Patent Application
20180266284
The present disclosure relates to an oil reservoir for a variable camshaft phaser, in particular, a locking cover with a recess for minimizing the total required axial space of the oil reservoir.
A variable camshaft phaser (VCP) is an internal combustion engine component that controls the timing of the valve lift event. The combustion process can be improved when the engine timing is properly varied. The benefits from properly varied engine timing include increased engine efficiency, improved idle stability, torque/potency enhancement, increased fuel economy, and reduced hydrocarbon emissions. Hydraulic VCPs operate utilizing oil pressure (in a closed chamber) and torsionals (kinetic energy) provided by the cams. In general, VCPs comprise a driven element, covers, and a driver element, which is connected to the camshaft in some way. An oil control valve (OCV) is used to control the oil flow supplied by the engine oil pump, via the main oil reservoir, to the VCP inner chambers. When the VCP is full and the proper pressure is established inside, the driver element (i.e., rotor) rotates. This is called camshaft phasing.
According to aspects illustrated herein, there is provided an oil reservoir for a variable camshaft phaser, comprising a locking cover, including a front surface including a pool, the pool having a plurality of through-bores, a rear surface including a locking pin channel, a radially inward facing surface, and a radially outward facing surface, and an oil reservoir cover secured to the front surface of the locking cover.
According to aspects illustrated herein, there is provided an oil reservoir for a variable camshaft phaser, comprising a locking cover, including a front surface including a pool, the pool having a plurality of through-bores, a rear surface including a locking pin channel, a radially inward facing surface including a recess extending radially outward therefrom, and a radially outward facing surface, and an oil reservoir cover secured to the front surface of the locking cover.
According to aspects illustrated herein, there is provided an oil reservoir for a variable camshaft phaser, comprising a locking cover, including a front surface including a pool having a plurality of through-bores, a first plurality of holes operatively arranged to attach the locking cover to the variable camshaft phaser using a plurality of bolts, a rear surface including a locking pin channel, a radially inward facing surface including a recess extending radially outward therefrom, and a radially outward facing surface, and an oil reservoir cover secured to the front surface of the locking cover.
It therefore is an object of the disclosure to provide an oil reservoir requiring minimal axial space.
These and other objects, features, and advantages of the present disclosure will become readily apparent upon a review of the following detailed description of the disclosure, in view of the drawings and appended claims.
Various embodiments are disclosed, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, in which:
At the outset, it should be appreciated that like drawing numbers on different drawing views identify identical, or functionally similar, structural elements. It is to be understood that the claims are not limited to the disclosed aspects.
Furthermore, it is understood that this disclosure is not limited to the particular methodology, materials and modifications described and as such may, of course, vary. It is also understood that the terminology used herein is for the purpose of describing particular aspects only, and is not intended to limit the scope of the claims.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this disclosure pertains. It should be understood that any methods, devices or materials similar or equivalent to those described herein can be used in the practice or testing of the example embodiments. The assembly of the present disclosure could be driven by hydraulics, electronics, and/or pneumatics.
It should be appreciated that the term “substantially” is synonymous with terms such as “nearly,” “very nearly,” “about,” “approximately,” “around,” “bordering on,” “close to,” “essentially,” “in the neighborhood of,” “in the vicinity of,” etc., and such terms may be used interchangeably as appearing in the specification and claims. It should be appreciated that the term “proximate” is synonymous with terms such as “nearby,” “close,” “adjacent,” “neighboring,” “immediate,” “adjoining,” etc., and such terms may be used interchangeably as appearing in the specification and claims. The term “approximately” is intended to mean values within ten percent of the specified value.
By “non-rotatably connected” elements, we mean that: the elements are connected so that whenever one of the elements rotate, all the elements rotate; and relative rotation between the elements is not possible. Radial and/or axial movement of non-rotatably connected elements with respect to each other is possible, but not required.
Adverting now to the figures,
To clarify the spatial terminology, objects 12, 13, and 14 are used. An axial surface, such as surface 15 of object 12, is formed by a plane co-planar with axis 11. Axis 11 passes through planar surface 15; however any planar surface co-planar with axis 11 is an axial surface. A radial surface, such as surface 16 of object 13, is formed by a plane orthogonal to axis 11 and co-planar with a radius, for example, radius 17. Radius 17 passes through planar surface 16; however any planar surface co-planar with radius 17 is a radial surface. Surface 18 of object 14 forms a circumferential, or cylindrical, surface. For example, circumference 19 passes through surface 18. As a further example, axial movement is parallel to axis 11, radial movement is orthogonal to axis 11, and circumferential movement is parallel to circumference 19. Rotational movement is with respect to axis 11. The adverbs “axially,” “radially,” and “circumferentially” refer to orientations parallel to axis 11, radius 17, and circumference 19, respectively. For example, an axially disposed surface or edge extends in direction AD, a radially disposed surface or edge extends in direction R, and a circumferentially disposed surface or edge extends in direction CD.
Depressions 85 are sunken areas in front surface 82a arranged circumferentially thereon and proximate radially outward facing edge 84. Cover bolts holes 88 are arranged in each of depressions 85. Depressions 85 are operatively arranged to align and engage with counter-bores 66. Cover bolts holes 88 are operatively arranged to align with cover bolts holes 64. In an example embodiment, as shown in
Camshaft phaser locking cover 20 is a circular plate comprising center through-bore 22, radially outward facing surface 30, radially inward facing surface 40, rear surface 50, and front surface 60. For the purposes of this description, locking cover 20 is arranged concentrically about axis of rotation 24.
Radially outward facing surface 30 and radially inward facing surface 40 are circumferential surfaces extending axially from front surface 60 to rear surface 50. Radially inward facing surface 40 comprises recess 42 arranged circumferentially thereon. Recess 42 extends radially outward in direction RIM from radially inward facing surface 40. Recess 42 is designed to allow oil to drain from variable camshaft phaser 100, specifically the rotor, so that the locking pin is not prevented from disengaging locking pin channel 52 of cover plate 20. Oil can drain from the locking pin hole (in the rotor), out of variable camshaft phaser 100 through recess 42, and into oil reservoir 90. In an example embodiment, recess 42 comprises surface 44, surface 46, and surface 48 (shown in
Rear surface 50 is a substantially planar radial surface directed toward variable camshaft phaser 100 during assembly. Rear surface 50 comprises locking pin channel 52. Locking pin channel 52 is a groove in rear surface 50 operatively arranged to receive the locking pin of variable camshaft phaser 100. When locking cover 20 is secured to variable camshaft phaser 100, locking pin channel 52 aligns with the locking pin hole of the rotor. To stop or limit phasing, the locking pin is forced out of the locking pin hole by the locking pin spring axially toward locking cover 20. The locking pin engages locking pin channel 52 to non-rotatably connect the rotor with locking cover 20 and the stator (not shown). Rear surface 50 is substantially perpendicular to radially outward facing surface 30 and radially inward facing surface 40. In an example embodiment, rear surface 50 is not perpendicular to radially outward facing surface 30 and/or radially inward facing surface 40.
Front surface 60 is a radial surface comprising pool 70, a plurality of oil holes 62, a plurality of cover bolts holes 64, and a plurality of counter-bores 66. Front surface 60 is substantially perpendicular to radially outward facing surface 30 and radially inward facing surface 40. In an example embodiment, front surface 60 is not perpendicular to radially outward facing surface 30 and/or radially inward facing surface 40.
Pool 70 is a recess formed in the front surface 60 to allow for oil accumulation. Pool 70 comprises bottom surface 72, outer wall 74, and island 76. Bottom surface 72 is generally a radial surface arranged axially between front surface 60 and rear surface 50 (see
Oil holes 62 are through-bores arranged within pool 70 that extend axially from bottom surface 72 to rear surface 50. Oil holes 62 allow oil to pass, or leak, through locking cover 20 between oil reservoir 90 (formed between locking cover 20 and oil reservoir cover 80) and the chambers of variable camshaft phaser 100, during phasing. This leaking of oil in and out of the chambers, known as oil accumulation, improves the adjustment speed of variable camshaft phaser 100 by accelerating the flow of oil into and out of the chambers. In an example embodiment shown in
Cover bolts holes 64 are through-bores arranged around locking cover 20 such that locking cover 20 can be secured to variable camshaft phaser 100. In an example embodiment, bolts 120 secure locking cover 20 and oil reservoir 80 to variable camshaft phaser 100 by extending through the stator and engaging back plate 110 (shown in
It will be appreciated that various aspects of the disclosure above and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.
