred to as intersecting elements or intersecting one another. Additionally, in one example, an element shown within another element or shown outside another element may be referred to as such.

[0027] 2-4 each illustrate a single component of an exhaust gas sensor connector. Figure 5-Figure 8 Different perspective views and cross-sectional views are shown of the relative arrangement of the components before and after the exhaust gas sensor joint is assembled, and Fig. 9 An example of an exhaust gas sensor connector installed in a vehicle system is shown. Therefore, similar parts are numbered the same and may not be reintroduced. For example, regarding Figure 5-Figure 8 Components described with the same identification labels as those in FIGS. 2-4 are the same components and operate as previously described. Figure 8 A reference axis 299 is included in each of the drawings to facilitate comparison of the views and relative orientations described below.

[0028] FIG. 2 is a side view of a tube 200 that may be included in an exhaust gas sensor connector. Although FIG. 2 shows a two-dimensional view, it should be understood that tube 200 has depth (e.g., in the y-direction referenced to axis 299, which is not visible in FIG. 2). For example, tube 200 may be a hollow cylinder where the diameter of the cylinder varies, as further described below. In some examples, the inner diameter of tube 200 may vary in proportion to the outer diameter of tube 200 so that the thickness of the tube wall remains substantially constant.

[0029] The tube 200 includes a first tube portion 202 having a length 203 that tapers to a reducer (e.g., a reducer coupling) 212, and the first tube portion 202 is coupled to the elbow fitting 207 by the reducer 212. For example, the reducer 212 can be a concentric reducer. The first tube portion 202 is vertical relative to the z-axis of the reference axis 299 and is slightly conical relative to the center axis 201. The first flange 206 is positioned at the bottom end of the first tube portion 202 opposite the reducer 212. For example, the first flange 206 can be an annular rolled flange. The outer diameter and inner diameter of the first tube portion 202 decrease (e.g., taper) upward from the first flange 206 to the reducer 212 along the length 203, so that the outer diameter 208 closer to the first flange 206 is greater than the outer diameter 210 closer to the reducer 212. For example, the first pipe portion 202 can taper inwardly (e.g., toward the central axis 201) from the first flange 206 to the reducer 212 in a range of 1-5 degrees. Thus, the first pipe portion 202 is a tapered pipe. The reducer 212 tapers from the elbow fitting 207 to the first pipe portion 202 so that the outer diameter and inner diameter of the reducer 212 decrease as the distance from the first pipe portion 202 decreases. For example, the reducer 212 can taper outwardly from the central axis 201 in the direction of the elbow fitting 207. In this way, the reducer 212 can have a larger diameter (e.g., outer diameter 209) that matches the diameter of the elbow fitting 207 at the coupling of the reducer 212 to the elbow fitting 207, and a smaller diameter that matches the diameter of the first pipe portion 202 at the coupling of the reducer 212 to the first pipe portion 202. The reducer 212 can be coupled to the elbow fitting 207 via a fastener 213. For example, the fastener 213 can be a fixing pin, a stud, a weld nut, etc. In addition, the fastener 213 can protrude from the tube 200, as will be further described below. In some examples, the reducer 212 can be welded to the first tube portion 202. In other examples, the reducer 212 and the first tube portion 202 can be coupled via a threaded joint.

[0030] As shown in FIG. 2 , the elbow joint 207 can be bent 90 degrees from the reducer 212 to become horizontal relative to the reference axis 299, but other geometries are also possible. The elbow joint 207 is coupled to the second pipe portion 204 at the end opposite to the reducer 212. In some examples, the second pipe portion 204 and the elbow joint 207 can be welded together. In other examples, the second pipe portion 204 and the elbow joint 207 can be coupled via a threaded joint. The outer diameter of the second pipe portion 204 can be the same as the outer diameter 209 of the elbow joint 207. In addition, the outer diameter (and inner diameter) of the second pipe portion 204 can be constant, so that the second pipe portion 204 is a hollow cylinder. For example, the outer diameter 209 of the elbow joint 207 (and the second pipe portion 204) can be greater than the outer diameter 208 of the first pipe portion 202.

[0031] The second pipe portion 204 can be coupled to the third pipe portion 218 via the second flange 214. For example, the second flange 214 can be a threaded flange. In this way, the second flange 214 can couple the third pipe portion 218 to the second pipe portion 204 in a detachable manner. This can enable various sensor components (such as pressure-sensitive elements) to be coupled to the pipe 200 for installation in the exhaust system in the vehicle. For example, the third pipe portion 218 can be used as a joining portion of a pipe (not shown), wherein the third pipe portion 218 is inserted into the pipe. The second flange 214 can be used as a stopper for the pipe so that the pipe does not overlap or engage with the second pipe portion 204. In addition, the second flange 214 can provide a visual mark to ensure that the third pipe portion has been fully inserted into the pipe (for example, engaged in the pipe). For example, the third pipe portion 218 can be inserted into the pipe until the end of the pipe rests against the second flange 214. Further, the pipe can be fixed to the third pipe portion 218 near the second flange 214 (e.g., as shown in FIG. 2, on the right side of the second flange 214) by a clamp around both the pipe and the third pipe portion 218. For example, the pipe can accommodate a pressure-sensitive element of a sensor. For example, the outer diameter (and inner diameter) of the third pipe portion 218 can be substantially similar to the outer diameter (and inner diameter) of the second pipe portion 204, and smaller than the inner diameter of the pipe.

[0032] As shown, the outer diameter 216 of the first flange 206 is larger than the outer diameter 208 and the outer diameter 210 of the first tube portion 202 and the outer diameter 209 of the elbow fitting 207 (and the second tube portion 204). In this way, the first flange 206 can serve as an attachment base for the tube 200 and the remaining components of the exhaust gas sensor fitting, as will be described below. The first flange 206 also has an inner diameter 215, which enables fluid (e.g., exhaust gas) to flow through the first flange 206 and into the tube 200. Once the exhaust gas enters the tube 200, the taper of the first tube portion 202 helps with air flow smoothness and pressure stability through the elbow fitting 207.

[0033] Turning next to FIG. 3 , a side view of a nut assembly 300 having a central axis 301 is shown. Although FIG. 3 is a two-dimensional view, it should be understood that the nut assembly 300 has a depth (e.g., in the y-direction of the reference axis 299, which is not visible in FIG. 3 ). The nut assembly 300 has a length 303 that is less than the length 203 of the first tube portion 202. As indicated by the dashed line, the nut assembly 300 is hollow, having a slightly conical lumen (e.g., an axial bore). For example, the top of the nut assembly 300 has an opening with an inner diameter 308, and the bottom of the nut assembly 300 has an opening with an inner diameter 309 that is less than the inner diameter 308. For example, the lumen of the nut assembly 300 can taper from the inner diameter 308 to the inner diameter 309 in a range of 1 degree to 5 degrees. The taper of the lumen of the nut assembly 300 is in the opposite direction of the taper of the first tube portion 202 of the tube 200 relative to the reference axis 299. The inner diameter 308 and the inner diameter 309 are both larger than the outer diameter 208 of the first pipe portion 202 and smaller than the outer diameter 216 of the first flange 206, so that the nut assembly 300 can be assembled around the first pipe portion 202 instead of around the first flange 206, as will be described with reference to FIG. Figure 5-Figure 8 Described.

[0034] The nut assembly 300 is shown as having a head 306 and a cylindrical threaded bottom 302. As a non-limiting example, the head 306 is hexagonal in shape so that the head 306 can be gripped by a wrench. However, other geometries are also possible. The threaded bottom 302 includes an external thread 304 over a length 305, while the wall of the axial bore of the nut assembly 300 can be smooth. The head 306 has an outer diameter 312, and the threaded bottom 302 has an outer diameter 310. As shown, the outer diameter 312 can be larger than the outer diameter 310. However, in other examples, the outer diameter 312 and the outer diameter 310 can be the same, or the outer diameter 312 can be smaller than the outer diameter 310.

[0035] FIG. 4 shows an inclined view of a boss 400 having a central axis 401. As shown, the boss 400 can be cylindrical. The boss 400 includes a bottom portion 402 that can be welded to an exhaust passage (not shown) of a vehicle. Thus, the boss 400 can serve as a fixed base for fixing the exhaust sensor connector to the exhaust passage. The boss 400 can also include a top surface 408 that is opposite to the bottom portion 402 through a middle portion 406. As will be described below with reference to Figure 5-Figure 8As described in detail, during exhaust gas sensor installation, the tube 200 and the nut assembly 300 can be guided into the boss 400 through the opening in the top surface 408 to form the exhaust gas sensor joint. As shown in FIG4 , the top surface 408 can have a chamfered (e.g., beveled) edge. In other examples, the top surface 408 can have a rounded edge or a right-angled edge.

[0036] The middle portion 406 and the top surface 408 have an outer diameter 414 and include a cylindrical inner cavity with an inner diameter 412. The inner diameter 412 can be a constant diameter throughout the middle portion 406 and can match the outer diameter 310 of the threaded base 302 of the nut assembly 300. In addition, the inner cavity of the middle portion 406 includes an inner thread 404 along the length 405 downward, and thus can be referred to as a female threaded interior in this article. The outer thread 304 of the nut assembly 300 can be formed to engage with the female threaded interior of the boss 400. For example, the length 305 of the threaded base 302 can be substantially similar to the length 405.

[0037] The engagement cavity 410 is formed by the inner cavities of the bottom portion 402 and the middle portion 406. The engagement cavity 410 may have a shape complementary to the first flange 206 of the tube 200, as will be described with reference to FIG. Figure 6 and Figure 8 As further described, the inner diameter 412 is greater than the outer diameter 216 of the first flange 206 , so that the first flange 206 can be assembled through the middle portion 406 without contacting the middle portion 406 . In this way, the first flange 206 can be placed in the engagement cavity 410 without contacting the middle portion 406 .

[0038] Next, Figure 5 A side view of the nut assembly 300 is shown disposed around the first tube portion 202 of the tube 200. During assembly of the sensor connector, both the nut assembly 300 and the tube 200 can be lowered into the female threaded interior (not shown) of the boss 400, as further described below. Prior to coupling the first tube portion 202 to the reducer 212, the nut assembly 300 can be placed around the first tube portion 202 (due to the position of the nut assembly 300, the reducer 212 is located within the tube portion 202). Figure 5 As indicated by arrow 520, nut assembly 300 can freely travel (e.g., slide) up and down first pipe portion 202. First flange 206 prevents nut assembly 300 from sliding off the bottom of pipe 200, as shown in FIG. Figure 6204. In addition, the bending of the elbow fitting 207 can prevent the nut assembly 300 from traveling to the second pipe portion 204. In other examples, such as when the fastener 213 protrudes from the pipe 200, the fastener 213 can prevent the nut assembly 300 from sliding onto the elbow fitting 207, thereby preventing the nut assembly 300 from squeezing the elbow fitting 207 and possibly getting stuck during transportation or maintenance. Further, the nut assembly 300 can freely rotate about a common central axis 501 shared by the nut assembly 300, the first pipe portion 202, and the boss 400. Similarly, the pipe 200 can freely rotate about the common central axis 501. For example, compared to the view shown in FIG. Figure 5 The view shown is rotated as indicated by the y-axis of reference axis 299.

[0039] like Figure 5 As shown, the bottom portion 402 of the boss 400 may have an outer diameter 415 that is smaller than the outer diameter 414 of the middle portion 406. For example, this may help achieve a gas-tight seal when the boss 400 is welded to the exhaust passage. Additionally, due to the radial symmetry of the boss 400, the bottom portion 402 may be welded to the exhaust passage at any rotation relative to the common central axis 501.

[0040] Now go to Figure 6 , shows a second side view highlighting the inner surface of the nut assembly 300 and the boss 400. Figure 5 In comparison, Figure 6 4, both the tube 200 and the nut assembly 300 are rotated relative to the common central axis 501, and the nut assembly 300 is further down the first tube portion, thereby highlighting the vertical movement (as shown by arrow 520) that the nut assembly 300 can make before engaging the boss 400 and the free rotation that the tube 200 and the nut assembly 300 can make. For example, due to the taper of the first tube portion 202 and the taper of the inner cavity of the nut assembly 300, the nut assembly 300 may not contact the first tube portion 202, as indicated by the gap 609 between the inner surface of the nut assembly 300 and the outer surface of the first tube portion 202. The gap 609 has a variable width down the length of the nut assembly 300, and the width further changes as the nut assembly 300 slides up and down the tube 200. For example, as the outer diameter of the first tube portion 202 decreases and the inner diameter of the nut assembly 300 increases, the distance between the outer surface of the first tube portion 202 and the inner surface of the nut assembly 300 increases, which in turn increases the width of the gap 609.

[0041] As mentioned above with respect to FIG. 4 , the middle portion 406 of the boss 400 (e.g., the inner cavity of the boss 400) has an inner diameter 412. The inner diameter 412 is substantially similar to the outer diameter 310 of the threaded base 302 of the nut assembly 300, so that the threaded base 302 fits into the inner cavity of the boss 400. In addition, the internal threads 404 on the length 405 of the inner surface of the middle portion 406 are complementary to the external threads 304 on the length 305 of the threaded base 302 (for clarity, Figure 6 Only a portion of the external thread 304 is shown in FIG. 4 ). For example, the length 405 and the length 305 can be substantially similar, so that when the external thread 304 of the nut assembly 300 is fully engaged with the internal thread 404 of the boss 400, the entire external thread 304 can be assembled within the inner cavity of the boss 400, as shown in FIG. Figure 7 and Figure 8 Described.

[0042] The engagement cavity 410 extends below the inner cavity of the boss 400 and is adapted to receive the first flange 206 of the tube 200. The engagement cavity 410 also includes an angled portion 411 that rises to a top surface 413. The engagement cavity 410 includes an opening having a first smaller inner diameter 416 in the top surface 413 that opens to a second wider inner diameter 418 at the bottom surface of the bottom portion 402. Figure 6 As shown, the opening may have a constant inner diameter 416 for a length 420, which then gradually increases to an inner diameter 418. Figure 8 As further shown, the angled portion 411 may have a shape that is complementary to the inner surface of the first flange 206 of the tube 200 .

[0043] During assembly of the exhaust sensor connector, the first flange 206 of the tube 200 can be inserted into the inner cavity of the boss 400, wherein the first flange 206 is pushed into the engagement cavity 410. Then, the outer thread 304 of the nut assembly 300 can be engaged (e.g., mated) with the inner thread 404 of the boss 400, and the nut is twisted until the bottom surface of the thread bottom 302 pushes the first flange 206. In this way, the first flange 206 can be pressed against the engagement cavity 410 by a downward force, thereby forming a tight seal. It is worth noting that before the first flange 206 is pressed against the engagement cavity 410 by the thread bottom 302, due to the taper of the first tube portion 202 and the taper of the inner cavity of the nut assembly 300, the nut assembly 300 may not contact the first tube portion 202, thereby reducing the amount of friction, horizontal stress, and angular stress applied to the first tube portion 202 when the nut assembly 300 is twisted. Additionally, the tube 200 can remain free to rotate around the common central axis 501 before the first flange 206 is pressed against the engagement cavity 410 by the threaded bottom 302. Once the first flange 206 is pressed against the engagement cavity 410 by the bottom surface of the threaded bottom 302, the tube 200 can be firmly fixed in place and can no longer rotate.

[0044] exist Figure 7 and Figure 8 Two side views of such an assembled exhaust gas sensor connector 700 are shown in FIG. Figure 7 The outer surface is highlighted. Figure 8 A cross-sectional side view is shown highlighting the engagement of the tube 200 and the nut assembly 300 within the boss 400. As described above, the assembled exhaust gas sensor fitting 700 includes the first flange 206 of the tube 200, which is engaged within the boss 400, specifically within the engagement cavity 410 of the boss 400, and is held in place by the nut assembly 300, with the external threads 304 of the nut assembly 300 mating with the internal threads 404 of the boss 400. The threaded bottom 302 of the nut assembly 300 can be positioned within the boss 400 so that the external threads 304 are no longer visible from the outside, as shown. Figure 7 For example, the external thread 304 of the nut assembly 300 can be engaged with the internal thread 404 of the boss 400, and the head 306 of the nut assembly 300 can be twisted until the bottom surface of the thread bottom 302 compresses the first flange 206 of the tube 200 into the engagement cavity 410 of the boss 400. Figure 6 As depicted, the opening in the bottom portion 402 of the boss 400 allows gas to flow into the assembled exhaust gas sensor fitting in the direction of arrow 702 .

[0045] like Figure 8As shown, the inner diameter 215 of the first flange 206 is substantially similar to the diameter of the engagement cavity 410 at the beginning of the angled portion 411. In addition, the slope of the angled portion 411 can follow the slope of the inner surface of the first flange 206, so that the engagement cavity 410 provides a surface that is complementary to the inner surface of the first flange 206. In this way, when the first flange 206 is pressed into the engagement cavity 410 by the bottommost surface of the nut assembly 300, a tight seal can be formed between the first flange 206 of the tube 202 and the engagement cavity 410 of the boss 400. The gap 609 again highlights how the inner cavity of the nut assembly 300 can not contact the first tube portion 202, thereby reducing the amount of stress applied by the nut assembly 300 on the tube 200 during the torqueing process. In addition, the outer diameter 216 of the first flange 206 (shown in Figure 2) is smaller than the inner diameter 412 of the boss 400 (shown in Figures 4 and Figure 6 As shown), the side of the first flange 206 does not contact the wall of the inner cavity of the boss 400.

[0046] In this way, the tube 200 can be inserted into the boss 400 in any rotational orientation relative to the central axis. With the engagement cavity 410 complementarily formed with the first flange 206 and the threaded bottom 302 of the nut assembly 300 complementarily formed with the threaded inner cavity of the boss 400, the exhaust gas sensor connector can be self-aligned when the outer thread 304 of the nut assembly 300 is mated with the inner thread 404 of the boss 400 and the nut is twisted. In addition, at the end of the twisting process, when the bottommost surface of the nut assembly 300 pushes against the first flange 206, the tube 200 can be fixedly held in place, wherein an airtight seal is formed between the first flange 206 and the engagement cavity 410 (and therefore between the tube 200 and the boss 400). This can enable accurate measurements to be made by sensors (such as exhaust pressure sensors) installed in the vehicle via the exhaust gas sensor connector.

[0047] Now go to Fig. 9 , shows an example of an exhaust gas sensor 931 installed in an exhaust system 925. The exhaust system 925 may be included in a vehicle, for example, Figure 1 Specifically, the exhaust gas sensor 931 is installed via the exhaust gas sensor connector 700, which includes a pipe 200, a nut assembly 300, and a boss 400. Fig. 9 and Figure 1 Similar parts of are similarly numbered (e.g., Fig. 9 The exhaust system 925 corresponds to Figure 1 of the exhaust system 125) and may be as previously described with respect to Figure 1 Works as described.

[0048] like Fig. 9As shown, boss 400 is coupled to exhaust passage 935 downstream of emission control device 970 and upstream of exhaust elbow 934. Exhaust system 925 can be attached to the vehicle via hanger 945. Figure 1 Exhaust from the engine 100 of the vehicle can flow from the exhaust manifold to the exhaust passage 935, where, for example, the exhaust gas sensor 926 can measure the oxygen concentration of the exhaust gas. The output of the exhaust gas sensor 926 (such as a voltage output) can be transmitted to the vehicle's controller (e.g., Figure 1 Controller 12). Exhaust pressure sensor 931 can measure the pressure of the exhaust after the exhaust passes through emission control device 970. The output of exhaust pressure sensor 931 (such as a voltage output) can be transmitted to the controller via electrical connection 932.

[0049] As described above, the exhaust pressure sensor 931 can be installed by inserting the bottom flange (e.g., the first flange 206) of the tube 200 into the engagement cavity of the boss 400, mating the external threads of the nut assembly 300 with the internal threads of the boss 400, and then twisting the nut assembly 300 until the nut assembly 300 presses the bottom flange of the tube 200 into the engagement cavity of the boss 400 and firmly holds the tube 200 in place. Before the twisting process is completed, the tube 200 can be rotated within the boss 400, so that the tube 200 can be accurately aligned with the electrical connection 932, for example, while avoiding contact with other vehicle components. As an example, if the tube 200 can only be assembled into the boss 400 in one rotational orientation, such as if the tube 200 includes a notch and the boss 400 includes a corresponding groove, the misalignment of the boss 400 on the exhaust passage 935 may prevent the installation of the tube 200 due to obstruction by other vehicle components (such as the hanger 945). Therefore, it may be necessary to remove, realign, and re-weld boss 400 in order to complete the installation of exhaust pressure sensor 131, thereby increasing the time and cost of the installation process. Since boss 400 is radially symmetrical and the bottom flange of tube 200 is relative to a common central axis (e.g., Figure 5 The common center axis 501 of the boss 400 is assembled into the engagement cavity of the boss 400 in any rotational orientation, so the boss 400 can be welded to the exhaust passage 935 in any rotational orientation without misalignment, thereby reducing installation time and cost.

[0050] Next, Fig.10 A method for measuring an engine system such as Figure 1 Example method 1000 of exhaust pressure in an example engine system 106 of FIG. 1000. For example, an exhaust pressure sensor (such as an exhaust pressure sensor) coupled to an exhaust passage may be used to detect exhaust pressure. Figure 1 The coupling may include an exhaust gas sensor connector (such as an exhaust gas sensor 131) to measure the exhaust pressure. Figure 7-Figure 9 The exhaust gas sensor connector 700 described above is a device for controlling an exhaust gas sensor connector 700, wherein a boss (e.g., boss 400) is fixedly coupled (e.g., welded) to an exhaust passage, and a tube (e.g., tube 200) is fixed to the boss by a nut assembly (e.g., nut assembly 300). Specifically, before the nut assembly is engaged with the boss, the tube may rotate freely within the boss about a central axis, and engaging the nut assembly with the boss may not impose horizontal or angular stress on the tube. Based on instructions stored on a memory of the controller and in conjunction with sensors from an engine system (such as those described above with reference to Figure 1 The sensor (e.g., pressure sensor 131) described above receives a signal, and the controller (e.g., Figure 1 The controller 12 of the engine system may execute instructions for performing portions of the method 1000 and the remainder of the methods included herein. According to the method described below, the controller may employ engine actuators of the engine system to adjust engine operation.

[0051] Method 1000 begins at 1002 and includes performing a process of: Figure 1 The air / fuel mixture is combusted in the cylinder 130 of the cylinder. For example, the air / fuel mixture may be injected into the cylinder 130 via a fuel injector (e.g., Figure 1 The fuel injector 166 of the fuel system (eg, Figure 1 The fuel system 8) delivers fuel to the cylinder, where the fuel is mixed with air and the intake throttle valve (such as Figure 1 The amount of air is controlled by adjusting the opening of the intake throttle 162. In one example, the amount of fuel to be delivered is determined empirically and stored in a predetermined lookup table or function, which can be indexed to engine operating conditions, such as engine speed and engine load, and other engine operating conditions (such as a desired air-fuel ratio). The controller can then determine a pulse width of a control signal to be sent to the fuel injector actuator that corresponds to the determined amount of fuel to be delivered.

[0052] At 1004, method 1000 includes flowing combusted exhaust gas from the cylinder to an exhaust passage. For example, exhaust gas may be exhausted from the cylinder during an exhaust stroke during which the exhaust valve(s) of the cylinder are opened. With the exhaust valve(s) open, exhaust gas may flow from the cylinder to an exhaust manifold (e.g., Figure 1 exhaust manifold 148) and continues to the exhaust passage (eg, Figure 1 Exhaust passage 135).

[0053] At 1006, method 1000 includes measuring the exhaust pressure using an exhaust pressure sensor. Measuring the exhaust pressure using the exhaust pressure sensor also includes flowing the exhaust gas to a pressure sensitive element of the exhaust pressure sensor via an exhaust sensor connector, as indicated at 1008. As described above, if the exhaust sensor connector includes a tube having a tapered portion (e.g., first tube portion 202 of FIG. 3), the exhaust gas can flow to the pressure sensitive element more smoothly than if the tapered portion is not included, resulting in less noise in the pressure measurement. The exhaust pressure sensor can output a voltage corresponding to the exhaust pressure to the controller. After 1008, method 1000 ends.

[0054] In this way, by including a tapered tube terminating in a wider flange and a nut assembly having a slightly conical axial hole (e.g., an inner cavity) and a cylindrical threaded outer portion in the exhaust sensor joint, the tube can rotate freely during the assembly of the exhaust sensor joint. In addition, when the nut assembly is matched with the threaded interior of the boss fixedly coupled to the exhaust passage and is twisted until the bottom surface of the nut assembly presses the wider flange of the tube into the complementary shaped engagement cavity of the boss, the nut assembly will not stress or bend the tapered tube. Due to the free rotation of the tube and the radial symmetry of the boss, the boss can be coupled to the exhaust passage in any rotation, thereby reducing the complexity of the installation process, which can save time and reduce costs. Before the bottom surface of the nut assembly presses the wider flange of the tube into the engagement cavity of the boss, this free rotation of the tube in the boss and the nut assembly enables the tube to be aligned with other vehicle components. In addition, the complementary shape of the wider flange and the engagement cavity, the tapering of the tube, and the slightly conical axial hole of the nut assembly enable self-alignment of the exhaust sensor joint during the installation process.

[0055] The technical effect of including a tapered tube in the exhaust gas sensor connector is that the airflow through the exhaust gas sensor connector can be stabilized and horizontal and angular stresses on the tube can be avoided when assembling the exhaust gas sensor connector.

[0056] As an example, a system includes: a tapered tube having a flange at its wider end; a nut assembly having a head, a cylindrical externally threaded bottom extending downwardly from the head, and a tapered inner cavity adapted to be positioned above the tapered tube; and a boss having a threaded inner cavity adapted to engage with the threaded bottom of the nut assembly, and an engagement cavity extending below the threaded inner cavity adapted to receive the flange. In the previous examples, additionally or alternatively, the boss is fixedly coupled to an exhaust passage of a vehicle system. In any or all of the previous examples, additionally or alternatively, the nut assembly is positioned around the tapered tube. In any or all of the previous examples, additionally or alternatively, the tapered tube and the nut assembly are freely rotatable about a common central axis, and the nut assembly is slidable over the tapered tube above the flange. In any or all of the previous examples, additionally or alternatively, when the flange of the tapered tube is positioned in the engagement cavity of the boss, the tapered tube and the boss form a seal, the threaded bottom of the nut assembly cooperates with the threaded inner cavity of the boss, and the bottommost end of the threaded bottom of the nut assembly presses the flange into the engagement cavity. In any or all of the previous examples, additionally or alternatively, further rotation of the tapered tube is prevented by the bottommost end of the threaded bottom pressing the flange into the engagement cavity.

[0057] As another example, a system includes: an engine including a plurality of cylinders; an intake manifold coupled to the engine for supplying air to the cylinders; an exhaust system including an exhaust manifold coupled to the engine and an exhaust passage coupled to the exhaust manifold; and an exhaust pressure sensor coupled to the exhaust passage via an exhaust sensor connector, the exhaust sensor connector including a tapered tube, a nut assembly having a tapered axial hole, and a boss having a threaded inner cavity suitable for receiving the nut assembly. In the previous examples, additionally or alternatively, the tapered direction of the tapered tube is opposite to the tapered direction of the tapered axial hole of the nut assembly. In any one or all of the previous examples, additionally or alternatively, the tapered tube includes a flange at its wider end, and the nut assembly includes a threaded bottom extending downward from the head, the threaded bottom having a cylindrical external thread. In any one or all of the previous examples, additionally or alternatively, the inner diameter of the tapered axial hole is smaller than the outer diameter of the flange. In any one or all of the previous examples, additionally or alternatively, the inner diameter of the tapered axial hole is larger than the outer diameter of the tapered tube. In any or all of the previous examples, additionally or alternatively, the boss includes an engagement cavity extending below the threaded inner cavity, the engagement cavity is complementarily shaped with the interior of the flange of the tapered tube and includes an opening extending to the bottommost surface of the boss. In any or all of the previous examples, additionally or alternatively, the tapered tube is positioned within the tapered axial bore of the nut assembly, the flange of the tapered tube is inserted into the engagement cavity of the boss, and the threaded bottom of the nut assembly is engaged with the threaded inner cavity of the boss. In any or all of the previous examples, additionally or alternatively, the threaded bottom of the nut assembly is engaged with the threaded inner cavity of the boss by twisting the nut assembly until the bottommost surface of the threaded bottom presses the flange of the tapered tube into the engagement cavity of the boss to form a seal between the flange and the engagement cavity. In any or all of the previous examples, additionally or alternatively, the twisting nut assembly applies a vertical force on the flange of the tapered tube without applying a horizontal or angled force on the tapered tube.

[0058] As another example, a method includes: combusting an air / fuel mixture in a cylinder of an engine; causing the combustion exhaust from the cylinder to flow to an exhaust passage fluidly coupled to the engine; and measuring the pressure of the combustion exhaust by an exhaust pressure sensor coupled to the exhaust passage via an exhaust sensor connector, the exhaust sensor connector including a boss fixedly coupled to the exhaust passage and a tapered tube fixed to the boss by a nut assembly. In the previous examples, additionally or alternatively, the boss includes a cylindrical threaded inner cavity and the nut assembly includes a cylindrical external threaded bottom, the cylindrical external threaded bottom of the nut assembly being formed to engage with the cylindrical threaded inner cavity of the boss. In any or all of the previous examples, additionally or alternatively, the nut assembly includes a tapered inner cavity therethrough, the tapering direction of the tapered inner cavity of the nut assembly is opposite to the tapering direction of the tapered tube, and the nut assembly is positioned around the tapered tube. In any one or all of the previous examples, additionally or alternatively, the cylindrical external thread bottom of the nut assembly cooperates with the cylindrical thread inner cavity of the boss, and the flange at the wider end of the tapered tube is pressed into the engagement cavity by the bottommost surface of the cylindrical external thread bottom of the nut assembly, and the engagement cavity extends below the thread inner cavity of the boss. In any one or all of the previous examples, additionally or alternatively, the pressure sensitive element of the pressure sensor is coupled to the tapered tube.

[0059] In another representation, a method includes: positioning a nut assembly having a tapered inner cavity over a tapered tube, the tapered tube having an annular flange at its wider end so that the inner cavity can slide over the tube over the flange, the nut assembly also having a cylindrical outer thread extending downward from the nut assembly, wherein the inner cavity extends through the nut assembly; inserting the flange into the threaded inner cavity of a base and pushing the flange into an engagement cavity of the base, the engagement cavity extending below the threaded inner cavity; and mating the cylindrical outer thread of the nut assembly with the threaded inner cavity of the base, and twisting the nut until the bottommost end of the cylindrical outer thread pushes against the flange to form a seal between the base and the tapered tube. In a first example of the method, the engagement cavity is complementarily shaped with the inner surface of the flange and includes an opening therethrough. In a second example of the method, which optionally includes the first example, the tapered tube can rotate freely within the threaded inner cavity about a common axis shared by the tapered tube, the nut assembly, and the base until the bottommost end of the cylindrical outer thread pushes against the flange. In a third example of the method which optionally includes one or more of the first and second examples, a pressure sensor is coupled to the tapered tube.

[0060] It should be noted that the example control and estimation routines included herein can be used with various engine and / or vehicle system configurations. The control methods and routines disclosed herein can be stored as executable instructions in a non-volatile memory and can be executed by a control system including a controller combined with various sensors, actuators, and other engine hardware. The specific routines described herein can represent one or more of any number of processing strategies, such as event-driven, interrupt-driven, multi-tasking, multi-threading, etc. Therefore, the various actions, operations, and / or functions shown may be performed in the order shown, performed in parallel, or omitted in some cases. Similarly, the features and advantages of the example embodiments described herein do not necessarily require a processing order, but the processing order is provided for ease of illustration and description. One or more of the actions, operations, and / or functions shown may be repeatedly performed depending on the specific strategy used. In addition, the described actions, operations, and / or functions can graphically represent the code in the non-volatile memory of a computer-readable storage medium that will be programmed into the engine control system, wherein the described actions are performed by executing instructions in a system including various engine hardware components combined with an electronic controller.

[0061] It should be understood that the configurations and routines disclosed herein are exemplary in nature, and these specific embodiments should not be considered limiting, as many variations are possible. For example, the above-described technology can be applied to V-6, I-4, I-6, V-12, opposed 4, and other engine types. The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and configurations and other features, functions, and / or properties disclosed herein.

[0062] The following claims particularly point out certain combinations and subcombinations regarded as novel and non-obvious. These claims may refer to "an" element or "a first" element or the equivalent thereof. Such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties may be claimed by amendment of the present claims or by presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, are also deemed to be included in the subject matter of the present disclosure.

Claims

1. A system comprising: a tapered tube having a flange at its wider end; a nut assembly having a head, a cylindrical externally threaded bottom extending downwardly from the head, and a tapered inner cavity adapted to be positioned above the tapered tube, the tapered inner cavity tapering in a direction opposite to the tapered direction of the tapered tube; and The boss has a threaded inner cavity adapted to engage with the threaded bottom of the nut assembly, and an engaging cavity extending below the threaded inner cavity adapted to receive the flange. 2 . The system of claim 1 , wherein the boss is fixedly coupled to an exhaust passage of a vehicle system. 3 . The system of claim 1 , wherein the tapered inner cavity of the nut assembly has an inner diameter that is smaller than an outer diameter of the flange. 4 . The system of claim 3 , wherein the inner diameter of the tapered lumen of the nut assembly is greater than the outer diameter of the tapered tube.

5. The system of claim 4, wherein the nut assembly is positioned around the tapered tube.

6. The system of claim 5, wherein the tapered tube and the nut assembly are freely rotatable about a common central axis and the nut assembly is slidable over the tapered tube above the flange.

7. The system of claim 6, wherein when the flange of the tapered tube is positioned in the engaging cavity of the boss, the tapered tube and the boss form a seal, the threaded bottom of the nut assembly cooperates with the threaded inner cavity of the boss, and the bottommost end of the threaded bottom of the nut assembly presses the flange into the engaging cavity.

8. The system of claim 7, wherein further rotation of the tapered tube is prevented by the flange being pressed into the engagement cavity by the bottom-most end of the thread base.

9. The system of claim 7, wherein pressing the flange into the engagement cavity through the bottom-most end of the thread base exerts a vertical force on the flange of the tapered tube, but does not exert a horizontal or angular force on the tapered tube.

10. A method comprising: Combusting the air / fuel mixture in the engine's cylinders; flowing combusted exhaust gas from the cylinder to an exhaust passage fluidly coupled to the engine; as well as The pressure of the combustion exhaust is measured by an exhaust pressure sensor coupled to the exhaust passage via an exhaust sensor joint, the exhaust sensor joint including a boss fixedly coupled to the exhaust passage, and a tapered tube fixed to the boss by a nut assembly, the nut assembly being positioned around the tapered tube, the nut assembly including a tapered inner cavity therethrough, the tapered inner cavity tapering in a direction opposite to that of the tapered tube.

11. The method of claim 10, wherein the boss includes a cylindrical threaded interior cavity and the nut component includes a cylindrical externally threaded bottom portion, the cylindrical externally threaded bottom portion of the nut component being shaped to engage the cylindrical threaded interior cavity of the boss.

12. The method according to claim 11, wherein the cylindrical external thread bottom of the nut assembly cooperates with the cylindrical thread inner cavity of the boss, and the flange located at the wider end of the tapered tube is pressed into a coupling cavity by the bottommost surface of the cylindrical external thread bottom of the nut assembly, and the coupling cavity extends below the cylindrical thread inner cavity of the boss.

13. The method of claim 12, wherein a pressure sensitive element of the pressure sensor is coupled to the tapered tube.

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