Adaptive exhaust valve with purpose-designed spring

Patent metadata

Field	Value
Publication number	US-11384666-B2
Application number	US-201916669022-A
Country	US
Kind code	B2
Filing date	Oct 30, 2019
Priority date	Oct 30, 2019
Publication date	Jul 12, 2022
Grant date	Jul 12, 2022

Abstract

An internal combustion engine system includes a combustion engine configured to produce exhaust gases as a product of a combustion reaction. An exhaust discharge pipe coupled to the internal combustion engine, and an adaptive valve assembly. The adaptive valve assembly is coupled to the exhaust discharge pipe and configured to receive the exhaust gases prior to the exhaust gases reaching the atmosphere. The adaptive valve assembly includes a valve flapper arranged in the passageway and configured to pivot about a flapper pivot axis from a normally-closed position to an opened position.

First claim

The invention claimed is:

1. An adaptive valve assembly comprising
a pipe defining a passageway,
a valve flapper arranged in the passageway and configured to pivot about a flapper pivot axis from a normally-closed position to an opened position, and
a flapper mount assembly configured to couple the valve flapper to the pipe for movement about the flapper pivot axis from the normally-closed position to the opened position, the flapper mount assembly including a bushing system having a thrust bushing and a barrel bushing opposite the thrust bushing relative to the valve flapper, a valve shaft coupled to the valve flapper and supported axially and radially by the thrust bushing and radially by the barrel bushing to allow rotation of the valve flapper about the flapper pivot axis, and a resilient member configured (i) to apply a torsional force about the flapper pivot axis on the valve shaft to bias the valve flapper toward the normally-closed position and (ii) to apply a force on the valve shaft to bias the valve shaft generally along the flapper pivot axis into engagement with the thrust bushing and laterally about a lateral axis at the thrust bushing into engagement with a downstream side of the barrel bushing so that shaft-to-bearing chatter is reduced.

2. The adaptive valve assembly of claim 1 , wherein the resilient member is a bias spring that includes a first end, a second end, and a plurality of coils between the first end and the second end, wherein the plurality of coils are shaped to provide a spring force with an asymmetrical axial load generally along the flapper axis on the valve shaft.

3. The adaptive valve assembly of claim 2 , wherein the asymmetrical load includes a first axial force imparted by the upstream side of the bias spring and a second axial force imparted by the downstream side of the bias spring, the second axial force being greater than the first axial force.

4. The adaptive valve assembly of claim 3 , the plurality of coils are closed along an upstream side of the bias spring and opened along a downstream side of the bias spring.

5. The adaptive valve assembly of claim 3 , wherein the plurality of coils of the bias spring includes a top spring coil, a bottom spring coil, and a plurality of body coils between the top-spring coil and the bottom-spring coil and each of the plurality of body spring coils is arranged a first distance relative to one another along an upstream side of the bias spring and is arranged a second distance from one another along a downstream side of the bias spring, the second distance being greater than the first distance.

6. The adaptive valve assembly of claim 4 , further comprising a spring retainer including an outer spring housing coupled to the valve shaft in a fixed position for rotation with the valve shaft and an inner spring housing coupled in a fixed position relative to the valve shaft and the outer spring housing.

7. The adaptive valve assembly of claim 6 , wherein the first end of the bias spring extends away from the plurality of coils and into a first projection-receiving space formed in the outer spring housing and the second end of the bias spring extends away from the plurality of coils and into a second projection-receiving space formed in the inner spring housing that is spaced 180 degrees from the first projection-receiving space around a circumference of each of the coils to orient the spring relative to the valve shaft.

8. The adaptive valve assembly of claim 6 , wherein each of the plurality of coils are concentric and the first end and the second end are interchangeable to provide a poka-yoke with the outer spring housing and the inner spring housing so that the valve shaft is always biased into engagement with the downstream side of the barrel bushing.

9. The adaptive valve assembly of claim 1 , wherein the bias spring includes a plurality of coils that extend circumferentially about a spring axis and the coils are spaced apart from the spring axis by a first distance along a downstream side of the bias spring and the coils are spaced apart from the spring axis by a second distance that changes along an axial length of the bias spring relative to the spring axis.

10. The adaptive valve assembly of claim 1 , wherein the bias spring includes a top-planar coil, a bottom planar coil spaced apart from the top planar coil and a plurality of open coils between the top planar coil and the bottom planar coil and the top planar coil is offset from the bottom planar coil to provide a lateral force against the valve shaft.

11. An internal combustion engine system comprising
an internal combustion engine configured to produce exhaust gases as a product of a combustion reaction,
an exhaust discharge pipe coupled to the internal combustion engine and defining a passageway that is configured to direct the exhaust gases from the internal combustion engine to atmosphere, and
an adaptive valve assembly coupled to the exhaust discharge pipe and configured to receive the exhaust gases prior to the exhaust gases reaching the atmosphere, the adaptive valve assembly comprising
a valve flapper arranged in the passageway and configured to pivot about a flapper pivot axis from a normally-closed position to an opened position and
a flapper mount assembly configured to couple the valve flapper to the pipe for movement about the flapper pivot axis from the normally-closed position to the opened position, the flapper mount assembly including a bushing system having a thrust bushing and a barrel bushing opposite the thrust bushing relative to the valve flapper, a valve shaft coupled to the valve flapper and supported axially and radially by the thrust bushing and radially by the barrel bushing to allow rotation of the valve flapper about the flapper pivot axis, and a resilient member configured (i) to apply a torsional force about the flapper pivot axis on the valve shaft to bias the valve flapper toward the normally-closed position and (ii) to apply a force on the valve shaft to bias the valve shaft generally along the flapper pivot axis into engagement with the thrust bushing and laterally about a lateral axis at the thrust bushing into engagement with a downstream side of the barrel bushing so that shaft-to-bearing chatter is reduced.

12. The internal combustion engine system of claim 11 , wherein the resilient member is a bias spring that includes a first end, a second end, and a plurality of coils between the first end and the second end, wherein the plurality of coils are shaped to provide a spring force with an asymmetrical axial load generally along the flapper axis on the valve shaft.

13. The internal combustion engine system of claim 12 , wherein the asymmetrical load includes a first axial force imparted by the upstream side of the bias spring and a second axial force imparted by the downstream side of the bias spring, the second axial force being less than the first axial force.

14. The internal combustion engine system of claim 13 , the plurality of coils are closed along an upstream side of the bias spring and opened along a downstream side of the bias spring.

15. The internal combustion engine system of claim 13 , wherein the plurality of coils of the bias spring includes a top spring coil, a bottom spring coil, and a plurality of body coils between the top-spring coil and the bottom-spring coil and each of the plurality of body spring coils is arranged a first distance relative to one another along an upstream side of the bias spring and is arranges a second distance from one another along a downstream side of the bias spring.

Assignees

• Faurecia Emissions Control Technologies Usa Llc

Inventors

• Sims Keith
• Wang Yuntian
• Schepman Eric
• Wu Wenqi

Classifications

• F01N1/18

  having rotary movement · CPC title

• F01N2240/36

  an exhaust flap · CPC title

• F01N1/163 Primary

  by means of valves · CPC title

• F16K31/566

  using a bistable spring device arranged symmetrically around the actuating stem · CPC title

• F16K31/5282

  comprising a pivoted disc or flap · CPC title