Hybrid module cooling flow

A hybrid module housing includes a bulkhead. The bulkhead has a first radial channel for providing a clutch apply pressure, a second radial channel for providing a clutch cooling flow, and a third radial channel for providing a motor cooling flow. In an example embodiment, the third radial channel is arranged to be on a bottom half of the hybrid module housing when the hybrid module housing is installed in a vehicle. In an example embodiment, the first radial channel and the second radial channel are open at a radially outer surface of the bulkhead, and the third radial channel is sealed at the radially outer surface of the bulkhead. In an example embodiment, the third radial channel includes an axial passage open at a radial wall of the bulkhead.

TECHNICAL FIELD

The present disclosure relates generally to a hybrid module, and more specifically to hybrid module cooling flow.

BACKGROUND

Hybrid modules are known. One example is shown in commonly-assigned U.S. patent application Ser. No. 16/527,329 titled HYBRID MODULE, hereby incorporated by reference as if set forth fully herein.

SUMMARY

Example aspects broadly comprise a hybrid module housing with a bulkhead. The bulkhead has a first radial channel for providing a clutch apply pressure, a second radial channel for providing a clutch cooling flow, and a third radial channel for providing a motor cooling flow. In an example embodiment, the third radial channel is arranged to be on a bottom half of the hybrid module housing when the hybrid module housing is installed in a vehicle. In an example embodiment, the first radial channel and the second radial channel are open at a radially outer surface of the bulkhead, and the third radial channel is sealed at the radially outer surface of the bulkhead. In an example embodiment, the third radial channel includes an axial passage open at a radial wall of the bulkhead.

Other example aspects broadly comprise a hybrid module with the hybrid module housing and a clutch shaft sealed to the bulkhead. In an example embodiment, the hybrid module has a bearing radially supporting the clutch shaft on the hybrid module housing. In an example embodiment, the clutch shaft has a shaft channel in fluid communication with the third radial channel. In some example embodiments, the hybrid module has an outer clutch carrier and a bushing disposed radially between the outer clutch carrier and the clutch shaft. In an example embodiment, the bushing has a flow groove forming a portion of a flow path connecting the second radial channel to the third radial channel. In an example embodiment, the clutch shaft has an inner clutch carrier and a gap between the outer clutch carrier and the inner clutch carrier forms a portion of a flow path connecting the second radial channel to the third radial channel.

Other example aspects broadly comprise a hybrid module with the hybrid module housing and an electric motor rotor. The third radial channel has an axial passage open at a radial wall of the bulkhead and radially proximate the electric motor rotor. In an example embodiment, the electric motor rotor has a radially inwardly extending rim disposed radially outside of the axial passage. In an example embodiment, the hybrid module has an electric motor stator arranged radially outside of the electric motor rotor and fixed to the hybrid module housing.

Other example aspects broadly comprise a cooling circuit for a hybrid module including a first flow path providing a fluid to a clutch pack, and a second flow path providing the fluid from the clutch pack to an electric motor. In an example embodiment, the second flow path has an axial passage radially proximate the electric motor. In an example embodiment, the cooling circuit includes a third flow path fluidically connecting the first flow path and the second flow path and at least partially formed by an outer clutch carrier and an inner clutch carrier. In an example embodiment, the third flow path includes a groove in a bushing. In some example embodiments, the third flow path includes an axial passage formed in a clutch shaft and a radial passage formed in the clutch shaft. In an example embodiment, the radial passage is axially aligned with the second flow path.

DETAILED DESCRIPTION

Embodiments of the present disclosure are described herein. It should be appreciated that like drawing numbers appearing in different drawing views identify identical, or functionally similar, structural elements. Also, it is to be understood that the disclosed embodiments are merely examples and other embodiments can take various and alternative forms. The figures are not necessarily to scale; some features could be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the embodiments. As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures can be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations.

The terminology used herein is for the purpose of describing particular aspects only, and is not intended to limit the scope of the present disclosure. 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 belongs. Although any methods, devices or materials similar or equivalent to those described herein can be used in the practice or testing of the disclosure, the following example methods, devices, and materials are now described.

The following description is made with reference toFIGS. 1-3.FIG. 1illustrates a cross-sectional view of hybrid module100showing cooling flow path200according to an example embodiment.FIG. 2illustrates a top half cross-sectional view of hybrid module100ofFIG. 1.FIG. 3illustrates a bottom half cross-sectional view of hybrid module100ofFIG. 1.

Hybrid module100includes housing102with bulkhead104. Bulkhead104includes radial channel106for providing a clutch apply pressure, radial channel108(shown in dashed lines) for providing a clutch cooling (and dynamic balancing) flow, and radial channel110for providing a motor cooling flow. Radial channel110is arranged to be on a bottom half of hybrid module housing102when the hybrid module housing is installed in a vehicle (not shown). That is, when installed in a vehicle, housing102is oriented as shown inFIGS. 1-3and channel110is on a bottom half so that a cooling oil entering the channel flows down the channel (as shown inFIG. 3) due to gravity.

As can be seen inFIG. 2, radial channel106and radial channel108are open at radially outer surface112of the bulkhead. In other words, the channels extend through surface112and can be connected to a flow source (not shown) via appropriate hydraulic fittings (not shown), for example. As shown inFIG. 3, radial channel110is sealed by plug114at radially outer surface112. Radial channel110includes axial passage116open at radial wall118of the bulkhead. In other words, plug114prevents oil from leaking out of channel110such that oil will fill the channel until the oil level reaches axial passage116and flow axially as described in more detail below.

Hybrid module100includes clutch shaft120sealed to bulkhead104at seal122and bearing123radially supporting the clutch shaft on hybrid module housing102. Damper124is drivingly engaged with shaft120at spline125. Shaft120includes shaft channel126in fluid communication with radial channel110(as seen inFIG. 1). In the example embodiment shown, shaft channel126includes an axial portion128formed as a bore into the shaft, and radial hole130extending from outer surface132to the bore. Oil from the shaft enters channel110from chamber134formed partially by seal122and bearing123. Chamber134is further sealed by seal136between housing102and shaft120.

Hybrid module100includes outer clutch carrier138and bushing140disposed radially between the outer clutch carrier and the clutch shaft. Bushing140includes flow groove142forming a portion of flow path200connecting the radial channel108to radial channel110(ref.FIG. 1). Clutch shaft120includes inner clutch carrier144and gap146between the outer clutch carrier and the inner clutch carrier forms a portion of flow path200connecting radial channel108to radial channel110.

Outer clutch carrier138is a portion of rotor carrier148supporting clutch plates150. Inner clutch carrier144supports clutch plates152. Pressure introduced through radial channel106applies piston154to clamp clutch plates150and152and frictionally connect the clutch shaft to the rotor carrier for torque transmission between a combustion engine (connected to damper124at bolt156) and rotor carrier148. Fluid introduced through channel108flows through clutch plates150and152, and dynamically balances piston154from rotational pressure effects of the fluid. Fluid flows out through radially inner gap146such that, during rotation of outer clutch carrier138(and piston154sealed to the outer clutch carrier), clutch pack chamber157is filled with fluid, aiding in dynamic balancing of piston154.

Hybrid module100includes housing102and electric motor rotor158. Radial channel110includes axial passage116open at radial wall118of bulkhead104. Passage116is radially proximate electric motor rotor158. Electric motor rotor158includes radially inwardly extending rim160disposed radially outside of the axial passage. Rim160is arranged to limit axial flow of fluid received from axial passage116. In other words, flow from axial passage116may drip onto the rotor and rim160keeps the fluid on the rotor and prevents it from flowing back towards the bulkhead. Rim160radially overlaps passage116such that the fluid from the passage is caught by the rotor. Hybrid module100also includes electric motor stator162arranged radially outside of electric motor rotor158and fixed to hybrid module housing102. Rotation of rotor158flings fluid radially outward via centrifugal dynamics to cool stator162. Rotor158and stator162form electric motor164.

Cooling circuit200includes flow path202providing a fluid to clutch pack166, and flow path204providing the fluid from the clutch pack to electric motor164. Flow path204includes axial passage116radially proximate electric motor164. The fluid provides a dynamic balancing to piston154for the clutch pack. In other words, flow path202provides the fluid to a release side of piston154to balance a dynamic effect from rotating apply-side fluid from channel106. Cooling circuit200includes flow path206fluidically connecting paths202and204, and at least partially formed by outer clutch carrier138and inner clutch carrier144. That is, flow path206includes gap146between the carriers. Flow path206also includes groove142in bushing140. Flow path206also includes axial passage128formed in clutch shaft120and radial passage130formed in clutch shaft120. Radial passage130is axially aligned with flow path204.

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