Intake valve including seal redundancy
By employing a dual-seal design and lubricant in the intake valve, the problem of gas leakage caused by seal wear is solved, resulting in higher sealing performance and equipment reliability, while reducing maintenance frequency and costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CATERPILLAR INC
- Filing Date
- 2022-06-29
- Publication Date
- 2026-07-10
AI Technical Summary
Existing intake valve seals may wear or malfunction, leading to gas leaks, resulting in undesirable downtime and increased maintenance costs.
The valve employs a dual-seal design, including first and second stem seals, which are respectively positioned between the valve stem and the housing and the slender valve guide. Combined with a biasing element and lubricant, this ensures the sliding seal and wear resistance of the valve stem.
It effectively suppresses gas leakage, extends the life of sealing devices and air intake valves, and reduces machine downtime and maintenance costs.
Smart Images
Figure CN117597508B_ABST
Abstract
Description
Technical Field
[0001] This patent invention generally relates to intake valves, and more specifically to sealing methods and sealing devices for intake valves to reduce gas leakage. Background Technology
[0002] Intake valves are used to regulate the flow of gases within the engine. Located between the gas source and the intake manifold, the intake valves regulate the flow of gases entering the intake manifold, where they mix with the incoming air. This mixture flows to the cylinders, where it is then taken in and burned.
[0003] The intake valve includes a seal designed to ensure precise flow through the valve and prevent gas leakage within the valve. Wear or failure of the seal can allow gas to leak through the seal and other parts of the engine. Premature wear or failure of the seal or intake valve can result in undesirable downtime for repair or replacement of the seal or the entire valve.
[0004] Reference U.S. Patent 8,375,902B2 discloses a lift valve having a valve head and a valve stem. According to this reference, the lift valve has two valve seals surrounding the valve stem at the top and bottom of the valve stem to prevent air leakage from the air chamber surrounding the valve stem. Summary of the Invention
[0005] In one aspect, the present invention describes an intake valve assembly for controlling gas flow. The intake valve assembly includes a housing, a valve, an elongated valve guide, and first and second stem seals. The housing includes a central bore defining a central axis and an inlet chamber disposed around said central axis. At least one gas inlet opening and a gas outlet opening open into the inlet chamber. A valve seat is disposed around the gas outlet opening. The gas outlet opening and the valve seat are concentrically disposed around the central axis. The valve includes a valve head and a valve stem. The valve stem has an outer peripheral surface, a distal stem end, and a proximal stem end. The valve head is disposed at the distal stem end of the valve stem. The valve stem is slidably arranged for movement along the central axis to selectively move the valve head to contact and disengage from the valve seat, such that when the valve head contacts the valve seat, the valve head blocks flow between the inlet chamber and the gas outlet opening. The elongated valve guide has a proximal guide end and a distal guide end, and is concentrically disposed around a portion of the valve stem between the valve stem and the central bore of the housing. The valve stem is slidably disposed within the elongated valve guide for movement along the central axis. A first stem seal is located at the distal end of the elongated valve guide, and a second stem seal is located at the proximal end of the elongated valve guide. The first stem seal is configured to seal against the outer peripheral surface of the valve stem between the valve stem and the central bore of the housing, thereby inhibiting flow from the inlet chamber between the valve stem and the housing. The second stem seal is configured to seal against the outer peripheral surface of the valve stem.
[0006] On the other hand, the present invention describes an engine including a pressurized gas source, at least one cylinder, an intake manifold selectively fluidly coupled to the at least one cylinder, and an intake valve assembly for controlling the flow of gas into the intake manifold. The intake valve includes a housing, a valve, an elongated valve guide, and first and second rod seals. The housing includes a central bore defining a central axis and an intake chamber disposed around said central axis. A gas discharge opening and at least one gas inlet opening open into the intake chamber. The at least one gas inlet opening is fluidly coupled to the pressurized gas source. A valve seat is disposed around the gas discharge opening, and the gas discharge opening and the valve seat are concentrically disposed around the central axis. The valve includes a valve head and a valve stem. The valve stem has an outer peripheral surface, a distal stem end, and a proximal stem end. The valve head is disposed at the distal stem end of the valve stem. The valve stem is slidably arranged for movement along the central axis to selectively move the valve head to contact and disengage from the valve seat. When the valve head is not in contact with the valve seat, the gas discharge opening is fluidly connected to the intake manifold, and when the valve head is in contact with the valve seat, the valve head blocks the flow between the inlet chamber and the gas discharge opening. The elongated valve guide has a proximal guide end and a distal guide end, and is concentrically disposed around a portion of the valve stem between the valve stem and the central bore of the housing. The valve stem is slidably disposed within the elongated valve guide for movement along its central axis. A first stem seal is disposed at the distal end of the elongated valve guide, and a second stem seal is disposed at the proximal end of the elongated valve guide. The first stem seal is configured to seal between the outer peripheral surface of the valve stem and the central bore of the housing to suppress flow from the inlet chamber between the valve stem and the housing. The second stem seal is configured to seal with the outer peripheral surface of the valve stem.
[0007] In another aspect, the present invention describes a method for suppressing gas leakage in an intake valve assembly used to control gas flow in an engine. The method includes providing a housing comprising a central bore defining a central axis, an inlet chamber disposed around the central axis, at least one gas inlet opening leading to the inlet chamber, a gas outlet opening leading to the inlet chamber, and a valve seat disposed around the gas outlet opening, the gas outlet opening and the valve seat being concentrically disposed around the central axis. The method further includes disposing an elongated valve guide within the central bore, the valve guide having a tubular structure having a central longitudinal bore; providing a valve including a valve head and a valve stem; and slidably disposing the valve stem within the central longitudinal bore of the valve guide, wherein the valve head is configured to selectively move to contact and disengage from the valve seat to selectively provide gas flow from the at least one gas inlet opening through the inlet chamber to the gas outlet opening. The method further includes disposing a first stem seal between a distal end of the valve guide and a retainer, and sealingly engaging with the outer peripheral surface of the valve stem and the central bore of the housing to suppress flow from the inlet chamber between the valve stem and the housing. The method further includes configuring a second rod seal to seal against the outer peripheral surface of the valve stem and the proximal end of the valve guide. Attached Figure Description
[0008] Figure 1 This is a partial side cross-sectional view of a machine housing an engine, which includes an intake valve incorporating various aspects of the present invention.
[0009] Figure 2 yes Figure 1 An enlarged side cross-sectional view of the intake valve. Detailed Implementation
[0010] This invention relates to an intake valve assembly 100 for an engine 102 of a machine 104. It should be understood that the device disclosed herein has universal applicability in various types of machines, including mobile and stationary machines. The term "machine" can refer to any machine that performs some type of operation associated with an industry such as mining, construction, farming, transportation, or any other industry known in the art. For example, a machine can be an earthmoving machine, such as a wheel loader, excavator, dump truck, backhoe excavator, motorized grader, material handling machine, etc.
[0011] Engine 102 may include one or more cylinders 106. Although in Figure 1 Only one cylinder is shown, but engine 102 may include multiple such cylinders 106. Intake manifold 108 may be provided with a compressed air source that can be selectively supplied to cylinders 106 through opening 110. Compressed air can be supplied to intake manifold 108 by any suitable means; in the illustrated embodiment, the flow is provided from chamber 112. Intake valve 114 can be selectively operated to move intake valve cover 116 to open or close opening 110 between intake manifold 108 and cylinders 106, thereby selectively fluidly connecting intake manifold 108 to cylinders 106. Within cylinder 106, a mixture of air and fuel or gas can be combusted.
[0012] To selectively control the flow of fuel or gas for mixing with compressed air to the intake manifold 108 (generally shown as 118), an intake valve assembly 100 is provided to selectively supply gas flow 118 through an opening 120 in the intake manifold 108. (Refer to...) Figure 2The intake valve assembly 100 includes a housing 122 having a central bore 124 defining a central axis 126. The housing 122 further includes an inlet chamber 128 along the central axis 126. To allow gas to pass through the inlet chamber 128, the housing 122 includes at least one gas inlet opening 130 and a gas outlet opening 132, both opening into the inlet chamber 128. In the illustrated embodiment, the gas inlet opening 130 is fluidly coupled to a gas supply 118, while the gas outlet opening 132 is configured to provide gas flow 118 to the intake manifold 108 through an opening 120 of the intake manifold 108. The gas outlet opening 132 defines a valve seat 134, and the gas outlet opening 132 and the valve seat 134 are concentric about the central axis 126.
[0013] To selectively open and close the gas discharge opening 132, a valve 140 is slidably disposed in a central bore 124 of a housing 122 along a central axis 126. The valve 140 includes a valve head 142 and a valve stem 144. The valve stem 144 is an elongated structure including an outer peripheral surface 146, a distal stem end 148, and a proximal stem end 150. The valve head 142 is disposed at the distal stem end 148 of the valve stem 144. As the valve stem 144 moves within the central bore 124 of the housing 122 along the central axis 126, the valve head 142 can selectively move to contact and disengage from the valve seat 134. Thus, when the valve head 142 rests against the valve seat 134, the intake valve assembly 100 prevents gas from flowing from the intake chamber 128 through the gas discharge opening 132 into the intake manifold 108 via the opening 120. Conversely, when the valve head 142 is not seated against the valve seat 134, the intake valve assembly 100 allows gas to flow from the gas supply 118 into the intake chamber 128 through at least one gas inlet opening 130, and from the intake chamber 128 into the intake manifold 108 through the gas outlet opening 132 into the opening 120.
[0014] The movement of valve 140 can be provided by any suitable mechanism. See again... Figure 1In the illustrated embodiment, movement of valve 140 is provided by an actuation assembly (generally designated 152). Actuation assembly 152 includes a rotatably mounted cam 154. As cam 154 rotates, cam follower 156 provides linear movement to lifter 158, which engages a first end 160 of first push rod 162 to provide axial movement to push rod 162. A second end 164 of push rod 162 is coupled to a first rocker arm 166, which is pivotally mounted about axis 168. The first rocker arm 166 is also coupled to a second push rod 170. As the first rocker arm 166 pivots due to the axial movement of the first push rod 162, the first rocker arm 166 also moves the second push rod 170. The second push rod 170, as well as the proximal rod end 150 of valve 140, is coupled to a second rocker arm 172, which is pivotally mounted at axis 174. When the second push rod 170 pivots the second rocker arm 172, an axial force is applied to the valve stem 144 to move the valve 140 in the distal direction so that the valve head 142 leaves the valve seat 134, thereby opening the flow from the inlet chamber 128 to the intake manifold 108.
[0015] Back to Figure 2 To provide a tight seal between the valve head 142 and the valve seat 134 when the valve assembly 100 is closed, one or more biasing elements 176 may be provided. In the illustrated embodiment, a spring assembly 178 comprising two springs and a rotating coil is provided. The proximal end 180 of the spring assembly 178 is coupled to the valve stem 144, while the distal end 182 of the spring assembly 178 is disposed toward the base surface 184 of the housing 122. Thus, the biasing elements 176 (here, the spring assembly 178) apply force to bias the valve 140 in a proximal direction within the housing 122, i.e., bias the valve head 142 against the valve seat 134.
[0016] To maintain precise flow of gas through the inlet chamber 128, the valve assembly 100 is provided with a double sealing device. The sealing device includes a first stem seal 190 and a second stem seal 192. To position the first and second stem seals 190 and 192, an elongated valve guide 194 is positioned between the valve stem 144 and the central bore 124 of the housing 122. The elongated valve guide 194 includes a proximal guide end 196 and a distal guide end 198, and is concentrically arranged around a portion of the valve stem 144. The valve stem 144 is slidably disposed within the elongated valve guide 194 for movement along the central axis of the valve guide 194, which coincides with the central axis 126 of the housing 122.
[0017] A first stem seal 190 is disposed between the valve stem 144 and the central bore 124 of the housing 122. Specifically, the first stem seal 190 is provided with a first sealing element 191 that sealably engages with the outer peripheral surface 146 of the valve stem 144 and the central bore 124 of the housing 122 to suppress flow from the inlet chamber 128 between the valve stem 144 and the housing 122. The first sealing element 191 can be formed of any suitable material, such as, for example, neoprene rubber. During assembly, the first stem seal 190 is positioned within the central bore 124. A retainer 200 is then positioned within the inlet chamber 128, abutting against the proximal inner surface 202 of the inlet chamber 128.
[0018] The second stem seal 192 is disposed proximal to the first stem seal 190 to provide a seal between the proximal guide end 196 and the valve stem 144. The second stem seal 192 includes a second sealing element 193 that maintains a sealing engagement at the proximal guide end 196 along the outer peripheral surface 146 of the valve stem 144.
[0019] The second sealing element 193 can be held in place by a support 204. The support 204 may include a vertical element 206 and a horizontal element 208. In at least one embodiment, the vertical element 206 has a tubular structure, while the horizontal element 208 is a flange extending outward at an angle substantially perpendicular to the vertical element. To hold the support 204 in place, the horizontal element 208 may be disposed between the distal end 182 of the spring assembly 178 and the base surface 184 of the housing 122, with a biasing element 196 applying a holding force to the horizontal element 208. Thus, the vertical element 206 can be positioned substantially parallel to the valve stem 144, thereby maintaining contact of the second sealing element 193 along the valve stem 144, which can translate along the central axis 126.
[0020] According to another aspect of the invention, to facilitate smooth translation of the valve stem 144 within the elongated valve guide 194, the second rod seal 192 can provide metering of lubricant between the valve stem 144 and the elongated valve guide 194. That is, lubricant (e.g., lubricating oil) can be provided along the outer surface of the valve stem 144, and the second rod seal 192 only allows a metered amount of lubricant to pass between the valve stem 144 and the elongated valve guide 194. While lubricant can be provided to the proximal rod end 150 by any suitable means, in the illustrated embodiment, although alternative means may be provided, it can be provided through the cavity 210 of the second push rod 170 (see...). Figure 1 Supply lubricant.
[0021] Industrial applicability
[0022] The present invention applies to an intake valve assembly 100, which can be used in the engine 102 of various mobile and stationary machines 104 to suppress gas leakage.
[0023] In at least some embodiments, the use of dual seals allows for an enhanced sealing strategy. The top seal can perform a metering oil function, which lubricates the bottom seal and allows the bottom seal to operate optimally for extended periods. The top seal can also function as a gas seal in case of wear or failure of the bottom seal, acting as an auxiliary gas seal in the event of leakage through the bottom seal.
[0024] In at least some embodiments, the disclosed apparatus can extend the life of the sealing device to suppress valve failure and extend the life of the associated intake valve. Thus, at least some of the disclosed embodiments can minimize machine downtime and delays in repair or replacement, and the associated costs.
[0025] It should be understood that the foregoing description provides embodiments of the disclosed systems and techniques. However, it is conceivable that other implementations of the invention may differ in detail from the foregoing embodiments. All references to the invention or embodiments thereof are intended to refer to the specific embodiments discussed at that point and are not intended to imply any limitation on the scope of the invention in a broader sense. All language used to distinguish and derogatoryly describe certain features is intended to indicate a lack of preference for those features, but does not, unless otherwise specified, exclude them entirely from the scope of the invention.
[0026] Unless otherwise stated herein, the descriptions of numerical ranges herein are intended only as a shorthand for individually referring to each individual value falling within that range, and each individual value is incorporated into the specification as if it were described individually herein. All methods described herein may be performed in any suitable order unless otherwise stated herein or clearly contradicted by the context.
[0027] The terms “a,” “an,” “the,” and “at least one,” and similar designations used in the context of describing the invention (particularly in the context of the appended claims) should be interpreted to cover both the singular and the plural, unless otherwise stated herein or obviously contradicted by the context. The use of the term “at least one” followed by a list of one or more items (e.g., “at least one of A and B”) should be interpreted to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B), unless otherwise stated herein or obviously contradicted by the context.
[0028] Therefore, this invention includes all modifications and equivalents of the subject matter described in the appended claims as permitted by applicable law. Furthermore, unless otherwise stated herein or clearly contradicted by the context, the foregoing elements are covered by this invention in all possible combinations of their variations.
Claims
1. An intake valve (140) assembly (100) for controlling gas flow, the intake valve (140) assembly (100) comprising: A housing (122) includes a central hole (124) defining a central axis (126), an inlet chamber (128) disposed around the central axis (126), at least one gas inlet opening (130) leading to the inlet chamber (128), a gas outlet opening (132) leading to the inlet chamber (128), and a valve seat (134) disposed around the gas outlet opening (132), the gas outlet opening (132) and the valve seat (134) being concentrically disposed around the central axis (126); A valve (140) includes a valve head (142) and a valve stem (144), the valve stem (144) having an outer peripheral surface (146), a distal stem end (148) and a proximal stem end (150), the valve head (142) being disposed at the distal stem end (148) of the valve stem (144), the valve stem (144) being slidably arranged for movement along the central axis (126) of the housing (122) to selectively move the valve head (142) to contact and discontinuate contact with the valve seat (134), the valve head (142) blocking flow between the inlet chamber (128) and the gas outlet opening (132) when in contact with the valve seat (134); An elongated valve guide (194) having a proximal guide end (196) and a distal guide end (198) is concentrically disposed around a portion of the valve stem (144) between the valve stem (144) and the central hole (124) of the housing (122), the valve stem (144) being slidably disposed within the elongated valve guide (194) for movement along the central axis (126); A first rod seal (190) is disposed distal to the elongated valve guide (194) and sealably engages with the outer peripheral surface (146) of the valve stem (144) and the central hole (124) of the housing (122) to suppress flow from the inlet chamber (128) between the valve stem (144) and the housing (122); as well as A second rod seal (192) is configured to seal against the outer peripheral surface (146) of the valve stem (144) and the proximal guide end (196).
2. The intake valve (140) assembly (100) according to claim 1, wherein the second rod seal (192) inhibits gas flow between the valve stem (144) and the elongated valve guide (194) and measures lubricant flow between the valve stem (144) and the elongated valve guide (194).
3. The intake valve (140) assembly (100) according to claim 1, further comprising a retainer (200) disposed within the intake chamber (128) surrounding the valve stem (144).
4. The intake valve (140) assembly (100) according to claim 1, wherein the second rod seal (192) includes a second sealing element (193) and a support (204), wherein the support (204) holds the second sealing element (193) around the outer peripheral surface (146) of the valve stem (144), substantially adjacent to the proximal guide end (196).
5. The intake valve (140) assembly (100) according to claim 4, wherein the support (204) comprises a vertical element (206) and a horizontal element (208), the vertical element (206) being arranged substantially parallel to the valve stem (144) to maintain the second sealing element (193) in contact along the valve stem (144), and the horizontal element (208) being arranged substantially adjacent to the housing (122).
6. The intake valve (140) assembly (100) according to claim 5, wherein the vertical element (206) is a tubular structure including a supporting peripheral surface (146), and the horizontal element (208) is a flange extending at an angle substantially perpendicular to the supporting peripheral surface (146) of the vertical element (206).
7. The intake valve (140) assembly (100) according to claim 1, further comprising a biasing element (176) coupled to the proximal stem end (150), the biasing element (176) applying a retaining force to bias the valve head (142) into contact with the valve seat (134).
8. The intake valve (140) assembly (100) according to claim 7, wherein the housing (122) includes a base surface (184) and the biasing element (176) is configured to apply the retaining force to the valve stem (144) between the base surface (184) and the proximal stem end (150).
9. The intake valve (140) assembly (100) according to claim 8, wherein the second stem seal (192) includes a second sealing element (193) and a support (204), wherein the support (204) includes a vertical element (206) and a horizontal element (208), the vertical element (206) being configured substantially parallel to the valve stem (144) and holding the second sealing element (193) around the outer peripheral surface (146) of the valve stem (144), substantially adjacent to the proximal guide end (196), and the horizontal element (208) being disposed between the biasing element (176) and the base surface (184).
10. An engine (102), comprising: Pressurized gas source (118); At least one cylinder (106); An intake manifold (108) selectively fluidly connected to the at least one cylinder (106); and The intake valve (140) assembly (100) according to any one of claims 1-9, wherein the at least one gas inlet opening (130) is fluidly connected to the pressurized gas source (118), and the gas outlet opening (132) is selectively fluidly connected to the intake manifold (108).