ROCKER SHAFT WITH DE-AERATION OIL GALLERY SEGMENT
20170284236 · 2017-10-05
Assignee
Inventors
- Faheem AHMED (Troy, MI, US)
- Colin FOSTER (Belle River, CA)
- David CHANDLER (Windsor, CA)
- John WHITTON (Milwaukee, WI, US)
- Debora MANTHER (Royal Oak, MI, US)
- Pradeep Mohan MOHAN DAS (Troy, MI, US)
- Sumukha NAGARAJ (Dearborn, MI, US)
Cpc classification
F01L1/181
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L1/46
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01M9/107
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L2001/186
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L2305/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L13/0005
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01M9/105
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L1/18
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L1/24
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L1/053
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02F7/0068
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01L1/2416
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
Abstract
A switchable valve train assembly including a carrier housing defining a hydraulic circuit, a supply assembly, a plurality of rocker shafts, a plurality of separators, and a plurality of rocker arm assemblies is provided. Each one of the plurality of separators divides the rocker shafts into (1) a first chamber extending between a first chamber axial end and the separator, and (2) a second chamber extending between a second chamber axial end and the separator. The plurality of separators each include an orifice defined between the first chamber and the second chamber that provides fluid connection between the first chamber and the second chamber. Locking assemblies of the rocker arm assemblies are selectively actuated based on the supply assembly. The separators ensure that hydraulic fluid within the hydraulic fluid is de-aerated and that the second chambers remain primed with hydraulic fluid for faster actuation of the locking assemblies.
Claims
1. A switchable valve train assembly comprising: a carrier housing defining a hydraulic circuit, the carrier housing including rocker shaft support regions and a supply assembly support region; a supply assembly connected to the supply assembly support region of the carrier housing including a pressurized fluid source for providing pressurized hydraulic fluid to the hydraulic circuit, and a solenoid and a control valve for selectively supplying the pressurized hydraulic fluid to the hydraulic circuit; a hydraulic lash adjuster feed channel defined by the hydraulic circuit in fluid connection with the pressurized fluid source; a switch channel defined by the hydraulic circuit in fluid connection with the control valve; a plurality of rocker shafts supported on the rocker shaft support regions of the carrier housing, each one of the plurality of rocker shafts including a central space with one or more chambers defined by a radially inner surface; a plurality of separators each secured in the central space of a respective one of the plurality of rocker shafts, and a radially outer surface of each one of the plurality of separators engages the radially inner surface of a respective one of the plurality of rocker shafts, each one of the plurality of separators divides the central space of the each one of the rocker shafts into (1) a first chamber extending between a first chamber axial end and the separator, and (2) a second chamber extending between a second chamber axial end and the separator, the plurality of separators each include an orifice defined between the first chamber and the second chamber providing fluid connection between the first chamber and the second chamber, wherein the hydraulic lash adjuster feed channel is in fluid communication with the first chambers of each one of the plurality of rocker shafts via the hydraulic circuit; wherein the switch channel is in fluid communication with the second chambers of each one of the plurality of rocker shafts via the hydraulic circuit; and a plurality of rocker arm assemblies each arranged on a respective one of the plurality of rocker shafts, each one of the plurality of rocker arm assemblies includes a hydraulic lash adjuster connected to a first intake port and a locking assembly connected to a second intake port, the first chamber of each one of the plurality of rocker shafts includes a first actuator port in fluid connection with a respective one of the first intake ports for the hydraulic lash adjuster, and the second chamber of each one of the plurality of rocker shafts includes a second actuator port in fluid connection with a respective one of the second intake ports for the locking assembly.
2. The switchable valve train assembly of claim 1, wherein a first pair of the plurality of the rocker shafts are arranged in series and axially spaced apart from each other, and a second pair of the plurality of rocker shafts are arranged in series and axially spaced apart from each other.
3. The switchable valve train assembly of claim 1, wherein the rocker shaft support regions of the carrier housing are each configured to support at least two rocker shafts.
4. The switchable valve train assembly of claim 1, wherein the plurality of rocker shafts includes four rocker shafts, the plurality of rocker arm assemblies includes four switchable rocker arm assemblies and four standard rocker arm assemblies, and the plurality of separators includes four separators.
5. The switchable valve train assembly of claim 1, wherein the carrier housing is formed from aluminum.
6. The switchable valve train assembly of claim 1, wherein galleries of the hydraulic circuit of the carrier housing are formed by drilling.
7. The switchable valve train assembly of claim 6, wherein axial ends of the hydraulic circuit are defined by caps pressed into the carrier housing.
8. The switchable valve train assembly of claim 1, wherein the plurality of separators are press-fit within a respective one of the plurality of rocker shafts.
9. The switchable valve train assembly of claim 1, wherein (1) the supply assembly has a first state in which the control valve closes a flow path from the pressurized fluid source to the switch channel, and the orifices of the plurality of separators allow pressurized hydraulic fluid to flow from the first chambers to the second chambers in each one of the plurality of rocker shafts, and the second chambers direct pressurized hydraulic fluid to the switch channel, and (2) the supply assembly has a second state in which the solenoid is activated and the control valve opens the flow path from the pressurized fluid source to the switch channel such that pressurized hydraulic fluid is provided via the switch channel to the locking assemblies of each one of the plurality of rocker arm assemblies via the second chambers.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The foregoing Summary and the following detailed description will be better understood when read in conjunction with the appended drawings, which illustrate a preferred embodiment of the invention. In the drawings:
[0012]
[0013]
[0014]
[0015]
[0016]
[0017]
[0018]
[0019]
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Certain terminology is used in the following description for convenience only and is not limiting. The words “front,” “rear,” “upper” and “lower” designate directions in the drawings to which reference is made. The words “inwardly” and “outwardly” refer to directions toward and away from the parts referenced in the drawings. “Axially” refers to a direction along the axis of a shaft. A reference to a list of items that are cited as “at least one of a, b, or c” (where a, b, and c represent the items being listed) means any single one of the items a, b, or c, or combinations thereof. The terminology includes the words specifically noted above, derivatives thereof and words of similar import.
[0021] Referring to
[0022] The rocker shaft 30 includes a central opening 33 defined by a radially inner surface 31. The rocker shaft 30 can be formed from steel, aluminum, or any other suitable material. A separator 48 is secured in the central opening 33 of the rocker shaft 30 and a radially outer surface 51 of the separator 48 engages the radially inner surface 31 of the rocker shaft 30. In one embodiment, the separator 48 is press-fit within the rocker shaft 30. The separator 48 divides the central opening 33 of the rocker shaft 30 into (1) a first chamber 32 extending between a first chamber axial end 34 of the rocker shaft 30 and the separator 48, and (2) a second chamber 38 extending between a second chamber axial end 36 of the rocker shaft 30 and the separator 48. The separator 48 includes an orifice 50 defined between the first chamber 32 and the second chamber 38 providing fluid connection between the first chamber 32 and the second chamber 38. The separator 48 can be formed from plastic, metal, or any other suitable material. One of ordinary skill in the art would recognize from the present disclosure that the shape of the separator 48 can be varied. Any shape or configuration of the separator 48 can be used as long as the separator 48 provides three main functions: (1) dividing the rocker shaft 30 into the first chamber 32 and the second chamber 38; (2) directing pressurized hydraulic fluid out of the first chamber 32 and the second chamber 38 and towards a rocker arm assembly 60; and (3) providing fluid connection between the first chamber 32 and the second chamber 38, i.e. via the orifice 50.
[0023] A first chamber end cap 40 fixed in the rocker shaft 30 defines the first chamber axial end 34, and a second chamber end cap 42 fixed in the rocker shaft 30 defines the second chamber axial end 36. The hydraulic lash adjuster feed channel 22 is in fluid communication with the first chamber 32 and the switch channel 26 is in fluid communication with the second chamber 38. The orifice 50 reduces air pockets and air bubbles in the second chamber 38 in order to improve the function of the switchable valve train assembly 10. The orifice 50 ensures that the second chamber 38 is always filled with hydraulic fluid and immediately available for a switching operation which reduces switching times of the switchable valve train assembly 10.
[0024] A first tube 44 extends between the hydraulic lash adjuster feed channel 22 and the first chamber 32. A second tube 46 extends between the switch channel 26 and the second chamber 38. One of ordinary skill in the art would recognize from the present disclosure that alternative channeling arrangements could be used to direct pressurized hydraulic fluid from the supply assembly 12 to the rocker shaft 30 which do not include separately formed sleeves 44, 46.
[0025] The rocker arm assembly 60 is arranged on the rocker shaft 30 and includes a hydraulic lash adjuster 70 connected to a first intake port 74 and a locking assembly 80 connected to a second intake port 78. The first chamber 32 includes a first actuator port 72 in fluid connection with the first intake port 74 for the hydraulic lash adjuster 70, and the second chamber 38 includes a second actuator port 76 in fluid connection with the second intake port 78 for the locking assembly 80. The hydraulic lash adjuster 70 and the locking assembly 80 are selectively operated based on the supply of pressurized hydraulic fluid from the supply assembly 12. In one embodiment, the separator 48 includes a first recess 53 on the radially outer surface 51 that defines a first passage 57 between the first chamber 32 and the first actuator port 72, and the separator 48 includes a second recess 55 on the radially outer surface 51 that defines a second passage 59 between the second chamber 38 and the second actuator port 76. As shown in
[0026] In one embodiment, the rocker shaft 30 includes a first axially extending flange 56 at the first chamber axial end 34 and a second axially extending flange 58 at the second chamber axial end 36. A first bolt 62 radially extends through the first axially extending flange 56 and a second bolt 64 radially extends through the second axially extending flange 58. In one embodiment, the first chamber end cap 40 is fixed to the first chamber axial end 34 of the rocker shaft 30 via a press-fit against a radially inner surface 66 of the first axially extending flange 56. The second chamber end cap 42 is also fixed to the second chamber axial end 36 of the rocker shaft 30 via a press-fit against a radially inner surface 68 of the second axially extending flange 58. One of ordinary skill in the art would recognize from the present disclosure that alternative configurations of the end portions of the rocker shaft 30 may be used.
[0027] As shown in
[0028] As shown in
[0029]
[0030] Referring to
[0031] Referring to
[0032] The embodiments shown in
[0033]
[0034]
[0035] Rocker arm assemblies 560A, 560B, 560C, 560D (shown in broken lines in
[0036] A pressurized fluid source 514A is provided at a first end of rocker shafts 530A, 530B. In one embodiment, the pressurized fluid source 514A is provided in two journals. The pressurized fluid source 514A feeds pressurized hydraulic fluid into feed channels 515A, 515B which channel pressurized hydraulic fluid directly into the first chambers 532A, 532B of rocker shafts 530A, 530B. Another feed channel 515C extends beyond the rocker shafts 530A, 530B to provide pressurized hydraulic fluid from the pressurized fluid source 514A to rocker shaft 530C, and rocker shaft 530D via feed channel 515D. Supply assembly 512 provides a tank connection via tank channels 512A, 512B, and a pressurized fluid supply channel 514B. The supply assembly 512 is identical to the supply assembly 12 described in detail above. Switching channels 526A, 526B, 526C, 526D provide a fluid connection from a respective one of the second chambers 538A, 538B, 538C, 538D to the supply assembly 512.
[0037]
[0038]
[0039] As shown in
[0040] As described above with respect to
[0041] Having thus described the present invention in detail, it is to be appreciated and will be apparent to those skilled in the art that many physical changes, only a few of which are exemplified in the detailed description of the invention, could be made without altering the inventive concepts and principles embodied therein. It is also to be appreciated that numerous embodiments incorporating only part of the preferred embodiment are possible which do not alter, with respect to those parts, the inventive concepts and principles embodied therein. The present embodiment and optional configurations are therefore to be considered in all respects as exemplary and/or illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all alternate embodiments and changes to this embodiment which come within the meaning and range of equivalency of said claims are therefore to be embraced therein.
LIST OF REFERENCES
[0042] switchable valve train assembly 10
[0043] supply assembly 12
[0044] check valve 13
[0045] pressurized fluid source 14A, 14B
[0046] solenoid 16
[0047] control valve 18
[0048] hydraulic lash adjuster feed channel 22
[0049] switch channel 26
[0050] rocker shaft 30
[0051] radially inner surface 31
[0052] first chamber 32
[0053] central opening 33
[0054] first chamber axial end 34
[0055] second chamber axial end 36
[0056] second chamber 38
[0057] first chamber end cap 40
[0058] second chamber end cap 42
[0059] first sleeve 44
[0060] second sleeve 46
[0061] separator 48
[0062] orifice 50
[0063] radially outer surface 51
[0064] first recess 53
[0065] second recess 55
[0066] first axially extending flange 56
[0067] first passage 57
[0068] second axially extending flange 58
[0069] second passage 59
[0070] rocker arm assembly 60
[0071] first bolt 62
[0072] second bolt 64
[0073] radially inner surface 66
[0074] radially inner surface 68
[0075] hydraulic lash adjuster 70
[0076] first actuator port 72
[0077] first intake port 74
[0078] second actuator port 76
[0079] second intake port 78
[0080] locking assembly 80
[0081] switchable valve train assembly 100
[0082] rocker shaft 101
[0083] hollow center 104
[0084] camshaft end 106
[0085] valve end 108
[0086] plurality of rocker arm assemblies 110
[0087] carrier housing 500
[0088] supply assembly support region 502
[0089] rocker shaft support regions 504A, 504B
[0090] switchable valve train assembly 510
[0091] tank channels 512A, 512B
[0092] pressurized fluid source 514A
[0093] feed channels 515A, 515B, 515C, 515D
[0094] switching channels 526A, 526B, 526C, 526D
[0095] rocker shafts 530A, 530B, 530C, 530D
[0096] first chambers 532A, 532B, 532C, 532D
[0097] second chambers 538A, 538B, 538C, 538D
[0098] separators 548A, 548B, 548C, 548D
[0099] switchable rocker arm assemblies 560A, 560B, 560C, 560D
[0100] standard rocker arm assemblies 561A, 561B, 561C, 561D