Switchable valve bridge

Abstract

The invention relates to a switchable valve bridge. A switchable valve bridge for an internal combustion engine is provided that includes an outer housing, an inner housing, a locking collar, and a first ramp. The outer housing includes two valve pallets configured to engage with the two poppet valves. The inner housing is slidably disposed within the outer housing. The inner housing has a first locking bolt configured to move radially relative to an actuation axis of the inner housing. The locking collar is configured to move axially in a first axial direction parallel to the actuation axis via an actuation force applied to the locking collar. A first ramp is disposed within both the first locking aperture and the locking collar. The first ramp is configured to be actuated by the locking collar such that axial movement of the first ramp causes radial movement of the first locking bolt.

Description

Technical Field

[0001] The present invention relates to a valve bridge for an internal combustion engine. More particularly, the present invention relates to a switchable valve bridge that can be utilized to perform valve deactivation or variable valve lift on an internal combustion engine. Background Art

[0002] Current valve actuators for internal combustion (IC) engines utilize a valve bridge disposed between a rocker arm and a pair of poppet valves. Disabling the poppet valves or adjusting the lift height of the poppet valves can benefit the performance, efficiency, and emissions of IC engines. Summary of the invention

[0003] An example embodiment of a switchable valve bridge for an internal combustion engine is provided, the switchable valve bridge comprising an outer housing, an inner housing, a locking collar and a first ramp. The outer housing comprises a first valve support plate configured to engage with a first poppet valve, a second valve support plate configured to engage with a second poppet valve and a first locking hole. The inner housing is slidably disposed in the outer housing. The inner housing has a first locking bolt configured to move radially relative to an actuation axis of the inner housing. The locking collar is configured to move axially in a first axial direction via an actuation force applied to the locking collar. The first ramp may be disposed in both the first locking aperture and the locking collar. The first ramp is configured to be actuated by the locking collar so that axial movement of the first ramp causes radial movement of the first locking bolt. The first ramp may be configured to directly engage the first locking bolt.

[0004] In an exemplary first locked position of the switchable valve bridge, the first locking bolt engages the first locking aperture such that the inner housing is locked to the outer housing. In another aspect, the first locking bolt can include a flat surface configured to engage a flat surface of the locking aperture.

[0005] In an exemplary second locked position of the switchable valve bridge, the first locking bolt is in a radially inward position such that the inner housing is unlocked from the outer housing.

[0006] In an exemplary embodiment, the first ramp includes a tapered interface that engages the first locking bolt. In another aspect, the tapered interface engages a curved surface of the first locking bolt.

[0007] In an example embodiment, the switchable valve bridge includes a mechanical clearance adjustment ring disposed between the inner housing and the outer housing. The mechanical clearance adjustment ring is configured to be selectively installed to adjust the axial position of the inner housing relative to the outer housing. In another aspect, the clearance adjustment ring is selected from one of a plurality of clearance adjustment ring groups to achieve a predetermined mechanical clearance between the inner housing and the outer housing, and the plurality of clearance adjustment ring groups are classified according to thickness.

[0008] In an example embodiment, the switchable valve bridge may include a return spring configured to move the locking collar in the second axial direction when the actuation force is less than the force of the return spring. In another aspect, the return spring may engage a ramp or the locking collar.

[0009] In an exemplary embodiment, the switchable valve bridge may include a lost motion spring disposed between the inner housing and the outer housing. In another aspect, the lost motion spring is disposed in a hole of the outer housing such that the inner housing and the lost motion spring are disposed in series in the hole.

[0010] In an example embodiment, the inner housing includes a protrusion extending outside of the bore of the outer housing, and the protrusion includes a rocker arm interface configured to directly engage the rocker arm.

[0011] In an exemplary embodiment, the outer shell includes a second locking aperture, the second locking bolt is configured to engage the second locking aperture in the first locking position, and the second ramp is disposed in the second locking aperture. The second ramp can be configured to directly engage the second locking bolt and be actuated by the locking collar. In another aspect, the first ramp and the second ramp are separate components.

[0012] In the exemplary embodiment, the actuation force does not come from pressurized hydraulic fluid.

[0013] In an example embodiment, the locking collar is configured to be slidably guided by an outer surface of the extension.

[0014] An example embodiment of a switchable valve bridge system for an internal combustion engine includes an electric actuator, an arm configured to be actuated by the electric actuator, and a switchable valve bridge. The switchable valve bridge includes an outer housing that: i) is configured to actuate two poppet valves, and ii) has an extension that includes a locking orifice. The switchable valve bridge also includes an inner housing slidably disposed in a hole in the extension, a locking collar engaged with the arm, and a ramp disposed in the locking collar. The inner housing has a locking bolt configured to move radially relative to an actuation axis of the inner housing. The locking collar is configured to move axially via an actuation force from the arm via the electric actuator. The ramp is configured to be actuated by the locking collar so that the axial movement of the ramp causes the locking bolt to move radially from a first locked position to a second unlocked position, in which the locking bolt engages the locking orifice and in which the inner housing is unlocked from the outer housing.

[0015] In an example embodiment, the arm includes two fingers that extend on opposite sides of the outer housing and engage the locking collar. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a perspective view of an example embodiment of a switchable valvetrain system including a switchable valve bridge.

[0017] Figure 2 yes Figure 1 A three-dimensional view of the switchable valve bridge.

[0018] Figure 3 It is taken from Figure 2 A cross-sectional view of the top of the switchable valve bridge.

[0019] Figure 4 is a perspective view of an example embodiment of a mechanical lash adjuster.

[0020] Figure 5 is a perspective view of an example embodiment of an inner housing retaining ring.

[0021] Figure 6 yes Figure 1 A perspective view of an example embodiment of an outer housing of a switchable valve bridge.

[0022] Figure 7 yes Figure 1 A perspective view of an example embodiment of a spring collar of a switchable valve bridge.

[0023] Figure 8 yes Figure 1 A perspective view of an example embodiment of an inner housing of a switchable valve bridge.

[0024] Fig. 9 yes Figure 1 A perspective view of an example embodiment of a locking collar of a switchable valve bridge.

[0025] Fig. 10A yes Figure 1 A perspective view of an example embodiment of a first ramp of a switchable valve bridge.

[0026] Fig. 10B yes Figure 1 A perspective view of an example embodiment of a second ramp of a switchable valve bridge.

[0027] Fig.11 yes Figure 1 A perspective view of an example embodiment of a locking bolt retaining ring of a switchable valve bridge.

[0028] Fig.12 yes Figure 1 A perspective view of an example embodiment of a circlip of a switchable valve bridge.

[0029] Fig.13A It is taken from Figure 2 A sectional view of the switchable valve bridge in a first locked position or a first locked state.

[0030] Fig. 13B It is taken from Figure 2 A sectional view of the switchable valve bridge in which the switchable valve bridge is in a second unlocked position or a second unlocked state. DETAILED DESCRIPTION

[0031] Embodiments of the present invention are described herein. It should be appreciated that the same reference numerals appearing in different figures represent identical or functionally similar structural elements. In addition, it should be understood that the embodiments of the invention are merely examples, and other embodiments may take various alternative forms. These figures are not necessarily in proportion; some features may be exaggerated or minimized to show the details of a particular component. Therefore, the specific structural and functional details of the invention herein should not be interpreted as limiting, but only as a representative basis for teaching those skilled in the art to use the embodiments in various ways. As will be understood by those of ordinary skill in the art, the various features illustrated and described with reference to any one of the figures may be combined with the features illustrated in one or more other figures to produce an embodiment that is not explicitly illustrated or described. The combination of the features shown provides a representative embodiment for a typical application. However, for a particular application or implementation, various combinations and modifications of features consistent with the teachings of the present invention may be required.

[0032] The terms used herein are only used to describe the purpose of specific aspects, and are not intended to limit the scope of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as those generally understood by those of ordinary skill in the art to which the present invention belongs. Although any method, device or material similar to or equal to those described herein can be used in practice or testing the present invention, the following exemplary methods, devices and materials are now described.

[0033] Figure 1 A perspective view of an example embodiment of a switchable valvetrain system 100 including a switchable valve bridge 40 is shown. Figure 2 A perspective view of the switchable valve bridge 40 is shown. Figure 3 A cross-sectional view of the top of the switchable valve bridge 40 is shown. Figure 4 and Figure 5 Perspective views of the mechanical lash adjuster 38 and the inner housing retaining ring 34 are shown respectively. Figure 6 A perspective view of the outer housing 42 of the switchable valve bridge 40 is shown. Figure 7 A perspective view of the spring collar 94 of the switchable valve bridge 40 is shown. Figure 8 A perspective view of the inner housing 60 of the switchable valve bridge 40 is shown. Fig. 9 A perspective view of the locking collar 70 of the switchable valve bridge 40 is shown. Fig. 10A and Fig. 10B A perspective view of the first ramp 80A and the second ramp 80B of the switchable valve bridge 40 are shown, respectively. Fig.11 A perspective view of a locking bolt retaining ring 90 of a switchable valve bridge 40 is shown. Fig.12 A perspective view of a circlip 92 of the switchable valve bridge 40 is shown. Fig.13A Shown is taken from Figure 2 sectional view of the switchable valve bridge 40 in the first locked position. Fig. 13B Shown is taken from Figure 2 sectional view of the switchable valve bridge 40 in the second unlocked position. The following discussion should refer to Figures 1 to 13B Reading.

[0034] The switchable valve train system 100 includes a rocker arm 12, a camshaft 10, a switchable valve bridge 40, a pair of valve springs 14 corresponding to a pair of poppet valves 16, an actuator 20, an arm 28, and a bracket 26. The actuator 20 may be an electric actuator that electronically communicates with a controller (not shown) via an electrical connector 21. The actuator pin 22 of the actuator 20 engages with a first end 29 of the arm 28. The arm 28 is slidably guided by the bracket 26, which is fixed to a cylinder head (not shown) of an internal combustion engine via a fastener 18. The second end 30 of the arm 28 is defined by a first finger 31A and a second finger 31B. The arm 28 can be described as being divided into two fingers that define the second end 30. The first finger 31A and the second finger 31B engage opposite sides of the locking collar 70 of the switchable valve bridge 40.

[0035] The switchable valve bridge 40 includes an outer housing 42 having a first arm 44A, a second arm 44B, and an extension 48. The first arm 44A includes a first valve carrier plate 46A that engages one of the two poppet valves 16, and the second arm 44B includes a second valve carrier plate 46B that engages the other of the two poppet valves 16. It can be said that the first arm 44A and the second arm 44B define an opposing arrangement. The extension 48 can be described as being in the form of a tubular and extending in a direction away from the rocker arm 12 or in the first direction D1. The first finger 31A and the second finger 31B of the arm 28 extend on opposite sides of the outer housing 42 of the switchable valve bridge 40, or more specifically, on opposite sides of the extension 48 of the outer housing 42. Alternatively, the first finger 31A and the second finger 31B are located on both sides of the extension 48. The outer housing 42 includes a hole 52 extending between the first arm 44A and the second arm 44B and extending longitudinally within the extension 48. The hole defines a cylindrical wall 47 of the extension 48. The extension 48 of the outer housing 42 includes a first locking aperture 49A and a second locking aperture 49B extending through the wall 47 of the extension formed by the hole 52. The open end of the hole 52 includes a retaining groove 43 for the inner housing retaining ring 34 and a clearance step 45 for a mechanical clearance adjuster 38 in the form of a mechanical clearance adjustment ring 36. The inner housing retaining ring 34 is directly engaged by the mechanical clearance adjustment ring 36. There may be any suitable number of mechanical clearance adjustment rings 36.

[0036] The switchable valve bridge 40 includes an inner housing 60, which is disposed in the bore 52 of the outer housing 42 and is slidably guided by it. The inner housing 60 has an elongated shaft portion 61 and a protrusion 76 protruding from the shaft portion 61. The distal end of the protrusion 76 has a rocker arm interface 77 that directly engages the rocker arm 12. The protrusion 76 and the shaft portion 61 define a stepped ring interface 78. At least a portion of the protrusion 76 extends to the outside of the bore 52 of the outer housing 42. The inner housing 60 can be locked and unlocked from the outer housing 42 via a first locking bolt 66A and a second locking bolt 66B, each of which engages a corresponding first locking aperture 49A and a second locking aperture 49B of the outer housing 42. Only one locking bolt can be used instead of two. The first locking bolt 66A and the second locking bolt 66B can be a pin, a plate, a ball or any suitable shape for locking the inner housing 60 to the outer housing 42. Furthermore, the first and second locking pegs 66A, 66B may include curved surfaces, flat surfaces, angled surfaces, or any suitable surfaces for locking the inner housing 60 to the outer housing 42 .

[0037] The first locking bolt 66A and the second locking bolt 66B are arranged in a common locking hole 62, which extends through the locking end 63 of the shaft portion 61. Each of the first locking bolt 66A and the second locking bolt 66B can also be arranged in a separate non-connecting hole. The return spring 68 is arranged in the locking hole 62 between the first locking bolt 66A and the second locking bolt 66B so that the first locking bolt 66 and the second locking bolt 66B are preloaded against the locking bolt retaining ring 90 used as an external stop. The locking bolt retaining ring 90 installed in the groove 64 of the inner housing 60 engages the first flat surface 67A of the first locking bolt 66A and the second flat surface 67B of the second locking bolt 66 to also prevent the first locking bolt 66A and the second locking bolt 66B from rotating around the axis A3 of the locking hole 62.

[0038] The switchable valve bridge 40 includes a locking collar 70 which is slidably guided by the outer surface 56 of the extension 48 of the outer housing 42. The locking collar 70 includes a flange 74 and a sleeve 72. The flange 74 has an arm platform 75 ( Figure 2 ), the arm platform 75 is configured to receive the first finger 31A and the second finger 31B of the arm 28; the first finger 31A and the second finger 31B engage the arm platform 75 at positions 180 degrees apart. The sleeve 72 includes an inner radial surface 73 surrounding and accommodating the first ramp 80A and the second ramp 80B and the upper portion of the ramp return spring 86.

[0039] exist Fig.13AIn the first locking position of the switchable valve bridge 40 shown, the first locking bolt 66A and the second locking bolt 66B protrude radially outward from the radial outer surface 65 of the shaft portion 61 of the inner housing 60 so that the first end 69A of the respective first locking bolt 66A and the second end 69B of the respective second locking bolt 66B engage the first locking surface 54A of the respective first locking aperture 49A and the second locking surface 54B of the respective second locking aperture 49B. In the first locking position, the actuator pin 22 of the actuator 20 is in the retracted position and the arm 28 is forced upward in the second direction D2 via the arm return spring 24 mounted on the bracket 26 and the ramp return spring 86 engaging the first ramp 80A and the second ramp 80B. In this upward position of the arm 28, the locking collar 70 is pushed upward via the ramp return spring 86 until it abuts against the circlip 92 in the groove 50 mounted on the extension 48 of the outer housing 42. When in the first locked position, the rotational movement of the camshaft 10 is converted into a linear valve lift of the poppet valve 16 via the rocker arm 12 and the switchable valve bridge 40. That is, the rotation of the camshaft 10 causes the rocker arm 12 to pivot about the rocker arm axis A1, so that the rocker arm 12 pushes the poppet valve 16 downward in the first direction D1, so that the poppet valve 16 moves or opens in the first direction D1. In the first locked position, the inner housing 60 is locked to the outer housing 42, so that all rotational movements of the camshaft 10 are converted into linear movements of the poppet valve 16 via the rocker arm 12 and the switchable valve bridge 40.

[0040] exist Fig. 13BIn the second unlocked position of the switchable valve bridge 40 shown, the first locking bolt 66A and the second locking bolt 66B are pushed or moved radially inward by the corresponding first ramp 80A and the second ramp 80B to unlock the inner housing 60 from the outer housing 42. The actuator pin 22 of the actuator 20 engages with the first end 29 of the arm 28 so that the actuation force F1 applied to the arm 28 by the actuator pin 22 causes the arm 28 to move downward in the first direction D1. The second end 30 of the arm 28 is defined by the first finger 31A and the second finger 31B. The arm 28 can be described as having a second end 30 divided into two fingers. The first finger 31A and the second finger 31B engage opposite sides of the locking collar 70 of the switchable valve bridge 40. Therefore, when the arm 28 is pushed downward in the first direction via the actuation force F1, the actuation force F1 is transmitted to the locking collar 70 of the switchable valve bridge 40. The actuation force F1 overcomes: i) the force F2 applied to the locking collar 70 by the ramp return spring 86 (via the first ramp 80A and the second ramp 80B), and ii) the force F3 applied to the arm 28 by the arm return spring 24 mounted on the bracket 26, so that the locking collar 70 moves downward in the first direction D1. As described herein and shown in the figures, the actuation force F1 does not come from pressurized hydraulic fluid. Instead, the actuation force F1 comes from the actuation force of an electromechanical device or electromechanical actuator. In other exemplary embodiments, the locking collar 70 can be hydraulically displaced.

[0041] To change or transition the switchable valve bridge 40 from the second unlocked position to the first locked position, the actuator pin 22 of the actuator 20 is electrically retracted so that the arm 28 moves upward (in the second direction D2) by the force F3 exerted on the arm 28 by the arm return spring 24 ( Figure 1 ); the locking collar 70 and the first ramp 80A and the second ramp 80B move upward by the force F2 provided by the ramp return spring 86 ( Fig.13A ). The lower end of the ramp return spring 86 engages the top of the spring collar 94, and the upper end of the ramp return spring 86 engages the first bottom annular surface 88A of the first ramp 80A and the second bottom annular surface 88B of the second ramp 80B, respectively. The spring collar 94 and the lower end 58 of the extension 48 of the outer housing 42 can engage the cylinder head (not shown). In other exemplary embodiments, the spring collar 94 can be eliminated and the spring can directly abut the cylinder head or abut the radially exposed portion of the extension 48 of the outer housing 42.

[0042] like Fig. 10A , Fig. 10B and Fig. 13BAs shown, the first ramp 80A and the second ramp 80B are two independent parts received in the radially inwardly protruding step 71 of the locking collar 70. The first ramp 80A and the second ramp 80B have corresponding first arc-shaped bodies 82A and second arc-shaped bodies 82B, respectively, and the first arc-shaped bodies 82A and the second arc-shaped bodies 82B have first top annular surfaces 81A and second top annular surfaces 81B, first bottom annular surfaces 88A and second bottom annular surfaces 88B, and first protrusions 87A and second protrusions 87B, respectively. The first protrusions 87A and the second protrusions 87B protrude radially inward from the corresponding curved inner side portions 83A and 83B of the arc-shaped bodies 82A and 82B. Fig.13A and Fig. 13B As can be clearly seen in the figure, the first ramp 80A and the second ramp 80B are mounted on the extension 48 of the outer shell 42 so that the first protrusion 87A and the second protrusion 87B extend or are continuously disposed in the corresponding first locking aperture 49A and the second locking aperture 49B throughout the first locked position and the second unlocked position. The first protrusion 87A and the second protrusion 87B respectively have a first tapered bolt interface 84A and a second tapered bolt interface 84B that tapers at an angle An1. The first tapered bolt interface 84A and the second tapered bolt interface 84B can be radially inclined inward as they extend along the second direction D2; alternatively, the first tapered bolt interface 84A and the second tapered bolt interface 84B can be radially reduced as they extend along the second direction D2. The movement of the first ramp 80A and the second ramp 80B in the first direction D1 via the locking collar 70 causes the first tapered bolt interface 84A and the second tapered bolt interface 84B to engage the corresponding first outer ends 69A and second outer ends 69B of the first locking bolt 66A and the second locking bolt 66B. Due to the "radially reduced" form of the first tapered bolt interface 84A and the second tapered bolt interface 84B described above, further downward movement of the first ramp 80A and the second ramp 80B causes the first locking bolt 66A and the second locking bolt 66B to move radially inward within the locking hole 62 to unlock the inner housing 60 from the outer housing 42. The first outer end 69A and the second outer end 69B of the first locking bolt 66A and the second locking bolt 66B can be curved, such as Figure 13A-13B As shown, any other suitable shape that interfaces with the first slope 80A and the second slope 80B may also be used.

[0043] As previously described, the first and second projections 87A, 87B are continuously disposed within the respective first and second locking apertures 49A, 49B throughout the first locked and second unlocked positions. Fig.13AIn the first locked position shown, the first protrusion 87A and the second protrusion 87B are located at the upper part of the first locking aperture 49A and the second locking aperture 49B, respectively. During the transition from the first locked position to the second unlocked position, the first protrusion 87A and the second protrusion 87B move downwardly in the first direction D1 within the corresponding first locking aperture 49A and the second locking aperture 49B. Once the first ramp 80A and the second ramp 80B (via the locking collar 70) reach the second locked position, the first protrusion 87A and the second protrusion 87B are located at the lower part of the corresponding first locking aperture 49A and the second locking aperture 49B, as shown in FIG. Fig. 13B shown.

[0044] The lost motion spring 32 is axially disposed between the inner housing 60 and the end of the hole 52 of the outer housing 42. It can be said that the inner housing 60 and the lost motion spring are disposed in series within the hole 52. Fig.13A , the lost motion spring 32 applies a force F3 to the lower side of the inner housing 60, so that the stepped ring interface 78 on the inner housing 60 is forcibly engaged with the mechanical clearance adjustment ring 36, and the mechanical clearance adjustment ring 36 is retained in the hole 52 of the outer housing 42 by the inner housing retaining ring 34. When the switchable valve bridge 40 is in the second unlocked position, the rotational movement of the camshaft 10 is converted into a linear movement of the inner housing 60 in the hole 52 of the outer housing 42. Therefore, when the camshaft 10 rotates, the inner housing 60 reciprocates up and down in the hole 52 along the actuation axis A2 of the inner housing with the help of the lost motion spring 32, and the lost motion spring 32 provides a return device for the inner housing 60 to return it to the uppermost position in the hole. The actuation axis A2 is parallel to the first direction D1 and the second direction D2.

[0045] Go to Figure 3 , the mechanical clearance adjustment ring 36 is selectively mounted on the clearance step 45 of the bore 52 of the outer housing 42. The mechanical clearance adjustment ring 36 is selected from a plurality of clearance adjustment ring groups, which are classified according to their thickness T. The mechanical clearance adjustment ring 36 (and its corresponding thickness) controls the axial position of the inner housing 60 within the bore 52, or more precisely, controls the mechanical clearance L1 or gap between the first and second locking bolts 66A and 66B and the corresponding first and second locking apertures 54A and 54B, as shown in FIG. Fig.13A As shown. The mechanical clearance L1 and its tolerance are design parameters of the switchable valve bridge 40 that may be specified by the internal combustion engine manufacturer. In an exemplary embodiment, the mechanical clearance L1 is less than one millimeter. As known in the art, the mechanical clearance L1 may correspond to an opening slope of the camshaft lobe, such that the opening slope is configured to cause the first locking bolt 66A and the second locking bolt 66B to gently abut against the corresponding first locking aperture 54A and the second locking aperture 54B of the outer housing 42 to avoid severe impact and resulting wear at the interface.

[0046] In an example embodiment of the assembly process, a mechanical lash adjustment ring 36 ("gauge ring") having a known thickness may be installed with the inner housing retaining ring 34 snapped into the retaining groove 43. The mechanical lash of the switchable valve bridge 40 may then be measured; based on the lash measurement, an appropriate mechanical lash adjustment ring 36 (based on its thickness T) may be selected to achieve a mechanical lash that falls within a predetermined mechanical lash design range for the switchable valve bridge 40. The thickness of the selected mechanical lash adjustment ring 36 may be equal to, less than, or greater than the thickness of the gauge ring.

[0047] Other suitable mechanical lash adjusters 38 than those previously described and shown in the figures may also be applied to the switchable valve bridge 40 .

[0048] In the example embodiment described previously, when the switchable valve bridge 40 is in the second unlocked position, the inner housing 60 is slidably moved downward in the first direction D1 within the bore 52 of the outer housing 42. This can be described as a telescoping action of the inner housing 60 relative to the outer housing 42. The magnitude of the displacement of the inner housing 60 relative to the outer housing 42 is generally referred to as an idle stroke. During the first locked position of the switchable valve bridge 40, the magnitude of the idle stroke may be at least as large as the valve lift of the poppet valve 16. In this case, the second unlocked position will produce a no-valve-lift or zero-valve-lift state of the poppet valve 16, which is generally referred to as valve deactivation.

[0049] In another example embodiment, the idle stroke can be less than the valve lift of the poppet valve 16 present during the first locked position, so that the poppet valve 16 can have a small amount of valve lift when it is in the second unlocked position. Therefore, the switchable valve bridge 40 can facilitate two different non-zero valve lift opening amplitudes depending on the corresponding first locked position and second unlocked position. For example, the first locked position can produce a full or standard valve lift of the poppet valve 16 (as in the previous valve disable example), and the second unlocked position can produce a partial valve lift greater than zero but less than full valve lift. This can be achieved by limiting the idle stroke of the inner housing 60 by incorporating an end stop for the inner housing 60 into the hole 52 of the outer housing 42. Other suitable devices for limiting the idle stroke are also possible. Unlike conventional cam profile switching valve mechanism systems, the two different non-zero valve lifts achieved by the first locked position and the second unlocked position can be achieved with a single camshaft lobe.

[0050] Although exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms covered by the claims. The words used in the specification are descriptive rather than limiting, and it should be understood that various changes can be made without departing from the spirit and scope of the invention. As previously mentioned, the features of the various embodiments can be combined to form further embodiments of the present invention, which may not be explicitly described or explained. Although various embodiments may have been described as providing advantages or superiority over other embodiments or prior art embodiments with respect to one or more desired characteristics, a person of ordinary skill in the art knows that one or more features or characteristics can be compromised to achieve the desired overall system properties, depending on the specific application and implementation. Therefore, with respect to one or more characteristics, to the extent that any embodiment is described as less desirable than other embodiments or prior art embodiments, these embodiments are not outside the scope of the present invention and may be desirable for a particular application.

Claims

1. A switchable valve bridge for an internal combustion engine, the switchable valve bridge comprising: An outer shell having: a first valve carrier plate configured to engage with the first poppet valve; a second valve carrier plate configured to engage with a second poppet valve; and a first locking aperture; an inner housing slidably disposed within the outer housing, the inner housing having a first locking bolt configured to move radially relative to an actuation axis of the inner housing; a locking collar configured to be axially moved in a first axial direction via an actuation force applied to the locking collar; a first ramp disposed within the first locking aperture and configured to be actuated by the locking collar such that axial movement of the first ramp causes radial movement of the first locking bolt, the first ramp being configured to directly engage the first locking bolt; and a first locked position, wherein the first locking bolt engages the first locking aperture such that the inner housing is locked to the outer housing; and A second unlocked position, wherein the first locking bolt is in a radially inward position such that the inner housing is unlocked from the outer housing.

2. The switchable valve bridge according to claim 1, wherein: The first ramp includes a tapered interface configured to engage the first locking bolt.

3. The switchable valve bridge according to claim 2, wherein: The tapered interface engages a curved surface of the first locking bolt. 4 . The switchable valve bridge of claim 1 , further comprising a mechanical lash adjustment ring disposed between the inner housing and the outer housing, the mechanical lash adjustment ring being configured to be selectively installed to adjust an axial position of the inner housing relative to the outer housing. 5 . The switchable valve bridge of claim 1 , further comprising a return spring configured to move the locking collar in a second axial direction when the actuation force is less than a force of the return spring. 6 . The switchable valve bridge of claim 1 , further comprising a lost motion spring disposed between the inner housing and the outer housing.

7. The switchable valve bridge according to claim 6, wherein: The outer housing is configured with a bore extending along the actuation axis, and the inner housing and the lost motion spring are arranged in series within the bore.

8. The switchable valve bridge according to claim 7, wherein: The inner housing includes a protrusion that protrudes out of the aperture of the outer housing, and the protrusion includes a rocker arm interface configured to directly engage a rocker arm.

9. The switchable valve bridge according to claim 1, wherein: The first ramp is disposed within the locking collar.

10. The switchable valve bridge according to claim 1, further comprising: a second locking aperture disposed on the outer housing; a second locking bolt configured to engage the second locking aperture in the first locking position; and A second ramp is disposed within the second locking aperture, the second ramp being configured to: i) directly engage the second locking bolt, and ii) be actuated by the locking collar.

11. The switchable valve bridge according to claim 10, wherein: The first ramp and the second ramp are independent components.

12. The switchable valve bridge according to claim 1, wherein: The actuation force does not come from pressurized hydraulic fluid.

13. A switchable valve bridge for an internal combustion engine, the switchable valve bridge comprising: an outer housing configured to actuate two poppet valves, the outer housing having an extension including a locking aperture; an inner housing slidably disposed within the bore of the extension, the inner housing having a locking bolt configured to move radially relative to an actuation axis of the inner housing; a locking collar configured to: i) be axially moved in a first direction via an actuation force applied to the locking collar, and ii) be slidably guided by an outer surface of the extension; and a ramp disposed within the locking collar and the locking aperture, the ramp being configured to be actuated by the locking collar such that axial movement of the ramp within the locking aperture causes radial movement of the locking bolt from a first locked position in which the locking bolt engages the locking aperture to a second unlocked position in which the inner housing is unlocked from the outer housing.

14. The switchable valve bridge according to claim 13, further comprising a clearance adjustment ring arranged in the hole, the clearance adjustment ring being selected from one of a plurality of clearance adjustment ring groups to achieve a predetermined mechanical clearance between the inner housing and the outer housing, the plurality of clearance adjustment ring groups being classified according to thickness.

15. The switchable valve bridge according to claim 13, wherein: The locking bolt includes a flat surface configured to engage a flat surface of the locking aperture in the first locked position.

16. The switchable valve bridge of claim 13, further comprising a lost motion spring disposed within the bore of the extension.

17. The switchable valve bridge of claim 16, further comprising a return spring arranged to engage at least one of the ramp or the locking collar, the return spring being configured to move the ramp and the locking collar in a second axial direction when the actuation force is less than the force of the return spring.

18. A switchable valve bridge system for an internal combustion engine, the switchable valve bridge system comprising: Electric actuator; an arm configured to be actuated by the electric actuator; Switchable valve bridge, including: an outer housing configured to actuate two poppet valves, the outer housing having an extension including a locking aperture; an inner housing slidably disposed within the bore of the outer housing, the inner housing having a locking bolt configured to move radially relative to an actuation axis of the inner housing; a locking collar engaged with the arm and configured to be axially moved via an actuation force from the arm via the electric actuator; and a ramp disposed within the locking collar, the ramp being configured to be actuated by the locking collar such that axial movement of the ramp causes radial movement of the locking bolt from a first locked position in which the locking bolt engages the locking aperture to a second unlocked position in which the inner housing is unlocked from the outer housing.

19. The switchable valve bridge system according to claim 18, wherein: The arm includes two fingers that extend on opposite sides of the outer housing and engage the locking collar.

20. The switchable valve bridge system of claim 18, further comprising a mechanical lash adjuster configured to adjust an axial position of the inner housing within the bore to selectively adjust a mechanical lash between the inner housing and the outer housing.

Images